8960 строки
249 KiB
C
8960 строки
249 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* linux/mm/page_alloc.c
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*
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* Manages the free list, the system allocates free pages here.
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* Note that kmalloc() lives in slab.c
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*
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* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
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* Swap reorganised 29.12.95, Stephen Tweedie
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* Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
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* Reshaped it to be a zoned allocator, Ingo Molnar, Red Hat, 1999
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* Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999
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* Zone balancing, Kanoj Sarcar, SGI, Jan 2000
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* Per cpu hot/cold page lists, bulk allocation, Martin J. Bligh, Sept 2002
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* (lots of bits borrowed from Ingo Molnar & Andrew Morton)
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*/
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#include <linux/stddef.h>
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#include <linux/mm.h>
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#include <linux/highmem.h>
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#include <linux/swap.h>
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#include <linux/interrupt.h>
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#include <linux/pagemap.h>
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#include <linux/jiffies.h>
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#include <linux/memblock.h>
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#include <linux/compiler.h>
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#include <linux/kernel.h>
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#include <linux/kasan.h>
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#include <linux/module.h>
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#include <linux/suspend.h>
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#include <linux/pagevec.h>
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#include <linux/blkdev.h>
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#include <linux/slab.h>
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#include <linux/ratelimit.h>
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#include <linux/oom.h>
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#include <linux/topology.h>
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#include <linux/sysctl.h>
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#include <linux/cpu.h>
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#include <linux/cpuset.h>
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#include <linux/memory_hotplug.h>
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#include <linux/nodemask.h>
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#include <linux/vmalloc.h>
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#include <linux/vmstat.h>
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#include <linux/mempolicy.h>
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#include <linux/memremap.h>
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#include <linux/stop_machine.h>
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#include <linux/random.h>
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#include <linux/sort.h>
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#include <linux/pfn.h>
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#include <linux/backing-dev.h>
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#include <linux/fault-inject.h>
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#include <linux/page-isolation.h>
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#include <linux/debugobjects.h>
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#include <linux/kmemleak.h>
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#include <linux/compaction.h>
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#include <trace/events/kmem.h>
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#include <trace/events/oom.h>
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#include <linux/prefetch.h>
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#include <linux/mm_inline.h>
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#include <linux/mmu_notifier.h>
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#include <linux/migrate.h>
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#include <linux/hugetlb.h>
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#include <linux/sched/rt.h>
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#include <linux/sched/mm.h>
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#include <linux/page_owner.h>
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#include <linux/kthread.h>
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#include <linux/memcontrol.h>
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#include <linux/ftrace.h>
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#include <linux/lockdep.h>
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#include <linux/nmi.h>
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#include <linux/psi.h>
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#include <linux/padata.h>
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#include <linux/khugepaged.h>
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#include <linux/buffer_head.h>
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#include <asm/sections.h>
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#include <asm/tlbflush.h>
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#include <asm/div64.h>
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#include "internal.h"
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#include "shuffle.h"
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#include "page_reporting.h"
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/* Free Page Internal flags: for internal, non-pcp variants of free_pages(). */
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typedef int __bitwise fpi_t;
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/* No special request */
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#define FPI_NONE ((__force fpi_t)0)
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/*
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* Skip free page reporting notification for the (possibly merged) page.
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* This does not hinder free page reporting from grabbing the page,
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* reporting it and marking it "reported" - it only skips notifying
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* the free page reporting infrastructure about a newly freed page. For
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* example, used when temporarily pulling a page from a freelist and
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* putting it back unmodified.
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*/
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#define FPI_SKIP_REPORT_NOTIFY ((__force fpi_t)BIT(0))
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/*
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* Place the (possibly merged) page to the tail of the freelist. Will ignore
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* page shuffling (relevant code - e.g., memory onlining - is expected to
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* shuffle the whole zone).
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*
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* Note: No code should rely on this flag for correctness - it's purely
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* to allow for optimizations when handing back either fresh pages
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* (memory onlining) or untouched pages (page isolation, free page
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* reporting).
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*/
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#define FPI_TO_TAIL ((__force fpi_t)BIT(1))
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/* prevent >1 _updater_ of zone percpu pageset ->high and ->batch fields */
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static DEFINE_MUTEX(pcp_batch_high_lock);
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#define MIN_PERCPU_PAGELIST_FRACTION (8)
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#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
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DEFINE_PER_CPU(int, numa_node);
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EXPORT_PER_CPU_SYMBOL(numa_node);
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#endif
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DEFINE_STATIC_KEY_TRUE(vm_numa_stat_key);
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#ifdef CONFIG_HAVE_MEMORYLESS_NODES
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/*
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* N.B., Do NOT reference the '_numa_mem_' per cpu variable directly.
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* It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined.
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* Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem()
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* defined in <linux/topology.h>.
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*/
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DEFINE_PER_CPU(int, _numa_mem_); /* Kernel "local memory" node */
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EXPORT_PER_CPU_SYMBOL(_numa_mem_);
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#endif
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/* work_structs for global per-cpu drains */
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struct pcpu_drain {
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struct zone *zone;
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struct work_struct work;
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};
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static DEFINE_MUTEX(pcpu_drain_mutex);
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static DEFINE_PER_CPU(struct pcpu_drain, pcpu_drain);
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#ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY
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volatile unsigned long latent_entropy __latent_entropy;
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EXPORT_SYMBOL(latent_entropy);
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#endif
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/*
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* Array of node states.
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*/
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nodemask_t node_states[NR_NODE_STATES] __read_mostly = {
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[N_POSSIBLE] = NODE_MASK_ALL,
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[N_ONLINE] = { { [0] = 1UL } },
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#ifndef CONFIG_NUMA
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[N_NORMAL_MEMORY] = { { [0] = 1UL } },
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#ifdef CONFIG_HIGHMEM
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[N_HIGH_MEMORY] = { { [0] = 1UL } },
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#endif
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[N_MEMORY] = { { [0] = 1UL } },
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[N_CPU] = { { [0] = 1UL } },
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#endif /* NUMA */
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};
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EXPORT_SYMBOL(node_states);
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atomic_long_t _totalram_pages __read_mostly;
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EXPORT_SYMBOL(_totalram_pages);
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unsigned long totalreserve_pages __read_mostly;
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unsigned long totalcma_pages __read_mostly;
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int percpu_pagelist_fraction;
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gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK;
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DEFINE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc);
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EXPORT_SYMBOL(init_on_alloc);
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DEFINE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free);
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EXPORT_SYMBOL(init_on_free);
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static bool _init_on_alloc_enabled_early __read_mostly
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= IS_ENABLED(CONFIG_INIT_ON_ALLOC_DEFAULT_ON);
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static int __init early_init_on_alloc(char *buf)
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{
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return kstrtobool(buf, &_init_on_alloc_enabled_early);
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}
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early_param("init_on_alloc", early_init_on_alloc);
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static bool _init_on_free_enabled_early __read_mostly
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= IS_ENABLED(CONFIG_INIT_ON_FREE_DEFAULT_ON);
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static int __init early_init_on_free(char *buf)
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{
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return kstrtobool(buf, &_init_on_free_enabled_early);
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}
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early_param("init_on_free", early_init_on_free);
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/*
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* A cached value of the page's pageblock's migratetype, used when the page is
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* put on a pcplist. Used to avoid the pageblock migratetype lookup when
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* freeing from pcplists in most cases, at the cost of possibly becoming stale.
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* Also the migratetype set in the page does not necessarily match the pcplist
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* index, e.g. page might have MIGRATE_CMA set but be on a pcplist with any
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* other index - this ensures that it will be put on the correct CMA freelist.
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*/
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static inline int get_pcppage_migratetype(struct page *page)
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{
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return page->index;
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}
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static inline void set_pcppage_migratetype(struct page *page, int migratetype)
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{
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page->index = migratetype;
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}
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#ifdef CONFIG_PM_SLEEP
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/*
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* The following functions are used by the suspend/hibernate code to temporarily
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* change gfp_allowed_mask in order to avoid using I/O during memory allocations
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* while devices are suspended. To avoid races with the suspend/hibernate code,
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* they should always be called with system_transition_mutex held
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* (gfp_allowed_mask also should only be modified with system_transition_mutex
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* held, unless the suspend/hibernate code is guaranteed not to run in parallel
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* with that modification).
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*/
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static gfp_t saved_gfp_mask;
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void pm_restore_gfp_mask(void)
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{
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WARN_ON(!mutex_is_locked(&system_transition_mutex));
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if (saved_gfp_mask) {
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gfp_allowed_mask = saved_gfp_mask;
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saved_gfp_mask = 0;
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}
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}
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void pm_restrict_gfp_mask(void)
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{
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WARN_ON(!mutex_is_locked(&system_transition_mutex));
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WARN_ON(saved_gfp_mask);
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saved_gfp_mask = gfp_allowed_mask;
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gfp_allowed_mask &= ~(__GFP_IO | __GFP_FS);
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}
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bool pm_suspended_storage(void)
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{
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if ((gfp_allowed_mask & (__GFP_IO | __GFP_FS)) == (__GFP_IO | __GFP_FS))
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return false;
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return true;
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}
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#endif /* CONFIG_PM_SLEEP */
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#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
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unsigned int pageblock_order __read_mostly;
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#endif
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static void __free_pages_ok(struct page *page, unsigned int order,
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fpi_t fpi_flags);
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/*
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* results with 256, 32 in the lowmem_reserve sysctl:
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* 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
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* 1G machine -> (16M dma, 784M normal, 224M high)
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* NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
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* HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
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* HIGHMEM allocation will leave (224M+784M)/256 of ram reserved in ZONE_DMA
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*
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* TBD: should special case ZONE_DMA32 machines here - in those we normally
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* don't need any ZONE_NORMAL reservation
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*/
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int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES] = {
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#ifdef CONFIG_ZONE_DMA
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[ZONE_DMA] = 256,
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#endif
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#ifdef CONFIG_ZONE_DMA32
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[ZONE_DMA32] = 256,
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#endif
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[ZONE_NORMAL] = 32,
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#ifdef CONFIG_HIGHMEM
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[ZONE_HIGHMEM] = 0,
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#endif
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[ZONE_MOVABLE] = 0,
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};
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static char * const zone_names[MAX_NR_ZONES] = {
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#ifdef CONFIG_ZONE_DMA
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"DMA",
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#endif
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#ifdef CONFIG_ZONE_DMA32
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"DMA32",
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#endif
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"Normal",
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#ifdef CONFIG_HIGHMEM
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"HighMem",
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#endif
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"Movable",
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#ifdef CONFIG_ZONE_DEVICE
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"Device",
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#endif
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};
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const char * const migratetype_names[MIGRATE_TYPES] = {
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"Unmovable",
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"Movable",
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"Reclaimable",
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"HighAtomic",
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#ifdef CONFIG_CMA
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"CMA",
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#endif
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#ifdef CONFIG_MEMORY_ISOLATION
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"Isolate",
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#endif
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};
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compound_page_dtor * const compound_page_dtors[NR_COMPOUND_DTORS] = {
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[NULL_COMPOUND_DTOR] = NULL,
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[COMPOUND_PAGE_DTOR] = free_compound_page,
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#ifdef CONFIG_HUGETLB_PAGE
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[HUGETLB_PAGE_DTOR] = free_huge_page,
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#endif
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#ifdef CONFIG_TRANSPARENT_HUGEPAGE
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[TRANSHUGE_PAGE_DTOR] = free_transhuge_page,
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#endif
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};
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int min_free_kbytes = 1024;
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int user_min_free_kbytes = -1;
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#ifdef CONFIG_DISCONTIGMEM
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/*
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* DiscontigMem defines memory ranges as separate pg_data_t even if the ranges
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* are not on separate NUMA nodes. Functionally this works but with
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* watermark_boost_factor, it can reclaim prematurely as the ranges can be
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* quite small. By default, do not boost watermarks on discontigmem as in
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* many cases very high-order allocations like THP are likely to be
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* unsupported and the premature reclaim offsets the advantage of long-term
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* fragmentation avoidance.
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*/
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int watermark_boost_factor __read_mostly;
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#else
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int watermark_boost_factor __read_mostly = 15000;
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#endif
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int watermark_scale_factor = 10;
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static unsigned long nr_kernel_pages __initdata;
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static unsigned long nr_all_pages __initdata;
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static unsigned long dma_reserve __initdata;
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static unsigned long arch_zone_lowest_possible_pfn[MAX_NR_ZONES] __initdata;
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static unsigned long arch_zone_highest_possible_pfn[MAX_NR_ZONES] __initdata;
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static unsigned long required_kernelcore __initdata;
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static unsigned long required_kernelcore_percent __initdata;
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static unsigned long required_movablecore __initdata;
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static unsigned long required_movablecore_percent __initdata;
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static unsigned long zone_movable_pfn[MAX_NUMNODES] __initdata;
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static bool mirrored_kernelcore __meminitdata;
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/* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
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int movable_zone;
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EXPORT_SYMBOL(movable_zone);
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#if MAX_NUMNODES > 1
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unsigned int nr_node_ids __read_mostly = MAX_NUMNODES;
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unsigned int nr_online_nodes __read_mostly = 1;
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EXPORT_SYMBOL(nr_node_ids);
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EXPORT_SYMBOL(nr_online_nodes);
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#endif
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int page_group_by_mobility_disabled __read_mostly;
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#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
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/*
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* During boot we initialize deferred pages on-demand, as needed, but once
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* page_alloc_init_late() has finished, the deferred pages are all initialized,
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* and we can permanently disable that path.
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*/
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static DEFINE_STATIC_KEY_TRUE(deferred_pages);
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/*
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* Calling kasan_free_pages() only after deferred memory initialization
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* has completed. Poisoning pages during deferred memory init will greatly
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* lengthen the process and cause problem in large memory systems as the
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* deferred pages initialization is done with interrupt disabled.
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*
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* Assuming that there will be no reference to those newly initialized
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* pages before they are ever allocated, this should have no effect on
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* KASAN memory tracking as the poison will be properly inserted at page
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* allocation time. The only corner case is when pages are allocated by
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* on-demand allocation and then freed again before the deferred pages
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* initialization is done, but this is not likely to happen.
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*/
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static inline void kasan_free_nondeferred_pages(struct page *page, int order)
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{
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if (!static_branch_unlikely(&deferred_pages))
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kasan_free_pages(page, order);
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}
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/* Returns true if the struct page for the pfn is uninitialised */
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static inline bool __meminit early_page_uninitialised(unsigned long pfn)
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{
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int nid = early_pfn_to_nid(pfn);
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if (node_online(nid) && pfn >= NODE_DATA(nid)->first_deferred_pfn)
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return true;
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return false;
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}
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/*
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* Returns true when the remaining initialisation should be deferred until
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* later in the boot cycle when it can be parallelised.
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*/
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static bool __meminit
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defer_init(int nid, unsigned long pfn, unsigned long end_pfn)
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{
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static unsigned long prev_end_pfn, nr_initialised;
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/*
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* prev_end_pfn static that contains the end of previous zone
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* No need to protect because called very early in boot before smp_init.
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*/
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if (prev_end_pfn != end_pfn) {
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prev_end_pfn = end_pfn;
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nr_initialised = 0;
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}
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/* Always populate low zones for address-constrained allocations */
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if (end_pfn < pgdat_end_pfn(NODE_DATA(nid)))
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return false;
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if (NODE_DATA(nid)->first_deferred_pfn != ULONG_MAX)
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return true;
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/*
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* We start only with one section of pages, more pages are added as
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* needed until the rest of deferred pages are initialized.
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*/
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nr_initialised++;
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if ((nr_initialised > PAGES_PER_SECTION) &&
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(pfn & (PAGES_PER_SECTION - 1)) == 0) {
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NODE_DATA(nid)->first_deferred_pfn = pfn;
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return true;
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}
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return false;
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}
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#else
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#define kasan_free_nondeferred_pages(p, o) kasan_free_pages(p, o)
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static inline bool early_page_uninitialised(unsigned long pfn)
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{
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return false;
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}
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static inline bool defer_init(int nid, unsigned long pfn, unsigned long end_pfn)
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{
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return false;
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}
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#endif
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/* Return a pointer to the bitmap storing bits affecting a block of pages */
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static inline unsigned long *get_pageblock_bitmap(struct page *page,
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unsigned long pfn)
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{
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#ifdef CONFIG_SPARSEMEM
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return section_to_usemap(__pfn_to_section(pfn));
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#else
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return page_zone(page)->pageblock_flags;
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#endif /* CONFIG_SPARSEMEM */
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}
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static inline int pfn_to_bitidx(struct page *page, unsigned long pfn)
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{
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#ifdef CONFIG_SPARSEMEM
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pfn &= (PAGES_PER_SECTION-1);
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#else
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pfn = pfn - round_down(page_zone(page)->zone_start_pfn, pageblock_nr_pages);
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#endif /* CONFIG_SPARSEMEM */
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return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
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}
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|
static __always_inline
|
|
unsigned long __get_pfnblock_flags_mask(struct page *page,
|
|
unsigned long pfn,
|
|
unsigned long mask)
|
|
{
|
|
unsigned long *bitmap;
|
|
unsigned long bitidx, word_bitidx;
|
|
unsigned long word;
|
|
|
|
bitmap = get_pageblock_bitmap(page, pfn);
|
|
bitidx = pfn_to_bitidx(page, pfn);
|
|
word_bitidx = bitidx / BITS_PER_LONG;
|
|
bitidx &= (BITS_PER_LONG-1);
|
|
|
|
word = bitmap[word_bitidx];
|
|
return (word >> bitidx) & mask;
|
|
}
|
|
|
|
/**
|
|
* get_pfnblock_flags_mask - Return the requested group of flags for the pageblock_nr_pages block of pages
|
|
* @page: The page within the block of interest
|
|
* @pfn: The target page frame number
|
|
* @mask: mask of bits that the caller is interested in
|
|
*
|
|
* Return: pageblock_bits flags
|
|
*/
|
|
unsigned long get_pfnblock_flags_mask(struct page *page, unsigned long pfn,
|
|
unsigned long mask)
|
|
{
|
|
return __get_pfnblock_flags_mask(page, pfn, mask);
|
|
}
|
|
|
|
static __always_inline int get_pfnblock_migratetype(struct page *page, unsigned long pfn)
|
|
{
|
|
return __get_pfnblock_flags_mask(page, pfn, MIGRATETYPE_MASK);
|
|
}
|
|
|
|
/**
|
|
* set_pfnblock_flags_mask - Set the requested group of flags for a pageblock_nr_pages block of pages
|
|
* @page: The page within the block of interest
|
|
* @flags: The flags to set
|
|
* @pfn: The target page frame number
|
|
* @mask: mask of bits that the caller is interested in
|
|
*/
|
|
void set_pfnblock_flags_mask(struct page *page, unsigned long flags,
|
|
unsigned long pfn,
|
|
unsigned long mask)
|
|
{
|
|
unsigned long *bitmap;
|
|
unsigned long bitidx, word_bitidx;
|
|
unsigned long old_word, word;
|
|
|
|
BUILD_BUG_ON(NR_PAGEBLOCK_BITS != 4);
|
|
BUILD_BUG_ON(MIGRATE_TYPES > (1 << PB_migratetype_bits));
|
|
|
|
bitmap = get_pageblock_bitmap(page, pfn);
|
|
bitidx = pfn_to_bitidx(page, pfn);
|
|
word_bitidx = bitidx / BITS_PER_LONG;
|
|
bitidx &= (BITS_PER_LONG-1);
|
|
|
|
VM_BUG_ON_PAGE(!zone_spans_pfn(page_zone(page), pfn), page);
|
|
|
|
mask <<= bitidx;
|
|
flags <<= bitidx;
|
|
|
|
word = READ_ONCE(bitmap[word_bitidx]);
|
|
for (;;) {
|
|
old_word = cmpxchg(&bitmap[word_bitidx], word, (word & ~mask) | flags);
|
|
if (word == old_word)
|
|
break;
|
|
word = old_word;
|
|
}
|
|
}
|
|
|
|
void set_pageblock_migratetype(struct page *page, int migratetype)
|
|
{
|
|
if (unlikely(page_group_by_mobility_disabled &&
|
|
migratetype < MIGRATE_PCPTYPES))
|
|
migratetype = MIGRATE_UNMOVABLE;
|
|
|
|
set_pfnblock_flags_mask(page, (unsigned long)migratetype,
|
|
page_to_pfn(page), MIGRATETYPE_MASK);
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_VM
|
|
static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
|
|
{
|
|
int ret = 0;
|
|
unsigned seq;
|
|
unsigned long pfn = page_to_pfn(page);
|
|
unsigned long sp, start_pfn;
|
|
|
|
do {
|
|
seq = zone_span_seqbegin(zone);
|
|
start_pfn = zone->zone_start_pfn;
|
|
sp = zone->spanned_pages;
|
|
if (!zone_spans_pfn(zone, pfn))
|
|
ret = 1;
|
|
} while (zone_span_seqretry(zone, seq));
|
|
|
|
if (ret)
|
|
pr_err("page 0x%lx outside node %d zone %s [ 0x%lx - 0x%lx ]\n",
|
|
pfn, zone_to_nid(zone), zone->name,
|
|
start_pfn, start_pfn + sp);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int page_is_consistent(struct zone *zone, struct page *page)
|
|
{
|
|
if (!pfn_valid_within(page_to_pfn(page)))
|
|
return 0;
|
|
if (zone != page_zone(page))
|
|
return 0;
|
|
|
|
return 1;
|
|
}
|
|
/*
|
|
* Temporary debugging check for pages not lying within a given zone.
|
|
*/
|
|
static int __maybe_unused bad_range(struct zone *zone, struct page *page)
|
|
{
|
|
if (page_outside_zone_boundaries(zone, page))
|
|
return 1;
|
|
if (!page_is_consistent(zone, page))
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
#else
|
|
static inline int __maybe_unused bad_range(struct zone *zone, struct page *page)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static void bad_page(struct page *page, const char *reason)
|
|
{
|
|
static unsigned long resume;
|
|
static unsigned long nr_shown;
|
|
static unsigned long nr_unshown;
|
|
|
|
/*
|
|
* Allow a burst of 60 reports, then keep quiet for that minute;
|
|
* or allow a steady drip of one report per second.
|
|
*/
|
|
if (nr_shown == 60) {
|
|
if (time_before(jiffies, resume)) {
|
|
nr_unshown++;
|
|
goto out;
|
|
}
|
|
if (nr_unshown) {
|
|
pr_alert(
|
|
"BUG: Bad page state: %lu messages suppressed\n",
|
|
nr_unshown);
|
|
nr_unshown = 0;
|
|
}
|
|
nr_shown = 0;
|
|
}
|
|
if (nr_shown++ == 0)
|
|
resume = jiffies + 60 * HZ;
|
|
|
|
pr_alert("BUG: Bad page state in process %s pfn:%05lx\n",
|
|
current->comm, page_to_pfn(page));
|
|
__dump_page(page, reason);
|
|
dump_page_owner(page);
|
|
|
|
print_modules();
|
|
dump_stack();
|
|
out:
|
|
/* Leave bad fields for debug, except PageBuddy could make trouble */
|
|
page_mapcount_reset(page); /* remove PageBuddy */
|
|
add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
|
|
}
|
|
|
|
/*
|
|
* Higher-order pages are called "compound pages". They are structured thusly:
|
|
*
|
|
* The first PAGE_SIZE page is called the "head page" and have PG_head set.
|
|
*
|
|
* The remaining PAGE_SIZE pages are called "tail pages". PageTail() is encoded
|
|
* in bit 0 of page->compound_head. The rest of bits is pointer to head page.
|
|
*
|
|
* The first tail page's ->compound_dtor holds the offset in array of compound
|
|
* page destructors. See compound_page_dtors.
|
|
*
|
|
* The first tail page's ->compound_order holds the order of allocation.
|
|
* This usage means that zero-order pages may not be compound.
|
|
*/
|
|
|
|
void free_compound_page(struct page *page)
|
|
{
|
|
mem_cgroup_uncharge(page);
|
|
__free_pages_ok(page, compound_order(page), FPI_NONE);
|
|
}
|
|
|
|
void prep_compound_page(struct page *page, unsigned int order)
|
|
{
|
|
int i;
|
|
int nr_pages = 1 << order;
|
|
|
|
__SetPageHead(page);
|
|
for (i = 1; i < nr_pages; i++) {
|
|
struct page *p = page + i;
|
|
set_page_count(p, 0);
|
|
p->mapping = TAIL_MAPPING;
|
|
set_compound_head(p, page);
|
|
}
|
|
|
|
set_compound_page_dtor(page, COMPOUND_PAGE_DTOR);
|
|
set_compound_order(page, order);
|
|
atomic_set(compound_mapcount_ptr(page), -1);
|
|
if (hpage_pincount_available(page))
|
|
atomic_set(compound_pincount_ptr(page), 0);
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_PAGEALLOC
|
|
unsigned int _debug_guardpage_minorder;
|
|
|
|
bool _debug_pagealloc_enabled_early __read_mostly
|
|
= IS_ENABLED(CONFIG_DEBUG_PAGEALLOC_ENABLE_DEFAULT);
|
|
EXPORT_SYMBOL(_debug_pagealloc_enabled_early);
|
|
DEFINE_STATIC_KEY_FALSE(_debug_pagealloc_enabled);
|
|
EXPORT_SYMBOL(_debug_pagealloc_enabled);
|
|
|
|
DEFINE_STATIC_KEY_FALSE(_debug_guardpage_enabled);
|
|
|
|
static int __init early_debug_pagealloc(char *buf)
|
|
{
|
|
return kstrtobool(buf, &_debug_pagealloc_enabled_early);
|
|
}
|
|
early_param("debug_pagealloc", early_debug_pagealloc);
|
|
|
|
static int __init debug_guardpage_minorder_setup(char *buf)
|
|
{
|
|
unsigned long res;
|
|
|
|
if (kstrtoul(buf, 10, &res) < 0 || res > MAX_ORDER / 2) {
|
|
pr_err("Bad debug_guardpage_minorder value\n");
|
|
return 0;
|
|
}
|
|
_debug_guardpage_minorder = res;
|
|
pr_info("Setting debug_guardpage_minorder to %lu\n", res);
|
|
return 0;
|
|
}
|
|
early_param("debug_guardpage_minorder", debug_guardpage_minorder_setup);
|
|
|
|
static inline bool set_page_guard(struct zone *zone, struct page *page,
|
|
unsigned int order, int migratetype)
|
|
{
|
|
if (!debug_guardpage_enabled())
|
|
return false;
|
|
|
|
if (order >= debug_guardpage_minorder())
|
|
return false;
|
|
|
|
__SetPageGuard(page);
|
|
INIT_LIST_HEAD(&page->lru);
|
|
set_page_private(page, order);
|
|
/* Guard pages are not available for any usage */
|
|
__mod_zone_freepage_state(zone, -(1 << order), migratetype);
|
|
|
|
return true;
|
|
}
|
|
|
|
static inline void clear_page_guard(struct zone *zone, struct page *page,
|
|
unsigned int order, int migratetype)
|
|
{
|
|
if (!debug_guardpage_enabled())
|
|
return;
|
|
|
|
__ClearPageGuard(page);
|
|
|
|
set_page_private(page, 0);
|
|
if (!is_migrate_isolate(migratetype))
|
|
__mod_zone_freepage_state(zone, (1 << order), migratetype);
|
|
}
|
|
#else
|
|
static inline bool set_page_guard(struct zone *zone, struct page *page,
|
|
unsigned int order, int migratetype) { return false; }
|
|
static inline void clear_page_guard(struct zone *zone, struct page *page,
|
|
unsigned int order, int migratetype) {}
|
|
#endif
|
|
|
|
/*
|
|
* Enable static keys related to various memory debugging and hardening options.
|
|
* Some override others, and depend on early params that are evaluated in the
|
|
* order of appearance. So we need to first gather the full picture of what was
|
|
* enabled, and then make decisions.
|
|
*/
|
|
void init_mem_debugging_and_hardening(void)
|
|
{
|
|
if (_init_on_alloc_enabled_early) {
|
|
if (page_poisoning_enabled())
|
|
pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, "
|
|
"will take precedence over init_on_alloc\n");
|
|
else
|
|
static_branch_enable(&init_on_alloc);
|
|
}
|
|
if (_init_on_free_enabled_early) {
|
|
if (page_poisoning_enabled())
|
|
pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, "
|
|
"will take precedence over init_on_free\n");
|
|
else
|
|
static_branch_enable(&init_on_free);
|
|
}
|
|
|
|
#ifdef CONFIG_PAGE_POISONING
|
|
/*
|
|
* Page poisoning is debug page alloc for some arches. If
|
|
* either of those options are enabled, enable poisoning.
|
|
*/
|
|
if (page_poisoning_enabled() ||
|
|
(!IS_ENABLED(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) &&
|
|
debug_pagealloc_enabled()))
|
|
static_branch_enable(&_page_poisoning_enabled);
|
|
#endif
|
|
|
|
#ifdef CONFIG_DEBUG_PAGEALLOC
|
|
if (!debug_pagealloc_enabled())
|
|
return;
|
|
|
|
static_branch_enable(&_debug_pagealloc_enabled);
|
|
|
|
if (!debug_guardpage_minorder())
|
|
return;
|
|
|
|
static_branch_enable(&_debug_guardpage_enabled);
|
|
#endif
|
|
}
|
|
|
|
static inline void set_buddy_order(struct page *page, unsigned int order)
|
|
{
|
|
set_page_private(page, order);
|
|
__SetPageBuddy(page);
|
|
}
|
|
|
|
/*
|
|
* This function checks whether a page is free && is the buddy
|
|
* we can coalesce a page and its buddy if
|
|
* (a) the buddy is not in a hole (check before calling!) &&
|
|
* (b) the buddy is in the buddy system &&
|
|
* (c) a page and its buddy have the same order &&
|
|
* (d) a page and its buddy are in the same zone.
|
|
*
|
|
* For recording whether a page is in the buddy system, we set PageBuddy.
|
|
* Setting, clearing, and testing PageBuddy is serialized by zone->lock.
|
|
*
|
|
* For recording page's order, we use page_private(page).
|
|
*/
|
|
static inline bool page_is_buddy(struct page *page, struct page *buddy,
|
|
unsigned int order)
|
|
{
|
|
if (!page_is_guard(buddy) && !PageBuddy(buddy))
|
|
return false;
|
|
|
|
if (buddy_order(buddy) != order)
|
|
return false;
|
|
|
|
/*
|
|
* zone check is done late to avoid uselessly calculating
|
|
* zone/node ids for pages that could never merge.
|
|
*/
|
|
if (page_zone_id(page) != page_zone_id(buddy))
|
|
return false;
|
|
|
|
VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy);
|
|
|
|
return true;
|
|
}
|
|
|
|
#ifdef CONFIG_COMPACTION
|
|
static inline struct capture_control *task_capc(struct zone *zone)
|
|
{
|
|
struct capture_control *capc = current->capture_control;
|
|
|
|
return unlikely(capc) &&
|
|
!(current->flags & PF_KTHREAD) &&
|
|
!capc->page &&
|
|
capc->cc->zone == zone ? capc : NULL;
|
|
}
|
|
|
|
static inline bool
|
|
compaction_capture(struct capture_control *capc, struct page *page,
|
|
int order, int migratetype)
|
|
{
|
|
if (!capc || order != capc->cc->order)
|
|
return false;
|
|
|
|
/* Do not accidentally pollute CMA or isolated regions*/
|
|
if (is_migrate_cma(migratetype) ||
|
|
is_migrate_isolate(migratetype))
|
|
return false;
|
|
|
|
/*
|
|
* Do not let lower order allocations polluate a movable pageblock.
|
|
* This might let an unmovable request use a reclaimable pageblock
|
|
* and vice-versa but no more than normal fallback logic which can
|
|
* have trouble finding a high-order free page.
|
|
*/
|
|
if (order < pageblock_order && migratetype == MIGRATE_MOVABLE)
|
|
return false;
|
|
|
|
capc->page = page;
|
|
return true;
|
|
}
|
|
|
|
#else
|
|
static inline struct capture_control *task_capc(struct zone *zone)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline bool
|
|
compaction_capture(struct capture_control *capc, struct page *page,
|
|
int order, int migratetype)
|
|
{
|
|
return false;
|
|
}
|
|
#endif /* CONFIG_COMPACTION */
|
|
|
|
/* Used for pages not on another list */
|
|
static inline void add_to_free_list(struct page *page, struct zone *zone,
|
|
unsigned int order, int migratetype)
|
|
{
|
|
struct free_area *area = &zone->free_area[order];
|
|
|
|
list_add(&page->lru, &area->free_list[migratetype]);
|
|
area->nr_free++;
|
|
}
|
|
|
|
/* Used for pages not on another list */
|
|
static inline void add_to_free_list_tail(struct page *page, struct zone *zone,
|
|
unsigned int order, int migratetype)
|
|
{
|
|
struct free_area *area = &zone->free_area[order];
|
|
|
|
list_add_tail(&page->lru, &area->free_list[migratetype]);
|
|
area->nr_free++;
|
|
}
|
|
|
|
/*
|
|
* Used for pages which are on another list. Move the pages to the tail
|
|
* of the list - so the moved pages won't immediately be considered for
|
|
* allocation again (e.g., optimization for memory onlining).
|
|
*/
|
|
static inline void move_to_free_list(struct page *page, struct zone *zone,
|
|
unsigned int order, int migratetype)
|
|
{
|
|
struct free_area *area = &zone->free_area[order];
|
|
|
|
list_move_tail(&page->lru, &area->free_list[migratetype]);
|
|
}
|
|
|
|
static inline void del_page_from_free_list(struct page *page, struct zone *zone,
|
|
unsigned int order)
|
|
{
|
|
/* clear reported state and update reported page count */
|
|
if (page_reported(page))
|
|
__ClearPageReported(page);
|
|
|
|
list_del(&page->lru);
|
|
__ClearPageBuddy(page);
|
|
set_page_private(page, 0);
|
|
zone->free_area[order].nr_free--;
|
|
}
|
|
|
|
/*
|
|
* If this is not the largest possible page, check if the buddy
|
|
* of the next-highest order is free. If it is, it's possible
|
|
* that pages are being freed that will coalesce soon. In case,
|
|
* that is happening, add the free page to the tail of the list
|
|
* so it's less likely to be used soon and more likely to be merged
|
|
* as a higher order page
|
|
*/
|
|
static inline bool
|
|
buddy_merge_likely(unsigned long pfn, unsigned long buddy_pfn,
|
|
struct page *page, unsigned int order)
|
|
{
|
|
struct page *higher_page, *higher_buddy;
|
|
unsigned long combined_pfn;
|
|
|
|
if (order >= MAX_ORDER - 2)
|
|
return false;
|
|
|
|
if (!pfn_valid_within(buddy_pfn))
|
|
return false;
|
|
|
|
combined_pfn = buddy_pfn & pfn;
|
|
higher_page = page + (combined_pfn - pfn);
|
|
buddy_pfn = __find_buddy_pfn(combined_pfn, order + 1);
|
|
higher_buddy = higher_page + (buddy_pfn - combined_pfn);
|
|
|
|
return pfn_valid_within(buddy_pfn) &&
|
|
page_is_buddy(higher_page, higher_buddy, order + 1);
|
|
}
|
|
|
|
/*
|
|
* Freeing function for a buddy system allocator.
|
|
*
|
|
* The concept of a buddy system is to maintain direct-mapped table
|
|
* (containing bit values) for memory blocks of various "orders".
|
|
* The bottom level table contains the map for the smallest allocatable
|
|
* units of memory (here, pages), and each level above it describes
|
|
* pairs of units from the levels below, hence, "buddies".
|
|
* At a high level, all that happens here is marking the table entry
|
|
* at the bottom level available, and propagating the changes upward
|
|
* as necessary, plus some accounting needed to play nicely with other
|
|
* parts of the VM system.
|
|
* At each level, we keep a list of pages, which are heads of continuous
|
|
* free pages of length of (1 << order) and marked with PageBuddy.
|
|
* Page's order is recorded in page_private(page) field.
|
|
* So when we are allocating or freeing one, we can derive the state of the
|
|
* other. That is, if we allocate a small block, and both were
|
|
* free, the remainder of the region must be split into blocks.
|
|
* If a block is freed, and its buddy is also free, then this
|
|
* triggers coalescing into a block of larger size.
|
|
*
|
|
* -- nyc
|
|
*/
|
|
|
|
static inline void __free_one_page(struct page *page,
|
|
unsigned long pfn,
|
|
struct zone *zone, unsigned int order,
|
|
int migratetype, fpi_t fpi_flags)
|
|
{
|
|
struct capture_control *capc = task_capc(zone);
|
|
unsigned long buddy_pfn;
|
|
unsigned long combined_pfn;
|
|
unsigned int max_order;
|
|
struct page *buddy;
|
|
bool to_tail;
|
|
|
|
max_order = min_t(unsigned int, MAX_ORDER - 1, pageblock_order);
|
|
|
|
VM_BUG_ON(!zone_is_initialized(zone));
|
|
VM_BUG_ON_PAGE(page->flags & PAGE_FLAGS_CHECK_AT_PREP, page);
|
|
|
|
VM_BUG_ON(migratetype == -1);
|
|
if (likely(!is_migrate_isolate(migratetype)))
|
|
__mod_zone_freepage_state(zone, 1 << order, migratetype);
|
|
|
|
VM_BUG_ON_PAGE(pfn & ((1 << order) - 1), page);
|
|
VM_BUG_ON_PAGE(bad_range(zone, page), page);
|
|
|
|
continue_merging:
|
|
while (order < max_order) {
|
|
if (compaction_capture(capc, page, order, migratetype)) {
|
|
__mod_zone_freepage_state(zone, -(1 << order),
|
|
migratetype);
|
|
return;
|
|
}
|
|
buddy_pfn = __find_buddy_pfn(pfn, order);
|
|
buddy = page + (buddy_pfn - pfn);
|
|
|
|
if (!pfn_valid_within(buddy_pfn))
|
|
goto done_merging;
|
|
if (!page_is_buddy(page, buddy, order))
|
|
goto done_merging;
|
|
/*
|
|
* Our buddy is free or it is CONFIG_DEBUG_PAGEALLOC guard page,
|
|
* merge with it and move up one order.
|
|
*/
|
|
if (page_is_guard(buddy))
|
|
clear_page_guard(zone, buddy, order, migratetype);
|
|
else
|
|
del_page_from_free_list(buddy, zone, order);
|
|
combined_pfn = buddy_pfn & pfn;
|
|
page = page + (combined_pfn - pfn);
|
|
pfn = combined_pfn;
|
|
order++;
|
|
}
|
|
if (order < MAX_ORDER - 1) {
|
|
/* If we are here, it means order is >= pageblock_order.
|
|
* We want to prevent merge between freepages on isolate
|
|
* pageblock and normal pageblock. Without this, pageblock
|
|
* isolation could cause incorrect freepage or CMA accounting.
|
|
*
|
|
* We don't want to hit this code for the more frequent
|
|
* low-order merging.
|
|
*/
|
|
if (unlikely(has_isolate_pageblock(zone))) {
|
|
int buddy_mt;
|
|
|
|
buddy_pfn = __find_buddy_pfn(pfn, order);
|
|
buddy = page + (buddy_pfn - pfn);
|
|
buddy_mt = get_pageblock_migratetype(buddy);
|
|
|
|
if (migratetype != buddy_mt
|
|
&& (is_migrate_isolate(migratetype) ||
|
|
is_migrate_isolate(buddy_mt)))
|
|
goto done_merging;
|
|
}
|
|
max_order = order + 1;
|
|
goto continue_merging;
|
|
}
|
|
|
|
done_merging:
|
|
set_buddy_order(page, order);
|
|
|
|
if (fpi_flags & FPI_TO_TAIL)
|
|
to_tail = true;
|
|
else if (is_shuffle_order(order))
|
|
to_tail = shuffle_pick_tail();
|
|
else
|
|
to_tail = buddy_merge_likely(pfn, buddy_pfn, page, order);
|
|
|
|
if (to_tail)
|
|
add_to_free_list_tail(page, zone, order, migratetype);
|
|
else
|
|
add_to_free_list(page, zone, order, migratetype);
|
|
|
|
/* Notify page reporting subsystem of freed page */
|
|
if (!(fpi_flags & FPI_SKIP_REPORT_NOTIFY))
|
|
page_reporting_notify_free(order);
|
|
}
|
|
|
|
/*
|
|
* A bad page could be due to a number of fields. Instead of multiple branches,
|
|
* try and check multiple fields with one check. The caller must do a detailed
|
|
* check if necessary.
|
|
*/
|
|
static inline bool page_expected_state(struct page *page,
|
|
unsigned long check_flags)
|
|
{
|
|
if (unlikely(atomic_read(&page->_mapcount) != -1))
|
|
return false;
|
|
|
|
if (unlikely((unsigned long)page->mapping |
|
|
page_ref_count(page) |
|
|
#ifdef CONFIG_MEMCG
|
|
(unsigned long)page_memcg(page) |
|
|
#endif
|
|
(page->flags & check_flags)))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
static const char *page_bad_reason(struct page *page, unsigned long flags)
|
|
{
|
|
const char *bad_reason = NULL;
|
|
|
|
if (unlikely(atomic_read(&page->_mapcount) != -1))
|
|
bad_reason = "nonzero mapcount";
|
|
if (unlikely(page->mapping != NULL))
|
|
bad_reason = "non-NULL mapping";
|
|
if (unlikely(page_ref_count(page) != 0))
|
|
bad_reason = "nonzero _refcount";
|
|
if (unlikely(page->flags & flags)) {
|
|
if (flags == PAGE_FLAGS_CHECK_AT_PREP)
|
|
bad_reason = "PAGE_FLAGS_CHECK_AT_PREP flag(s) set";
|
|
else
|
|
bad_reason = "PAGE_FLAGS_CHECK_AT_FREE flag(s) set";
|
|
}
|
|
#ifdef CONFIG_MEMCG
|
|
if (unlikely(page_memcg(page)))
|
|
bad_reason = "page still charged to cgroup";
|
|
#endif
|
|
return bad_reason;
|
|
}
|
|
|
|
static void check_free_page_bad(struct page *page)
|
|
{
|
|
bad_page(page,
|
|
page_bad_reason(page, PAGE_FLAGS_CHECK_AT_FREE));
|
|
}
|
|
|
|
static inline int check_free_page(struct page *page)
|
|
{
|
|
if (likely(page_expected_state(page, PAGE_FLAGS_CHECK_AT_FREE)))
|
|
return 0;
|
|
|
|
/* Something has gone sideways, find it */
|
|
check_free_page_bad(page);
|
|
return 1;
|
|
}
|
|
|
|
static int free_tail_pages_check(struct page *head_page, struct page *page)
|
|
{
|
|
int ret = 1;
|
|
|
|
/*
|
|
* We rely page->lru.next never has bit 0 set, unless the page
|
|
* is PageTail(). Let's make sure that's true even for poisoned ->lru.
|
|
*/
|
|
BUILD_BUG_ON((unsigned long)LIST_POISON1 & 1);
|
|
|
|
if (!IS_ENABLED(CONFIG_DEBUG_VM)) {
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
switch (page - head_page) {
|
|
case 1:
|
|
/* the first tail page: ->mapping may be compound_mapcount() */
|
|
if (unlikely(compound_mapcount(page))) {
|
|
bad_page(page, "nonzero compound_mapcount");
|
|
goto out;
|
|
}
|
|
break;
|
|
case 2:
|
|
/*
|
|
* the second tail page: ->mapping is
|
|
* deferred_list.next -- ignore value.
|
|
*/
|
|
break;
|
|
default:
|
|
if (page->mapping != TAIL_MAPPING) {
|
|
bad_page(page, "corrupted mapping in tail page");
|
|
goto out;
|
|
}
|
|
break;
|
|
}
|
|
if (unlikely(!PageTail(page))) {
|
|
bad_page(page, "PageTail not set");
|
|
goto out;
|
|
}
|
|
if (unlikely(compound_head(page) != head_page)) {
|
|
bad_page(page, "compound_head not consistent");
|
|
goto out;
|
|
}
|
|
ret = 0;
|
|
out:
|
|
page->mapping = NULL;
|
|
clear_compound_head(page);
|
|
return ret;
|
|
}
|
|
|
|
static void kernel_init_free_pages(struct page *page, int numpages)
|
|
{
|
|
int i;
|
|
|
|
/* s390's use of memset() could override KASAN redzones. */
|
|
kasan_disable_current();
|
|
for (i = 0; i < numpages; i++) {
|
|
u8 tag = page_kasan_tag(page + i);
|
|
page_kasan_tag_reset(page + i);
|
|
clear_highpage(page + i);
|
|
page_kasan_tag_set(page + i, tag);
|
|
}
|
|
kasan_enable_current();
|
|
}
|
|
|
|
static __always_inline bool free_pages_prepare(struct page *page,
|
|
unsigned int order, bool check_free)
|
|
{
|
|
int bad = 0;
|
|
|
|
VM_BUG_ON_PAGE(PageTail(page), page);
|
|
|
|
trace_mm_page_free(page, order);
|
|
|
|
if (unlikely(PageHWPoison(page)) && !order) {
|
|
/*
|
|
* Do not let hwpoison pages hit pcplists/buddy
|
|
* Untie memcg state and reset page's owner
|
|
*/
|
|
if (memcg_kmem_enabled() && PageMemcgKmem(page))
|
|
__memcg_kmem_uncharge_page(page, order);
|
|
reset_page_owner(page, order);
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Check tail pages before head page information is cleared to
|
|
* avoid checking PageCompound for order-0 pages.
|
|
*/
|
|
if (unlikely(order)) {
|
|
bool compound = PageCompound(page);
|
|
int i;
|
|
|
|
VM_BUG_ON_PAGE(compound && compound_order(page) != order, page);
|
|
|
|
if (compound)
|
|
ClearPageDoubleMap(page);
|
|
for (i = 1; i < (1 << order); i++) {
|
|
if (compound)
|
|
bad += free_tail_pages_check(page, page + i);
|
|
if (unlikely(check_free_page(page + i))) {
|
|
bad++;
|
|
continue;
|
|
}
|
|
(page + i)->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
|
|
}
|
|
}
|
|
if (PageMappingFlags(page))
|
|
page->mapping = NULL;
|
|
if (memcg_kmem_enabled() && PageMemcgKmem(page))
|
|
__memcg_kmem_uncharge_page(page, order);
|
|
if (check_free)
|
|
bad += check_free_page(page);
|
|
if (bad)
|
|
return false;
|
|
|
|
page_cpupid_reset_last(page);
|
|
page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
|
|
reset_page_owner(page, order);
|
|
|
|
if (!PageHighMem(page)) {
|
|
debug_check_no_locks_freed(page_address(page),
|
|
PAGE_SIZE << order);
|
|
debug_check_no_obj_freed(page_address(page),
|
|
PAGE_SIZE << order);
|
|
}
|
|
if (want_init_on_free())
|
|
kernel_init_free_pages(page, 1 << order);
|
|
|
|
kernel_poison_pages(page, 1 << order);
|
|
|
|
/*
|
|
* With hardware tag-based KASAN, memory tags must be set before the
|
|
* page becomes unavailable via debug_pagealloc or arch_free_page.
|
|
*/
|
|
kasan_free_nondeferred_pages(page, order);
|
|
|
|
/*
|
|
* arch_free_page() can make the page's contents inaccessible. s390
|
|
* does this. So nothing which can access the page's contents should
|
|
* happen after this.
|
|
*/
|
|
arch_free_page(page, order);
|
|
|
|
debug_pagealloc_unmap_pages(page, 1 << order);
|
|
|
|
return true;
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_VM
|
|
/*
|
|
* With DEBUG_VM enabled, order-0 pages are checked immediately when being freed
|
|
* to pcp lists. With debug_pagealloc also enabled, they are also rechecked when
|
|
* moved from pcp lists to free lists.
|
|
*/
|
|
static bool free_pcp_prepare(struct page *page)
|
|
{
|
|
return free_pages_prepare(page, 0, true);
|
|
}
|
|
|
|
static bool bulkfree_pcp_prepare(struct page *page)
|
|
{
|
|
if (debug_pagealloc_enabled_static())
|
|
return check_free_page(page);
|
|
else
|
|
return false;
|
|
}
|
|
#else
|
|
/*
|
|
* With DEBUG_VM disabled, order-0 pages being freed are checked only when
|
|
* moving from pcp lists to free list in order to reduce overhead. With
|
|
* debug_pagealloc enabled, they are checked also immediately when being freed
|
|
* to the pcp lists.
|
|
*/
|
|
static bool free_pcp_prepare(struct page *page)
|
|
{
|
|
if (debug_pagealloc_enabled_static())
|
|
return free_pages_prepare(page, 0, true);
|
|
else
|
|
return free_pages_prepare(page, 0, false);
|
|
}
|
|
|
|
static bool bulkfree_pcp_prepare(struct page *page)
|
|
{
|
|
return check_free_page(page);
|
|
}
|
|
#endif /* CONFIG_DEBUG_VM */
|
|
|
|
static inline void prefetch_buddy(struct page *page)
|
|
{
|
|
unsigned long pfn = page_to_pfn(page);
|
|
unsigned long buddy_pfn = __find_buddy_pfn(pfn, 0);
|
|
struct page *buddy = page + (buddy_pfn - pfn);
|
|
|
|
prefetch(buddy);
|
|
}
|
|
|
|
/*
|
|
* Frees a number of pages from the PCP lists
|
|
* Assumes all pages on list are in same zone, and of same order.
|
|
* count is the number of pages to free.
|
|
*
|
|
* If the zone was previously in an "all pages pinned" state then look to
|
|
* see if this freeing clears that state.
|
|
*
|
|
* And clear the zone's pages_scanned counter, to hold off the "all pages are
|
|
* pinned" detection logic.
|
|
*/
|
|
static void free_pcppages_bulk(struct zone *zone, int count,
|
|
struct per_cpu_pages *pcp)
|
|
{
|
|
int migratetype = 0;
|
|
int batch_free = 0;
|
|
int prefetch_nr = READ_ONCE(pcp->batch);
|
|
bool isolated_pageblocks;
|
|
struct page *page, *tmp;
|
|
LIST_HEAD(head);
|
|
|
|
/*
|
|
* Ensure proper count is passed which otherwise would stuck in the
|
|
* below while (list_empty(list)) loop.
|
|
*/
|
|
count = min(pcp->count, count);
|
|
while (count) {
|
|
struct list_head *list;
|
|
|
|
/*
|
|
* Remove pages from lists in a round-robin fashion. A
|
|
* batch_free count is maintained that is incremented when an
|
|
* empty list is encountered. This is so more pages are freed
|
|
* off fuller lists instead of spinning excessively around empty
|
|
* lists
|
|
*/
|
|
do {
|
|
batch_free++;
|
|
if (++migratetype == MIGRATE_PCPTYPES)
|
|
migratetype = 0;
|
|
list = &pcp->lists[migratetype];
|
|
} while (list_empty(list));
|
|
|
|
/* This is the only non-empty list. Free them all. */
|
|
if (batch_free == MIGRATE_PCPTYPES)
|
|
batch_free = count;
|
|
|
|
do {
|
|
page = list_last_entry(list, struct page, lru);
|
|
/* must delete to avoid corrupting pcp list */
|
|
list_del(&page->lru);
|
|
pcp->count--;
|
|
|
|
if (bulkfree_pcp_prepare(page))
|
|
continue;
|
|
|
|
list_add_tail(&page->lru, &head);
|
|
|
|
/*
|
|
* We are going to put the page back to the global
|
|
* pool, prefetch its buddy to speed up later access
|
|
* under zone->lock. It is believed the overhead of
|
|
* an additional test and calculating buddy_pfn here
|
|
* can be offset by reduced memory latency later. To
|
|
* avoid excessive prefetching due to large count, only
|
|
* prefetch buddy for the first pcp->batch nr of pages.
|
|
*/
|
|
if (prefetch_nr) {
|
|
prefetch_buddy(page);
|
|
prefetch_nr--;
|
|
}
|
|
} while (--count && --batch_free && !list_empty(list));
|
|
}
|
|
|
|
spin_lock(&zone->lock);
|
|
isolated_pageblocks = has_isolate_pageblock(zone);
|
|
|
|
/*
|
|
* Use safe version since after __free_one_page(),
|
|
* page->lru.next will not point to original list.
|
|
*/
|
|
list_for_each_entry_safe(page, tmp, &head, lru) {
|
|
int mt = get_pcppage_migratetype(page);
|
|
/* MIGRATE_ISOLATE page should not go to pcplists */
|
|
VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
|
|
/* Pageblock could have been isolated meanwhile */
|
|
if (unlikely(isolated_pageblocks))
|
|
mt = get_pageblock_migratetype(page);
|
|
|
|
__free_one_page(page, page_to_pfn(page), zone, 0, mt, FPI_NONE);
|
|
trace_mm_page_pcpu_drain(page, 0, mt);
|
|
}
|
|
spin_unlock(&zone->lock);
|
|
}
|
|
|
|
static void free_one_page(struct zone *zone,
|
|
struct page *page, unsigned long pfn,
|
|
unsigned int order,
|
|
int migratetype, fpi_t fpi_flags)
|
|
{
|
|
spin_lock(&zone->lock);
|
|
if (unlikely(has_isolate_pageblock(zone) ||
|
|
is_migrate_isolate(migratetype))) {
|
|
migratetype = get_pfnblock_migratetype(page, pfn);
|
|
}
|
|
__free_one_page(page, pfn, zone, order, migratetype, fpi_flags);
|
|
spin_unlock(&zone->lock);
|
|
}
|
|
|
|
static void __meminit __init_single_page(struct page *page, unsigned long pfn,
|
|
unsigned long zone, int nid)
|
|
{
|
|
mm_zero_struct_page(page);
|
|
set_page_links(page, zone, nid, pfn);
|
|
init_page_count(page);
|
|
page_mapcount_reset(page);
|
|
page_cpupid_reset_last(page);
|
|
page_kasan_tag_reset(page);
|
|
|
|
INIT_LIST_HEAD(&page->lru);
|
|
#ifdef WANT_PAGE_VIRTUAL
|
|
/* The shift won't overflow because ZONE_NORMAL is below 4G. */
|
|
if (!is_highmem_idx(zone))
|
|
set_page_address(page, __va(pfn << PAGE_SHIFT));
|
|
#endif
|
|
}
|
|
|
|
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
|
|
static void __meminit init_reserved_page(unsigned long pfn)
|
|
{
|
|
pg_data_t *pgdat;
|
|
int nid, zid;
|
|
|
|
if (!early_page_uninitialised(pfn))
|
|
return;
|
|
|
|
nid = early_pfn_to_nid(pfn);
|
|
pgdat = NODE_DATA(nid);
|
|
|
|
for (zid = 0; zid < MAX_NR_ZONES; zid++) {
|
|
struct zone *zone = &pgdat->node_zones[zid];
|
|
|
|
if (pfn >= zone->zone_start_pfn && pfn < zone_end_pfn(zone))
|
|
break;
|
|
}
|
|
__init_single_page(pfn_to_page(pfn), pfn, zid, nid);
|
|
}
|
|
#else
|
|
static inline void init_reserved_page(unsigned long pfn)
|
|
{
|
|
}
|
|
#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
|
|
|
|
/*
|
|
* Initialised pages do not have PageReserved set. This function is
|
|
* called for each range allocated by the bootmem allocator and
|
|
* marks the pages PageReserved. The remaining valid pages are later
|
|
* sent to the buddy page allocator.
|
|
*/
|
|
void __meminit reserve_bootmem_region(phys_addr_t start, phys_addr_t end)
|
|
{
|
|
unsigned long start_pfn = PFN_DOWN(start);
|
|
unsigned long end_pfn = PFN_UP(end);
|
|
|
|
for (; start_pfn < end_pfn; start_pfn++) {
|
|
if (pfn_valid(start_pfn)) {
|
|
struct page *page = pfn_to_page(start_pfn);
|
|
|
|
init_reserved_page(start_pfn);
|
|
|
|
/* Avoid false-positive PageTail() */
|
|
INIT_LIST_HEAD(&page->lru);
|
|
|
|
/*
|
|
* no need for atomic set_bit because the struct
|
|
* page is not visible yet so nobody should
|
|
* access it yet.
|
|
*/
|
|
__SetPageReserved(page);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void __free_pages_ok(struct page *page, unsigned int order,
|
|
fpi_t fpi_flags)
|
|
{
|
|
unsigned long flags;
|
|
int migratetype;
|
|
unsigned long pfn = page_to_pfn(page);
|
|
|
|
if (!free_pages_prepare(page, order, true))
|
|
return;
|
|
|
|
migratetype = get_pfnblock_migratetype(page, pfn);
|
|
local_irq_save(flags);
|
|
__count_vm_events(PGFREE, 1 << order);
|
|
free_one_page(page_zone(page), page, pfn, order, migratetype,
|
|
fpi_flags);
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
void __free_pages_core(struct page *page, unsigned int order)
|
|
{
|
|
unsigned int nr_pages = 1 << order;
|
|
struct page *p = page;
|
|
unsigned int loop;
|
|
|
|
/*
|
|
* When initializing the memmap, __init_single_page() sets the refcount
|
|
* of all pages to 1 ("allocated"/"not free"). We have to set the
|
|
* refcount of all involved pages to 0.
|
|
*/
|
|
prefetchw(p);
|
|
for (loop = 0; loop < (nr_pages - 1); loop++, p++) {
|
|
prefetchw(p + 1);
|
|
__ClearPageReserved(p);
|
|
set_page_count(p, 0);
|
|
}
|
|
__ClearPageReserved(p);
|
|
set_page_count(p, 0);
|
|
|
|
atomic_long_add(nr_pages, &page_zone(page)->managed_pages);
|
|
|
|
/*
|
|
* Bypass PCP and place fresh pages right to the tail, primarily
|
|
* relevant for memory onlining.
|
|
*/
|
|
__free_pages_ok(page, order, FPI_TO_TAIL);
|
|
}
|
|
|
|
#ifdef CONFIG_NEED_MULTIPLE_NODES
|
|
|
|
/*
|
|
* During memory init memblocks map pfns to nids. The search is expensive and
|
|
* this caches recent lookups. The implementation of __early_pfn_to_nid
|
|
* treats start/end as pfns.
|
|
*/
|
|
struct mminit_pfnnid_cache {
|
|
unsigned long last_start;
|
|
unsigned long last_end;
|
|
int last_nid;
|
|
};
|
|
|
|
static struct mminit_pfnnid_cache early_pfnnid_cache __meminitdata;
|
|
|
|
/*
|
|
* Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
|
|
*/
|
|
static int __meminit __early_pfn_to_nid(unsigned long pfn,
|
|
struct mminit_pfnnid_cache *state)
|
|
{
|
|
unsigned long start_pfn, end_pfn;
|
|
int nid;
|
|
|
|
if (state->last_start <= pfn && pfn < state->last_end)
|
|
return state->last_nid;
|
|
|
|
nid = memblock_search_pfn_nid(pfn, &start_pfn, &end_pfn);
|
|
if (nid != NUMA_NO_NODE) {
|
|
state->last_start = start_pfn;
|
|
state->last_end = end_pfn;
|
|
state->last_nid = nid;
|
|
}
|
|
|
|
return nid;
|
|
}
|
|
|
|
int __meminit early_pfn_to_nid(unsigned long pfn)
|
|
{
|
|
static DEFINE_SPINLOCK(early_pfn_lock);
|
|
int nid;
|
|
|
|
spin_lock(&early_pfn_lock);
|
|
nid = __early_pfn_to_nid(pfn, &early_pfnnid_cache);
|
|
if (nid < 0)
|
|
nid = first_online_node;
|
|
spin_unlock(&early_pfn_lock);
|
|
|
|
return nid;
|
|
}
|
|
#endif /* CONFIG_NEED_MULTIPLE_NODES */
|
|
|
|
void __init memblock_free_pages(struct page *page, unsigned long pfn,
|
|
unsigned int order)
|
|
{
|
|
if (early_page_uninitialised(pfn))
|
|
return;
|
|
__free_pages_core(page, order);
|
|
}
|
|
|
|
/*
|
|
* Check that the whole (or subset of) a pageblock given by the interval of
|
|
* [start_pfn, end_pfn) is valid and within the same zone, before scanning it
|
|
* with the migration of free compaction scanner. The scanners then need to
|
|
* use only pfn_valid_within() check for arches that allow holes within
|
|
* pageblocks.
|
|
*
|
|
* Return struct page pointer of start_pfn, or NULL if checks were not passed.
|
|
*
|
|
* It's possible on some configurations to have a setup like node0 node1 node0
|
|
* i.e. it's possible that all pages within a zones range of pages do not
|
|
* belong to a single zone. We assume that a border between node0 and node1
|
|
* can occur within a single pageblock, but not a node0 node1 node0
|
|
* interleaving within a single pageblock. It is therefore sufficient to check
|
|
* the first and last page of a pageblock and avoid checking each individual
|
|
* page in a pageblock.
|
|
*/
|
|
struct page *__pageblock_pfn_to_page(unsigned long start_pfn,
|
|
unsigned long end_pfn, struct zone *zone)
|
|
{
|
|
struct page *start_page;
|
|
struct page *end_page;
|
|
|
|
/* end_pfn is one past the range we are checking */
|
|
end_pfn--;
|
|
|
|
if (!pfn_valid(start_pfn) || !pfn_valid(end_pfn))
|
|
return NULL;
|
|
|
|
start_page = pfn_to_online_page(start_pfn);
|
|
if (!start_page)
|
|
return NULL;
|
|
|
|
if (page_zone(start_page) != zone)
|
|
return NULL;
|
|
|
|
end_page = pfn_to_page(end_pfn);
|
|
|
|
/* This gives a shorter code than deriving page_zone(end_page) */
|
|
if (page_zone_id(start_page) != page_zone_id(end_page))
|
|
return NULL;
|
|
|
|
return start_page;
|
|
}
|
|
|
|
void set_zone_contiguous(struct zone *zone)
|
|
{
|
|
unsigned long block_start_pfn = zone->zone_start_pfn;
|
|
unsigned long block_end_pfn;
|
|
|
|
block_end_pfn = ALIGN(block_start_pfn + 1, pageblock_nr_pages);
|
|
for (; block_start_pfn < zone_end_pfn(zone);
|
|
block_start_pfn = block_end_pfn,
|
|
block_end_pfn += pageblock_nr_pages) {
|
|
|
|
block_end_pfn = min(block_end_pfn, zone_end_pfn(zone));
|
|
|
|
if (!__pageblock_pfn_to_page(block_start_pfn,
|
|
block_end_pfn, zone))
|
|
return;
|
|
cond_resched();
|
|
}
|
|
|
|
/* We confirm that there is no hole */
|
|
zone->contiguous = true;
|
|
}
|
|
|
|
void clear_zone_contiguous(struct zone *zone)
|
|
{
|
|
zone->contiguous = false;
|
|
}
|
|
|
|
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
|
|
static void __init deferred_free_range(unsigned long pfn,
|
|
unsigned long nr_pages)
|
|
{
|
|
struct page *page;
|
|
unsigned long i;
|
|
|
|
if (!nr_pages)
|
|
return;
|
|
|
|
page = pfn_to_page(pfn);
|
|
|
|
/* Free a large naturally-aligned chunk if possible */
|
|
if (nr_pages == pageblock_nr_pages &&
|
|
(pfn & (pageblock_nr_pages - 1)) == 0) {
|
|
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
|
|
__free_pages_core(page, pageblock_order);
|
|
return;
|
|
}
|
|
|
|
for (i = 0; i < nr_pages; i++, page++, pfn++) {
|
|
if ((pfn & (pageblock_nr_pages - 1)) == 0)
|
|
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
|
|
__free_pages_core(page, 0);
|
|
}
|
|
}
|
|
|
|
/* Completion tracking for deferred_init_memmap() threads */
|
|
static atomic_t pgdat_init_n_undone __initdata;
|
|
static __initdata DECLARE_COMPLETION(pgdat_init_all_done_comp);
|
|
|
|
static inline void __init pgdat_init_report_one_done(void)
|
|
{
|
|
if (atomic_dec_and_test(&pgdat_init_n_undone))
|
|
complete(&pgdat_init_all_done_comp);
|
|
}
|
|
|
|
/*
|
|
* Returns true if page needs to be initialized or freed to buddy allocator.
|
|
*
|
|
* First we check if pfn is valid on architectures where it is possible to have
|
|
* holes within pageblock_nr_pages. On systems where it is not possible, this
|
|
* function is optimized out.
|
|
*
|
|
* Then, we check if a current large page is valid by only checking the validity
|
|
* of the head pfn.
|
|
*/
|
|
static inline bool __init deferred_pfn_valid(unsigned long pfn)
|
|
{
|
|
if (!pfn_valid_within(pfn))
|
|
return false;
|
|
if (!(pfn & (pageblock_nr_pages - 1)) && !pfn_valid(pfn))
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Free pages to buddy allocator. Try to free aligned pages in
|
|
* pageblock_nr_pages sizes.
|
|
*/
|
|
static void __init deferred_free_pages(unsigned long pfn,
|
|
unsigned long end_pfn)
|
|
{
|
|
unsigned long nr_pgmask = pageblock_nr_pages - 1;
|
|
unsigned long nr_free = 0;
|
|
|
|
for (; pfn < end_pfn; pfn++) {
|
|
if (!deferred_pfn_valid(pfn)) {
|
|
deferred_free_range(pfn - nr_free, nr_free);
|
|
nr_free = 0;
|
|
} else if (!(pfn & nr_pgmask)) {
|
|
deferred_free_range(pfn - nr_free, nr_free);
|
|
nr_free = 1;
|
|
} else {
|
|
nr_free++;
|
|
}
|
|
}
|
|
/* Free the last block of pages to allocator */
|
|
deferred_free_range(pfn - nr_free, nr_free);
|
|
}
|
|
|
|
/*
|
|
* Initialize struct pages. We minimize pfn page lookups and scheduler checks
|
|
* by performing it only once every pageblock_nr_pages.
|
|
* Return number of pages initialized.
|
|
*/
|
|
static unsigned long __init deferred_init_pages(struct zone *zone,
|
|
unsigned long pfn,
|
|
unsigned long end_pfn)
|
|
{
|
|
unsigned long nr_pgmask = pageblock_nr_pages - 1;
|
|
int nid = zone_to_nid(zone);
|
|
unsigned long nr_pages = 0;
|
|
int zid = zone_idx(zone);
|
|
struct page *page = NULL;
|
|
|
|
for (; pfn < end_pfn; pfn++) {
|
|
if (!deferred_pfn_valid(pfn)) {
|
|
page = NULL;
|
|
continue;
|
|
} else if (!page || !(pfn & nr_pgmask)) {
|
|
page = pfn_to_page(pfn);
|
|
} else {
|
|
page++;
|
|
}
|
|
__init_single_page(page, pfn, zid, nid);
|
|
nr_pages++;
|
|
}
|
|
return (nr_pages);
|
|
}
|
|
|
|
/*
|
|
* This function is meant to pre-load the iterator for the zone init.
|
|
* Specifically it walks through the ranges until we are caught up to the
|
|
* first_init_pfn value and exits there. If we never encounter the value we
|
|
* return false indicating there are no valid ranges left.
|
|
*/
|
|
static bool __init
|
|
deferred_init_mem_pfn_range_in_zone(u64 *i, struct zone *zone,
|
|
unsigned long *spfn, unsigned long *epfn,
|
|
unsigned long first_init_pfn)
|
|
{
|
|
u64 j;
|
|
|
|
/*
|
|
* Start out by walking through the ranges in this zone that have
|
|
* already been initialized. We don't need to do anything with them
|
|
* so we just need to flush them out of the system.
|
|
*/
|
|
for_each_free_mem_pfn_range_in_zone(j, zone, spfn, epfn) {
|
|
if (*epfn <= first_init_pfn)
|
|
continue;
|
|
if (*spfn < first_init_pfn)
|
|
*spfn = first_init_pfn;
|
|
*i = j;
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Initialize and free pages. We do it in two loops: first we initialize
|
|
* struct page, then free to buddy allocator, because while we are
|
|
* freeing pages we can access pages that are ahead (computing buddy
|
|
* page in __free_one_page()).
|
|
*
|
|
* In order to try and keep some memory in the cache we have the loop
|
|
* broken along max page order boundaries. This way we will not cause
|
|
* any issues with the buddy page computation.
|
|
*/
|
|
static unsigned long __init
|
|
deferred_init_maxorder(u64 *i, struct zone *zone, unsigned long *start_pfn,
|
|
unsigned long *end_pfn)
|
|
{
|
|
unsigned long mo_pfn = ALIGN(*start_pfn + 1, MAX_ORDER_NR_PAGES);
|
|
unsigned long spfn = *start_pfn, epfn = *end_pfn;
|
|
unsigned long nr_pages = 0;
|
|
u64 j = *i;
|
|
|
|
/* First we loop through and initialize the page values */
|
|
for_each_free_mem_pfn_range_in_zone_from(j, zone, start_pfn, end_pfn) {
|
|
unsigned long t;
|
|
|
|
if (mo_pfn <= *start_pfn)
|
|
break;
|
|
|
|
t = min(mo_pfn, *end_pfn);
|
|
nr_pages += deferred_init_pages(zone, *start_pfn, t);
|
|
|
|
if (mo_pfn < *end_pfn) {
|
|
*start_pfn = mo_pfn;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Reset values and now loop through freeing pages as needed */
|
|
swap(j, *i);
|
|
|
|
for_each_free_mem_pfn_range_in_zone_from(j, zone, &spfn, &epfn) {
|
|
unsigned long t;
|
|
|
|
if (mo_pfn <= spfn)
|
|
break;
|
|
|
|
t = min(mo_pfn, epfn);
|
|
deferred_free_pages(spfn, t);
|
|
|
|
if (mo_pfn <= epfn)
|
|
break;
|
|
}
|
|
|
|
return nr_pages;
|
|
}
|
|
|
|
static void __init
|
|
deferred_init_memmap_chunk(unsigned long start_pfn, unsigned long end_pfn,
|
|
void *arg)
|
|
{
|
|
unsigned long spfn, epfn;
|
|
struct zone *zone = arg;
|
|
u64 i;
|
|
|
|
deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, start_pfn);
|
|
|
|
/*
|
|
* Initialize and free pages in MAX_ORDER sized increments so that we
|
|
* can avoid introducing any issues with the buddy allocator.
|
|
*/
|
|
while (spfn < end_pfn) {
|
|
deferred_init_maxorder(&i, zone, &spfn, &epfn);
|
|
cond_resched();
|
|
}
|
|
}
|
|
|
|
/* An arch may override for more concurrency. */
|
|
__weak int __init
|
|
deferred_page_init_max_threads(const struct cpumask *node_cpumask)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
/* Initialise remaining memory on a node */
|
|
static int __init deferred_init_memmap(void *data)
|
|
{
|
|
pg_data_t *pgdat = data;
|
|
const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id);
|
|
unsigned long spfn = 0, epfn = 0;
|
|
unsigned long first_init_pfn, flags;
|
|
unsigned long start = jiffies;
|
|
struct zone *zone;
|
|
int zid, max_threads;
|
|
u64 i;
|
|
|
|
/* Bind memory initialisation thread to a local node if possible */
|
|
if (!cpumask_empty(cpumask))
|
|
set_cpus_allowed_ptr(current, cpumask);
|
|
|
|
pgdat_resize_lock(pgdat, &flags);
|
|
first_init_pfn = pgdat->first_deferred_pfn;
|
|
if (first_init_pfn == ULONG_MAX) {
|
|
pgdat_resize_unlock(pgdat, &flags);
|
|
pgdat_init_report_one_done();
|
|
return 0;
|
|
}
|
|
|
|
/* Sanity check boundaries */
|
|
BUG_ON(pgdat->first_deferred_pfn < pgdat->node_start_pfn);
|
|
BUG_ON(pgdat->first_deferred_pfn > pgdat_end_pfn(pgdat));
|
|
pgdat->first_deferred_pfn = ULONG_MAX;
|
|
|
|
/*
|
|
* Once we unlock here, the zone cannot be grown anymore, thus if an
|
|
* interrupt thread must allocate this early in boot, zone must be
|
|
* pre-grown prior to start of deferred page initialization.
|
|
*/
|
|
pgdat_resize_unlock(pgdat, &flags);
|
|
|
|
/* Only the highest zone is deferred so find it */
|
|
for (zid = 0; zid < MAX_NR_ZONES; zid++) {
|
|
zone = pgdat->node_zones + zid;
|
|
if (first_init_pfn < zone_end_pfn(zone))
|
|
break;
|
|
}
|
|
|
|
/* If the zone is empty somebody else may have cleared out the zone */
|
|
if (!deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn,
|
|
first_init_pfn))
|
|
goto zone_empty;
|
|
|
|
max_threads = deferred_page_init_max_threads(cpumask);
|
|
|
|
while (spfn < epfn) {
|
|
unsigned long epfn_align = ALIGN(epfn, PAGES_PER_SECTION);
|
|
struct padata_mt_job job = {
|
|
.thread_fn = deferred_init_memmap_chunk,
|
|
.fn_arg = zone,
|
|
.start = spfn,
|
|
.size = epfn_align - spfn,
|
|
.align = PAGES_PER_SECTION,
|
|
.min_chunk = PAGES_PER_SECTION,
|
|
.max_threads = max_threads,
|
|
};
|
|
|
|
padata_do_multithreaded(&job);
|
|
deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn,
|
|
epfn_align);
|
|
}
|
|
zone_empty:
|
|
/* Sanity check that the next zone really is unpopulated */
|
|
WARN_ON(++zid < MAX_NR_ZONES && populated_zone(++zone));
|
|
|
|
pr_info("node %d deferred pages initialised in %ums\n",
|
|
pgdat->node_id, jiffies_to_msecs(jiffies - start));
|
|
|
|
pgdat_init_report_one_done();
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* If this zone has deferred pages, try to grow it by initializing enough
|
|
* deferred pages to satisfy the allocation specified by order, rounded up to
|
|
* the nearest PAGES_PER_SECTION boundary. So we're adding memory in increments
|
|
* of SECTION_SIZE bytes by initializing struct pages in increments of
|
|
* PAGES_PER_SECTION * sizeof(struct page) bytes.
|
|
*
|
|
* Return true when zone was grown, otherwise return false. We return true even
|
|
* when we grow less than requested, to let the caller decide if there are
|
|
* enough pages to satisfy the allocation.
|
|
*
|
|
* Note: We use noinline because this function is needed only during boot, and
|
|
* it is called from a __ref function _deferred_grow_zone. This way we are
|
|
* making sure that it is not inlined into permanent text section.
|
|
*/
|
|
static noinline bool __init
|
|
deferred_grow_zone(struct zone *zone, unsigned int order)
|
|
{
|
|
unsigned long nr_pages_needed = ALIGN(1 << order, PAGES_PER_SECTION);
|
|
pg_data_t *pgdat = zone->zone_pgdat;
|
|
unsigned long first_deferred_pfn = pgdat->first_deferred_pfn;
|
|
unsigned long spfn, epfn, flags;
|
|
unsigned long nr_pages = 0;
|
|
u64 i;
|
|
|
|
/* Only the last zone may have deferred pages */
|
|
if (zone_end_pfn(zone) != pgdat_end_pfn(pgdat))
|
|
return false;
|
|
|
|
pgdat_resize_lock(pgdat, &flags);
|
|
|
|
/*
|
|
* If someone grew this zone while we were waiting for spinlock, return
|
|
* true, as there might be enough pages already.
|
|
*/
|
|
if (first_deferred_pfn != pgdat->first_deferred_pfn) {
|
|
pgdat_resize_unlock(pgdat, &flags);
|
|
return true;
|
|
}
|
|
|
|
/* If the zone is empty somebody else may have cleared out the zone */
|
|
if (!deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn,
|
|
first_deferred_pfn)) {
|
|
pgdat->first_deferred_pfn = ULONG_MAX;
|
|
pgdat_resize_unlock(pgdat, &flags);
|
|
/* Retry only once. */
|
|
return first_deferred_pfn != ULONG_MAX;
|
|
}
|
|
|
|
/*
|
|
* Initialize and free pages in MAX_ORDER sized increments so
|
|
* that we can avoid introducing any issues with the buddy
|
|
* allocator.
|
|
*/
|
|
while (spfn < epfn) {
|
|
/* update our first deferred PFN for this section */
|
|
first_deferred_pfn = spfn;
|
|
|
|
nr_pages += deferred_init_maxorder(&i, zone, &spfn, &epfn);
|
|
touch_nmi_watchdog();
|
|
|
|
/* We should only stop along section boundaries */
|
|
if ((first_deferred_pfn ^ spfn) < PAGES_PER_SECTION)
|
|
continue;
|
|
|
|
/* If our quota has been met we can stop here */
|
|
if (nr_pages >= nr_pages_needed)
|
|
break;
|
|
}
|
|
|
|
pgdat->first_deferred_pfn = spfn;
|
|
pgdat_resize_unlock(pgdat, &flags);
|
|
|
|
return nr_pages > 0;
|
|
}
|
|
|
|
/*
|
|
* deferred_grow_zone() is __init, but it is called from
|
|
* get_page_from_freelist() during early boot until deferred_pages permanently
|
|
* disables this call. This is why we have refdata wrapper to avoid warning,
|
|
* and to ensure that the function body gets unloaded.
|
|
*/
|
|
static bool __ref
|
|
_deferred_grow_zone(struct zone *zone, unsigned int order)
|
|
{
|
|
return deferred_grow_zone(zone, order);
|
|
}
|
|
|
|
#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
|
|
|
|
void __init page_alloc_init_late(void)
|
|
{
|
|
struct zone *zone;
|
|
int nid;
|
|
|
|
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
|
|
|
|
/* There will be num_node_state(N_MEMORY) threads */
|
|
atomic_set(&pgdat_init_n_undone, num_node_state(N_MEMORY));
|
|
for_each_node_state(nid, N_MEMORY) {
|
|
kthread_run(deferred_init_memmap, NODE_DATA(nid), "pgdatinit%d", nid);
|
|
}
|
|
|
|
/* Block until all are initialised */
|
|
wait_for_completion(&pgdat_init_all_done_comp);
|
|
|
|
/*
|
|
* The number of managed pages has changed due to the initialisation
|
|
* so the pcpu batch and high limits needs to be updated or the limits
|
|
* will be artificially small.
|
|
*/
|
|
for_each_populated_zone(zone)
|
|
zone_pcp_update(zone);
|
|
|
|
/*
|
|
* We initialized the rest of the deferred pages. Permanently disable
|
|
* on-demand struct page initialization.
|
|
*/
|
|
static_branch_disable(&deferred_pages);
|
|
|
|
/* Reinit limits that are based on free pages after the kernel is up */
|
|
files_maxfiles_init();
|
|
#endif
|
|
|
|
buffer_init();
|
|
|
|
/* Discard memblock private memory */
|
|
memblock_discard();
|
|
|
|
for_each_node_state(nid, N_MEMORY)
|
|
shuffle_free_memory(NODE_DATA(nid));
|
|
|
|
for_each_populated_zone(zone)
|
|
set_zone_contiguous(zone);
|
|
}
|
|
|
|
#ifdef CONFIG_CMA
|
|
/* Free whole pageblock and set its migration type to MIGRATE_CMA. */
|
|
void __init init_cma_reserved_pageblock(struct page *page)
|
|
{
|
|
unsigned i = pageblock_nr_pages;
|
|
struct page *p = page;
|
|
|
|
do {
|
|
__ClearPageReserved(p);
|
|
set_page_count(p, 0);
|
|
} while (++p, --i);
|
|
|
|
set_pageblock_migratetype(page, MIGRATE_CMA);
|
|
|
|
if (pageblock_order >= MAX_ORDER) {
|
|
i = pageblock_nr_pages;
|
|
p = page;
|
|
do {
|
|
set_page_refcounted(p);
|
|
__free_pages(p, MAX_ORDER - 1);
|
|
p += MAX_ORDER_NR_PAGES;
|
|
} while (i -= MAX_ORDER_NR_PAGES);
|
|
} else {
|
|
set_page_refcounted(page);
|
|
__free_pages(page, pageblock_order);
|
|
}
|
|
|
|
adjust_managed_page_count(page, pageblock_nr_pages);
|
|
page_zone(page)->cma_pages += pageblock_nr_pages;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* The order of subdivision here is critical for the IO subsystem.
|
|
* Please do not alter this order without good reasons and regression
|
|
* testing. Specifically, as large blocks of memory are subdivided,
|
|
* the order in which smaller blocks are delivered depends on the order
|
|
* they're subdivided in this function. This is the primary factor
|
|
* influencing the order in which pages are delivered to the IO
|
|
* subsystem according to empirical testing, and this is also justified
|
|
* by considering the behavior of a buddy system containing a single
|
|
* large block of memory acted on by a series of small allocations.
|
|
* This behavior is a critical factor in sglist merging's success.
|
|
*
|
|
* -- nyc
|
|
*/
|
|
static inline void expand(struct zone *zone, struct page *page,
|
|
int low, int high, int migratetype)
|
|
{
|
|
unsigned long size = 1 << high;
|
|
|
|
while (high > low) {
|
|
high--;
|
|
size >>= 1;
|
|
VM_BUG_ON_PAGE(bad_range(zone, &page[size]), &page[size]);
|
|
|
|
/*
|
|
* Mark as guard pages (or page), that will allow to
|
|
* merge back to allocator when buddy will be freed.
|
|
* Corresponding page table entries will not be touched,
|
|
* pages will stay not present in virtual address space
|
|
*/
|
|
if (set_page_guard(zone, &page[size], high, migratetype))
|
|
continue;
|
|
|
|
add_to_free_list(&page[size], zone, high, migratetype);
|
|
set_buddy_order(&page[size], high);
|
|
}
|
|
}
|
|
|
|
static void check_new_page_bad(struct page *page)
|
|
{
|
|
if (unlikely(page->flags & __PG_HWPOISON)) {
|
|
/* Don't complain about hwpoisoned pages */
|
|
page_mapcount_reset(page); /* remove PageBuddy */
|
|
return;
|
|
}
|
|
|
|
bad_page(page,
|
|
page_bad_reason(page, PAGE_FLAGS_CHECK_AT_PREP));
|
|
}
|
|
|
|
/*
|
|
* This page is about to be returned from the page allocator
|
|
*/
|
|
static inline int check_new_page(struct page *page)
|
|
{
|
|
if (likely(page_expected_state(page,
|
|
PAGE_FLAGS_CHECK_AT_PREP|__PG_HWPOISON)))
|
|
return 0;
|
|
|
|
check_new_page_bad(page);
|
|
return 1;
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_VM
|
|
/*
|
|
* With DEBUG_VM enabled, order-0 pages are checked for expected state when
|
|
* being allocated from pcp lists. With debug_pagealloc also enabled, they are
|
|
* also checked when pcp lists are refilled from the free lists.
|
|
*/
|
|
static inline bool check_pcp_refill(struct page *page)
|
|
{
|
|
if (debug_pagealloc_enabled_static())
|
|
return check_new_page(page);
|
|
else
|
|
return false;
|
|
}
|
|
|
|
static inline bool check_new_pcp(struct page *page)
|
|
{
|
|
return check_new_page(page);
|
|
}
|
|
#else
|
|
/*
|
|
* With DEBUG_VM disabled, free order-0 pages are checked for expected state
|
|
* when pcp lists are being refilled from the free lists. With debug_pagealloc
|
|
* enabled, they are also checked when being allocated from the pcp lists.
|
|
*/
|
|
static inline bool check_pcp_refill(struct page *page)
|
|
{
|
|
return check_new_page(page);
|
|
}
|
|
static inline bool check_new_pcp(struct page *page)
|
|
{
|
|
if (debug_pagealloc_enabled_static())
|
|
return check_new_page(page);
|
|
else
|
|
return false;
|
|
}
|
|
#endif /* CONFIG_DEBUG_VM */
|
|
|
|
static bool check_new_pages(struct page *page, unsigned int order)
|
|
{
|
|
int i;
|
|
for (i = 0; i < (1 << order); i++) {
|
|
struct page *p = page + i;
|
|
|
|
if (unlikely(check_new_page(p)))
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
inline void post_alloc_hook(struct page *page, unsigned int order,
|
|
gfp_t gfp_flags)
|
|
{
|
|
set_page_private(page, 0);
|
|
set_page_refcounted(page);
|
|
|
|
arch_alloc_page(page, order);
|
|
debug_pagealloc_map_pages(page, 1 << order);
|
|
kasan_alloc_pages(page, order);
|
|
kernel_unpoison_pages(page, 1 << order);
|
|
set_page_owner(page, order, gfp_flags);
|
|
|
|
if (!want_init_on_free() && want_init_on_alloc(gfp_flags))
|
|
kernel_init_free_pages(page, 1 << order);
|
|
}
|
|
|
|
static void prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags,
|
|
unsigned int alloc_flags)
|
|
{
|
|
post_alloc_hook(page, order, gfp_flags);
|
|
|
|
if (order && (gfp_flags & __GFP_COMP))
|
|
prep_compound_page(page, order);
|
|
|
|
/*
|
|
* page is set pfmemalloc when ALLOC_NO_WATERMARKS was necessary to
|
|
* allocate the page. The expectation is that the caller is taking
|
|
* steps that will free more memory. The caller should avoid the page
|
|
* being used for !PFMEMALLOC purposes.
|
|
*/
|
|
if (alloc_flags & ALLOC_NO_WATERMARKS)
|
|
set_page_pfmemalloc(page);
|
|
else
|
|
clear_page_pfmemalloc(page);
|
|
}
|
|
|
|
/*
|
|
* Go through the free lists for the given migratetype and remove
|
|
* the smallest available page from the freelists
|
|
*/
|
|
static __always_inline
|
|
struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
|
|
int migratetype)
|
|
{
|
|
unsigned int current_order;
|
|
struct free_area *area;
|
|
struct page *page;
|
|
|
|
/* Find a page of the appropriate size in the preferred list */
|
|
for (current_order = order; current_order < MAX_ORDER; ++current_order) {
|
|
area = &(zone->free_area[current_order]);
|
|
page = get_page_from_free_area(area, migratetype);
|
|
if (!page)
|
|
continue;
|
|
del_page_from_free_list(page, zone, current_order);
|
|
expand(zone, page, order, current_order, migratetype);
|
|
set_pcppage_migratetype(page, migratetype);
|
|
return page;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
|
|
/*
|
|
* This array describes the order lists are fallen back to when
|
|
* the free lists for the desirable migrate type are depleted
|
|
*/
|
|
static int fallbacks[MIGRATE_TYPES][3] = {
|
|
[MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_TYPES },
|
|
[MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_TYPES },
|
|
[MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_TYPES },
|
|
#ifdef CONFIG_CMA
|
|
[MIGRATE_CMA] = { MIGRATE_TYPES }, /* Never used */
|
|
#endif
|
|
#ifdef CONFIG_MEMORY_ISOLATION
|
|
[MIGRATE_ISOLATE] = { MIGRATE_TYPES }, /* Never used */
|
|
#endif
|
|
};
|
|
|
|
#ifdef CONFIG_CMA
|
|
static __always_inline struct page *__rmqueue_cma_fallback(struct zone *zone,
|
|
unsigned int order)
|
|
{
|
|
return __rmqueue_smallest(zone, order, MIGRATE_CMA);
|
|
}
|
|
#else
|
|
static inline struct page *__rmqueue_cma_fallback(struct zone *zone,
|
|
unsigned int order) { return NULL; }
|
|
#endif
|
|
|
|
/*
|
|
* Move the free pages in a range to the freelist tail of the requested type.
|
|
* Note that start_page and end_pages are not aligned on a pageblock
|
|
* boundary. If alignment is required, use move_freepages_block()
|
|
*/
|
|
static int move_freepages(struct zone *zone,
|
|
struct page *start_page, struct page *end_page,
|
|
int migratetype, int *num_movable)
|
|
{
|
|
struct page *page;
|
|
unsigned int order;
|
|
int pages_moved = 0;
|
|
|
|
for (page = start_page; page <= end_page;) {
|
|
if (!pfn_valid_within(page_to_pfn(page))) {
|
|
page++;
|
|
continue;
|
|
}
|
|
|
|
if (!PageBuddy(page)) {
|
|
/*
|
|
* We assume that pages that could be isolated for
|
|
* migration are movable. But we don't actually try
|
|
* isolating, as that would be expensive.
|
|
*/
|
|
if (num_movable &&
|
|
(PageLRU(page) || __PageMovable(page)))
|
|
(*num_movable)++;
|
|
|
|
page++;
|
|
continue;
|
|
}
|
|
|
|
/* Make sure we are not inadvertently changing nodes */
|
|
VM_BUG_ON_PAGE(page_to_nid(page) != zone_to_nid(zone), page);
|
|
VM_BUG_ON_PAGE(page_zone(page) != zone, page);
|
|
|
|
order = buddy_order(page);
|
|
move_to_free_list(page, zone, order, migratetype);
|
|
page += 1 << order;
|
|
pages_moved += 1 << order;
|
|
}
|
|
|
|
return pages_moved;
|
|
}
|
|
|
|
int move_freepages_block(struct zone *zone, struct page *page,
|
|
int migratetype, int *num_movable)
|
|
{
|
|
unsigned long start_pfn, end_pfn;
|
|
struct page *start_page, *end_page;
|
|
|
|
if (num_movable)
|
|
*num_movable = 0;
|
|
|
|
start_pfn = page_to_pfn(page);
|
|
start_pfn = start_pfn & ~(pageblock_nr_pages-1);
|
|
start_page = pfn_to_page(start_pfn);
|
|
end_page = start_page + pageblock_nr_pages - 1;
|
|
end_pfn = start_pfn + pageblock_nr_pages - 1;
|
|
|
|
/* Do not cross zone boundaries */
|
|
if (!zone_spans_pfn(zone, start_pfn))
|
|
start_page = page;
|
|
if (!zone_spans_pfn(zone, end_pfn))
|
|
return 0;
|
|
|
|
return move_freepages(zone, start_page, end_page, migratetype,
|
|
num_movable);
|
|
}
|
|
|
|
static void change_pageblock_range(struct page *pageblock_page,
|
|
int start_order, int migratetype)
|
|
{
|
|
int nr_pageblocks = 1 << (start_order - pageblock_order);
|
|
|
|
while (nr_pageblocks--) {
|
|
set_pageblock_migratetype(pageblock_page, migratetype);
|
|
pageblock_page += pageblock_nr_pages;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* When we are falling back to another migratetype during allocation, try to
|
|
* steal extra free pages from the same pageblocks to satisfy further
|
|
* allocations, instead of polluting multiple pageblocks.
|
|
*
|
|
* If we are stealing a relatively large buddy page, it is likely there will
|
|
* be more free pages in the pageblock, so try to steal them all. For
|
|
* reclaimable and unmovable allocations, we steal regardless of page size,
|
|
* as fragmentation caused by those allocations polluting movable pageblocks
|
|
* is worse than movable allocations stealing from unmovable and reclaimable
|
|
* pageblocks.
|
|
*/
|
|
static bool can_steal_fallback(unsigned int order, int start_mt)
|
|
{
|
|
/*
|
|
* Leaving this order check is intended, although there is
|
|
* relaxed order check in next check. The reason is that
|
|
* we can actually steal whole pageblock if this condition met,
|
|
* but, below check doesn't guarantee it and that is just heuristic
|
|
* so could be changed anytime.
|
|
*/
|
|
if (order >= pageblock_order)
|
|
return true;
|
|
|
|
if (order >= pageblock_order / 2 ||
|
|
start_mt == MIGRATE_RECLAIMABLE ||
|
|
start_mt == MIGRATE_UNMOVABLE ||
|
|
page_group_by_mobility_disabled)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
static inline bool boost_watermark(struct zone *zone)
|
|
{
|
|
unsigned long max_boost;
|
|
|
|
if (!watermark_boost_factor)
|
|
return false;
|
|
/*
|
|
* Don't bother in zones that are unlikely to produce results.
|
|
* On small machines, including kdump capture kernels running
|
|
* in a small area, boosting the watermark can cause an out of
|
|
* memory situation immediately.
|
|
*/
|
|
if ((pageblock_nr_pages * 4) > zone_managed_pages(zone))
|
|
return false;
|
|
|
|
max_boost = mult_frac(zone->_watermark[WMARK_HIGH],
|
|
watermark_boost_factor, 10000);
|
|
|
|
/*
|
|
* high watermark may be uninitialised if fragmentation occurs
|
|
* very early in boot so do not boost. We do not fall
|
|
* through and boost by pageblock_nr_pages as failing
|
|
* allocations that early means that reclaim is not going
|
|
* to help and it may even be impossible to reclaim the
|
|
* boosted watermark resulting in a hang.
|
|
*/
|
|
if (!max_boost)
|
|
return false;
|
|
|
|
max_boost = max(pageblock_nr_pages, max_boost);
|
|
|
|
zone->watermark_boost = min(zone->watermark_boost + pageblock_nr_pages,
|
|
max_boost);
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* This function implements actual steal behaviour. If order is large enough,
|
|
* we can steal whole pageblock. If not, we first move freepages in this
|
|
* pageblock to our migratetype and determine how many already-allocated pages
|
|
* are there in the pageblock with a compatible migratetype. If at least half
|
|
* of pages are free or compatible, we can change migratetype of the pageblock
|
|
* itself, so pages freed in the future will be put on the correct free list.
|
|
*/
|
|
static void steal_suitable_fallback(struct zone *zone, struct page *page,
|
|
unsigned int alloc_flags, int start_type, bool whole_block)
|
|
{
|
|
unsigned int current_order = buddy_order(page);
|
|
int free_pages, movable_pages, alike_pages;
|
|
int old_block_type;
|
|
|
|
old_block_type = get_pageblock_migratetype(page);
|
|
|
|
/*
|
|
* This can happen due to races and we want to prevent broken
|
|
* highatomic accounting.
|
|
*/
|
|
if (is_migrate_highatomic(old_block_type))
|
|
goto single_page;
|
|
|
|
/* Take ownership for orders >= pageblock_order */
|
|
if (current_order >= pageblock_order) {
|
|
change_pageblock_range(page, current_order, start_type);
|
|
goto single_page;
|
|
}
|
|
|
|
/*
|
|
* Boost watermarks to increase reclaim pressure to reduce the
|
|
* likelihood of future fallbacks. Wake kswapd now as the node
|
|
* may be balanced overall and kswapd will not wake naturally.
|
|
*/
|
|
if (boost_watermark(zone) && (alloc_flags & ALLOC_KSWAPD))
|
|
set_bit(ZONE_BOOSTED_WATERMARK, &zone->flags);
|
|
|
|
/* We are not allowed to try stealing from the whole block */
|
|
if (!whole_block)
|
|
goto single_page;
|
|
|
|
free_pages = move_freepages_block(zone, page, start_type,
|
|
&movable_pages);
|
|
/*
|
|
* Determine how many pages are compatible with our allocation.
|
|
* For movable allocation, it's the number of movable pages which
|
|
* we just obtained. For other types it's a bit more tricky.
|
|
*/
|
|
if (start_type == MIGRATE_MOVABLE) {
|
|
alike_pages = movable_pages;
|
|
} else {
|
|
/*
|
|
* If we are falling back a RECLAIMABLE or UNMOVABLE allocation
|
|
* to MOVABLE pageblock, consider all non-movable pages as
|
|
* compatible. If it's UNMOVABLE falling back to RECLAIMABLE or
|
|
* vice versa, be conservative since we can't distinguish the
|
|
* exact migratetype of non-movable pages.
|
|
*/
|
|
if (old_block_type == MIGRATE_MOVABLE)
|
|
alike_pages = pageblock_nr_pages
|
|
- (free_pages + movable_pages);
|
|
else
|
|
alike_pages = 0;
|
|
}
|
|
|
|
/* moving whole block can fail due to zone boundary conditions */
|
|
if (!free_pages)
|
|
goto single_page;
|
|
|
|
/*
|
|
* If a sufficient number of pages in the block are either free or of
|
|
* comparable migratability as our allocation, claim the whole block.
|
|
*/
|
|
if (free_pages + alike_pages >= (1 << (pageblock_order-1)) ||
|
|
page_group_by_mobility_disabled)
|
|
set_pageblock_migratetype(page, start_type);
|
|
|
|
return;
|
|
|
|
single_page:
|
|
move_to_free_list(page, zone, current_order, start_type);
|
|
}
|
|
|
|
/*
|
|
* Check whether there is a suitable fallback freepage with requested order.
|
|
* If only_stealable is true, this function returns fallback_mt only if
|
|
* we can steal other freepages all together. This would help to reduce
|
|
* fragmentation due to mixed migratetype pages in one pageblock.
|
|
*/
|
|
int find_suitable_fallback(struct free_area *area, unsigned int order,
|
|
int migratetype, bool only_stealable, bool *can_steal)
|
|
{
|
|
int i;
|
|
int fallback_mt;
|
|
|
|
if (area->nr_free == 0)
|
|
return -1;
|
|
|
|
*can_steal = false;
|
|
for (i = 0;; i++) {
|
|
fallback_mt = fallbacks[migratetype][i];
|
|
if (fallback_mt == MIGRATE_TYPES)
|
|
break;
|
|
|
|
if (free_area_empty(area, fallback_mt))
|
|
continue;
|
|
|
|
if (can_steal_fallback(order, migratetype))
|
|
*can_steal = true;
|
|
|
|
if (!only_stealable)
|
|
return fallback_mt;
|
|
|
|
if (*can_steal)
|
|
return fallback_mt;
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Reserve a pageblock for exclusive use of high-order atomic allocations if
|
|
* there are no empty page blocks that contain a page with a suitable order
|
|
*/
|
|
static void reserve_highatomic_pageblock(struct page *page, struct zone *zone,
|
|
unsigned int alloc_order)
|
|
{
|
|
int mt;
|
|
unsigned long max_managed, flags;
|
|
|
|
/*
|
|
* Limit the number reserved to 1 pageblock or roughly 1% of a zone.
|
|
* Check is race-prone but harmless.
|
|
*/
|
|
max_managed = (zone_managed_pages(zone) / 100) + pageblock_nr_pages;
|
|
if (zone->nr_reserved_highatomic >= max_managed)
|
|
return;
|
|
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
|
|
/* Recheck the nr_reserved_highatomic limit under the lock */
|
|
if (zone->nr_reserved_highatomic >= max_managed)
|
|
goto out_unlock;
|
|
|
|
/* Yoink! */
|
|
mt = get_pageblock_migratetype(page);
|
|
if (!is_migrate_highatomic(mt) && !is_migrate_isolate(mt)
|
|
&& !is_migrate_cma(mt)) {
|
|
zone->nr_reserved_highatomic += pageblock_nr_pages;
|
|
set_pageblock_migratetype(page, MIGRATE_HIGHATOMIC);
|
|
move_freepages_block(zone, page, MIGRATE_HIGHATOMIC, NULL);
|
|
}
|
|
|
|
out_unlock:
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
}
|
|
|
|
/*
|
|
* Used when an allocation is about to fail under memory pressure. This
|
|
* potentially hurts the reliability of high-order allocations when under
|
|
* intense memory pressure but failed atomic allocations should be easier
|
|
* to recover from than an OOM.
|
|
*
|
|
* If @force is true, try to unreserve a pageblock even though highatomic
|
|
* pageblock is exhausted.
|
|
*/
|
|
static bool unreserve_highatomic_pageblock(const struct alloc_context *ac,
|
|
bool force)
|
|
{
|
|
struct zonelist *zonelist = ac->zonelist;
|
|
unsigned long flags;
|
|
struct zoneref *z;
|
|
struct zone *zone;
|
|
struct page *page;
|
|
int order;
|
|
bool ret;
|
|
|
|
for_each_zone_zonelist_nodemask(zone, z, zonelist, ac->highest_zoneidx,
|
|
ac->nodemask) {
|
|
/*
|
|
* Preserve at least one pageblock unless memory pressure
|
|
* is really high.
|
|
*/
|
|
if (!force && zone->nr_reserved_highatomic <=
|
|
pageblock_nr_pages)
|
|
continue;
|
|
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
for (order = 0; order < MAX_ORDER; order++) {
|
|
struct free_area *area = &(zone->free_area[order]);
|
|
|
|
page = get_page_from_free_area(area, MIGRATE_HIGHATOMIC);
|
|
if (!page)
|
|
continue;
|
|
|
|
/*
|
|
* In page freeing path, migratetype change is racy so
|
|
* we can counter several free pages in a pageblock
|
|
* in this loop althoug we changed the pageblock type
|
|
* from highatomic to ac->migratetype. So we should
|
|
* adjust the count once.
|
|
*/
|
|
if (is_migrate_highatomic_page(page)) {
|
|
/*
|
|
* It should never happen but changes to
|
|
* locking could inadvertently allow a per-cpu
|
|
* drain to add pages to MIGRATE_HIGHATOMIC
|
|
* while unreserving so be safe and watch for
|
|
* underflows.
|
|
*/
|
|
zone->nr_reserved_highatomic -= min(
|
|
pageblock_nr_pages,
|
|
zone->nr_reserved_highatomic);
|
|
}
|
|
|
|
/*
|
|
* Convert to ac->migratetype and avoid the normal
|
|
* pageblock stealing heuristics. Minimally, the caller
|
|
* is doing the work and needs the pages. More
|
|
* importantly, if the block was always converted to
|
|
* MIGRATE_UNMOVABLE or another type then the number
|
|
* of pageblocks that cannot be completely freed
|
|
* may increase.
|
|
*/
|
|
set_pageblock_migratetype(page, ac->migratetype);
|
|
ret = move_freepages_block(zone, page, ac->migratetype,
|
|
NULL);
|
|
if (ret) {
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
return ret;
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Try finding a free buddy page on the fallback list and put it on the free
|
|
* list of requested migratetype, possibly along with other pages from the same
|
|
* block, depending on fragmentation avoidance heuristics. Returns true if
|
|
* fallback was found so that __rmqueue_smallest() can grab it.
|
|
*
|
|
* The use of signed ints for order and current_order is a deliberate
|
|
* deviation from the rest of this file, to make the for loop
|
|
* condition simpler.
|
|
*/
|
|
static __always_inline bool
|
|
__rmqueue_fallback(struct zone *zone, int order, int start_migratetype,
|
|
unsigned int alloc_flags)
|
|
{
|
|
struct free_area *area;
|
|
int current_order;
|
|
int min_order = order;
|
|
struct page *page;
|
|
int fallback_mt;
|
|
bool can_steal;
|
|
|
|
/*
|
|
* Do not steal pages from freelists belonging to other pageblocks
|
|
* i.e. orders < pageblock_order. If there are no local zones free,
|
|
* the zonelists will be reiterated without ALLOC_NOFRAGMENT.
|
|
*/
|
|
if (alloc_flags & ALLOC_NOFRAGMENT)
|
|
min_order = pageblock_order;
|
|
|
|
/*
|
|
* Find the largest available free page in the other list. This roughly
|
|
* approximates finding the pageblock with the most free pages, which
|
|
* would be too costly to do exactly.
|
|
*/
|
|
for (current_order = MAX_ORDER - 1; current_order >= min_order;
|
|
--current_order) {
|
|
area = &(zone->free_area[current_order]);
|
|
fallback_mt = find_suitable_fallback(area, current_order,
|
|
start_migratetype, false, &can_steal);
|
|
if (fallback_mt == -1)
|
|
continue;
|
|
|
|
/*
|
|
* We cannot steal all free pages from the pageblock and the
|
|
* requested migratetype is movable. In that case it's better to
|
|
* steal and split the smallest available page instead of the
|
|
* largest available page, because even if the next movable
|
|
* allocation falls back into a different pageblock than this
|
|
* one, it won't cause permanent fragmentation.
|
|
*/
|
|
if (!can_steal && start_migratetype == MIGRATE_MOVABLE
|
|
&& current_order > order)
|
|
goto find_smallest;
|
|
|
|
goto do_steal;
|
|
}
|
|
|
|
return false;
|
|
|
|
find_smallest:
|
|
for (current_order = order; current_order < MAX_ORDER;
|
|
current_order++) {
|
|
area = &(zone->free_area[current_order]);
|
|
fallback_mt = find_suitable_fallback(area, current_order,
|
|
start_migratetype, false, &can_steal);
|
|
if (fallback_mt != -1)
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* This should not happen - we already found a suitable fallback
|
|
* when looking for the largest page.
|
|
*/
|
|
VM_BUG_ON(current_order == MAX_ORDER);
|
|
|
|
do_steal:
|
|
page = get_page_from_free_area(area, fallback_mt);
|
|
|
|
steal_suitable_fallback(zone, page, alloc_flags, start_migratetype,
|
|
can_steal);
|
|
|
|
trace_mm_page_alloc_extfrag(page, order, current_order,
|
|
start_migratetype, fallback_mt);
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
/*
|
|
* Do the hard work of removing an element from the buddy allocator.
|
|
* Call me with the zone->lock already held.
|
|
*/
|
|
static __always_inline struct page *
|
|
__rmqueue(struct zone *zone, unsigned int order, int migratetype,
|
|
unsigned int alloc_flags)
|
|
{
|
|
struct page *page;
|
|
|
|
if (IS_ENABLED(CONFIG_CMA)) {
|
|
/*
|
|
* Balance movable allocations between regular and CMA areas by
|
|
* allocating from CMA when over half of the zone's free memory
|
|
* is in the CMA area.
|
|
*/
|
|
if (alloc_flags & ALLOC_CMA &&
|
|
zone_page_state(zone, NR_FREE_CMA_PAGES) >
|
|
zone_page_state(zone, NR_FREE_PAGES) / 2) {
|
|
page = __rmqueue_cma_fallback(zone, order);
|
|
if (page)
|
|
goto out;
|
|
}
|
|
}
|
|
retry:
|
|
page = __rmqueue_smallest(zone, order, migratetype);
|
|
if (unlikely(!page)) {
|
|
if (alloc_flags & ALLOC_CMA)
|
|
page = __rmqueue_cma_fallback(zone, order);
|
|
|
|
if (!page && __rmqueue_fallback(zone, order, migratetype,
|
|
alloc_flags))
|
|
goto retry;
|
|
}
|
|
out:
|
|
if (page)
|
|
trace_mm_page_alloc_zone_locked(page, order, migratetype);
|
|
return page;
|
|
}
|
|
|
|
/*
|
|
* Obtain a specified number of elements from the buddy allocator, all under
|
|
* a single hold of the lock, for efficiency. Add them to the supplied list.
|
|
* Returns the number of new pages which were placed at *list.
|
|
*/
|
|
static int rmqueue_bulk(struct zone *zone, unsigned int order,
|
|
unsigned long count, struct list_head *list,
|
|
int migratetype, unsigned int alloc_flags)
|
|
{
|
|
int i, alloced = 0;
|
|
|
|
spin_lock(&zone->lock);
|
|
for (i = 0; i < count; ++i) {
|
|
struct page *page = __rmqueue(zone, order, migratetype,
|
|
alloc_flags);
|
|
if (unlikely(page == NULL))
|
|
break;
|
|
|
|
if (unlikely(check_pcp_refill(page)))
|
|
continue;
|
|
|
|
/*
|
|
* Split buddy pages returned by expand() are received here in
|
|
* physical page order. The page is added to the tail of
|
|
* caller's list. From the callers perspective, the linked list
|
|
* is ordered by page number under some conditions. This is
|
|
* useful for IO devices that can forward direction from the
|
|
* head, thus also in the physical page order. This is useful
|
|
* for IO devices that can merge IO requests if the physical
|
|
* pages are ordered properly.
|
|
*/
|
|
list_add_tail(&page->lru, list);
|
|
alloced++;
|
|
if (is_migrate_cma(get_pcppage_migratetype(page)))
|
|
__mod_zone_page_state(zone, NR_FREE_CMA_PAGES,
|
|
-(1 << order));
|
|
}
|
|
|
|
/*
|
|
* i pages were removed from the buddy list even if some leak due
|
|
* to check_pcp_refill failing so adjust NR_FREE_PAGES based
|
|
* on i. Do not confuse with 'alloced' which is the number of
|
|
* pages added to the pcp list.
|
|
*/
|
|
__mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
|
|
spin_unlock(&zone->lock);
|
|
return alloced;
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA
|
|
/*
|
|
* Called from the vmstat counter updater to drain pagesets of this
|
|
* currently executing processor on remote nodes after they have
|
|
* expired.
|
|
*
|
|
* Note that this function must be called with the thread pinned to
|
|
* a single processor.
|
|
*/
|
|
void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
|
|
{
|
|
unsigned long flags;
|
|
int to_drain, batch;
|
|
|
|
local_irq_save(flags);
|
|
batch = READ_ONCE(pcp->batch);
|
|
to_drain = min(pcp->count, batch);
|
|
if (to_drain > 0)
|
|
free_pcppages_bulk(zone, to_drain, pcp);
|
|
local_irq_restore(flags);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Drain pcplists of the indicated processor and zone.
|
|
*
|
|
* The processor must either be the current processor and the
|
|
* thread pinned to the current processor or a processor that
|
|
* is not online.
|
|
*/
|
|
static void drain_pages_zone(unsigned int cpu, struct zone *zone)
|
|
{
|
|
unsigned long flags;
|
|
struct per_cpu_pageset *pset;
|
|
struct per_cpu_pages *pcp;
|
|
|
|
local_irq_save(flags);
|
|
pset = per_cpu_ptr(zone->pageset, cpu);
|
|
|
|
pcp = &pset->pcp;
|
|
if (pcp->count)
|
|
free_pcppages_bulk(zone, pcp->count, pcp);
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
/*
|
|
* Drain pcplists of all zones on the indicated processor.
|
|
*
|
|
* The processor must either be the current processor and the
|
|
* thread pinned to the current processor or a processor that
|
|
* is not online.
|
|
*/
|
|
static void drain_pages(unsigned int cpu)
|
|
{
|
|
struct zone *zone;
|
|
|
|
for_each_populated_zone(zone) {
|
|
drain_pages_zone(cpu, zone);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Spill all of this CPU's per-cpu pages back into the buddy allocator.
|
|
*
|
|
* The CPU has to be pinned. When zone parameter is non-NULL, spill just
|
|
* the single zone's pages.
|
|
*/
|
|
void drain_local_pages(struct zone *zone)
|
|
{
|
|
int cpu = smp_processor_id();
|
|
|
|
if (zone)
|
|
drain_pages_zone(cpu, zone);
|
|
else
|
|
drain_pages(cpu);
|
|
}
|
|
|
|
static void drain_local_pages_wq(struct work_struct *work)
|
|
{
|
|
struct pcpu_drain *drain;
|
|
|
|
drain = container_of(work, struct pcpu_drain, work);
|
|
|
|
/*
|
|
* drain_all_pages doesn't use proper cpu hotplug protection so
|
|
* we can race with cpu offline when the WQ can move this from
|
|
* a cpu pinned worker to an unbound one. We can operate on a different
|
|
* cpu which is allright but we also have to make sure to not move to
|
|
* a different one.
|
|
*/
|
|
preempt_disable();
|
|
drain_local_pages(drain->zone);
|
|
preempt_enable();
|
|
}
|
|
|
|
/*
|
|
* The implementation of drain_all_pages(), exposing an extra parameter to
|
|
* drain on all cpus.
|
|
*
|
|
* drain_all_pages() is optimized to only execute on cpus where pcplists are
|
|
* not empty. The check for non-emptiness can however race with a free to
|
|
* pcplist that has not yet increased the pcp->count from 0 to 1. Callers
|
|
* that need the guarantee that every CPU has drained can disable the
|
|
* optimizing racy check.
|
|
*/
|
|
static void __drain_all_pages(struct zone *zone, bool force_all_cpus)
|
|
{
|
|
int cpu;
|
|
|
|
/*
|
|
* Allocate in the BSS so we wont require allocation in
|
|
* direct reclaim path for CONFIG_CPUMASK_OFFSTACK=y
|
|
*/
|
|
static cpumask_t cpus_with_pcps;
|
|
|
|
/*
|
|
* Make sure nobody triggers this path before mm_percpu_wq is fully
|
|
* initialized.
|
|
*/
|
|
if (WARN_ON_ONCE(!mm_percpu_wq))
|
|
return;
|
|
|
|
/*
|
|
* Do not drain if one is already in progress unless it's specific to
|
|
* a zone. Such callers are primarily CMA and memory hotplug and need
|
|
* the drain to be complete when the call returns.
|
|
*/
|
|
if (unlikely(!mutex_trylock(&pcpu_drain_mutex))) {
|
|
if (!zone)
|
|
return;
|
|
mutex_lock(&pcpu_drain_mutex);
|
|
}
|
|
|
|
/*
|
|
* We don't care about racing with CPU hotplug event
|
|
* as offline notification will cause the notified
|
|
* cpu to drain that CPU pcps and on_each_cpu_mask
|
|
* disables preemption as part of its processing
|
|
*/
|
|
for_each_online_cpu(cpu) {
|
|
struct per_cpu_pageset *pcp;
|
|
struct zone *z;
|
|
bool has_pcps = false;
|
|
|
|
if (force_all_cpus) {
|
|
/*
|
|
* The pcp.count check is racy, some callers need a
|
|
* guarantee that no cpu is missed.
|
|
*/
|
|
has_pcps = true;
|
|
} else if (zone) {
|
|
pcp = per_cpu_ptr(zone->pageset, cpu);
|
|
if (pcp->pcp.count)
|
|
has_pcps = true;
|
|
} else {
|
|
for_each_populated_zone(z) {
|
|
pcp = per_cpu_ptr(z->pageset, cpu);
|
|
if (pcp->pcp.count) {
|
|
has_pcps = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (has_pcps)
|
|
cpumask_set_cpu(cpu, &cpus_with_pcps);
|
|
else
|
|
cpumask_clear_cpu(cpu, &cpus_with_pcps);
|
|
}
|
|
|
|
for_each_cpu(cpu, &cpus_with_pcps) {
|
|
struct pcpu_drain *drain = per_cpu_ptr(&pcpu_drain, cpu);
|
|
|
|
drain->zone = zone;
|
|
INIT_WORK(&drain->work, drain_local_pages_wq);
|
|
queue_work_on(cpu, mm_percpu_wq, &drain->work);
|
|
}
|
|
for_each_cpu(cpu, &cpus_with_pcps)
|
|
flush_work(&per_cpu_ptr(&pcpu_drain, cpu)->work);
|
|
|
|
mutex_unlock(&pcpu_drain_mutex);
|
|
}
|
|
|
|
/*
|
|
* Spill all the per-cpu pages from all CPUs back into the buddy allocator.
|
|
*
|
|
* When zone parameter is non-NULL, spill just the single zone's pages.
|
|
*
|
|
* Note that this can be extremely slow as the draining happens in a workqueue.
|
|
*/
|
|
void drain_all_pages(struct zone *zone)
|
|
{
|
|
__drain_all_pages(zone, false);
|
|
}
|
|
|
|
#ifdef CONFIG_HIBERNATION
|
|
|
|
/*
|
|
* Touch the watchdog for every WD_PAGE_COUNT pages.
|
|
*/
|
|
#define WD_PAGE_COUNT (128*1024)
|
|
|
|
void mark_free_pages(struct zone *zone)
|
|
{
|
|
unsigned long pfn, max_zone_pfn, page_count = WD_PAGE_COUNT;
|
|
unsigned long flags;
|
|
unsigned int order, t;
|
|
struct page *page;
|
|
|
|
if (zone_is_empty(zone))
|
|
return;
|
|
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
|
|
max_zone_pfn = zone_end_pfn(zone);
|
|
for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
|
|
if (pfn_valid(pfn)) {
|
|
page = pfn_to_page(pfn);
|
|
|
|
if (!--page_count) {
|
|
touch_nmi_watchdog();
|
|
page_count = WD_PAGE_COUNT;
|
|
}
|
|
|
|
if (page_zone(page) != zone)
|
|
continue;
|
|
|
|
if (!swsusp_page_is_forbidden(page))
|
|
swsusp_unset_page_free(page);
|
|
}
|
|
|
|
for_each_migratetype_order(order, t) {
|
|
list_for_each_entry(page,
|
|
&zone->free_area[order].free_list[t], lru) {
|
|
unsigned long i;
|
|
|
|
pfn = page_to_pfn(page);
|
|
for (i = 0; i < (1UL << order); i++) {
|
|
if (!--page_count) {
|
|
touch_nmi_watchdog();
|
|
page_count = WD_PAGE_COUNT;
|
|
}
|
|
swsusp_set_page_free(pfn_to_page(pfn + i));
|
|
}
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
}
|
|
#endif /* CONFIG_PM */
|
|
|
|
static bool free_unref_page_prepare(struct page *page, unsigned long pfn)
|
|
{
|
|
int migratetype;
|
|
|
|
if (!free_pcp_prepare(page))
|
|
return false;
|
|
|
|
migratetype = get_pfnblock_migratetype(page, pfn);
|
|
set_pcppage_migratetype(page, migratetype);
|
|
return true;
|
|
}
|
|
|
|
static void free_unref_page_commit(struct page *page, unsigned long pfn)
|
|
{
|
|
struct zone *zone = page_zone(page);
|
|
struct per_cpu_pages *pcp;
|
|
int migratetype;
|
|
|
|
migratetype = get_pcppage_migratetype(page);
|
|
__count_vm_event(PGFREE);
|
|
|
|
/*
|
|
* We only track unmovable, reclaimable and movable on pcp lists.
|
|
* Free ISOLATE pages back to the allocator because they are being
|
|
* offlined but treat HIGHATOMIC as movable pages so we can get those
|
|
* areas back if necessary. Otherwise, we may have to free
|
|
* excessively into the page allocator
|
|
*/
|
|
if (migratetype >= MIGRATE_PCPTYPES) {
|
|
if (unlikely(is_migrate_isolate(migratetype))) {
|
|
free_one_page(zone, page, pfn, 0, migratetype,
|
|
FPI_NONE);
|
|
return;
|
|
}
|
|
migratetype = MIGRATE_MOVABLE;
|
|
}
|
|
|
|
pcp = &this_cpu_ptr(zone->pageset)->pcp;
|
|
list_add(&page->lru, &pcp->lists[migratetype]);
|
|
pcp->count++;
|
|
if (pcp->count >= READ_ONCE(pcp->high))
|
|
free_pcppages_bulk(zone, READ_ONCE(pcp->batch), pcp);
|
|
}
|
|
|
|
/*
|
|
* Free a 0-order page
|
|
*/
|
|
void free_unref_page(struct page *page)
|
|
{
|
|
unsigned long flags;
|
|
unsigned long pfn = page_to_pfn(page);
|
|
|
|
if (!free_unref_page_prepare(page, pfn))
|
|
return;
|
|
|
|
local_irq_save(flags);
|
|
free_unref_page_commit(page, pfn);
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
/*
|
|
* Free a list of 0-order pages
|
|
*/
|
|
void free_unref_page_list(struct list_head *list)
|
|
{
|
|
struct page *page, *next;
|
|
unsigned long flags, pfn;
|
|
int batch_count = 0;
|
|
|
|
/* Prepare pages for freeing */
|
|
list_for_each_entry_safe(page, next, list, lru) {
|
|
pfn = page_to_pfn(page);
|
|
if (!free_unref_page_prepare(page, pfn))
|
|
list_del(&page->lru);
|
|
set_page_private(page, pfn);
|
|
}
|
|
|
|
local_irq_save(flags);
|
|
list_for_each_entry_safe(page, next, list, lru) {
|
|
unsigned long pfn = page_private(page);
|
|
|
|
set_page_private(page, 0);
|
|
trace_mm_page_free_batched(page);
|
|
free_unref_page_commit(page, pfn);
|
|
|
|
/*
|
|
* Guard against excessive IRQ disabled times when we get
|
|
* a large list of pages to free.
|
|
*/
|
|
if (++batch_count == SWAP_CLUSTER_MAX) {
|
|
local_irq_restore(flags);
|
|
batch_count = 0;
|
|
local_irq_save(flags);
|
|
}
|
|
}
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
/*
|
|
* split_page takes a non-compound higher-order page, and splits it into
|
|
* n (1<<order) sub-pages: page[0..n]
|
|
* Each sub-page must be freed individually.
|
|
*
|
|
* Note: this is probably too low level an operation for use in drivers.
|
|
* Please consult with lkml before using this in your driver.
|
|
*/
|
|
void split_page(struct page *page, unsigned int order)
|
|
{
|
|
int i;
|
|
|
|
VM_BUG_ON_PAGE(PageCompound(page), page);
|
|
VM_BUG_ON_PAGE(!page_count(page), page);
|
|
|
|
for (i = 1; i < (1 << order); i++)
|
|
set_page_refcounted(page + i);
|
|
split_page_owner(page, 1 << order);
|
|
split_page_memcg(page, 1 << order);
|
|
}
|
|
EXPORT_SYMBOL_GPL(split_page);
|
|
|
|
int __isolate_free_page(struct page *page, unsigned int order)
|
|
{
|
|
unsigned long watermark;
|
|
struct zone *zone;
|
|
int mt;
|
|
|
|
BUG_ON(!PageBuddy(page));
|
|
|
|
zone = page_zone(page);
|
|
mt = get_pageblock_migratetype(page);
|
|
|
|
if (!is_migrate_isolate(mt)) {
|
|
/*
|
|
* Obey watermarks as if the page was being allocated. We can
|
|
* emulate a high-order watermark check with a raised order-0
|
|
* watermark, because we already know our high-order page
|
|
* exists.
|
|
*/
|
|
watermark = zone->_watermark[WMARK_MIN] + (1UL << order);
|
|
if (!zone_watermark_ok(zone, 0, watermark, 0, ALLOC_CMA))
|
|
return 0;
|
|
|
|
__mod_zone_freepage_state(zone, -(1UL << order), mt);
|
|
}
|
|
|
|
/* Remove page from free list */
|
|
|
|
del_page_from_free_list(page, zone, order);
|
|
|
|
/*
|
|
* Set the pageblock if the isolated page is at least half of a
|
|
* pageblock
|
|
*/
|
|
if (order >= pageblock_order - 1) {
|
|
struct page *endpage = page + (1 << order) - 1;
|
|
for (; page < endpage; page += pageblock_nr_pages) {
|
|
int mt = get_pageblock_migratetype(page);
|
|
if (!is_migrate_isolate(mt) && !is_migrate_cma(mt)
|
|
&& !is_migrate_highatomic(mt))
|
|
set_pageblock_migratetype(page,
|
|
MIGRATE_MOVABLE);
|
|
}
|
|
}
|
|
|
|
|
|
return 1UL << order;
|
|
}
|
|
|
|
/**
|
|
* __putback_isolated_page - Return a now-isolated page back where we got it
|
|
* @page: Page that was isolated
|
|
* @order: Order of the isolated page
|
|
* @mt: The page's pageblock's migratetype
|
|
*
|
|
* This function is meant to return a page pulled from the free lists via
|
|
* __isolate_free_page back to the free lists they were pulled from.
|
|
*/
|
|
void __putback_isolated_page(struct page *page, unsigned int order, int mt)
|
|
{
|
|
struct zone *zone = page_zone(page);
|
|
|
|
/* zone lock should be held when this function is called */
|
|
lockdep_assert_held(&zone->lock);
|
|
|
|
/* Return isolated page to tail of freelist. */
|
|
__free_one_page(page, page_to_pfn(page), zone, order, mt,
|
|
FPI_SKIP_REPORT_NOTIFY | FPI_TO_TAIL);
|
|
}
|
|
|
|
/*
|
|
* Update NUMA hit/miss statistics
|
|
*
|
|
* Must be called with interrupts disabled.
|
|
*/
|
|
static inline void zone_statistics(struct zone *preferred_zone, struct zone *z)
|
|
{
|
|
#ifdef CONFIG_NUMA
|
|
enum numa_stat_item local_stat = NUMA_LOCAL;
|
|
|
|
/* skip numa counters update if numa stats is disabled */
|
|
if (!static_branch_likely(&vm_numa_stat_key))
|
|
return;
|
|
|
|
if (zone_to_nid(z) != numa_node_id())
|
|
local_stat = NUMA_OTHER;
|
|
|
|
if (zone_to_nid(z) == zone_to_nid(preferred_zone))
|
|
__inc_numa_state(z, NUMA_HIT);
|
|
else {
|
|
__inc_numa_state(z, NUMA_MISS);
|
|
__inc_numa_state(preferred_zone, NUMA_FOREIGN);
|
|
}
|
|
__inc_numa_state(z, local_stat);
|
|
#endif
|
|
}
|
|
|
|
/* Remove page from the per-cpu list, caller must protect the list */
|
|
static struct page *__rmqueue_pcplist(struct zone *zone, int migratetype,
|
|
unsigned int alloc_flags,
|
|
struct per_cpu_pages *pcp,
|
|
struct list_head *list)
|
|
{
|
|
struct page *page;
|
|
|
|
do {
|
|
if (list_empty(list)) {
|
|
pcp->count += rmqueue_bulk(zone, 0,
|
|
READ_ONCE(pcp->batch), list,
|
|
migratetype, alloc_flags);
|
|
if (unlikely(list_empty(list)))
|
|
return NULL;
|
|
}
|
|
|
|
page = list_first_entry(list, struct page, lru);
|
|
list_del(&page->lru);
|
|
pcp->count--;
|
|
} while (check_new_pcp(page));
|
|
|
|
return page;
|
|
}
|
|
|
|
/* Lock and remove page from the per-cpu list */
|
|
static struct page *rmqueue_pcplist(struct zone *preferred_zone,
|
|
struct zone *zone, gfp_t gfp_flags,
|
|
int migratetype, unsigned int alloc_flags)
|
|
{
|
|
struct per_cpu_pages *pcp;
|
|
struct list_head *list;
|
|
struct page *page;
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
pcp = &this_cpu_ptr(zone->pageset)->pcp;
|
|
list = &pcp->lists[migratetype];
|
|
page = __rmqueue_pcplist(zone, migratetype, alloc_flags, pcp, list);
|
|
if (page) {
|
|
__count_zid_vm_events(PGALLOC, page_zonenum(page), 1);
|
|
zone_statistics(preferred_zone, zone);
|
|
}
|
|
local_irq_restore(flags);
|
|
return page;
|
|
}
|
|
|
|
/*
|
|
* Allocate a page from the given zone. Use pcplists for order-0 allocations.
|
|
*/
|
|
static inline
|
|
struct page *rmqueue(struct zone *preferred_zone,
|
|
struct zone *zone, unsigned int order,
|
|
gfp_t gfp_flags, unsigned int alloc_flags,
|
|
int migratetype)
|
|
{
|
|
unsigned long flags;
|
|
struct page *page;
|
|
|
|
if (likely(order == 0)) {
|
|
/*
|
|
* MIGRATE_MOVABLE pcplist could have the pages on CMA area and
|
|
* we need to skip it when CMA area isn't allowed.
|
|
*/
|
|
if (!IS_ENABLED(CONFIG_CMA) || alloc_flags & ALLOC_CMA ||
|
|
migratetype != MIGRATE_MOVABLE) {
|
|
page = rmqueue_pcplist(preferred_zone, zone, gfp_flags,
|
|
migratetype, alloc_flags);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* We most definitely don't want callers attempting to
|
|
* allocate greater than order-1 page units with __GFP_NOFAIL.
|
|
*/
|
|
WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1));
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
|
|
do {
|
|
page = NULL;
|
|
/*
|
|
* order-0 request can reach here when the pcplist is skipped
|
|
* due to non-CMA allocation context. HIGHATOMIC area is
|
|
* reserved for high-order atomic allocation, so order-0
|
|
* request should skip it.
|
|
*/
|
|
if (order > 0 && alloc_flags & ALLOC_HARDER) {
|
|
page = __rmqueue_smallest(zone, order, MIGRATE_HIGHATOMIC);
|
|
if (page)
|
|
trace_mm_page_alloc_zone_locked(page, order, migratetype);
|
|
}
|
|
if (!page)
|
|
page = __rmqueue(zone, order, migratetype, alloc_flags);
|
|
} while (page && check_new_pages(page, order));
|
|
spin_unlock(&zone->lock);
|
|
if (!page)
|
|
goto failed;
|
|
__mod_zone_freepage_state(zone, -(1 << order),
|
|
get_pcppage_migratetype(page));
|
|
|
|
__count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
|
|
zone_statistics(preferred_zone, zone);
|
|
local_irq_restore(flags);
|
|
|
|
out:
|
|
/* Separate test+clear to avoid unnecessary atomics */
|
|
if (test_bit(ZONE_BOOSTED_WATERMARK, &zone->flags)) {
|
|
clear_bit(ZONE_BOOSTED_WATERMARK, &zone->flags);
|
|
wakeup_kswapd(zone, 0, 0, zone_idx(zone));
|
|
}
|
|
|
|
VM_BUG_ON_PAGE(page && bad_range(zone, page), page);
|
|
return page;
|
|
|
|
failed:
|
|
local_irq_restore(flags);
|
|
return NULL;
|
|
}
|
|
|
|
#ifdef CONFIG_FAIL_PAGE_ALLOC
|
|
|
|
static struct {
|
|
struct fault_attr attr;
|
|
|
|
bool ignore_gfp_highmem;
|
|
bool ignore_gfp_reclaim;
|
|
u32 min_order;
|
|
} fail_page_alloc = {
|
|
.attr = FAULT_ATTR_INITIALIZER,
|
|
.ignore_gfp_reclaim = true,
|
|
.ignore_gfp_highmem = true,
|
|
.min_order = 1,
|
|
};
|
|
|
|
static int __init setup_fail_page_alloc(char *str)
|
|
{
|
|
return setup_fault_attr(&fail_page_alloc.attr, str);
|
|
}
|
|
__setup("fail_page_alloc=", setup_fail_page_alloc);
|
|
|
|
static bool __should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
|
|
{
|
|
if (order < fail_page_alloc.min_order)
|
|
return false;
|
|
if (gfp_mask & __GFP_NOFAIL)
|
|
return false;
|
|
if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM))
|
|
return false;
|
|
if (fail_page_alloc.ignore_gfp_reclaim &&
|
|
(gfp_mask & __GFP_DIRECT_RECLAIM))
|
|
return false;
|
|
|
|
return should_fail(&fail_page_alloc.attr, 1 << order);
|
|
}
|
|
|
|
#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
|
|
|
|
static int __init fail_page_alloc_debugfs(void)
|
|
{
|
|
umode_t mode = S_IFREG | 0600;
|
|
struct dentry *dir;
|
|
|
|
dir = fault_create_debugfs_attr("fail_page_alloc", NULL,
|
|
&fail_page_alloc.attr);
|
|
|
|
debugfs_create_bool("ignore-gfp-wait", mode, dir,
|
|
&fail_page_alloc.ignore_gfp_reclaim);
|
|
debugfs_create_bool("ignore-gfp-highmem", mode, dir,
|
|
&fail_page_alloc.ignore_gfp_highmem);
|
|
debugfs_create_u32("min-order", mode, dir, &fail_page_alloc.min_order);
|
|
|
|
return 0;
|
|
}
|
|
|
|
late_initcall(fail_page_alloc_debugfs);
|
|
|
|
#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
|
|
|
|
#else /* CONFIG_FAIL_PAGE_ALLOC */
|
|
|
|
static inline bool __should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
#endif /* CONFIG_FAIL_PAGE_ALLOC */
|
|
|
|
noinline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
|
|
{
|
|
return __should_fail_alloc_page(gfp_mask, order);
|
|
}
|
|
ALLOW_ERROR_INJECTION(should_fail_alloc_page, TRUE);
|
|
|
|
static inline long __zone_watermark_unusable_free(struct zone *z,
|
|
unsigned int order, unsigned int alloc_flags)
|
|
{
|
|
const bool alloc_harder = (alloc_flags & (ALLOC_HARDER|ALLOC_OOM));
|
|
long unusable_free = (1 << order) - 1;
|
|
|
|
/*
|
|
* If the caller does not have rights to ALLOC_HARDER then subtract
|
|
* the high-atomic reserves. This will over-estimate the size of the
|
|
* atomic reserve but it avoids a search.
|
|
*/
|
|
if (likely(!alloc_harder))
|
|
unusable_free += z->nr_reserved_highatomic;
|
|
|
|
#ifdef CONFIG_CMA
|
|
/* If allocation can't use CMA areas don't use free CMA pages */
|
|
if (!(alloc_flags & ALLOC_CMA))
|
|
unusable_free += zone_page_state(z, NR_FREE_CMA_PAGES);
|
|
#endif
|
|
|
|
return unusable_free;
|
|
}
|
|
|
|
/*
|
|
* Return true if free base pages are above 'mark'. For high-order checks it
|
|
* will return true of the order-0 watermark is reached and there is at least
|
|
* one free page of a suitable size. Checking now avoids taking the zone lock
|
|
* to check in the allocation paths if no pages are free.
|
|
*/
|
|
bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
|
|
int highest_zoneidx, unsigned int alloc_flags,
|
|
long free_pages)
|
|
{
|
|
long min = mark;
|
|
int o;
|
|
const bool alloc_harder = (alloc_flags & (ALLOC_HARDER|ALLOC_OOM));
|
|
|
|
/* free_pages may go negative - that's OK */
|
|
free_pages -= __zone_watermark_unusable_free(z, order, alloc_flags);
|
|
|
|
if (alloc_flags & ALLOC_HIGH)
|
|
min -= min / 2;
|
|
|
|
if (unlikely(alloc_harder)) {
|
|
/*
|
|
* OOM victims can try even harder than normal ALLOC_HARDER
|
|
* users on the grounds that it's definitely going to be in
|
|
* the exit path shortly and free memory. Any allocation it
|
|
* makes during the free path will be small and short-lived.
|
|
*/
|
|
if (alloc_flags & ALLOC_OOM)
|
|
min -= min / 2;
|
|
else
|
|
min -= min / 4;
|
|
}
|
|
|
|
/*
|
|
* Check watermarks for an order-0 allocation request. If these
|
|
* are not met, then a high-order request also cannot go ahead
|
|
* even if a suitable page happened to be free.
|
|
*/
|
|
if (free_pages <= min + z->lowmem_reserve[highest_zoneidx])
|
|
return false;
|
|
|
|
/* If this is an order-0 request then the watermark is fine */
|
|
if (!order)
|
|
return true;
|
|
|
|
/* For a high-order request, check at least one suitable page is free */
|
|
for (o = order; o < MAX_ORDER; o++) {
|
|
struct free_area *area = &z->free_area[o];
|
|
int mt;
|
|
|
|
if (!area->nr_free)
|
|
continue;
|
|
|
|
for (mt = 0; mt < MIGRATE_PCPTYPES; mt++) {
|
|
if (!free_area_empty(area, mt))
|
|
return true;
|
|
}
|
|
|
|
#ifdef CONFIG_CMA
|
|
if ((alloc_flags & ALLOC_CMA) &&
|
|
!free_area_empty(area, MIGRATE_CMA)) {
|
|
return true;
|
|
}
|
|
#endif
|
|
if (alloc_harder && !free_area_empty(area, MIGRATE_HIGHATOMIC))
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
|
|
int highest_zoneidx, unsigned int alloc_flags)
|
|
{
|
|
return __zone_watermark_ok(z, order, mark, highest_zoneidx, alloc_flags,
|
|
zone_page_state(z, NR_FREE_PAGES));
|
|
}
|
|
|
|
static inline bool zone_watermark_fast(struct zone *z, unsigned int order,
|
|
unsigned long mark, int highest_zoneidx,
|
|
unsigned int alloc_flags, gfp_t gfp_mask)
|
|
{
|
|
long free_pages;
|
|
|
|
free_pages = zone_page_state(z, NR_FREE_PAGES);
|
|
|
|
/*
|
|
* Fast check for order-0 only. If this fails then the reserves
|
|
* need to be calculated.
|
|
*/
|
|
if (!order) {
|
|
long fast_free;
|
|
|
|
fast_free = free_pages;
|
|
fast_free -= __zone_watermark_unusable_free(z, 0, alloc_flags);
|
|
if (fast_free > mark + z->lowmem_reserve[highest_zoneidx])
|
|
return true;
|
|
}
|
|
|
|
if (__zone_watermark_ok(z, order, mark, highest_zoneidx, alloc_flags,
|
|
free_pages))
|
|
return true;
|
|
/*
|
|
* Ignore watermark boosting for GFP_ATOMIC order-0 allocations
|
|
* when checking the min watermark. The min watermark is the
|
|
* point where boosting is ignored so that kswapd is woken up
|
|
* when below the low watermark.
|
|
*/
|
|
if (unlikely(!order && (gfp_mask & __GFP_ATOMIC) && z->watermark_boost
|
|
&& ((alloc_flags & ALLOC_WMARK_MASK) == WMARK_MIN))) {
|
|
mark = z->_watermark[WMARK_MIN];
|
|
return __zone_watermark_ok(z, order, mark, highest_zoneidx,
|
|
alloc_flags, free_pages);
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
bool zone_watermark_ok_safe(struct zone *z, unsigned int order,
|
|
unsigned long mark, int highest_zoneidx)
|
|
{
|
|
long free_pages = zone_page_state(z, NR_FREE_PAGES);
|
|
|
|
if (z->percpu_drift_mark && free_pages < z->percpu_drift_mark)
|
|
free_pages = zone_page_state_snapshot(z, NR_FREE_PAGES);
|
|
|
|
return __zone_watermark_ok(z, order, mark, highest_zoneidx, 0,
|
|
free_pages);
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA
|
|
static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone)
|
|
{
|
|
return node_distance(zone_to_nid(local_zone), zone_to_nid(zone)) <=
|
|
node_reclaim_distance;
|
|
}
|
|
#else /* CONFIG_NUMA */
|
|
static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone)
|
|
{
|
|
return true;
|
|
}
|
|
#endif /* CONFIG_NUMA */
|
|
|
|
/*
|
|
* The restriction on ZONE_DMA32 as being a suitable zone to use to avoid
|
|
* fragmentation is subtle. If the preferred zone was HIGHMEM then
|
|
* premature use of a lower zone may cause lowmem pressure problems that
|
|
* are worse than fragmentation. If the next zone is ZONE_DMA then it is
|
|
* probably too small. It only makes sense to spread allocations to avoid
|
|
* fragmentation between the Normal and DMA32 zones.
|
|
*/
|
|
static inline unsigned int
|
|
alloc_flags_nofragment(struct zone *zone, gfp_t gfp_mask)
|
|
{
|
|
unsigned int alloc_flags;
|
|
|
|
/*
|
|
* __GFP_KSWAPD_RECLAIM is assumed to be the same as ALLOC_KSWAPD
|
|
* to save a branch.
|
|
*/
|
|
alloc_flags = (__force int) (gfp_mask & __GFP_KSWAPD_RECLAIM);
|
|
|
|
#ifdef CONFIG_ZONE_DMA32
|
|
if (!zone)
|
|
return alloc_flags;
|
|
|
|
if (zone_idx(zone) != ZONE_NORMAL)
|
|
return alloc_flags;
|
|
|
|
/*
|
|
* If ZONE_DMA32 exists, assume it is the one after ZONE_NORMAL and
|
|
* the pointer is within zone->zone_pgdat->node_zones[]. Also assume
|
|
* on UMA that if Normal is populated then so is DMA32.
|
|
*/
|
|
BUILD_BUG_ON(ZONE_NORMAL - ZONE_DMA32 != 1);
|
|
if (nr_online_nodes > 1 && !populated_zone(--zone))
|
|
return alloc_flags;
|
|
|
|
alloc_flags |= ALLOC_NOFRAGMENT;
|
|
#endif /* CONFIG_ZONE_DMA32 */
|
|
return alloc_flags;
|
|
}
|
|
|
|
static inline unsigned int current_alloc_flags(gfp_t gfp_mask,
|
|
unsigned int alloc_flags)
|
|
{
|
|
#ifdef CONFIG_CMA
|
|
unsigned int pflags = current->flags;
|
|
|
|
if (!(pflags & PF_MEMALLOC_NOCMA) &&
|
|
gfp_migratetype(gfp_mask) == MIGRATE_MOVABLE)
|
|
alloc_flags |= ALLOC_CMA;
|
|
|
|
#endif
|
|
return alloc_flags;
|
|
}
|
|
|
|
/*
|
|
* get_page_from_freelist goes through the zonelist trying to allocate
|
|
* a page.
|
|
*/
|
|
static struct page *
|
|
get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags,
|
|
const struct alloc_context *ac)
|
|
{
|
|
struct zoneref *z;
|
|
struct zone *zone;
|
|
struct pglist_data *last_pgdat_dirty_limit = NULL;
|
|
bool no_fallback;
|
|
|
|
retry:
|
|
/*
|
|
* Scan zonelist, looking for a zone with enough free.
|
|
* See also __cpuset_node_allowed() comment in kernel/cpuset.c.
|
|
*/
|
|
no_fallback = alloc_flags & ALLOC_NOFRAGMENT;
|
|
z = ac->preferred_zoneref;
|
|
for_next_zone_zonelist_nodemask(zone, z, ac->highest_zoneidx,
|
|
ac->nodemask) {
|
|
struct page *page;
|
|
unsigned long mark;
|
|
|
|
if (cpusets_enabled() &&
|
|
(alloc_flags & ALLOC_CPUSET) &&
|
|
!__cpuset_zone_allowed(zone, gfp_mask))
|
|
continue;
|
|
/*
|
|
* When allocating a page cache page for writing, we
|
|
* want to get it from a node that is within its dirty
|
|
* limit, such that no single node holds more than its
|
|
* proportional share of globally allowed dirty pages.
|
|
* The dirty limits take into account the node's
|
|
* lowmem reserves and high watermark so that kswapd
|
|
* should be able to balance it without having to
|
|
* write pages from its LRU list.
|
|
*
|
|
* XXX: For now, allow allocations to potentially
|
|
* exceed the per-node dirty limit in the slowpath
|
|
* (spread_dirty_pages unset) before going into reclaim,
|
|
* which is important when on a NUMA setup the allowed
|
|
* nodes are together not big enough to reach the
|
|
* global limit. The proper fix for these situations
|
|
* will require awareness of nodes in the
|
|
* dirty-throttling and the flusher threads.
|
|
*/
|
|
if (ac->spread_dirty_pages) {
|
|
if (last_pgdat_dirty_limit == zone->zone_pgdat)
|
|
continue;
|
|
|
|
if (!node_dirty_ok(zone->zone_pgdat)) {
|
|
last_pgdat_dirty_limit = zone->zone_pgdat;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
if (no_fallback && nr_online_nodes > 1 &&
|
|
zone != ac->preferred_zoneref->zone) {
|
|
int local_nid;
|
|
|
|
/*
|
|
* If moving to a remote node, retry but allow
|
|
* fragmenting fallbacks. Locality is more important
|
|
* than fragmentation avoidance.
|
|
*/
|
|
local_nid = zone_to_nid(ac->preferred_zoneref->zone);
|
|
if (zone_to_nid(zone) != local_nid) {
|
|
alloc_flags &= ~ALLOC_NOFRAGMENT;
|
|
goto retry;
|
|
}
|
|
}
|
|
|
|
mark = wmark_pages(zone, alloc_flags & ALLOC_WMARK_MASK);
|
|
if (!zone_watermark_fast(zone, order, mark,
|
|
ac->highest_zoneidx, alloc_flags,
|
|
gfp_mask)) {
|
|
int ret;
|
|
|
|
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
|
|
/*
|
|
* Watermark failed for this zone, but see if we can
|
|
* grow this zone if it contains deferred pages.
|
|
*/
|
|
if (static_branch_unlikely(&deferred_pages)) {
|
|
if (_deferred_grow_zone(zone, order))
|
|
goto try_this_zone;
|
|
}
|
|
#endif
|
|
/* Checked here to keep the fast path fast */
|
|
BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);
|
|
if (alloc_flags & ALLOC_NO_WATERMARKS)
|
|
goto try_this_zone;
|
|
|
|
if (node_reclaim_mode == 0 ||
|
|
!zone_allows_reclaim(ac->preferred_zoneref->zone, zone))
|
|
continue;
|
|
|
|
ret = node_reclaim(zone->zone_pgdat, gfp_mask, order);
|
|
switch (ret) {
|
|
case NODE_RECLAIM_NOSCAN:
|
|
/* did not scan */
|
|
continue;
|
|
case NODE_RECLAIM_FULL:
|
|
/* scanned but unreclaimable */
|
|
continue;
|
|
default:
|
|
/* did we reclaim enough */
|
|
if (zone_watermark_ok(zone, order, mark,
|
|
ac->highest_zoneidx, alloc_flags))
|
|
goto try_this_zone;
|
|
|
|
continue;
|
|
}
|
|
}
|
|
|
|
try_this_zone:
|
|
page = rmqueue(ac->preferred_zoneref->zone, zone, order,
|
|
gfp_mask, alloc_flags, ac->migratetype);
|
|
if (page) {
|
|
prep_new_page(page, order, gfp_mask, alloc_flags);
|
|
|
|
/*
|
|
* If this is a high-order atomic allocation then check
|
|
* if the pageblock should be reserved for the future
|
|
*/
|
|
if (unlikely(order && (alloc_flags & ALLOC_HARDER)))
|
|
reserve_highatomic_pageblock(page, zone, order);
|
|
|
|
return page;
|
|
} else {
|
|
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
|
|
/* Try again if zone has deferred pages */
|
|
if (static_branch_unlikely(&deferred_pages)) {
|
|
if (_deferred_grow_zone(zone, order))
|
|
goto try_this_zone;
|
|
}
|
|
#endif
|
|
}
|
|
}
|
|
|
|
/*
|
|
* It's possible on a UMA machine to get through all zones that are
|
|
* fragmented. If avoiding fragmentation, reset and try again.
|
|
*/
|
|
if (no_fallback) {
|
|
alloc_flags &= ~ALLOC_NOFRAGMENT;
|
|
goto retry;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void warn_alloc_show_mem(gfp_t gfp_mask, nodemask_t *nodemask)
|
|
{
|
|
unsigned int filter = SHOW_MEM_FILTER_NODES;
|
|
|
|
/*
|
|
* This documents exceptions given to allocations in certain
|
|
* contexts that are allowed to allocate outside current's set
|
|
* of allowed nodes.
|
|
*/
|
|
if (!(gfp_mask & __GFP_NOMEMALLOC))
|
|
if (tsk_is_oom_victim(current) ||
|
|
(current->flags & (PF_MEMALLOC | PF_EXITING)))
|
|
filter &= ~SHOW_MEM_FILTER_NODES;
|
|
if (in_interrupt() || !(gfp_mask & __GFP_DIRECT_RECLAIM))
|
|
filter &= ~SHOW_MEM_FILTER_NODES;
|
|
|
|
show_mem(filter, nodemask);
|
|
}
|
|
|
|
void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...)
|
|
{
|
|
struct va_format vaf;
|
|
va_list args;
|
|
static DEFINE_RATELIMIT_STATE(nopage_rs, 10*HZ, 1);
|
|
|
|
if ((gfp_mask & __GFP_NOWARN) || !__ratelimit(&nopage_rs))
|
|
return;
|
|
|
|
va_start(args, fmt);
|
|
vaf.fmt = fmt;
|
|
vaf.va = &args;
|
|
pr_warn("%s: %pV, mode:%#x(%pGg), nodemask=%*pbl",
|
|
current->comm, &vaf, gfp_mask, &gfp_mask,
|
|
nodemask_pr_args(nodemask));
|
|
va_end(args);
|
|
|
|
cpuset_print_current_mems_allowed();
|
|
pr_cont("\n");
|
|
dump_stack();
|
|
warn_alloc_show_mem(gfp_mask, nodemask);
|
|
}
|
|
|
|
static inline struct page *
|
|
__alloc_pages_cpuset_fallback(gfp_t gfp_mask, unsigned int order,
|
|
unsigned int alloc_flags,
|
|
const struct alloc_context *ac)
|
|
{
|
|
struct page *page;
|
|
|
|
page = get_page_from_freelist(gfp_mask, order,
|
|
alloc_flags|ALLOC_CPUSET, ac);
|
|
/*
|
|
* fallback to ignore cpuset restriction if our nodes
|
|
* are depleted
|
|
*/
|
|
if (!page)
|
|
page = get_page_from_freelist(gfp_mask, order,
|
|
alloc_flags, ac);
|
|
|
|
return page;
|
|
}
|
|
|
|
static inline struct page *
|
|
__alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
|
|
const struct alloc_context *ac, unsigned long *did_some_progress)
|
|
{
|
|
struct oom_control oc = {
|
|
.zonelist = ac->zonelist,
|
|
.nodemask = ac->nodemask,
|
|
.memcg = NULL,
|
|
.gfp_mask = gfp_mask,
|
|
.order = order,
|
|
};
|
|
struct page *page;
|
|
|
|
*did_some_progress = 0;
|
|
|
|
/*
|
|
* Acquire the oom lock. If that fails, somebody else is
|
|
* making progress for us.
|
|
*/
|
|
if (!mutex_trylock(&oom_lock)) {
|
|
*did_some_progress = 1;
|
|
schedule_timeout_uninterruptible(1);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Go through the zonelist yet one more time, keep very high watermark
|
|
* here, this is only to catch a parallel oom killing, we must fail if
|
|
* we're still under heavy pressure. But make sure that this reclaim
|
|
* attempt shall not depend on __GFP_DIRECT_RECLAIM && !__GFP_NORETRY
|
|
* allocation which will never fail due to oom_lock already held.
|
|
*/
|
|
page = get_page_from_freelist((gfp_mask | __GFP_HARDWALL) &
|
|
~__GFP_DIRECT_RECLAIM, order,
|
|
ALLOC_WMARK_HIGH|ALLOC_CPUSET, ac);
|
|
if (page)
|
|
goto out;
|
|
|
|
/* Coredumps can quickly deplete all memory reserves */
|
|
if (current->flags & PF_DUMPCORE)
|
|
goto out;
|
|
/* The OOM killer will not help higher order allocs */
|
|
if (order > PAGE_ALLOC_COSTLY_ORDER)
|
|
goto out;
|
|
/*
|
|
* We have already exhausted all our reclaim opportunities without any
|
|
* success so it is time to admit defeat. We will skip the OOM killer
|
|
* because it is very likely that the caller has a more reasonable
|
|
* fallback than shooting a random task.
|
|
*
|
|
* The OOM killer may not free memory on a specific node.
|
|
*/
|
|
if (gfp_mask & (__GFP_RETRY_MAYFAIL | __GFP_THISNODE))
|
|
goto out;
|
|
/* The OOM killer does not needlessly kill tasks for lowmem */
|
|
if (ac->highest_zoneidx < ZONE_NORMAL)
|
|
goto out;
|
|
if (pm_suspended_storage())
|
|
goto out;
|
|
/*
|
|
* XXX: GFP_NOFS allocations should rather fail than rely on
|
|
* other request to make a forward progress.
|
|
* We are in an unfortunate situation where out_of_memory cannot
|
|
* do much for this context but let's try it to at least get
|
|
* access to memory reserved if the current task is killed (see
|
|
* out_of_memory). Once filesystems are ready to handle allocation
|
|
* failures more gracefully we should just bail out here.
|
|
*/
|
|
|
|
/* Exhausted what can be done so it's blame time */
|
|
if (out_of_memory(&oc) || WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL)) {
|
|
*did_some_progress = 1;
|
|
|
|
/*
|
|
* Help non-failing allocations by giving them access to memory
|
|
* reserves
|
|
*/
|
|
if (gfp_mask & __GFP_NOFAIL)
|
|
page = __alloc_pages_cpuset_fallback(gfp_mask, order,
|
|
ALLOC_NO_WATERMARKS, ac);
|
|
}
|
|
out:
|
|
mutex_unlock(&oom_lock);
|
|
return page;
|
|
}
|
|
|
|
/*
|
|
* Maximum number of compaction retries wit a progress before OOM
|
|
* killer is consider as the only way to move forward.
|
|
*/
|
|
#define MAX_COMPACT_RETRIES 16
|
|
|
|
#ifdef CONFIG_COMPACTION
|
|
/* Try memory compaction for high-order allocations before reclaim */
|
|
static struct page *
|
|
__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
|
|
unsigned int alloc_flags, const struct alloc_context *ac,
|
|
enum compact_priority prio, enum compact_result *compact_result)
|
|
{
|
|
struct page *page = NULL;
|
|
unsigned long pflags;
|
|
unsigned int noreclaim_flag;
|
|
|
|
if (!order)
|
|
return NULL;
|
|
|
|
psi_memstall_enter(&pflags);
|
|
noreclaim_flag = memalloc_noreclaim_save();
|
|
|
|
*compact_result = try_to_compact_pages(gfp_mask, order, alloc_flags, ac,
|
|
prio, &page);
|
|
|
|
memalloc_noreclaim_restore(noreclaim_flag);
|
|
psi_memstall_leave(&pflags);
|
|
|
|
/*
|
|
* At least in one zone compaction wasn't deferred or skipped, so let's
|
|
* count a compaction stall
|
|
*/
|
|
count_vm_event(COMPACTSTALL);
|
|
|
|
/* Prep a captured page if available */
|
|
if (page)
|
|
prep_new_page(page, order, gfp_mask, alloc_flags);
|
|
|
|
/* Try get a page from the freelist if available */
|
|
if (!page)
|
|
page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac);
|
|
|
|
if (page) {
|
|
struct zone *zone = page_zone(page);
|
|
|
|
zone->compact_blockskip_flush = false;
|
|
compaction_defer_reset(zone, order, true);
|
|
count_vm_event(COMPACTSUCCESS);
|
|
return page;
|
|
}
|
|
|
|
/*
|
|
* It's bad if compaction run occurs and fails. The most likely reason
|
|
* is that pages exist, but not enough to satisfy watermarks.
|
|
*/
|
|
count_vm_event(COMPACTFAIL);
|
|
|
|
cond_resched();
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static inline bool
|
|
should_compact_retry(struct alloc_context *ac, int order, int alloc_flags,
|
|
enum compact_result compact_result,
|
|
enum compact_priority *compact_priority,
|
|
int *compaction_retries)
|
|
{
|
|
int max_retries = MAX_COMPACT_RETRIES;
|
|
int min_priority;
|
|
bool ret = false;
|
|
int retries = *compaction_retries;
|
|
enum compact_priority priority = *compact_priority;
|
|
|
|
if (!order)
|
|
return false;
|
|
|
|
if (compaction_made_progress(compact_result))
|
|
(*compaction_retries)++;
|
|
|
|
/*
|
|
* compaction considers all the zone as desperately out of memory
|
|
* so it doesn't really make much sense to retry except when the
|
|
* failure could be caused by insufficient priority
|
|
*/
|
|
if (compaction_failed(compact_result))
|
|
goto check_priority;
|
|
|
|
/*
|
|
* compaction was skipped because there are not enough order-0 pages
|
|
* to work with, so we retry only if it looks like reclaim can help.
|
|
*/
|
|
if (compaction_needs_reclaim(compact_result)) {
|
|
ret = compaction_zonelist_suitable(ac, order, alloc_flags);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* make sure the compaction wasn't deferred or didn't bail out early
|
|
* due to locks contention before we declare that we should give up.
|
|
* But the next retry should use a higher priority if allowed, so
|
|
* we don't just keep bailing out endlessly.
|
|
*/
|
|
if (compaction_withdrawn(compact_result)) {
|
|
goto check_priority;
|
|
}
|
|
|
|
/*
|
|
* !costly requests are much more important than __GFP_RETRY_MAYFAIL
|
|
* costly ones because they are de facto nofail and invoke OOM
|
|
* killer to move on while costly can fail and users are ready
|
|
* to cope with that. 1/4 retries is rather arbitrary but we
|
|
* would need much more detailed feedback from compaction to
|
|
* make a better decision.
|
|
*/
|
|
if (order > PAGE_ALLOC_COSTLY_ORDER)
|
|
max_retries /= 4;
|
|
if (*compaction_retries <= max_retries) {
|
|
ret = true;
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Make sure there are attempts at the highest priority if we exhausted
|
|
* all retries or failed at the lower priorities.
|
|
*/
|
|
check_priority:
|
|
min_priority = (order > PAGE_ALLOC_COSTLY_ORDER) ?
|
|
MIN_COMPACT_COSTLY_PRIORITY : MIN_COMPACT_PRIORITY;
|
|
|
|
if (*compact_priority > min_priority) {
|
|
(*compact_priority)--;
|
|
*compaction_retries = 0;
|
|
ret = true;
|
|
}
|
|
out:
|
|
trace_compact_retry(order, priority, compact_result, retries, max_retries, ret);
|
|
return ret;
|
|
}
|
|
#else
|
|
static inline struct page *
|
|
__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
|
|
unsigned int alloc_flags, const struct alloc_context *ac,
|
|
enum compact_priority prio, enum compact_result *compact_result)
|
|
{
|
|
*compact_result = COMPACT_SKIPPED;
|
|
return NULL;
|
|
}
|
|
|
|
static inline bool
|
|
should_compact_retry(struct alloc_context *ac, unsigned int order, int alloc_flags,
|
|
enum compact_result compact_result,
|
|
enum compact_priority *compact_priority,
|
|
int *compaction_retries)
|
|
{
|
|
struct zone *zone;
|
|
struct zoneref *z;
|
|
|
|
if (!order || order > PAGE_ALLOC_COSTLY_ORDER)
|
|
return false;
|
|
|
|
/*
|
|
* There are setups with compaction disabled which would prefer to loop
|
|
* inside the allocator rather than hit the oom killer prematurely.
|
|
* Let's give them a good hope and keep retrying while the order-0
|
|
* watermarks are OK.
|
|
*/
|
|
for_each_zone_zonelist_nodemask(zone, z, ac->zonelist,
|
|
ac->highest_zoneidx, ac->nodemask) {
|
|
if (zone_watermark_ok(zone, 0, min_wmark_pages(zone),
|
|
ac->highest_zoneidx, alloc_flags))
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
#endif /* CONFIG_COMPACTION */
|
|
|
|
#ifdef CONFIG_LOCKDEP
|
|
static struct lockdep_map __fs_reclaim_map =
|
|
STATIC_LOCKDEP_MAP_INIT("fs_reclaim", &__fs_reclaim_map);
|
|
|
|
static bool __need_reclaim(gfp_t gfp_mask)
|
|
{
|
|
/* no reclaim without waiting on it */
|
|
if (!(gfp_mask & __GFP_DIRECT_RECLAIM))
|
|
return false;
|
|
|
|
/* this guy won't enter reclaim */
|
|
if (current->flags & PF_MEMALLOC)
|
|
return false;
|
|
|
|
if (gfp_mask & __GFP_NOLOCKDEP)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
void __fs_reclaim_acquire(void)
|
|
{
|
|
lock_map_acquire(&__fs_reclaim_map);
|
|
}
|
|
|
|
void __fs_reclaim_release(void)
|
|
{
|
|
lock_map_release(&__fs_reclaim_map);
|
|
}
|
|
|
|
void fs_reclaim_acquire(gfp_t gfp_mask)
|
|
{
|
|
gfp_mask = current_gfp_context(gfp_mask);
|
|
|
|
if (__need_reclaim(gfp_mask)) {
|
|
if (gfp_mask & __GFP_FS)
|
|
__fs_reclaim_acquire();
|
|
|
|
#ifdef CONFIG_MMU_NOTIFIER
|
|
lock_map_acquire(&__mmu_notifier_invalidate_range_start_map);
|
|
lock_map_release(&__mmu_notifier_invalidate_range_start_map);
|
|
#endif
|
|
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(fs_reclaim_acquire);
|
|
|
|
void fs_reclaim_release(gfp_t gfp_mask)
|
|
{
|
|
gfp_mask = current_gfp_context(gfp_mask);
|
|
|
|
if (__need_reclaim(gfp_mask)) {
|
|
if (gfp_mask & __GFP_FS)
|
|
__fs_reclaim_release();
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(fs_reclaim_release);
|
|
#endif
|
|
|
|
/* Perform direct synchronous page reclaim */
|
|
static unsigned long
|
|
__perform_reclaim(gfp_t gfp_mask, unsigned int order,
|
|
const struct alloc_context *ac)
|
|
{
|
|
unsigned int noreclaim_flag;
|
|
unsigned long pflags, progress;
|
|
|
|
cond_resched();
|
|
|
|
/* We now go into synchronous reclaim */
|
|
cpuset_memory_pressure_bump();
|
|
psi_memstall_enter(&pflags);
|
|
fs_reclaim_acquire(gfp_mask);
|
|
noreclaim_flag = memalloc_noreclaim_save();
|
|
|
|
progress = try_to_free_pages(ac->zonelist, order, gfp_mask,
|
|
ac->nodemask);
|
|
|
|
memalloc_noreclaim_restore(noreclaim_flag);
|
|
fs_reclaim_release(gfp_mask);
|
|
psi_memstall_leave(&pflags);
|
|
|
|
cond_resched();
|
|
|
|
return progress;
|
|
}
|
|
|
|
/* The really slow allocator path where we enter direct reclaim */
|
|
static inline struct page *
|
|
__alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
|
|
unsigned int alloc_flags, const struct alloc_context *ac,
|
|
unsigned long *did_some_progress)
|
|
{
|
|
struct page *page = NULL;
|
|
bool drained = false;
|
|
|
|
*did_some_progress = __perform_reclaim(gfp_mask, order, ac);
|
|
if (unlikely(!(*did_some_progress)))
|
|
return NULL;
|
|
|
|
retry:
|
|
page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac);
|
|
|
|
/*
|
|
* If an allocation failed after direct reclaim, it could be because
|
|
* pages are pinned on the per-cpu lists or in high alloc reserves.
|
|
* Shrink them and try again
|
|
*/
|
|
if (!page && !drained) {
|
|
unreserve_highatomic_pageblock(ac, false);
|
|
drain_all_pages(NULL);
|
|
drained = true;
|
|
goto retry;
|
|
}
|
|
|
|
return page;
|
|
}
|
|
|
|
static void wake_all_kswapds(unsigned int order, gfp_t gfp_mask,
|
|
const struct alloc_context *ac)
|
|
{
|
|
struct zoneref *z;
|
|
struct zone *zone;
|
|
pg_data_t *last_pgdat = NULL;
|
|
enum zone_type highest_zoneidx = ac->highest_zoneidx;
|
|
|
|
for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, highest_zoneidx,
|
|
ac->nodemask) {
|
|
if (last_pgdat != zone->zone_pgdat)
|
|
wakeup_kswapd(zone, gfp_mask, order, highest_zoneidx);
|
|
last_pgdat = zone->zone_pgdat;
|
|
}
|
|
}
|
|
|
|
static inline unsigned int
|
|
gfp_to_alloc_flags(gfp_t gfp_mask)
|
|
{
|
|
unsigned int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET;
|
|
|
|
/*
|
|
* __GFP_HIGH is assumed to be the same as ALLOC_HIGH
|
|
* and __GFP_KSWAPD_RECLAIM is assumed to be the same as ALLOC_KSWAPD
|
|
* to save two branches.
|
|
*/
|
|
BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_HIGH);
|
|
BUILD_BUG_ON(__GFP_KSWAPD_RECLAIM != (__force gfp_t) ALLOC_KSWAPD);
|
|
|
|
/*
|
|
* The caller may dip into page reserves a bit more if the caller
|
|
* cannot run direct reclaim, or if the caller has realtime scheduling
|
|
* policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
|
|
* set both ALLOC_HARDER (__GFP_ATOMIC) and ALLOC_HIGH (__GFP_HIGH).
|
|
*/
|
|
alloc_flags |= (__force int)
|
|
(gfp_mask & (__GFP_HIGH | __GFP_KSWAPD_RECLAIM));
|
|
|
|
if (gfp_mask & __GFP_ATOMIC) {
|
|
/*
|
|
* Not worth trying to allocate harder for __GFP_NOMEMALLOC even
|
|
* if it can't schedule.
|
|
*/
|
|
if (!(gfp_mask & __GFP_NOMEMALLOC))
|
|
alloc_flags |= ALLOC_HARDER;
|
|
/*
|
|
* Ignore cpuset mems for GFP_ATOMIC rather than fail, see the
|
|
* comment for __cpuset_node_allowed().
|
|
*/
|
|
alloc_flags &= ~ALLOC_CPUSET;
|
|
} else if (unlikely(rt_task(current)) && !in_interrupt())
|
|
alloc_flags |= ALLOC_HARDER;
|
|
|
|
alloc_flags = current_alloc_flags(gfp_mask, alloc_flags);
|
|
|
|
return alloc_flags;
|
|
}
|
|
|
|
static bool oom_reserves_allowed(struct task_struct *tsk)
|
|
{
|
|
if (!tsk_is_oom_victim(tsk))
|
|
return false;
|
|
|
|
/*
|
|
* !MMU doesn't have oom reaper so give access to memory reserves
|
|
* only to the thread with TIF_MEMDIE set
|
|
*/
|
|
if (!IS_ENABLED(CONFIG_MMU) && !test_thread_flag(TIF_MEMDIE))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Distinguish requests which really need access to full memory
|
|
* reserves from oom victims which can live with a portion of it
|
|
*/
|
|
static inline int __gfp_pfmemalloc_flags(gfp_t gfp_mask)
|
|
{
|
|
if (unlikely(gfp_mask & __GFP_NOMEMALLOC))
|
|
return 0;
|
|
if (gfp_mask & __GFP_MEMALLOC)
|
|
return ALLOC_NO_WATERMARKS;
|
|
if (in_serving_softirq() && (current->flags & PF_MEMALLOC))
|
|
return ALLOC_NO_WATERMARKS;
|
|
if (!in_interrupt()) {
|
|
if (current->flags & PF_MEMALLOC)
|
|
return ALLOC_NO_WATERMARKS;
|
|
else if (oom_reserves_allowed(current))
|
|
return ALLOC_OOM;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
bool gfp_pfmemalloc_allowed(gfp_t gfp_mask)
|
|
{
|
|
return !!__gfp_pfmemalloc_flags(gfp_mask);
|
|
}
|
|
|
|
/*
|
|
* Checks whether it makes sense to retry the reclaim to make a forward progress
|
|
* for the given allocation request.
|
|
*
|
|
* We give up when we either have tried MAX_RECLAIM_RETRIES in a row
|
|
* without success, or when we couldn't even meet the watermark if we
|
|
* reclaimed all remaining pages on the LRU lists.
|
|
*
|
|
* Returns true if a retry is viable or false to enter the oom path.
|
|
*/
|
|
static inline bool
|
|
should_reclaim_retry(gfp_t gfp_mask, unsigned order,
|
|
struct alloc_context *ac, int alloc_flags,
|
|
bool did_some_progress, int *no_progress_loops)
|
|
{
|
|
struct zone *zone;
|
|
struct zoneref *z;
|
|
bool ret = false;
|
|
|
|
/*
|
|
* Costly allocations might have made a progress but this doesn't mean
|
|
* their order will become available due to high fragmentation so
|
|
* always increment the no progress counter for them
|
|
*/
|
|
if (did_some_progress && order <= PAGE_ALLOC_COSTLY_ORDER)
|
|
*no_progress_loops = 0;
|
|
else
|
|
(*no_progress_loops)++;
|
|
|
|
/*
|
|
* Make sure we converge to OOM if we cannot make any progress
|
|
* several times in the row.
|
|
*/
|
|
if (*no_progress_loops > MAX_RECLAIM_RETRIES) {
|
|
/* Before OOM, exhaust highatomic_reserve */
|
|
return unreserve_highatomic_pageblock(ac, true);
|
|
}
|
|
|
|
/*
|
|
* Keep reclaiming pages while there is a chance this will lead
|
|
* somewhere. If none of the target zones can satisfy our allocation
|
|
* request even if all reclaimable pages are considered then we are
|
|
* screwed and have to go OOM.
|
|
*/
|
|
for_each_zone_zonelist_nodemask(zone, z, ac->zonelist,
|
|
ac->highest_zoneidx, ac->nodemask) {
|
|
unsigned long available;
|
|
unsigned long reclaimable;
|
|
unsigned long min_wmark = min_wmark_pages(zone);
|
|
bool wmark;
|
|
|
|
available = reclaimable = zone_reclaimable_pages(zone);
|
|
available += zone_page_state_snapshot(zone, NR_FREE_PAGES);
|
|
|
|
/*
|
|
* Would the allocation succeed if we reclaimed all
|
|
* reclaimable pages?
|
|
*/
|
|
wmark = __zone_watermark_ok(zone, order, min_wmark,
|
|
ac->highest_zoneidx, alloc_flags, available);
|
|
trace_reclaim_retry_zone(z, order, reclaimable,
|
|
available, min_wmark, *no_progress_loops, wmark);
|
|
if (wmark) {
|
|
/*
|
|
* If we didn't make any progress and have a lot of
|
|
* dirty + writeback pages then we should wait for
|
|
* an IO to complete to slow down the reclaim and
|
|
* prevent from pre mature OOM
|
|
*/
|
|
if (!did_some_progress) {
|
|
unsigned long write_pending;
|
|
|
|
write_pending = zone_page_state_snapshot(zone,
|
|
NR_ZONE_WRITE_PENDING);
|
|
|
|
if (2 * write_pending > reclaimable) {
|
|
congestion_wait(BLK_RW_ASYNC, HZ/10);
|
|
return true;
|
|
}
|
|
}
|
|
|
|
ret = true;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
out:
|
|
/*
|
|
* Memory allocation/reclaim might be called from a WQ context and the
|
|
* current implementation of the WQ concurrency control doesn't
|
|
* recognize that a particular WQ is congested if the worker thread is
|
|
* looping without ever sleeping. Therefore we have to do a short sleep
|
|
* here rather than calling cond_resched().
|
|
*/
|
|
if (current->flags & PF_WQ_WORKER)
|
|
schedule_timeout_uninterruptible(1);
|
|
else
|
|
cond_resched();
|
|
return ret;
|
|
}
|
|
|
|
static inline bool
|
|
check_retry_cpuset(int cpuset_mems_cookie, struct alloc_context *ac)
|
|
{
|
|
/*
|
|
* It's possible that cpuset's mems_allowed and the nodemask from
|
|
* mempolicy don't intersect. This should be normally dealt with by
|
|
* policy_nodemask(), but it's possible to race with cpuset update in
|
|
* such a way the check therein was true, and then it became false
|
|
* before we got our cpuset_mems_cookie here.
|
|
* This assumes that for all allocations, ac->nodemask can come only
|
|
* from MPOL_BIND mempolicy (whose documented semantics is to be ignored
|
|
* when it does not intersect with the cpuset restrictions) or the
|
|
* caller can deal with a violated nodemask.
|
|
*/
|
|
if (cpusets_enabled() && ac->nodemask &&
|
|
!cpuset_nodemask_valid_mems_allowed(ac->nodemask)) {
|
|
ac->nodemask = NULL;
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* When updating a task's mems_allowed or mempolicy nodemask, it is
|
|
* possible to race with parallel threads in such a way that our
|
|
* allocation can fail while the mask is being updated. If we are about
|
|
* to fail, check if the cpuset changed during allocation and if so,
|
|
* retry.
|
|
*/
|
|
if (read_mems_allowed_retry(cpuset_mems_cookie))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
static inline struct page *
|
|
__alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
|
|
struct alloc_context *ac)
|
|
{
|
|
bool can_direct_reclaim = gfp_mask & __GFP_DIRECT_RECLAIM;
|
|
const bool costly_order = order > PAGE_ALLOC_COSTLY_ORDER;
|
|
struct page *page = NULL;
|
|
unsigned int alloc_flags;
|
|
unsigned long did_some_progress;
|
|
enum compact_priority compact_priority;
|
|
enum compact_result compact_result;
|
|
int compaction_retries;
|
|
int no_progress_loops;
|
|
unsigned int cpuset_mems_cookie;
|
|
int reserve_flags;
|
|
|
|
/*
|
|
* We also sanity check to catch abuse of atomic reserves being used by
|
|
* callers that are not in atomic context.
|
|
*/
|
|
if (WARN_ON_ONCE((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) ==
|
|
(__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)))
|
|
gfp_mask &= ~__GFP_ATOMIC;
|
|
|
|
retry_cpuset:
|
|
compaction_retries = 0;
|
|
no_progress_loops = 0;
|
|
compact_priority = DEF_COMPACT_PRIORITY;
|
|
cpuset_mems_cookie = read_mems_allowed_begin();
|
|
|
|
/*
|
|
* The fast path uses conservative alloc_flags to succeed only until
|
|
* kswapd needs to be woken up, and to avoid the cost of setting up
|
|
* alloc_flags precisely. So we do that now.
|
|
*/
|
|
alloc_flags = gfp_to_alloc_flags(gfp_mask);
|
|
|
|
/*
|
|
* We need to recalculate the starting point for the zonelist iterator
|
|
* because we might have used different nodemask in the fast path, or
|
|
* there was a cpuset modification and we are retrying - otherwise we
|
|
* could end up iterating over non-eligible zones endlessly.
|
|
*/
|
|
ac->preferred_zoneref = first_zones_zonelist(ac->zonelist,
|
|
ac->highest_zoneidx, ac->nodemask);
|
|
if (!ac->preferred_zoneref->zone)
|
|
goto nopage;
|
|
|
|
if (alloc_flags & ALLOC_KSWAPD)
|
|
wake_all_kswapds(order, gfp_mask, ac);
|
|
|
|
/*
|
|
* The adjusted alloc_flags might result in immediate success, so try
|
|
* that first
|
|
*/
|
|
page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac);
|
|
if (page)
|
|
goto got_pg;
|
|
|
|
/*
|
|
* For costly allocations, try direct compaction first, as it's likely
|
|
* that we have enough base pages and don't need to reclaim. For non-
|
|
* movable high-order allocations, do that as well, as compaction will
|
|
* try prevent permanent fragmentation by migrating from blocks of the
|
|
* same migratetype.
|
|
* Don't try this for allocations that are allowed to ignore
|
|
* watermarks, as the ALLOC_NO_WATERMARKS attempt didn't yet happen.
|
|
*/
|
|
if (can_direct_reclaim &&
|
|
(costly_order ||
|
|
(order > 0 && ac->migratetype != MIGRATE_MOVABLE))
|
|
&& !gfp_pfmemalloc_allowed(gfp_mask)) {
|
|
page = __alloc_pages_direct_compact(gfp_mask, order,
|
|
alloc_flags, ac,
|
|
INIT_COMPACT_PRIORITY,
|
|
&compact_result);
|
|
if (page)
|
|
goto got_pg;
|
|
|
|
/*
|
|
* Checks for costly allocations with __GFP_NORETRY, which
|
|
* includes some THP page fault allocations
|
|
*/
|
|
if (costly_order && (gfp_mask & __GFP_NORETRY)) {
|
|
/*
|
|
* If allocating entire pageblock(s) and compaction
|
|
* failed because all zones are below low watermarks
|
|
* or is prohibited because it recently failed at this
|
|
* order, fail immediately unless the allocator has
|
|
* requested compaction and reclaim retry.
|
|
*
|
|
* Reclaim is
|
|
* - potentially very expensive because zones are far
|
|
* below their low watermarks or this is part of very
|
|
* bursty high order allocations,
|
|
* - not guaranteed to help because isolate_freepages()
|
|
* may not iterate over freed pages as part of its
|
|
* linear scan, and
|
|
* - unlikely to make entire pageblocks free on its
|
|
* own.
|
|
*/
|
|
if (compact_result == COMPACT_SKIPPED ||
|
|
compact_result == COMPACT_DEFERRED)
|
|
goto nopage;
|
|
|
|
/*
|
|
* Looks like reclaim/compaction is worth trying, but
|
|
* sync compaction could be very expensive, so keep
|
|
* using async compaction.
|
|
*/
|
|
compact_priority = INIT_COMPACT_PRIORITY;
|
|
}
|
|
}
|
|
|
|
retry:
|
|
/* Ensure kswapd doesn't accidentally go to sleep as long as we loop */
|
|
if (alloc_flags & ALLOC_KSWAPD)
|
|
wake_all_kswapds(order, gfp_mask, ac);
|
|
|
|
reserve_flags = __gfp_pfmemalloc_flags(gfp_mask);
|
|
if (reserve_flags)
|
|
alloc_flags = current_alloc_flags(gfp_mask, reserve_flags);
|
|
|
|
/*
|
|
* Reset the nodemask and zonelist iterators if memory policies can be
|
|
* ignored. These allocations are high priority and system rather than
|
|
* user oriented.
|
|
*/
|
|
if (!(alloc_flags & ALLOC_CPUSET) || reserve_flags) {
|
|
ac->nodemask = NULL;
|
|
ac->preferred_zoneref = first_zones_zonelist(ac->zonelist,
|
|
ac->highest_zoneidx, ac->nodemask);
|
|
}
|
|
|
|
/* Attempt with potentially adjusted zonelist and alloc_flags */
|
|
page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac);
|
|
if (page)
|
|
goto got_pg;
|
|
|
|
/* Caller is not willing to reclaim, we can't balance anything */
|
|
if (!can_direct_reclaim)
|
|
goto nopage;
|
|
|
|
/* Avoid recursion of direct reclaim */
|
|
if (current->flags & PF_MEMALLOC)
|
|
goto nopage;
|
|
|
|
/* Try direct reclaim and then allocating */
|
|
page = __alloc_pages_direct_reclaim(gfp_mask, order, alloc_flags, ac,
|
|
&did_some_progress);
|
|
if (page)
|
|
goto got_pg;
|
|
|
|
/* Try direct compaction and then allocating */
|
|
page = __alloc_pages_direct_compact(gfp_mask, order, alloc_flags, ac,
|
|
compact_priority, &compact_result);
|
|
if (page)
|
|
goto got_pg;
|
|
|
|
/* Do not loop if specifically requested */
|
|
if (gfp_mask & __GFP_NORETRY)
|
|
goto nopage;
|
|
|
|
/*
|
|
* Do not retry costly high order allocations unless they are
|
|
* __GFP_RETRY_MAYFAIL
|
|
*/
|
|
if (costly_order && !(gfp_mask & __GFP_RETRY_MAYFAIL))
|
|
goto nopage;
|
|
|
|
if (should_reclaim_retry(gfp_mask, order, ac, alloc_flags,
|
|
did_some_progress > 0, &no_progress_loops))
|
|
goto retry;
|
|
|
|
/*
|
|
* It doesn't make any sense to retry for the compaction if the order-0
|
|
* reclaim is not able to make any progress because the current
|
|
* implementation of the compaction depends on the sufficient amount
|
|
* of free memory (see __compaction_suitable)
|
|
*/
|
|
if (did_some_progress > 0 &&
|
|
should_compact_retry(ac, order, alloc_flags,
|
|
compact_result, &compact_priority,
|
|
&compaction_retries))
|
|
goto retry;
|
|
|
|
|
|
/* Deal with possible cpuset update races before we start OOM killing */
|
|
if (check_retry_cpuset(cpuset_mems_cookie, ac))
|
|
goto retry_cpuset;
|
|
|
|
/* Reclaim has failed us, start killing things */
|
|
page = __alloc_pages_may_oom(gfp_mask, order, ac, &did_some_progress);
|
|
if (page)
|
|
goto got_pg;
|
|
|
|
/* Avoid allocations with no watermarks from looping endlessly */
|
|
if (tsk_is_oom_victim(current) &&
|
|
(alloc_flags & ALLOC_OOM ||
|
|
(gfp_mask & __GFP_NOMEMALLOC)))
|
|
goto nopage;
|
|
|
|
/* Retry as long as the OOM killer is making progress */
|
|
if (did_some_progress) {
|
|
no_progress_loops = 0;
|
|
goto retry;
|
|
}
|
|
|
|
nopage:
|
|
/* Deal with possible cpuset update races before we fail */
|
|
if (check_retry_cpuset(cpuset_mems_cookie, ac))
|
|
goto retry_cpuset;
|
|
|
|
/*
|
|
* Make sure that __GFP_NOFAIL request doesn't leak out and make sure
|
|
* we always retry
|
|
*/
|
|
if (gfp_mask & __GFP_NOFAIL) {
|
|
/*
|
|
* All existing users of the __GFP_NOFAIL are blockable, so warn
|
|
* of any new users that actually require GFP_NOWAIT
|
|
*/
|
|
if (WARN_ON_ONCE(!can_direct_reclaim))
|
|
goto fail;
|
|
|
|
/*
|
|
* PF_MEMALLOC request from this context is rather bizarre
|
|
* because we cannot reclaim anything and only can loop waiting
|
|
* for somebody to do a work for us
|
|
*/
|
|
WARN_ON_ONCE(current->flags & PF_MEMALLOC);
|
|
|
|
/*
|
|
* non failing costly orders are a hard requirement which we
|
|
* are not prepared for much so let's warn about these users
|
|
* so that we can identify them and convert them to something
|
|
* else.
|
|
*/
|
|
WARN_ON_ONCE(order > PAGE_ALLOC_COSTLY_ORDER);
|
|
|
|
/*
|
|
* Help non-failing allocations by giving them access to memory
|
|
* reserves but do not use ALLOC_NO_WATERMARKS because this
|
|
* could deplete whole memory reserves which would just make
|
|
* the situation worse
|
|
*/
|
|
page = __alloc_pages_cpuset_fallback(gfp_mask, order, ALLOC_HARDER, ac);
|
|
if (page)
|
|
goto got_pg;
|
|
|
|
cond_resched();
|
|
goto retry;
|
|
}
|
|
fail:
|
|
warn_alloc(gfp_mask, ac->nodemask,
|
|
"page allocation failure: order:%u", order);
|
|
got_pg:
|
|
return page;
|
|
}
|
|
|
|
static inline bool prepare_alloc_pages(gfp_t gfp_mask, unsigned int order,
|
|
int preferred_nid, nodemask_t *nodemask,
|
|
struct alloc_context *ac, gfp_t *alloc_mask,
|
|
unsigned int *alloc_flags)
|
|
{
|
|
ac->highest_zoneidx = gfp_zone(gfp_mask);
|
|
ac->zonelist = node_zonelist(preferred_nid, gfp_mask);
|
|
ac->nodemask = nodemask;
|
|
ac->migratetype = gfp_migratetype(gfp_mask);
|
|
|
|
if (cpusets_enabled()) {
|
|
*alloc_mask |= __GFP_HARDWALL;
|
|
/*
|
|
* When we are in the interrupt context, it is irrelevant
|
|
* to the current task context. It means that any node ok.
|
|
*/
|
|
if (!in_interrupt() && !ac->nodemask)
|
|
ac->nodemask = &cpuset_current_mems_allowed;
|
|
else
|
|
*alloc_flags |= ALLOC_CPUSET;
|
|
}
|
|
|
|
fs_reclaim_acquire(gfp_mask);
|
|
fs_reclaim_release(gfp_mask);
|
|
|
|
might_sleep_if(gfp_mask & __GFP_DIRECT_RECLAIM);
|
|
|
|
if (should_fail_alloc_page(gfp_mask, order))
|
|
return false;
|
|
|
|
*alloc_flags = current_alloc_flags(gfp_mask, *alloc_flags);
|
|
|
|
/* Dirty zone balancing only done in the fast path */
|
|
ac->spread_dirty_pages = (gfp_mask & __GFP_WRITE);
|
|
|
|
/*
|
|
* The preferred zone is used for statistics but crucially it is
|
|
* also used as the starting point for the zonelist iterator. It
|
|
* may get reset for allocations that ignore memory policies.
|
|
*/
|
|
ac->preferred_zoneref = first_zones_zonelist(ac->zonelist,
|
|
ac->highest_zoneidx, ac->nodemask);
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* This is the 'heart' of the zoned buddy allocator.
|
|
*/
|
|
struct page *
|
|
__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid,
|
|
nodemask_t *nodemask)
|
|
{
|
|
struct page *page;
|
|
unsigned int alloc_flags = ALLOC_WMARK_LOW;
|
|
gfp_t alloc_mask; /* The gfp_t that was actually used for allocation */
|
|
struct alloc_context ac = { };
|
|
|
|
/*
|
|
* There are several places where we assume that the order value is sane
|
|
* so bail out early if the request is out of bound.
|
|
*/
|
|
if (unlikely(order >= MAX_ORDER)) {
|
|
WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN));
|
|
return NULL;
|
|
}
|
|
|
|
gfp_mask &= gfp_allowed_mask;
|
|
alloc_mask = gfp_mask;
|
|
if (!prepare_alloc_pages(gfp_mask, order, preferred_nid, nodemask, &ac, &alloc_mask, &alloc_flags))
|
|
return NULL;
|
|
|
|
/*
|
|
* Forbid the first pass from falling back to types that fragment
|
|
* memory until all local zones are considered.
|
|
*/
|
|
alloc_flags |= alloc_flags_nofragment(ac.preferred_zoneref->zone, gfp_mask);
|
|
|
|
/* First allocation attempt */
|
|
page = get_page_from_freelist(alloc_mask, order, alloc_flags, &ac);
|
|
if (likely(page))
|
|
goto out;
|
|
|
|
/*
|
|
* Apply scoped allocation constraints. This is mainly about GFP_NOFS
|
|
* resp. GFP_NOIO which has to be inherited for all allocation requests
|
|
* from a particular context which has been marked by
|
|
* memalloc_no{fs,io}_{save,restore}.
|
|
*/
|
|
alloc_mask = current_gfp_context(gfp_mask);
|
|
ac.spread_dirty_pages = false;
|
|
|
|
/*
|
|
* Restore the original nodemask if it was potentially replaced with
|
|
* &cpuset_current_mems_allowed to optimize the fast-path attempt.
|
|
*/
|
|
ac.nodemask = nodemask;
|
|
|
|
page = __alloc_pages_slowpath(alloc_mask, order, &ac);
|
|
|
|
out:
|
|
if (memcg_kmem_enabled() && (gfp_mask & __GFP_ACCOUNT) && page &&
|
|
unlikely(__memcg_kmem_charge_page(page, gfp_mask, order) != 0)) {
|
|
__free_pages(page, order);
|
|
page = NULL;
|
|
}
|
|
|
|
trace_mm_page_alloc(page, order, alloc_mask, ac.migratetype);
|
|
|
|
return page;
|
|
}
|
|
EXPORT_SYMBOL(__alloc_pages_nodemask);
|
|
|
|
/*
|
|
* Common helper functions. Never use with __GFP_HIGHMEM because the returned
|
|
* address cannot represent highmem pages. Use alloc_pages and then kmap if
|
|
* you need to access high mem.
|
|
*/
|
|
unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order)
|
|
{
|
|
struct page *page;
|
|
|
|
page = alloc_pages(gfp_mask & ~__GFP_HIGHMEM, order);
|
|
if (!page)
|
|
return 0;
|
|
return (unsigned long) page_address(page);
|
|
}
|
|
EXPORT_SYMBOL(__get_free_pages);
|
|
|
|
unsigned long get_zeroed_page(gfp_t gfp_mask)
|
|
{
|
|
return __get_free_pages(gfp_mask | __GFP_ZERO, 0);
|
|
}
|
|
EXPORT_SYMBOL(get_zeroed_page);
|
|
|
|
static inline void free_the_page(struct page *page, unsigned int order)
|
|
{
|
|
if (order == 0) /* Via pcp? */
|
|
free_unref_page(page);
|
|
else
|
|
__free_pages_ok(page, order, FPI_NONE);
|
|
}
|
|
|
|
/**
|
|
* __free_pages - Free pages allocated with alloc_pages().
|
|
* @page: The page pointer returned from alloc_pages().
|
|
* @order: The order of the allocation.
|
|
*
|
|
* This function can free multi-page allocations that are not compound
|
|
* pages. It does not check that the @order passed in matches that of
|
|
* the allocation, so it is easy to leak memory. Freeing more memory
|
|
* than was allocated will probably emit a warning.
|
|
*
|
|
* If the last reference to this page is speculative, it will be released
|
|
* by put_page() which only frees the first page of a non-compound
|
|
* allocation. To prevent the remaining pages from being leaked, we free
|
|
* the subsequent pages here. If you want to use the page's reference
|
|
* count to decide when to free the allocation, you should allocate a
|
|
* compound page, and use put_page() instead of __free_pages().
|
|
*
|
|
* Context: May be called in interrupt context or while holding a normal
|
|
* spinlock, but not in NMI context or while holding a raw spinlock.
|
|
*/
|
|
void __free_pages(struct page *page, unsigned int order)
|
|
{
|
|
if (put_page_testzero(page))
|
|
free_the_page(page, order);
|
|
else if (!PageHead(page))
|
|
while (order-- > 0)
|
|
free_the_page(page + (1 << order), order);
|
|
}
|
|
EXPORT_SYMBOL(__free_pages);
|
|
|
|
void free_pages(unsigned long addr, unsigned int order)
|
|
{
|
|
if (addr != 0) {
|
|
VM_BUG_ON(!virt_addr_valid((void *)addr));
|
|
__free_pages(virt_to_page((void *)addr), order);
|
|
}
|
|
}
|
|
|
|
EXPORT_SYMBOL(free_pages);
|
|
|
|
/*
|
|
* Page Fragment:
|
|
* An arbitrary-length arbitrary-offset area of memory which resides
|
|
* within a 0 or higher order page. Multiple fragments within that page
|
|
* are individually refcounted, in the page's reference counter.
|
|
*
|
|
* The page_frag functions below provide a simple allocation framework for
|
|
* page fragments. This is used by the network stack and network device
|
|
* drivers to provide a backing region of memory for use as either an
|
|
* sk_buff->head, or to be used in the "frags" portion of skb_shared_info.
|
|
*/
|
|
static struct page *__page_frag_cache_refill(struct page_frag_cache *nc,
|
|
gfp_t gfp_mask)
|
|
{
|
|
struct page *page = NULL;
|
|
gfp_t gfp = gfp_mask;
|
|
|
|
#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
|
|
gfp_mask |= __GFP_COMP | __GFP_NOWARN | __GFP_NORETRY |
|
|
__GFP_NOMEMALLOC;
|
|
page = alloc_pages_node(NUMA_NO_NODE, gfp_mask,
|
|
PAGE_FRAG_CACHE_MAX_ORDER);
|
|
nc->size = page ? PAGE_FRAG_CACHE_MAX_SIZE : PAGE_SIZE;
|
|
#endif
|
|
if (unlikely(!page))
|
|
page = alloc_pages_node(NUMA_NO_NODE, gfp, 0);
|
|
|
|
nc->va = page ? page_address(page) : NULL;
|
|
|
|
return page;
|
|
}
|
|
|
|
void __page_frag_cache_drain(struct page *page, unsigned int count)
|
|
{
|
|
VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
|
|
|
|
if (page_ref_sub_and_test(page, count))
|
|
free_the_page(page, compound_order(page));
|
|
}
|
|
EXPORT_SYMBOL(__page_frag_cache_drain);
|
|
|
|
void *page_frag_alloc_align(struct page_frag_cache *nc,
|
|
unsigned int fragsz, gfp_t gfp_mask,
|
|
unsigned int align_mask)
|
|
{
|
|
unsigned int size = PAGE_SIZE;
|
|
struct page *page;
|
|
int offset;
|
|
|
|
if (unlikely(!nc->va)) {
|
|
refill:
|
|
page = __page_frag_cache_refill(nc, gfp_mask);
|
|
if (!page)
|
|
return NULL;
|
|
|
|
#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
|
|
/* if size can vary use size else just use PAGE_SIZE */
|
|
size = nc->size;
|
|
#endif
|
|
/* Even if we own the page, we do not use atomic_set().
|
|
* This would break get_page_unless_zero() users.
|
|
*/
|
|
page_ref_add(page, PAGE_FRAG_CACHE_MAX_SIZE);
|
|
|
|
/* reset page count bias and offset to start of new frag */
|
|
nc->pfmemalloc = page_is_pfmemalloc(page);
|
|
nc->pagecnt_bias = PAGE_FRAG_CACHE_MAX_SIZE + 1;
|
|
nc->offset = size;
|
|
}
|
|
|
|
offset = nc->offset - fragsz;
|
|
if (unlikely(offset < 0)) {
|
|
page = virt_to_page(nc->va);
|
|
|
|
if (!page_ref_sub_and_test(page, nc->pagecnt_bias))
|
|
goto refill;
|
|
|
|
if (unlikely(nc->pfmemalloc)) {
|
|
free_the_page(page, compound_order(page));
|
|
goto refill;
|
|
}
|
|
|
|
#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
|
|
/* if size can vary use size else just use PAGE_SIZE */
|
|
size = nc->size;
|
|
#endif
|
|
/* OK, page count is 0, we can safely set it */
|
|
set_page_count(page, PAGE_FRAG_CACHE_MAX_SIZE + 1);
|
|
|
|
/* reset page count bias and offset to start of new frag */
|
|
nc->pagecnt_bias = PAGE_FRAG_CACHE_MAX_SIZE + 1;
|
|
offset = size - fragsz;
|
|
}
|
|
|
|
nc->pagecnt_bias--;
|
|
offset &= align_mask;
|
|
nc->offset = offset;
|
|
|
|
return nc->va + offset;
|
|
}
|
|
EXPORT_SYMBOL(page_frag_alloc_align);
|
|
|
|
/*
|
|
* Frees a page fragment allocated out of either a compound or order 0 page.
|
|
*/
|
|
void page_frag_free(void *addr)
|
|
{
|
|
struct page *page = virt_to_head_page(addr);
|
|
|
|
if (unlikely(put_page_testzero(page)))
|
|
free_the_page(page, compound_order(page));
|
|
}
|
|
EXPORT_SYMBOL(page_frag_free);
|
|
|
|
static void *make_alloc_exact(unsigned long addr, unsigned int order,
|
|
size_t size)
|
|
{
|
|
if (addr) {
|
|
unsigned long alloc_end = addr + (PAGE_SIZE << order);
|
|
unsigned long used = addr + PAGE_ALIGN(size);
|
|
|
|
split_page(virt_to_page((void *)addr), order);
|
|
while (used < alloc_end) {
|
|
free_page(used);
|
|
used += PAGE_SIZE;
|
|
}
|
|
}
|
|
return (void *)addr;
|
|
}
|
|
|
|
/**
|
|
* alloc_pages_exact - allocate an exact number physically-contiguous pages.
|
|
* @size: the number of bytes to allocate
|
|
* @gfp_mask: GFP flags for the allocation, must not contain __GFP_COMP
|
|
*
|
|
* This function is similar to alloc_pages(), except that it allocates the
|
|
* minimum number of pages to satisfy the request. alloc_pages() can only
|
|
* allocate memory in power-of-two pages.
|
|
*
|
|
* This function is also limited by MAX_ORDER.
|
|
*
|
|
* Memory allocated by this function must be released by free_pages_exact().
|
|
*
|
|
* Return: pointer to the allocated area or %NULL in case of error.
|
|
*/
|
|
void *alloc_pages_exact(size_t size, gfp_t gfp_mask)
|
|
{
|
|
unsigned int order = get_order(size);
|
|
unsigned long addr;
|
|
|
|
if (WARN_ON_ONCE(gfp_mask & __GFP_COMP))
|
|
gfp_mask &= ~__GFP_COMP;
|
|
|
|
addr = __get_free_pages(gfp_mask, order);
|
|
return make_alloc_exact(addr, order, size);
|
|
}
|
|
EXPORT_SYMBOL(alloc_pages_exact);
|
|
|
|
/**
|
|
* alloc_pages_exact_nid - allocate an exact number of physically-contiguous
|
|
* pages on a node.
|
|
* @nid: the preferred node ID where memory should be allocated
|
|
* @size: the number of bytes to allocate
|
|
* @gfp_mask: GFP flags for the allocation, must not contain __GFP_COMP
|
|
*
|
|
* Like alloc_pages_exact(), but try to allocate on node nid first before falling
|
|
* back.
|
|
*
|
|
* Return: pointer to the allocated area or %NULL in case of error.
|
|
*/
|
|
void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask)
|
|
{
|
|
unsigned int order = get_order(size);
|
|
struct page *p;
|
|
|
|
if (WARN_ON_ONCE(gfp_mask & __GFP_COMP))
|
|
gfp_mask &= ~__GFP_COMP;
|
|
|
|
p = alloc_pages_node(nid, gfp_mask, order);
|
|
if (!p)
|
|
return NULL;
|
|
return make_alloc_exact((unsigned long)page_address(p), order, size);
|
|
}
|
|
|
|
/**
|
|
* free_pages_exact - release memory allocated via alloc_pages_exact()
|
|
* @virt: the value returned by alloc_pages_exact.
|
|
* @size: size of allocation, same value as passed to alloc_pages_exact().
|
|
*
|
|
* Release the memory allocated by a previous call to alloc_pages_exact.
|
|
*/
|
|
void free_pages_exact(void *virt, size_t size)
|
|
{
|
|
unsigned long addr = (unsigned long)virt;
|
|
unsigned long end = addr + PAGE_ALIGN(size);
|
|
|
|
while (addr < end) {
|
|
free_page(addr);
|
|
addr += PAGE_SIZE;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(free_pages_exact);
|
|
|
|
/**
|
|
* nr_free_zone_pages - count number of pages beyond high watermark
|
|
* @offset: The zone index of the highest zone
|
|
*
|
|
* nr_free_zone_pages() counts the number of pages which are beyond the
|
|
* high watermark within all zones at or below a given zone index. For each
|
|
* zone, the number of pages is calculated as:
|
|
*
|
|
* nr_free_zone_pages = managed_pages - high_pages
|
|
*
|
|
* Return: number of pages beyond high watermark.
|
|
*/
|
|
static unsigned long nr_free_zone_pages(int offset)
|
|
{
|
|
struct zoneref *z;
|
|
struct zone *zone;
|
|
|
|
/* Just pick one node, since fallback list is circular */
|
|
unsigned long sum = 0;
|
|
|
|
struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL);
|
|
|
|
for_each_zone_zonelist(zone, z, zonelist, offset) {
|
|
unsigned long size = zone_managed_pages(zone);
|
|
unsigned long high = high_wmark_pages(zone);
|
|
if (size > high)
|
|
sum += size - high;
|
|
}
|
|
|
|
return sum;
|
|
}
|
|
|
|
/**
|
|
* nr_free_buffer_pages - count number of pages beyond high watermark
|
|
*
|
|
* nr_free_buffer_pages() counts the number of pages which are beyond the high
|
|
* watermark within ZONE_DMA and ZONE_NORMAL.
|
|
*
|
|
* Return: number of pages beyond high watermark within ZONE_DMA and
|
|
* ZONE_NORMAL.
|
|
*/
|
|
unsigned long nr_free_buffer_pages(void)
|
|
{
|
|
return nr_free_zone_pages(gfp_zone(GFP_USER));
|
|
}
|
|
EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
|
|
|
|
static inline void show_node(struct zone *zone)
|
|
{
|
|
if (IS_ENABLED(CONFIG_NUMA))
|
|
printk("Node %d ", zone_to_nid(zone));
|
|
}
|
|
|
|
long si_mem_available(void)
|
|
{
|
|
long available;
|
|
unsigned long pagecache;
|
|
unsigned long wmark_low = 0;
|
|
unsigned long pages[NR_LRU_LISTS];
|
|
unsigned long reclaimable;
|
|
struct zone *zone;
|
|
int lru;
|
|
|
|
for (lru = LRU_BASE; lru < NR_LRU_LISTS; lru++)
|
|
pages[lru] = global_node_page_state(NR_LRU_BASE + lru);
|
|
|
|
for_each_zone(zone)
|
|
wmark_low += low_wmark_pages(zone);
|
|
|
|
/*
|
|
* Estimate the amount of memory available for userspace allocations,
|
|
* without causing swapping.
|
|
*/
|
|
available = global_zone_page_state(NR_FREE_PAGES) - totalreserve_pages;
|
|
|
|
/*
|
|
* Not all the page cache can be freed, otherwise the system will
|
|
* start swapping. Assume at least half of the page cache, or the
|
|
* low watermark worth of cache, needs to stay.
|
|
*/
|
|
pagecache = pages[LRU_ACTIVE_FILE] + pages[LRU_INACTIVE_FILE];
|
|
pagecache -= min(pagecache / 2, wmark_low);
|
|
available += pagecache;
|
|
|
|
/*
|
|
* Part of the reclaimable slab and other kernel memory consists of
|
|
* items that are in use, and cannot be freed. Cap this estimate at the
|
|
* low watermark.
|
|
*/
|
|
reclaimable = global_node_page_state_pages(NR_SLAB_RECLAIMABLE_B) +
|
|
global_node_page_state(NR_KERNEL_MISC_RECLAIMABLE);
|
|
available += reclaimable - min(reclaimable / 2, wmark_low);
|
|
|
|
if (available < 0)
|
|
available = 0;
|
|
return available;
|
|
}
|
|
EXPORT_SYMBOL_GPL(si_mem_available);
|
|
|
|
void si_meminfo(struct sysinfo *val)
|
|
{
|
|
val->totalram = totalram_pages();
|
|
val->sharedram = global_node_page_state(NR_SHMEM);
|
|
val->freeram = global_zone_page_state(NR_FREE_PAGES);
|
|
val->bufferram = nr_blockdev_pages();
|
|
val->totalhigh = totalhigh_pages();
|
|
val->freehigh = nr_free_highpages();
|
|
val->mem_unit = PAGE_SIZE;
|
|
}
|
|
|
|
EXPORT_SYMBOL(si_meminfo);
|
|
|
|
#ifdef CONFIG_NUMA
|
|
void si_meminfo_node(struct sysinfo *val, int nid)
|
|
{
|
|
int zone_type; /* needs to be signed */
|
|
unsigned long managed_pages = 0;
|
|
unsigned long managed_highpages = 0;
|
|
unsigned long free_highpages = 0;
|
|
pg_data_t *pgdat = NODE_DATA(nid);
|
|
|
|
for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++)
|
|
managed_pages += zone_managed_pages(&pgdat->node_zones[zone_type]);
|
|
val->totalram = managed_pages;
|
|
val->sharedram = node_page_state(pgdat, NR_SHMEM);
|
|
val->freeram = sum_zone_node_page_state(nid, NR_FREE_PAGES);
|
|
#ifdef CONFIG_HIGHMEM
|
|
for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
|
|
struct zone *zone = &pgdat->node_zones[zone_type];
|
|
|
|
if (is_highmem(zone)) {
|
|
managed_highpages += zone_managed_pages(zone);
|
|
free_highpages += zone_page_state(zone, NR_FREE_PAGES);
|
|
}
|
|
}
|
|
val->totalhigh = managed_highpages;
|
|
val->freehigh = free_highpages;
|
|
#else
|
|
val->totalhigh = managed_highpages;
|
|
val->freehigh = free_highpages;
|
|
#endif
|
|
val->mem_unit = PAGE_SIZE;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Determine whether the node should be displayed or not, depending on whether
|
|
* SHOW_MEM_FILTER_NODES was passed to show_free_areas().
|
|
*/
|
|
static bool show_mem_node_skip(unsigned int flags, int nid, nodemask_t *nodemask)
|
|
{
|
|
if (!(flags & SHOW_MEM_FILTER_NODES))
|
|
return false;
|
|
|
|
/*
|
|
* no node mask - aka implicit memory numa policy. Do not bother with
|
|
* the synchronization - read_mems_allowed_begin - because we do not
|
|
* have to be precise here.
|
|
*/
|
|
if (!nodemask)
|
|
nodemask = &cpuset_current_mems_allowed;
|
|
|
|
return !node_isset(nid, *nodemask);
|
|
}
|
|
|
|
#define K(x) ((x) << (PAGE_SHIFT-10))
|
|
|
|
static void show_migration_types(unsigned char type)
|
|
{
|
|
static const char types[MIGRATE_TYPES] = {
|
|
[MIGRATE_UNMOVABLE] = 'U',
|
|
[MIGRATE_MOVABLE] = 'M',
|
|
[MIGRATE_RECLAIMABLE] = 'E',
|
|
[MIGRATE_HIGHATOMIC] = 'H',
|
|
#ifdef CONFIG_CMA
|
|
[MIGRATE_CMA] = 'C',
|
|
#endif
|
|
#ifdef CONFIG_MEMORY_ISOLATION
|
|
[MIGRATE_ISOLATE] = 'I',
|
|
#endif
|
|
};
|
|
char tmp[MIGRATE_TYPES + 1];
|
|
char *p = tmp;
|
|
int i;
|
|
|
|
for (i = 0; i < MIGRATE_TYPES; i++) {
|
|
if (type & (1 << i))
|
|
*p++ = types[i];
|
|
}
|
|
|
|
*p = '\0';
|
|
printk(KERN_CONT "(%s) ", tmp);
|
|
}
|
|
|
|
/*
|
|
* Show free area list (used inside shift_scroll-lock stuff)
|
|
* We also calculate the percentage fragmentation. We do this by counting the
|
|
* memory on each free list with the exception of the first item on the list.
|
|
*
|
|
* Bits in @filter:
|
|
* SHOW_MEM_FILTER_NODES: suppress nodes that are not allowed by current's
|
|
* cpuset.
|
|
*/
|
|
void show_free_areas(unsigned int filter, nodemask_t *nodemask)
|
|
{
|
|
unsigned long free_pcp = 0;
|
|
int cpu;
|
|
struct zone *zone;
|
|
pg_data_t *pgdat;
|
|
|
|
for_each_populated_zone(zone) {
|
|
if (show_mem_node_skip(filter, zone_to_nid(zone), nodemask))
|
|
continue;
|
|
|
|
for_each_online_cpu(cpu)
|
|
free_pcp += per_cpu_ptr(zone->pageset, cpu)->pcp.count;
|
|
}
|
|
|
|
printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
|
|
" active_file:%lu inactive_file:%lu isolated_file:%lu\n"
|
|
" unevictable:%lu dirty:%lu writeback:%lu\n"
|
|
" slab_reclaimable:%lu slab_unreclaimable:%lu\n"
|
|
" mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n"
|
|
" free:%lu free_pcp:%lu free_cma:%lu\n",
|
|
global_node_page_state(NR_ACTIVE_ANON),
|
|
global_node_page_state(NR_INACTIVE_ANON),
|
|
global_node_page_state(NR_ISOLATED_ANON),
|
|
global_node_page_state(NR_ACTIVE_FILE),
|
|
global_node_page_state(NR_INACTIVE_FILE),
|
|
global_node_page_state(NR_ISOLATED_FILE),
|
|
global_node_page_state(NR_UNEVICTABLE),
|
|
global_node_page_state(NR_FILE_DIRTY),
|
|
global_node_page_state(NR_WRITEBACK),
|
|
global_node_page_state_pages(NR_SLAB_RECLAIMABLE_B),
|
|
global_node_page_state_pages(NR_SLAB_UNRECLAIMABLE_B),
|
|
global_node_page_state(NR_FILE_MAPPED),
|
|
global_node_page_state(NR_SHMEM),
|
|
global_node_page_state(NR_PAGETABLE),
|
|
global_zone_page_state(NR_BOUNCE),
|
|
global_zone_page_state(NR_FREE_PAGES),
|
|
free_pcp,
|
|
global_zone_page_state(NR_FREE_CMA_PAGES));
|
|
|
|
for_each_online_pgdat(pgdat) {
|
|
if (show_mem_node_skip(filter, pgdat->node_id, nodemask))
|
|
continue;
|
|
|
|
printk("Node %d"
|
|
" active_anon:%lukB"
|
|
" inactive_anon:%lukB"
|
|
" active_file:%lukB"
|
|
" inactive_file:%lukB"
|
|
" unevictable:%lukB"
|
|
" isolated(anon):%lukB"
|
|
" isolated(file):%lukB"
|
|
" mapped:%lukB"
|
|
" dirty:%lukB"
|
|
" writeback:%lukB"
|
|
" shmem:%lukB"
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
" shmem_thp: %lukB"
|
|
" shmem_pmdmapped: %lukB"
|
|
" anon_thp: %lukB"
|
|
#endif
|
|
" writeback_tmp:%lukB"
|
|
" kernel_stack:%lukB"
|
|
#ifdef CONFIG_SHADOW_CALL_STACK
|
|
" shadow_call_stack:%lukB"
|
|
#endif
|
|
" pagetables:%lukB"
|
|
" all_unreclaimable? %s"
|
|
"\n",
|
|
pgdat->node_id,
|
|
K(node_page_state(pgdat, NR_ACTIVE_ANON)),
|
|
K(node_page_state(pgdat, NR_INACTIVE_ANON)),
|
|
K(node_page_state(pgdat, NR_ACTIVE_FILE)),
|
|
K(node_page_state(pgdat, NR_INACTIVE_FILE)),
|
|
K(node_page_state(pgdat, NR_UNEVICTABLE)),
|
|
K(node_page_state(pgdat, NR_ISOLATED_ANON)),
|
|
K(node_page_state(pgdat, NR_ISOLATED_FILE)),
|
|
K(node_page_state(pgdat, NR_FILE_MAPPED)),
|
|
K(node_page_state(pgdat, NR_FILE_DIRTY)),
|
|
K(node_page_state(pgdat, NR_WRITEBACK)),
|
|
K(node_page_state(pgdat, NR_SHMEM)),
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
K(node_page_state(pgdat, NR_SHMEM_THPS)),
|
|
K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED)),
|
|
K(node_page_state(pgdat, NR_ANON_THPS)),
|
|
#endif
|
|
K(node_page_state(pgdat, NR_WRITEBACK_TEMP)),
|
|
node_page_state(pgdat, NR_KERNEL_STACK_KB),
|
|
#ifdef CONFIG_SHADOW_CALL_STACK
|
|
node_page_state(pgdat, NR_KERNEL_SCS_KB),
|
|
#endif
|
|
K(node_page_state(pgdat, NR_PAGETABLE)),
|
|
pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES ?
|
|
"yes" : "no");
|
|
}
|
|
|
|
for_each_populated_zone(zone) {
|
|
int i;
|
|
|
|
if (show_mem_node_skip(filter, zone_to_nid(zone), nodemask))
|
|
continue;
|
|
|
|
free_pcp = 0;
|
|
for_each_online_cpu(cpu)
|
|
free_pcp += per_cpu_ptr(zone->pageset, cpu)->pcp.count;
|
|
|
|
show_node(zone);
|
|
printk(KERN_CONT
|
|
"%s"
|
|
" free:%lukB"
|
|
" min:%lukB"
|
|
" low:%lukB"
|
|
" high:%lukB"
|
|
" reserved_highatomic:%luKB"
|
|
" active_anon:%lukB"
|
|
" inactive_anon:%lukB"
|
|
" active_file:%lukB"
|
|
" inactive_file:%lukB"
|
|
" unevictable:%lukB"
|
|
" writepending:%lukB"
|
|
" present:%lukB"
|
|
" managed:%lukB"
|
|
" mlocked:%lukB"
|
|
" bounce:%lukB"
|
|
" free_pcp:%lukB"
|
|
" local_pcp:%ukB"
|
|
" free_cma:%lukB"
|
|
"\n",
|
|
zone->name,
|
|
K(zone_page_state(zone, NR_FREE_PAGES)),
|
|
K(min_wmark_pages(zone)),
|
|
K(low_wmark_pages(zone)),
|
|
K(high_wmark_pages(zone)),
|
|
K(zone->nr_reserved_highatomic),
|
|
K(zone_page_state(zone, NR_ZONE_ACTIVE_ANON)),
|
|
K(zone_page_state(zone, NR_ZONE_INACTIVE_ANON)),
|
|
K(zone_page_state(zone, NR_ZONE_ACTIVE_FILE)),
|
|
K(zone_page_state(zone, NR_ZONE_INACTIVE_FILE)),
|
|
K(zone_page_state(zone, NR_ZONE_UNEVICTABLE)),
|
|
K(zone_page_state(zone, NR_ZONE_WRITE_PENDING)),
|
|
K(zone->present_pages),
|
|
K(zone_managed_pages(zone)),
|
|
K(zone_page_state(zone, NR_MLOCK)),
|
|
K(zone_page_state(zone, NR_BOUNCE)),
|
|
K(free_pcp),
|
|
K(this_cpu_read(zone->pageset->pcp.count)),
|
|
K(zone_page_state(zone, NR_FREE_CMA_PAGES)));
|
|
printk("lowmem_reserve[]:");
|
|
for (i = 0; i < MAX_NR_ZONES; i++)
|
|
printk(KERN_CONT " %ld", zone->lowmem_reserve[i]);
|
|
printk(KERN_CONT "\n");
|
|
}
|
|
|
|
for_each_populated_zone(zone) {
|
|
unsigned int order;
|
|
unsigned long nr[MAX_ORDER], flags, total = 0;
|
|
unsigned char types[MAX_ORDER];
|
|
|
|
if (show_mem_node_skip(filter, zone_to_nid(zone), nodemask))
|
|
continue;
|
|
show_node(zone);
|
|
printk(KERN_CONT "%s: ", zone->name);
|
|
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
for (order = 0; order < MAX_ORDER; order++) {
|
|
struct free_area *area = &zone->free_area[order];
|
|
int type;
|
|
|
|
nr[order] = area->nr_free;
|
|
total += nr[order] << order;
|
|
|
|
types[order] = 0;
|
|
for (type = 0; type < MIGRATE_TYPES; type++) {
|
|
if (!free_area_empty(area, type))
|
|
types[order] |= 1 << type;
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
for (order = 0; order < MAX_ORDER; order++) {
|
|
printk(KERN_CONT "%lu*%lukB ",
|
|
nr[order], K(1UL) << order);
|
|
if (nr[order])
|
|
show_migration_types(types[order]);
|
|
}
|
|
printk(KERN_CONT "= %lukB\n", K(total));
|
|
}
|
|
|
|
hugetlb_show_meminfo();
|
|
|
|
printk("%ld total pagecache pages\n", global_node_page_state(NR_FILE_PAGES));
|
|
|
|
show_swap_cache_info();
|
|
}
|
|
|
|
static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref)
|
|
{
|
|
zoneref->zone = zone;
|
|
zoneref->zone_idx = zone_idx(zone);
|
|
}
|
|
|
|
/*
|
|
* Builds allocation fallback zone lists.
|
|
*
|
|
* Add all populated zones of a node to the zonelist.
|
|
*/
|
|
static int build_zonerefs_node(pg_data_t *pgdat, struct zoneref *zonerefs)
|
|
{
|
|
struct zone *zone;
|
|
enum zone_type zone_type = MAX_NR_ZONES;
|
|
int nr_zones = 0;
|
|
|
|
do {
|
|
zone_type--;
|
|
zone = pgdat->node_zones + zone_type;
|
|
if (managed_zone(zone)) {
|
|
zoneref_set_zone(zone, &zonerefs[nr_zones++]);
|
|
check_highest_zone(zone_type);
|
|
}
|
|
} while (zone_type);
|
|
|
|
return nr_zones;
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA
|
|
|
|
static int __parse_numa_zonelist_order(char *s)
|
|
{
|
|
/*
|
|
* We used to support different zonlists modes but they turned
|
|
* out to be just not useful. Let's keep the warning in place
|
|
* if somebody still use the cmd line parameter so that we do
|
|
* not fail it silently
|
|
*/
|
|
if (!(*s == 'd' || *s == 'D' || *s == 'n' || *s == 'N')) {
|
|
pr_warn("Ignoring unsupported numa_zonelist_order value: %s\n", s);
|
|
return -EINVAL;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
char numa_zonelist_order[] = "Node";
|
|
|
|
/*
|
|
* sysctl handler for numa_zonelist_order
|
|
*/
|
|
int numa_zonelist_order_handler(struct ctl_table *table, int write,
|
|
void *buffer, size_t *length, loff_t *ppos)
|
|
{
|
|
if (write)
|
|
return __parse_numa_zonelist_order(buffer);
|
|
return proc_dostring(table, write, buffer, length, ppos);
|
|
}
|
|
|
|
|
|
#define MAX_NODE_LOAD (nr_online_nodes)
|
|
static int node_load[MAX_NUMNODES];
|
|
|
|
/**
|
|
* find_next_best_node - find the next node that should appear in a given node's fallback list
|
|
* @node: node whose fallback list we're appending
|
|
* @used_node_mask: nodemask_t of already used nodes
|
|
*
|
|
* We use a number of factors to determine which is the next node that should
|
|
* appear on a given node's fallback list. The node should not have appeared
|
|
* already in @node's fallback list, and it should be the next closest node
|
|
* according to the distance array (which contains arbitrary distance values
|
|
* from each node to each node in the system), and should also prefer nodes
|
|
* with no CPUs, since presumably they'll have very little allocation pressure
|
|
* on them otherwise.
|
|
*
|
|
* Return: node id of the found node or %NUMA_NO_NODE if no node is found.
|
|
*/
|
|
static int find_next_best_node(int node, nodemask_t *used_node_mask)
|
|
{
|
|
int n, val;
|
|
int min_val = INT_MAX;
|
|
int best_node = NUMA_NO_NODE;
|
|
|
|
/* Use the local node if we haven't already */
|
|
if (!node_isset(node, *used_node_mask)) {
|
|
node_set(node, *used_node_mask);
|
|
return node;
|
|
}
|
|
|
|
for_each_node_state(n, N_MEMORY) {
|
|
|
|
/* Don't want a node to appear more than once */
|
|
if (node_isset(n, *used_node_mask))
|
|
continue;
|
|
|
|
/* Use the distance array to find the distance */
|
|
val = node_distance(node, n);
|
|
|
|
/* Penalize nodes under us ("prefer the next node") */
|
|
val += (n < node);
|
|
|
|
/* Give preference to headless and unused nodes */
|
|
if (!cpumask_empty(cpumask_of_node(n)))
|
|
val += PENALTY_FOR_NODE_WITH_CPUS;
|
|
|
|
/* Slight preference for less loaded node */
|
|
val *= (MAX_NODE_LOAD*MAX_NUMNODES);
|
|
val += node_load[n];
|
|
|
|
if (val < min_val) {
|
|
min_val = val;
|
|
best_node = n;
|
|
}
|
|
}
|
|
|
|
if (best_node >= 0)
|
|
node_set(best_node, *used_node_mask);
|
|
|
|
return best_node;
|
|
}
|
|
|
|
|
|
/*
|
|
* Build zonelists ordered by node and zones within node.
|
|
* This results in maximum locality--normal zone overflows into local
|
|
* DMA zone, if any--but risks exhausting DMA zone.
|
|
*/
|
|
static void build_zonelists_in_node_order(pg_data_t *pgdat, int *node_order,
|
|
unsigned nr_nodes)
|
|
{
|
|
struct zoneref *zonerefs;
|
|
int i;
|
|
|
|
zonerefs = pgdat->node_zonelists[ZONELIST_FALLBACK]._zonerefs;
|
|
|
|
for (i = 0; i < nr_nodes; i++) {
|
|
int nr_zones;
|
|
|
|
pg_data_t *node = NODE_DATA(node_order[i]);
|
|
|
|
nr_zones = build_zonerefs_node(node, zonerefs);
|
|
zonerefs += nr_zones;
|
|
}
|
|
zonerefs->zone = NULL;
|
|
zonerefs->zone_idx = 0;
|
|
}
|
|
|
|
/*
|
|
* Build gfp_thisnode zonelists
|
|
*/
|
|
static void build_thisnode_zonelists(pg_data_t *pgdat)
|
|
{
|
|
struct zoneref *zonerefs;
|
|
int nr_zones;
|
|
|
|
zonerefs = pgdat->node_zonelists[ZONELIST_NOFALLBACK]._zonerefs;
|
|
nr_zones = build_zonerefs_node(pgdat, zonerefs);
|
|
zonerefs += nr_zones;
|
|
zonerefs->zone = NULL;
|
|
zonerefs->zone_idx = 0;
|
|
}
|
|
|
|
/*
|
|
* Build zonelists ordered by zone and nodes within zones.
|
|
* This results in conserving DMA zone[s] until all Normal memory is
|
|
* exhausted, but results in overflowing to remote node while memory
|
|
* may still exist in local DMA zone.
|
|
*/
|
|
|
|
static void build_zonelists(pg_data_t *pgdat)
|
|
{
|
|
static int node_order[MAX_NUMNODES];
|
|
int node, load, nr_nodes = 0;
|
|
nodemask_t used_mask = NODE_MASK_NONE;
|
|
int local_node, prev_node;
|
|
|
|
/* NUMA-aware ordering of nodes */
|
|
local_node = pgdat->node_id;
|
|
load = nr_online_nodes;
|
|
prev_node = local_node;
|
|
|
|
memset(node_order, 0, sizeof(node_order));
|
|
while ((node = find_next_best_node(local_node, &used_mask)) >= 0) {
|
|
/*
|
|
* We don't want to pressure a particular node.
|
|
* So adding penalty to the first node in same
|
|
* distance group to make it round-robin.
|
|
*/
|
|
if (node_distance(local_node, node) !=
|
|
node_distance(local_node, prev_node))
|
|
node_load[node] = load;
|
|
|
|
node_order[nr_nodes++] = node;
|
|
prev_node = node;
|
|
load--;
|
|
}
|
|
|
|
build_zonelists_in_node_order(pgdat, node_order, nr_nodes);
|
|
build_thisnode_zonelists(pgdat);
|
|
}
|
|
|
|
#ifdef CONFIG_HAVE_MEMORYLESS_NODES
|
|
/*
|
|
* Return node id of node used for "local" allocations.
|
|
* I.e., first node id of first zone in arg node's generic zonelist.
|
|
* Used for initializing percpu 'numa_mem', which is used primarily
|
|
* for kernel allocations, so use GFP_KERNEL flags to locate zonelist.
|
|
*/
|
|
int local_memory_node(int node)
|
|
{
|
|
struct zoneref *z;
|
|
|
|
z = first_zones_zonelist(node_zonelist(node, GFP_KERNEL),
|
|
gfp_zone(GFP_KERNEL),
|
|
NULL);
|
|
return zone_to_nid(z->zone);
|
|
}
|
|
#endif
|
|
|
|
static void setup_min_unmapped_ratio(void);
|
|
static void setup_min_slab_ratio(void);
|
|
#else /* CONFIG_NUMA */
|
|
|
|
static void build_zonelists(pg_data_t *pgdat)
|
|
{
|
|
int node, local_node;
|
|
struct zoneref *zonerefs;
|
|
int nr_zones;
|
|
|
|
local_node = pgdat->node_id;
|
|
|
|
zonerefs = pgdat->node_zonelists[ZONELIST_FALLBACK]._zonerefs;
|
|
nr_zones = build_zonerefs_node(pgdat, zonerefs);
|
|
zonerefs += nr_zones;
|
|
|
|
/*
|
|
* Now we build the zonelist so that it contains the zones
|
|
* of all the other nodes.
|
|
* We don't want to pressure a particular node, so when
|
|
* building the zones for node N, we make sure that the
|
|
* zones coming right after the local ones are those from
|
|
* node N+1 (modulo N)
|
|
*/
|
|
for (node = local_node + 1; node < MAX_NUMNODES; node++) {
|
|
if (!node_online(node))
|
|
continue;
|
|
nr_zones = build_zonerefs_node(NODE_DATA(node), zonerefs);
|
|
zonerefs += nr_zones;
|
|
}
|
|
for (node = 0; node < local_node; node++) {
|
|
if (!node_online(node))
|
|
continue;
|
|
nr_zones = build_zonerefs_node(NODE_DATA(node), zonerefs);
|
|
zonerefs += nr_zones;
|
|
}
|
|
|
|
zonerefs->zone = NULL;
|
|
zonerefs->zone_idx = 0;
|
|
}
|
|
|
|
#endif /* CONFIG_NUMA */
|
|
|
|
/*
|
|
* Boot pageset table. One per cpu which is going to be used for all
|
|
* zones and all nodes. The parameters will be set in such a way
|
|
* that an item put on a list will immediately be handed over to
|
|
* the buddy list. This is safe since pageset manipulation is done
|
|
* with interrupts disabled.
|
|
*
|
|
* The boot_pagesets must be kept even after bootup is complete for
|
|
* unused processors and/or zones. They do play a role for bootstrapping
|
|
* hotplugged processors.
|
|
*
|
|
* zoneinfo_show() and maybe other functions do
|
|
* not check if the processor is online before following the pageset pointer.
|
|
* Other parts of the kernel may not check if the zone is available.
|
|
*/
|
|
static void pageset_init(struct per_cpu_pageset *p);
|
|
/* These effectively disable the pcplists in the boot pageset completely */
|
|
#define BOOT_PAGESET_HIGH 0
|
|
#define BOOT_PAGESET_BATCH 1
|
|
static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset);
|
|
static DEFINE_PER_CPU(struct per_cpu_nodestat, boot_nodestats);
|
|
|
|
static void __build_all_zonelists(void *data)
|
|
{
|
|
int nid;
|
|
int __maybe_unused cpu;
|
|
pg_data_t *self = data;
|
|
static DEFINE_SPINLOCK(lock);
|
|
|
|
spin_lock(&lock);
|
|
|
|
#ifdef CONFIG_NUMA
|
|
memset(node_load, 0, sizeof(node_load));
|
|
#endif
|
|
|
|
/*
|
|
* This node is hotadded and no memory is yet present. So just
|
|
* building zonelists is fine - no need to touch other nodes.
|
|
*/
|
|
if (self && !node_online(self->node_id)) {
|
|
build_zonelists(self);
|
|
} else {
|
|
for_each_online_node(nid) {
|
|
pg_data_t *pgdat = NODE_DATA(nid);
|
|
|
|
build_zonelists(pgdat);
|
|
}
|
|
|
|
#ifdef CONFIG_HAVE_MEMORYLESS_NODES
|
|
/*
|
|
* We now know the "local memory node" for each node--
|
|
* i.e., the node of the first zone in the generic zonelist.
|
|
* Set up numa_mem percpu variable for on-line cpus. During
|
|
* boot, only the boot cpu should be on-line; we'll init the
|
|
* secondary cpus' numa_mem as they come on-line. During
|
|
* node/memory hotplug, we'll fixup all on-line cpus.
|
|
*/
|
|
for_each_online_cpu(cpu)
|
|
set_cpu_numa_mem(cpu, local_memory_node(cpu_to_node(cpu)));
|
|
#endif
|
|
}
|
|
|
|
spin_unlock(&lock);
|
|
}
|
|
|
|
static noinline void __init
|
|
build_all_zonelists_init(void)
|
|
{
|
|
int cpu;
|
|
|
|
__build_all_zonelists(NULL);
|
|
|
|
/*
|
|
* Initialize the boot_pagesets that are going to be used
|
|
* for bootstrapping processors. The real pagesets for
|
|
* each zone will be allocated later when the per cpu
|
|
* allocator is available.
|
|
*
|
|
* boot_pagesets are used also for bootstrapping offline
|
|
* cpus if the system is already booted because the pagesets
|
|
* are needed to initialize allocators on a specific cpu too.
|
|
* F.e. the percpu allocator needs the page allocator which
|
|
* needs the percpu allocator in order to allocate its pagesets
|
|
* (a chicken-egg dilemma).
|
|
*/
|
|
for_each_possible_cpu(cpu)
|
|
pageset_init(&per_cpu(boot_pageset, cpu));
|
|
|
|
mminit_verify_zonelist();
|
|
cpuset_init_current_mems_allowed();
|
|
}
|
|
|
|
/*
|
|
* unless system_state == SYSTEM_BOOTING.
|
|
*
|
|
* __ref due to call of __init annotated helper build_all_zonelists_init
|
|
* [protected by SYSTEM_BOOTING].
|
|
*/
|
|
void __ref build_all_zonelists(pg_data_t *pgdat)
|
|
{
|
|
unsigned long vm_total_pages;
|
|
|
|
if (system_state == SYSTEM_BOOTING) {
|
|
build_all_zonelists_init();
|
|
} else {
|
|
__build_all_zonelists(pgdat);
|
|
/* cpuset refresh routine should be here */
|
|
}
|
|
/* Get the number of free pages beyond high watermark in all zones. */
|
|
vm_total_pages = nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
|
|
/*
|
|
* Disable grouping by mobility if the number of pages in the
|
|
* system is too low to allow the mechanism to work. It would be
|
|
* more accurate, but expensive to check per-zone. This check is
|
|
* made on memory-hotadd so a system can start with mobility
|
|
* disabled and enable it later
|
|
*/
|
|
if (vm_total_pages < (pageblock_nr_pages * MIGRATE_TYPES))
|
|
page_group_by_mobility_disabled = 1;
|
|
else
|
|
page_group_by_mobility_disabled = 0;
|
|
|
|
pr_info("Built %u zonelists, mobility grouping %s. Total pages: %ld\n",
|
|
nr_online_nodes,
|
|
page_group_by_mobility_disabled ? "off" : "on",
|
|
vm_total_pages);
|
|
#ifdef CONFIG_NUMA
|
|
pr_info("Policy zone: %s\n", zone_names[policy_zone]);
|
|
#endif
|
|
}
|
|
|
|
/* If zone is ZONE_MOVABLE but memory is mirrored, it is an overlapped init */
|
|
static bool __meminit
|
|
overlap_memmap_init(unsigned long zone, unsigned long *pfn)
|
|
{
|
|
static struct memblock_region *r;
|
|
|
|
if (mirrored_kernelcore && zone == ZONE_MOVABLE) {
|
|
if (!r || *pfn >= memblock_region_memory_end_pfn(r)) {
|
|
for_each_mem_region(r) {
|
|
if (*pfn < memblock_region_memory_end_pfn(r))
|
|
break;
|
|
}
|
|
}
|
|
if (*pfn >= memblock_region_memory_base_pfn(r) &&
|
|
memblock_is_mirror(r)) {
|
|
*pfn = memblock_region_memory_end_pfn(r);
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Initially all pages are reserved - free ones are freed
|
|
* up by memblock_free_all() once the early boot process is
|
|
* done. Non-atomic initialization, single-pass.
|
|
*
|
|
* All aligned pageblocks are initialized to the specified migratetype
|
|
* (usually MIGRATE_MOVABLE). Besides setting the migratetype, no related
|
|
* zone stats (e.g., nr_isolate_pageblock) are touched.
|
|
*/
|
|
void __meminit memmap_init_range(unsigned long size, int nid, unsigned long zone,
|
|
unsigned long start_pfn, unsigned long zone_end_pfn,
|
|
enum meminit_context context,
|
|
struct vmem_altmap *altmap, int migratetype)
|
|
{
|
|
unsigned long pfn, end_pfn = start_pfn + size;
|
|
struct page *page;
|
|
|
|
if (highest_memmap_pfn < end_pfn - 1)
|
|
highest_memmap_pfn = end_pfn - 1;
|
|
|
|
#ifdef CONFIG_ZONE_DEVICE
|
|
/*
|
|
* Honor reservation requested by the driver for this ZONE_DEVICE
|
|
* memory. We limit the total number of pages to initialize to just
|
|
* those that might contain the memory mapping. We will defer the
|
|
* ZONE_DEVICE page initialization until after we have released
|
|
* the hotplug lock.
|
|
*/
|
|
if (zone == ZONE_DEVICE) {
|
|
if (!altmap)
|
|
return;
|
|
|
|
if (start_pfn == altmap->base_pfn)
|
|
start_pfn += altmap->reserve;
|
|
end_pfn = altmap->base_pfn + vmem_altmap_offset(altmap);
|
|
}
|
|
#endif
|
|
|
|
for (pfn = start_pfn; pfn < end_pfn; ) {
|
|
/*
|
|
* There can be holes in boot-time mem_map[]s handed to this
|
|
* function. They do not exist on hotplugged memory.
|
|
*/
|
|
if (context == MEMINIT_EARLY) {
|
|
if (overlap_memmap_init(zone, &pfn))
|
|
continue;
|
|
if (defer_init(nid, pfn, zone_end_pfn))
|
|
break;
|
|
}
|
|
|
|
page = pfn_to_page(pfn);
|
|
__init_single_page(page, pfn, zone, nid);
|
|
if (context == MEMINIT_HOTPLUG)
|
|
__SetPageReserved(page);
|
|
|
|
/*
|
|
* Usually, we want to mark the pageblock MIGRATE_MOVABLE,
|
|
* such that unmovable allocations won't be scattered all
|
|
* over the place during system boot.
|
|
*/
|
|
if (IS_ALIGNED(pfn, pageblock_nr_pages)) {
|
|
set_pageblock_migratetype(page, migratetype);
|
|
cond_resched();
|
|
}
|
|
pfn++;
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_ZONE_DEVICE
|
|
void __ref memmap_init_zone_device(struct zone *zone,
|
|
unsigned long start_pfn,
|
|
unsigned long nr_pages,
|
|
struct dev_pagemap *pgmap)
|
|
{
|
|
unsigned long pfn, end_pfn = start_pfn + nr_pages;
|
|
struct pglist_data *pgdat = zone->zone_pgdat;
|
|
struct vmem_altmap *altmap = pgmap_altmap(pgmap);
|
|
unsigned long zone_idx = zone_idx(zone);
|
|
unsigned long start = jiffies;
|
|
int nid = pgdat->node_id;
|
|
|
|
if (WARN_ON_ONCE(!pgmap || zone_idx(zone) != ZONE_DEVICE))
|
|
return;
|
|
|
|
/*
|
|
* The call to memmap_init_zone should have already taken care
|
|
* of the pages reserved for the memmap, so we can just jump to
|
|
* the end of that region and start processing the device pages.
|
|
*/
|
|
if (altmap) {
|
|
start_pfn = altmap->base_pfn + vmem_altmap_offset(altmap);
|
|
nr_pages = end_pfn - start_pfn;
|
|
}
|
|
|
|
for (pfn = start_pfn; pfn < end_pfn; pfn++) {
|
|
struct page *page = pfn_to_page(pfn);
|
|
|
|
__init_single_page(page, pfn, zone_idx, nid);
|
|
|
|
/*
|
|
* Mark page reserved as it will need to wait for onlining
|
|
* phase for it to be fully associated with a zone.
|
|
*
|
|
* We can use the non-atomic __set_bit operation for setting
|
|
* the flag as we are still initializing the pages.
|
|
*/
|
|
__SetPageReserved(page);
|
|
|
|
/*
|
|
* ZONE_DEVICE pages union ->lru with a ->pgmap back pointer
|
|
* and zone_device_data. It is a bug if a ZONE_DEVICE page is
|
|
* ever freed or placed on a driver-private list.
|
|
*/
|
|
page->pgmap = pgmap;
|
|
page->zone_device_data = NULL;
|
|
|
|
/*
|
|
* Mark the block movable so that blocks are reserved for
|
|
* movable at startup. This will force kernel allocations
|
|
* to reserve their blocks rather than leaking throughout
|
|
* the address space during boot when many long-lived
|
|
* kernel allocations are made.
|
|
*
|
|
* Please note that MEMINIT_HOTPLUG path doesn't clear memmap
|
|
* because this is done early in section_activate()
|
|
*/
|
|
if (IS_ALIGNED(pfn, pageblock_nr_pages)) {
|
|
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
|
|
cond_resched();
|
|
}
|
|
}
|
|
|
|
pr_info("%s initialised %lu pages in %ums\n", __func__,
|
|
nr_pages, jiffies_to_msecs(jiffies - start));
|
|
}
|
|
|
|
#endif
|
|
static void __meminit zone_init_free_lists(struct zone *zone)
|
|
{
|
|
unsigned int order, t;
|
|
for_each_migratetype_order(order, t) {
|
|
INIT_LIST_HEAD(&zone->free_area[order].free_list[t]);
|
|
zone->free_area[order].nr_free = 0;
|
|
}
|
|
}
|
|
|
|
#if !defined(CONFIG_FLAT_NODE_MEM_MAP)
|
|
/*
|
|
* Only struct pages that correspond to ranges defined by memblock.memory
|
|
* are zeroed and initialized by going through __init_single_page() during
|
|
* memmap_init_zone().
|
|
*
|
|
* But, there could be struct pages that correspond to holes in
|
|
* memblock.memory. This can happen because of the following reasons:
|
|
* - physical memory bank size is not necessarily the exact multiple of the
|
|
* arbitrary section size
|
|
* - early reserved memory may not be listed in memblock.memory
|
|
* - memory layouts defined with memmap= kernel parameter may not align
|
|
* nicely with memmap sections
|
|
*
|
|
* Explicitly initialize those struct pages so that:
|
|
* - PG_Reserved is set
|
|
* - zone and node links point to zone and node that span the page if the
|
|
* hole is in the middle of a zone
|
|
* - zone and node links point to adjacent zone/node if the hole falls on
|
|
* the zone boundary; the pages in such holes will be prepended to the
|
|
* zone/node above the hole except for the trailing pages in the last
|
|
* section that will be appended to the zone/node below.
|
|
*/
|
|
static u64 __meminit init_unavailable_range(unsigned long spfn,
|
|
unsigned long epfn,
|
|
int zone, int node)
|
|
{
|
|
unsigned long pfn;
|
|
u64 pgcnt = 0;
|
|
|
|
for (pfn = spfn; pfn < epfn; pfn++) {
|
|
if (!pfn_valid(ALIGN_DOWN(pfn, pageblock_nr_pages))) {
|
|
pfn = ALIGN_DOWN(pfn, pageblock_nr_pages)
|
|
+ pageblock_nr_pages - 1;
|
|
continue;
|
|
}
|
|
__init_single_page(pfn_to_page(pfn), pfn, zone, node);
|
|
__SetPageReserved(pfn_to_page(pfn));
|
|
pgcnt++;
|
|
}
|
|
|
|
return pgcnt;
|
|
}
|
|
#else
|
|
static inline u64 init_unavailable_range(unsigned long spfn, unsigned long epfn,
|
|
int zone, int node)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
void __meminit __weak memmap_init_zone(struct zone *zone)
|
|
{
|
|
unsigned long zone_start_pfn = zone->zone_start_pfn;
|
|
unsigned long zone_end_pfn = zone_start_pfn + zone->spanned_pages;
|
|
int i, nid = zone_to_nid(zone), zone_id = zone_idx(zone);
|
|
static unsigned long hole_pfn;
|
|
unsigned long start_pfn, end_pfn;
|
|
u64 pgcnt = 0;
|
|
|
|
for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
|
|
start_pfn = clamp(start_pfn, zone_start_pfn, zone_end_pfn);
|
|
end_pfn = clamp(end_pfn, zone_start_pfn, zone_end_pfn);
|
|
|
|
if (end_pfn > start_pfn)
|
|
memmap_init_range(end_pfn - start_pfn, nid,
|
|
zone_id, start_pfn, zone_end_pfn,
|
|
MEMINIT_EARLY, NULL, MIGRATE_MOVABLE);
|
|
|
|
if (hole_pfn < start_pfn)
|
|
pgcnt += init_unavailable_range(hole_pfn, start_pfn,
|
|
zone_id, nid);
|
|
hole_pfn = end_pfn;
|
|
}
|
|
|
|
#ifdef CONFIG_SPARSEMEM
|
|
/*
|
|
* Initialize the hole in the range [zone_end_pfn, section_end].
|
|
* If zone boundary falls in the middle of a section, this hole
|
|
* will be re-initialized during the call to this function for the
|
|
* higher zone.
|
|
*/
|
|
end_pfn = round_up(zone_end_pfn, PAGES_PER_SECTION);
|
|
if (hole_pfn < end_pfn)
|
|
pgcnt += init_unavailable_range(hole_pfn, end_pfn,
|
|
zone_id, nid);
|
|
#endif
|
|
|
|
if (pgcnt)
|
|
pr_info(" %s zone: %llu pages in unavailable ranges\n",
|
|
zone->name, pgcnt);
|
|
}
|
|
|
|
static int zone_batchsize(struct zone *zone)
|
|
{
|
|
#ifdef CONFIG_MMU
|
|
int batch;
|
|
|
|
/*
|
|
* The per-cpu-pages pools are set to around 1000th of the
|
|
* size of the zone.
|
|
*/
|
|
batch = zone_managed_pages(zone) / 1024;
|
|
/* But no more than a meg. */
|
|
if (batch * PAGE_SIZE > 1024 * 1024)
|
|
batch = (1024 * 1024) / PAGE_SIZE;
|
|
batch /= 4; /* We effectively *= 4 below */
|
|
if (batch < 1)
|
|
batch = 1;
|
|
|
|
/*
|
|
* Clamp the batch to a 2^n - 1 value. Having a power
|
|
* of 2 value was found to be more likely to have
|
|
* suboptimal cache aliasing properties in some cases.
|
|
*
|
|
* For example if 2 tasks are alternately allocating
|
|
* batches of pages, one task can end up with a lot
|
|
* of pages of one half of the possible page colors
|
|
* and the other with pages of the other colors.
|
|
*/
|
|
batch = rounddown_pow_of_two(batch + batch/2) - 1;
|
|
|
|
return batch;
|
|
|
|
#else
|
|
/* The deferral and batching of frees should be suppressed under NOMMU
|
|
* conditions.
|
|
*
|
|
* The problem is that NOMMU needs to be able to allocate large chunks
|
|
* of contiguous memory as there's no hardware page translation to
|
|
* assemble apparent contiguous memory from discontiguous pages.
|
|
*
|
|
* Queueing large contiguous runs of pages for batching, however,
|
|
* causes the pages to actually be freed in smaller chunks. As there
|
|
* can be a significant delay between the individual batches being
|
|
* recycled, this leads to the once large chunks of space being
|
|
* fragmented and becoming unavailable for high-order allocations.
|
|
*/
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* pcp->high and pcp->batch values are related and generally batch is lower
|
|
* than high. They are also related to pcp->count such that count is lower
|
|
* than high, and as soon as it reaches high, the pcplist is flushed.
|
|
*
|
|
* However, guaranteeing these relations at all times would require e.g. write
|
|
* barriers here but also careful usage of read barriers at the read side, and
|
|
* thus be prone to error and bad for performance. Thus the update only prevents
|
|
* store tearing. Any new users of pcp->batch and pcp->high should ensure they
|
|
* can cope with those fields changing asynchronously, and fully trust only the
|
|
* pcp->count field on the local CPU with interrupts disabled.
|
|
*
|
|
* mutex_is_locked(&pcp_batch_high_lock) required when calling this function
|
|
* outside of boot time (or some other assurance that no concurrent updaters
|
|
* exist).
|
|
*/
|
|
static void pageset_update(struct per_cpu_pages *pcp, unsigned long high,
|
|
unsigned long batch)
|
|
{
|
|
WRITE_ONCE(pcp->batch, batch);
|
|
WRITE_ONCE(pcp->high, high);
|
|
}
|
|
|
|
static void pageset_init(struct per_cpu_pageset *p)
|
|
{
|
|
struct per_cpu_pages *pcp;
|
|
int migratetype;
|
|
|
|
memset(p, 0, sizeof(*p));
|
|
|
|
pcp = &p->pcp;
|
|
for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++)
|
|
INIT_LIST_HEAD(&pcp->lists[migratetype]);
|
|
|
|
/*
|
|
* Set batch and high values safe for a boot pageset. A true percpu
|
|
* pageset's initialization will update them subsequently. Here we don't
|
|
* need to be as careful as pageset_update() as nobody can access the
|
|
* pageset yet.
|
|
*/
|
|
pcp->high = BOOT_PAGESET_HIGH;
|
|
pcp->batch = BOOT_PAGESET_BATCH;
|
|
}
|
|
|
|
static void __zone_set_pageset_high_and_batch(struct zone *zone, unsigned long high,
|
|
unsigned long batch)
|
|
{
|
|
struct per_cpu_pageset *p;
|
|
int cpu;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
p = per_cpu_ptr(zone->pageset, cpu);
|
|
pageset_update(&p->pcp, high, batch);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Calculate and set new high and batch values for all per-cpu pagesets of a
|
|
* zone, based on the zone's size and the percpu_pagelist_fraction sysctl.
|
|
*/
|
|
static void zone_set_pageset_high_and_batch(struct zone *zone)
|
|
{
|
|
unsigned long new_high, new_batch;
|
|
|
|
if (percpu_pagelist_fraction) {
|
|
new_high = zone_managed_pages(zone) / percpu_pagelist_fraction;
|
|
new_batch = max(1UL, new_high / 4);
|
|
if ((new_high / 4) > (PAGE_SHIFT * 8))
|
|
new_batch = PAGE_SHIFT * 8;
|
|
} else {
|
|
new_batch = zone_batchsize(zone);
|
|
new_high = 6 * new_batch;
|
|
new_batch = max(1UL, 1 * new_batch);
|
|
}
|
|
|
|
if (zone->pageset_high == new_high &&
|
|
zone->pageset_batch == new_batch)
|
|
return;
|
|
|
|
zone->pageset_high = new_high;
|
|
zone->pageset_batch = new_batch;
|
|
|
|
__zone_set_pageset_high_and_batch(zone, new_high, new_batch);
|
|
}
|
|
|
|
void __meminit setup_zone_pageset(struct zone *zone)
|
|
{
|
|
struct per_cpu_pageset *p;
|
|
int cpu;
|
|
|
|
zone->pageset = alloc_percpu(struct per_cpu_pageset);
|
|
for_each_possible_cpu(cpu) {
|
|
p = per_cpu_ptr(zone->pageset, cpu);
|
|
pageset_init(p);
|
|
}
|
|
|
|
zone_set_pageset_high_and_batch(zone);
|
|
}
|
|
|
|
/*
|
|
* Allocate per cpu pagesets and initialize them.
|
|
* Before this call only boot pagesets were available.
|
|
*/
|
|
void __init setup_per_cpu_pageset(void)
|
|
{
|
|
struct pglist_data *pgdat;
|
|
struct zone *zone;
|
|
int __maybe_unused cpu;
|
|
|
|
for_each_populated_zone(zone)
|
|
setup_zone_pageset(zone);
|
|
|
|
#ifdef CONFIG_NUMA
|
|
/*
|
|
* Unpopulated zones continue using the boot pagesets.
|
|
* The numa stats for these pagesets need to be reset.
|
|
* Otherwise, they will end up skewing the stats of
|
|
* the nodes these zones are associated with.
|
|
*/
|
|
for_each_possible_cpu(cpu) {
|
|
struct per_cpu_pageset *pcp = &per_cpu(boot_pageset, cpu);
|
|
memset(pcp->vm_numa_stat_diff, 0,
|
|
sizeof(pcp->vm_numa_stat_diff));
|
|
}
|
|
#endif
|
|
|
|
for_each_online_pgdat(pgdat)
|
|
pgdat->per_cpu_nodestats =
|
|
alloc_percpu(struct per_cpu_nodestat);
|
|
}
|
|
|
|
static __meminit void zone_pcp_init(struct zone *zone)
|
|
{
|
|
/*
|
|
* per cpu subsystem is not up at this point. The following code
|
|
* relies on the ability of the linker to provide the
|
|
* offset of a (static) per cpu variable into the per cpu area.
|
|
*/
|
|
zone->pageset = &boot_pageset;
|
|
zone->pageset_high = BOOT_PAGESET_HIGH;
|
|
zone->pageset_batch = BOOT_PAGESET_BATCH;
|
|
|
|
if (populated_zone(zone))
|
|
printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%u\n",
|
|
zone->name, zone->present_pages,
|
|
zone_batchsize(zone));
|
|
}
|
|
|
|
void __meminit init_currently_empty_zone(struct zone *zone,
|
|
unsigned long zone_start_pfn,
|
|
unsigned long size)
|
|
{
|
|
struct pglist_data *pgdat = zone->zone_pgdat;
|
|
int zone_idx = zone_idx(zone) + 1;
|
|
|
|
if (zone_idx > pgdat->nr_zones)
|
|
pgdat->nr_zones = zone_idx;
|
|
|
|
zone->zone_start_pfn = zone_start_pfn;
|
|
|
|
mminit_dprintk(MMINIT_TRACE, "memmap_init",
|
|
"Initialising map node %d zone %lu pfns %lu -> %lu\n",
|
|
pgdat->node_id,
|
|
(unsigned long)zone_idx(zone),
|
|
zone_start_pfn, (zone_start_pfn + size));
|
|
|
|
zone_init_free_lists(zone);
|
|
zone->initialized = 1;
|
|
}
|
|
|
|
/**
|
|
* get_pfn_range_for_nid - Return the start and end page frames for a node
|
|
* @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
|
|
* @start_pfn: Passed by reference. On return, it will have the node start_pfn.
|
|
* @end_pfn: Passed by reference. On return, it will have the node end_pfn.
|
|
*
|
|
* It returns the start and end page frame of a node based on information
|
|
* provided by memblock_set_node(). If called for a node
|
|
* with no available memory, a warning is printed and the start and end
|
|
* PFNs will be 0.
|
|
*/
|
|
void __init get_pfn_range_for_nid(unsigned int nid,
|
|
unsigned long *start_pfn, unsigned long *end_pfn)
|
|
{
|
|
unsigned long this_start_pfn, this_end_pfn;
|
|
int i;
|
|
|
|
*start_pfn = -1UL;
|
|
*end_pfn = 0;
|
|
|
|
for_each_mem_pfn_range(i, nid, &this_start_pfn, &this_end_pfn, NULL) {
|
|
*start_pfn = min(*start_pfn, this_start_pfn);
|
|
*end_pfn = max(*end_pfn, this_end_pfn);
|
|
}
|
|
|
|
if (*start_pfn == -1UL)
|
|
*start_pfn = 0;
|
|
}
|
|
|
|
/*
|
|
* This finds a zone that can be used for ZONE_MOVABLE pages. The
|
|
* assumption is made that zones within a node are ordered in monotonic
|
|
* increasing memory addresses so that the "highest" populated zone is used
|
|
*/
|
|
static void __init find_usable_zone_for_movable(void)
|
|
{
|
|
int zone_index;
|
|
for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) {
|
|
if (zone_index == ZONE_MOVABLE)
|
|
continue;
|
|
|
|
if (arch_zone_highest_possible_pfn[zone_index] >
|
|
arch_zone_lowest_possible_pfn[zone_index])
|
|
break;
|
|
}
|
|
|
|
VM_BUG_ON(zone_index == -1);
|
|
movable_zone = zone_index;
|
|
}
|
|
|
|
/*
|
|
* The zone ranges provided by the architecture do not include ZONE_MOVABLE
|
|
* because it is sized independent of architecture. Unlike the other zones,
|
|
* the starting point for ZONE_MOVABLE is not fixed. It may be different
|
|
* in each node depending on the size of each node and how evenly kernelcore
|
|
* is distributed. This helper function adjusts the zone ranges
|
|
* provided by the architecture for a given node by using the end of the
|
|
* highest usable zone for ZONE_MOVABLE. This preserves the assumption that
|
|
* zones within a node are in order of monotonic increases memory addresses
|
|
*/
|
|
static void __init adjust_zone_range_for_zone_movable(int nid,
|
|
unsigned long zone_type,
|
|
unsigned long node_start_pfn,
|
|
unsigned long node_end_pfn,
|
|
unsigned long *zone_start_pfn,
|
|
unsigned long *zone_end_pfn)
|
|
{
|
|
/* Only adjust if ZONE_MOVABLE is on this node */
|
|
if (zone_movable_pfn[nid]) {
|
|
/* Size ZONE_MOVABLE */
|
|
if (zone_type == ZONE_MOVABLE) {
|
|
*zone_start_pfn = zone_movable_pfn[nid];
|
|
*zone_end_pfn = min(node_end_pfn,
|
|
arch_zone_highest_possible_pfn[movable_zone]);
|
|
|
|
/* Adjust for ZONE_MOVABLE starting within this range */
|
|
} else if (!mirrored_kernelcore &&
|
|
*zone_start_pfn < zone_movable_pfn[nid] &&
|
|
*zone_end_pfn > zone_movable_pfn[nid]) {
|
|
*zone_end_pfn = zone_movable_pfn[nid];
|
|
|
|
/* Check if this whole range is within ZONE_MOVABLE */
|
|
} else if (*zone_start_pfn >= zone_movable_pfn[nid])
|
|
*zone_start_pfn = *zone_end_pfn;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Return the number of pages a zone spans in a node, including holes
|
|
* present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
|
|
*/
|
|
static unsigned long __init zone_spanned_pages_in_node(int nid,
|
|
unsigned long zone_type,
|
|
unsigned long node_start_pfn,
|
|
unsigned long node_end_pfn,
|
|
unsigned long *zone_start_pfn,
|
|
unsigned long *zone_end_pfn)
|
|
{
|
|
unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type];
|
|
unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type];
|
|
/* When hotadd a new node from cpu_up(), the node should be empty */
|
|
if (!node_start_pfn && !node_end_pfn)
|
|
return 0;
|
|
|
|
/* Get the start and end of the zone */
|
|
*zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high);
|
|
*zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high);
|
|
adjust_zone_range_for_zone_movable(nid, zone_type,
|
|
node_start_pfn, node_end_pfn,
|
|
zone_start_pfn, zone_end_pfn);
|
|
|
|
/* Check that this node has pages within the zone's required range */
|
|
if (*zone_end_pfn < node_start_pfn || *zone_start_pfn > node_end_pfn)
|
|
return 0;
|
|
|
|
/* Move the zone boundaries inside the node if necessary */
|
|
*zone_end_pfn = min(*zone_end_pfn, node_end_pfn);
|
|
*zone_start_pfn = max(*zone_start_pfn, node_start_pfn);
|
|
|
|
/* Return the spanned pages */
|
|
return *zone_end_pfn - *zone_start_pfn;
|
|
}
|
|
|
|
/*
|
|
* Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
|
|
* then all holes in the requested range will be accounted for.
|
|
*/
|
|
unsigned long __init __absent_pages_in_range(int nid,
|
|
unsigned long range_start_pfn,
|
|
unsigned long range_end_pfn)
|
|
{
|
|
unsigned long nr_absent = range_end_pfn - range_start_pfn;
|
|
unsigned long start_pfn, end_pfn;
|
|
int i;
|
|
|
|
for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
|
|
start_pfn = clamp(start_pfn, range_start_pfn, range_end_pfn);
|
|
end_pfn = clamp(end_pfn, range_start_pfn, range_end_pfn);
|
|
nr_absent -= end_pfn - start_pfn;
|
|
}
|
|
return nr_absent;
|
|
}
|
|
|
|
/**
|
|
* absent_pages_in_range - Return number of page frames in holes within a range
|
|
* @start_pfn: The start PFN to start searching for holes
|
|
* @end_pfn: The end PFN to stop searching for holes
|
|
*
|
|
* Return: the number of pages frames in memory holes within a range.
|
|
*/
|
|
unsigned long __init absent_pages_in_range(unsigned long start_pfn,
|
|
unsigned long end_pfn)
|
|
{
|
|
return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn);
|
|
}
|
|
|
|
/* Return the number of page frames in holes in a zone on a node */
|
|
static unsigned long __init zone_absent_pages_in_node(int nid,
|
|
unsigned long zone_type,
|
|
unsigned long node_start_pfn,
|
|
unsigned long node_end_pfn)
|
|
{
|
|
unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type];
|
|
unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type];
|
|
unsigned long zone_start_pfn, zone_end_pfn;
|
|
unsigned long nr_absent;
|
|
|
|
/* When hotadd a new node from cpu_up(), the node should be empty */
|
|
if (!node_start_pfn && !node_end_pfn)
|
|
return 0;
|
|
|
|
zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high);
|
|
zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high);
|
|
|
|
adjust_zone_range_for_zone_movable(nid, zone_type,
|
|
node_start_pfn, node_end_pfn,
|
|
&zone_start_pfn, &zone_end_pfn);
|
|
nr_absent = __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
|
|
|
|
/*
|
|
* ZONE_MOVABLE handling.
|
|
* Treat pages to be ZONE_MOVABLE in ZONE_NORMAL as absent pages
|
|
* and vice versa.
|
|
*/
|
|
if (mirrored_kernelcore && zone_movable_pfn[nid]) {
|
|
unsigned long start_pfn, end_pfn;
|
|
struct memblock_region *r;
|
|
|
|
for_each_mem_region(r) {
|
|
start_pfn = clamp(memblock_region_memory_base_pfn(r),
|
|
zone_start_pfn, zone_end_pfn);
|
|
end_pfn = clamp(memblock_region_memory_end_pfn(r),
|
|
zone_start_pfn, zone_end_pfn);
|
|
|
|
if (zone_type == ZONE_MOVABLE &&
|
|
memblock_is_mirror(r))
|
|
nr_absent += end_pfn - start_pfn;
|
|
|
|
if (zone_type == ZONE_NORMAL &&
|
|
!memblock_is_mirror(r))
|
|
nr_absent += end_pfn - start_pfn;
|
|
}
|
|
}
|
|
|
|
return nr_absent;
|
|
}
|
|
|
|
static void __init calculate_node_totalpages(struct pglist_data *pgdat,
|
|
unsigned long node_start_pfn,
|
|
unsigned long node_end_pfn)
|
|
{
|
|
unsigned long realtotalpages = 0, totalpages = 0;
|
|
enum zone_type i;
|
|
|
|
for (i = 0; i < MAX_NR_ZONES; i++) {
|
|
struct zone *zone = pgdat->node_zones + i;
|
|
unsigned long zone_start_pfn, zone_end_pfn;
|
|
unsigned long spanned, absent;
|
|
unsigned long size, real_size;
|
|
|
|
spanned = zone_spanned_pages_in_node(pgdat->node_id, i,
|
|
node_start_pfn,
|
|
node_end_pfn,
|
|
&zone_start_pfn,
|
|
&zone_end_pfn);
|
|
absent = zone_absent_pages_in_node(pgdat->node_id, i,
|
|
node_start_pfn,
|
|
node_end_pfn);
|
|
|
|
size = spanned;
|
|
real_size = size - absent;
|
|
|
|
if (size)
|
|
zone->zone_start_pfn = zone_start_pfn;
|
|
else
|
|
zone->zone_start_pfn = 0;
|
|
zone->spanned_pages = size;
|
|
zone->present_pages = real_size;
|
|
|
|
totalpages += size;
|
|
realtotalpages += real_size;
|
|
}
|
|
|
|
pgdat->node_spanned_pages = totalpages;
|
|
pgdat->node_present_pages = realtotalpages;
|
|
printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id,
|
|
realtotalpages);
|
|
}
|
|
|
|
#ifndef CONFIG_SPARSEMEM
|
|
/*
|
|
* Calculate the size of the zone->blockflags rounded to an unsigned long
|
|
* Start by making sure zonesize is a multiple of pageblock_order by rounding
|
|
* up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
|
|
* round what is now in bits to nearest long in bits, then return it in
|
|
* bytes.
|
|
*/
|
|
static unsigned long __init usemap_size(unsigned long zone_start_pfn, unsigned long zonesize)
|
|
{
|
|
unsigned long usemapsize;
|
|
|
|
zonesize += zone_start_pfn & (pageblock_nr_pages-1);
|
|
usemapsize = roundup(zonesize, pageblock_nr_pages);
|
|
usemapsize = usemapsize >> pageblock_order;
|
|
usemapsize *= NR_PAGEBLOCK_BITS;
|
|
usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long));
|
|
|
|
return usemapsize / 8;
|
|
}
|
|
|
|
static void __ref setup_usemap(struct zone *zone)
|
|
{
|
|
unsigned long usemapsize = usemap_size(zone->zone_start_pfn,
|
|
zone->spanned_pages);
|
|
zone->pageblock_flags = NULL;
|
|
if (usemapsize) {
|
|
zone->pageblock_flags =
|
|
memblock_alloc_node(usemapsize, SMP_CACHE_BYTES,
|
|
zone_to_nid(zone));
|
|
if (!zone->pageblock_flags)
|
|
panic("Failed to allocate %ld bytes for zone %s pageblock flags on node %d\n",
|
|
usemapsize, zone->name, zone_to_nid(zone));
|
|
}
|
|
}
|
|
#else
|
|
static inline void setup_usemap(struct zone *zone) {}
|
|
#endif /* CONFIG_SPARSEMEM */
|
|
|
|
#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
|
|
|
|
/* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
|
|
void __init set_pageblock_order(void)
|
|
{
|
|
unsigned int order;
|
|
|
|
/* Check that pageblock_nr_pages has not already been setup */
|
|
if (pageblock_order)
|
|
return;
|
|
|
|
if (HPAGE_SHIFT > PAGE_SHIFT)
|
|
order = HUGETLB_PAGE_ORDER;
|
|
else
|
|
order = MAX_ORDER - 1;
|
|
|
|
/*
|
|
* Assume the largest contiguous order of interest is a huge page.
|
|
* This value may be variable depending on boot parameters on IA64 and
|
|
* powerpc.
|
|
*/
|
|
pageblock_order = order;
|
|
}
|
|
#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
|
|
|
|
/*
|
|
* When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
|
|
* is unused as pageblock_order is set at compile-time. See
|
|
* include/linux/pageblock-flags.h for the values of pageblock_order based on
|
|
* the kernel config
|
|
*/
|
|
void __init set_pageblock_order(void)
|
|
{
|
|
}
|
|
|
|
#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
|
|
|
|
static unsigned long __init calc_memmap_size(unsigned long spanned_pages,
|
|
unsigned long present_pages)
|
|
{
|
|
unsigned long pages = spanned_pages;
|
|
|
|
/*
|
|
* Provide a more accurate estimation if there are holes within
|
|
* the zone and SPARSEMEM is in use. If there are holes within the
|
|
* zone, each populated memory region may cost us one or two extra
|
|
* memmap pages due to alignment because memmap pages for each
|
|
* populated regions may not be naturally aligned on page boundary.
|
|
* So the (present_pages >> 4) heuristic is a tradeoff for that.
|
|
*/
|
|
if (spanned_pages > present_pages + (present_pages >> 4) &&
|
|
IS_ENABLED(CONFIG_SPARSEMEM))
|
|
pages = present_pages;
|
|
|
|
return PAGE_ALIGN(pages * sizeof(struct page)) >> PAGE_SHIFT;
|
|
}
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
static void pgdat_init_split_queue(struct pglist_data *pgdat)
|
|
{
|
|
struct deferred_split *ds_queue = &pgdat->deferred_split_queue;
|
|
|
|
spin_lock_init(&ds_queue->split_queue_lock);
|
|
INIT_LIST_HEAD(&ds_queue->split_queue);
|
|
ds_queue->split_queue_len = 0;
|
|
}
|
|
#else
|
|
static void pgdat_init_split_queue(struct pglist_data *pgdat) {}
|
|
#endif
|
|
|
|
#ifdef CONFIG_COMPACTION
|
|
static void pgdat_init_kcompactd(struct pglist_data *pgdat)
|
|
{
|
|
init_waitqueue_head(&pgdat->kcompactd_wait);
|
|
}
|
|
#else
|
|
static void pgdat_init_kcompactd(struct pglist_data *pgdat) {}
|
|
#endif
|
|
|
|
static void __meminit pgdat_init_internals(struct pglist_data *pgdat)
|
|
{
|
|
pgdat_resize_init(pgdat);
|
|
|
|
pgdat_init_split_queue(pgdat);
|
|
pgdat_init_kcompactd(pgdat);
|
|
|
|
init_waitqueue_head(&pgdat->kswapd_wait);
|
|
init_waitqueue_head(&pgdat->pfmemalloc_wait);
|
|
|
|
pgdat_page_ext_init(pgdat);
|
|
lruvec_init(&pgdat->__lruvec);
|
|
}
|
|
|
|
static void __meminit zone_init_internals(struct zone *zone, enum zone_type idx, int nid,
|
|
unsigned long remaining_pages)
|
|
{
|
|
atomic_long_set(&zone->managed_pages, remaining_pages);
|
|
zone_set_nid(zone, nid);
|
|
zone->name = zone_names[idx];
|
|
zone->zone_pgdat = NODE_DATA(nid);
|
|
spin_lock_init(&zone->lock);
|
|
zone_seqlock_init(zone);
|
|
zone_pcp_init(zone);
|
|
}
|
|
|
|
/*
|
|
* Set up the zone data structures
|
|
* - init pgdat internals
|
|
* - init all zones belonging to this node
|
|
*
|
|
* NOTE: this function is only called during memory hotplug
|
|
*/
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
void __ref free_area_init_core_hotplug(int nid)
|
|
{
|
|
enum zone_type z;
|
|
pg_data_t *pgdat = NODE_DATA(nid);
|
|
|
|
pgdat_init_internals(pgdat);
|
|
for (z = 0; z < MAX_NR_ZONES; z++)
|
|
zone_init_internals(&pgdat->node_zones[z], z, nid, 0);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Set up the zone data structures:
|
|
* - mark all pages reserved
|
|
* - mark all memory queues empty
|
|
* - clear the memory bitmaps
|
|
*
|
|
* NOTE: pgdat should get zeroed by caller.
|
|
* NOTE: this function is only called during early init.
|
|
*/
|
|
static void __init free_area_init_core(struct pglist_data *pgdat)
|
|
{
|
|
enum zone_type j;
|
|
int nid = pgdat->node_id;
|
|
|
|
pgdat_init_internals(pgdat);
|
|
pgdat->per_cpu_nodestats = &boot_nodestats;
|
|
|
|
for (j = 0; j < MAX_NR_ZONES; j++) {
|
|
struct zone *zone = pgdat->node_zones + j;
|
|
unsigned long size, freesize, memmap_pages;
|
|
|
|
size = zone->spanned_pages;
|
|
freesize = zone->present_pages;
|
|
|
|
/*
|
|
* Adjust freesize so that it accounts for how much memory
|
|
* is used by this zone for memmap. This affects the watermark
|
|
* and per-cpu initialisations
|
|
*/
|
|
memmap_pages = calc_memmap_size(size, freesize);
|
|
if (!is_highmem_idx(j)) {
|
|
if (freesize >= memmap_pages) {
|
|
freesize -= memmap_pages;
|
|
if (memmap_pages)
|
|
printk(KERN_DEBUG
|
|
" %s zone: %lu pages used for memmap\n",
|
|
zone_names[j], memmap_pages);
|
|
} else
|
|
pr_warn(" %s zone: %lu pages exceeds freesize %lu\n",
|
|
zone_names[j], memmap_pages, freesize);
|
|
}
|
|
|
|
/* Account for reserved pages */
|
|
if (j == 0 && freesize > dma_reserve) {
|
|
freesize -= dma_reserve;
|
|
printk(KERN_DEBUG " %s zone: %lu pages reserved\n",
|
|
zone_names[0], dma_reserve);
|
|
}
|
|
|
|
if (!is_highmem_idx(j))
|
|
nr_kernel_pages += freesize;
|
|
/* Charge for highmem memmap if there are enough kernel pages */
|
|
else if (nr_kernel_pages > memmap_pages * 2)
|
|
nr_kernel_pages -= memmap_pages;
|
|
nr_all_pages += freesize;
|
|
|
|
/*
|
|
* Set an approximate value for lowmem here, it will be adjusted
|
|
* when the bootmem allocator frees pages into the buddy system.
|
|
* And all highmem pages will be managed by the buddy system.
|
|
*/
|
|
zone_init_internals(zone, j, nid, freesize);
|
|
|
|
if (!size)
|
|
continue;
|
|
|
|
set_pageblock_order();
|
|
setup_usemap(zone);
|
|
init_currently_empty_zone(zone, zone->zone_start_pfn, size);
|
|
memmap_init_zone(zone);
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_FLAT_NODE_MEM_MAP
|
|
static void __ref alloc_node_mem_map(struct pglist_data *pgdat)
|
|
{
|
|
unsigned long __maybe_unused start = 0;
|
|
unsigned long __maybe_unused offset = 0;
|
|
|
|
/* Skip empty nodes */
|
|
if (!pgdat->node_spanned_pages)
|
|
return;
|
|
|
|
start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
|
|
offset = pgdat->node_start_pfn - start;
|
|
/* ia64 gets its own node_mem_map, before this, without bootmem */
|
|
if (!pgdat->node_mem_map) {
|
|
unsigned long size, end;
|
|
struct page *map;
|
|
|
|
/*
|
|
* The zone's endpoints aren't required to be MAX_ORDER
|
|
* aligned but the node_mem_map endpoints must be in order
|
|
* for the buddy allocator to function correctly.
|
|
*/
|
|
end = pgdat_end_pfn(pgdat);
|
|
end = ALIGN(end, MAX_ORDER_NR_PAGES);
|
|
size = (end - start) * sizeof(struct page);
|
|
map = memblock_alloc_node(size, SMP_CACHE_BYTES,
|
|
pgdat->node_id);
|
|
if (!map)
|
|
panic("Failed to allocate %ld bytes for node %d memory map\n",
|
|
size, pgdat->node_id);
|
|
pgdat->node_mem_map = map + offset;
|
|
}
|
|
pr_debug("%s: node %d, pgdat %08lx, node_mem_map %08lx\n",
|
|
__func__, pgdat->node_id, (unsigned long)pgdat,
|
|
(unsigned long)pgdat->node_mem_map);
|
|
#ifndef CONFIG_NEED_MULTIPLE_NODES
|
|
/*
|
|
* With no DISCONTIG, the global mem_map is just set as node 0's
|
|
*/
|
|
if (pgdat == NODE_DATA(0)) {
|
|
mem_map = NODE_DATA(0)->node_mem_map;
|
|
if (page_to_pfn(mem_map) != pgdat->node_start_pfn)
|
|
mem_map -= offset;
|
|
}
|
|
#endif
|
|
}
|
|
#else
|
|
static void __ref alloc_node_mem_map(struct pglist_data *pgdat) { }
|
|
#endif /* CONFIG_FLAT_NODE_MEM_MAP */
|
|
|
|
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
|
|
static inline void pgdat_set_deferred_range(pg_data_t *pgdat)
|
|
{
|
|
pgdat->first_deferred_pfn = ULONG_MAX;
|
|
}
|
|
#else
|
|
static inline void pgdat_set_deferred_range(pg_data_t *pgdat) {}
|
|
#endif
|
|
|
|
static void __init free_area_init_node(int nid)
|
|
{
|
|
pg_data_t *pgdat = NODE_DATA(nid);
|
|
unsigned long start_pfn = 0;
|
|
unsigned long end_pfn = 0;
|
|
|
|
/* pg_data_t should be reset to zero when it's allocated */
|
|
WARN_ON(pgdat->nr_zones || pgdat->kswapd_highest_zoneidx);
|
|
|
|
get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
|
|
|
|
pgdat->node_id = nid;
|
|
pgdat->node_start_pfn = start_pfn;
|
|
pgdat->per_cpu_nodestats = NULL;
|
|
|
|
pr_info("Initmem setup node %d [mem %#018Lx-%#018Lx]\n", nid,
|
|
(u64)start_pfn << PAGE_SHIFT,
|
|
end_pfn ? ((u64)end_pfn << PAGE_SHIFT) - 1 : 0);
|
|
calculate_node_totalpages(pgdat, start_pfn, end_pfn);
|
|
|
|
alloc_node_mem_map(pgdat);
|
|
pgdat_set_deferred_range(pgdat);
|
|
|
|
free_area_init_core(pgdat);
|
|
}
|
|
|
|
void __init free_area_init_memoryless_node(int nid)
|
|
{
|
|
free_area_init_node(nid);
|
|
}
|
|
|
|
#if MAX_NUMNODES > 1
|
|
/*
|
|
* Figure out the number of possible node ids.
|
|
*/
|
|
void __init setup_nr_node_ids(void)
|
|
{
|
|
unsigned int highest;
|
|
|
|
highest = find_last_bit(node_possible_map.bits, MAX_NUMNODES);
|
|
nr_node_ids = highest + 1;
|
|
}
|
|
#endif
|
|
|
|
/**
|
|
* node_map_pfn_alignment - determine the maximum internode alignment
|
|
*
|
|
* This function should be called after node map is populated and sorted.
|
|
* It calculates the maximum power of two alignment which can distinguish
|
|
* all the nodes.
|
|
*
|
|
* For example, if all nodes are 1GiB and aligned to 1GiB, the return value
|
|
* would indicate 1GiB alignment with (1 << (30 - PAGE_SHIFT)). If the
|
|
* nodes are shifted by 256MiB, 256MiB. Note that if only the last node is
|
|
* shifted, 1GiB is enough and this function will indicate so.
|
|
*
|
|
* This is used to test whether pfn -> nid mapping of the chosen memory
|
|
* model has fine enough granularity to avoid incorrect mapping for the
|
|
* populated node map.
|
|
*
|
|
* Return: the determined alignment in pfn's. 0 if there is no alignment
|
|
* requirement (single node).
|
|
*/
|
|
unsigned long __init node_map_pfn_alignment(void)
|
|
{
|
|
unsigned long accl_mask = 0, last_end = 0;
|
|
unsigned long start, end, mask;
|
|
int last_nid = NUMA_NO_NODE;
|
|
int i, nid;
|
|
|
|
for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, &nid) {
|
|
if (!start || last_nid < 0 || last_nid == nid) {
|
|
last_nid = nid;
|
|
last_end = end;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Start with a mask granular enough to pin-point to the
|
|
* start pfn and tick off bits one-by-one until it becomes
|
|
* too coarse to separate the current node from the last.
|
|
*/
|
|
mask = ~((1 << __ffs(start)) - 1);
|
|
while (mask && last_end <= (start & (mask << 1)))
|
|
mask <<= 1;
|
|
|
|
/* accumulate all internode masks */
|
|
accl_mask |= mask;
|
|
}
|
|
|
|
/* convert mask to number of pages */
|
|
return ~accl_mask + 1;
|
|
}
|
|
|
|
/**
|
|
* find_min_pfn_with_active_regions - Find the minimum PFN registered
|
|
*
|
|
* Return: the minimum PFN based on information provided via
|
|
* memblock_set_node().
|
|
*/
|
|
unsigned long __init find_min_pfn_with_active_regions(void)
|
|
{
|
|
return PHYS_PFN(memblock_start_of_DRAM());
|
|
}
|
|
|
|
/*
|
|
* early_calculate_totalpages()
|
|
* Sum pages in active regions for movable zone.
|
|
* Populate N_MEMORY for calculating usable_nodes.
|
|
*/
|
|
static unsigned long __init early_calculate_totalpages(void)
|
|
{
|
|
unsigned long totalpages = 0;
|
|
unsigned long start_pfn, end_pfn;
|
|
int i, nid;
|
|
|
|
for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) {
|
|
unsigned long pages = end_pfn - start_pfn;
|
|
|
|
totalpages += pages;
|
|
if (pages)
|
|
node_set_state(nid, N_MEMORY);
|
|
}
|
|
return totalpages;
|
|
}
|
|
|
|
/*
|
|
* Find the PFN the Movable zone begins in each node. Kernel memory
|
|
* is spread evenly between nodes as long as the nodes have enough
|
|
* memory. When they don't, some nodes will have more kernelcore than
|
|
* others
|
|
*/
|
|
static void __init find_zone_movable_pfns_for_nodes(void)
|
|
{
|
|
int i, nid;
|
|
unsigned long usable_startpfn;
|
|
unsigned long kernelcore_node, kernelcore_remaining;
|
|
/* save the state before borrow the nodemask */
|
|
nodemask_t saved_node_state = node_states[N_MEMORY];
|
|
unsigned long totalpages = early_calculate_totalpages();
|
|
int usable_nodes = nodes_weight(node_states[N_MEMORY]);
|
|
struct memblock_region *r;
|
|
|
|
/* Need to find movable_zone earlier when movable_node is specified. */
|
|
find_usable_zone_for_movable();
|
|
|
|
/*
|
|
* If movable_node is specified, ignore kernelcore and movablecore
|
|
* options.
|
|
*/
|
|
if (movable_node_is_enabled()) {
|
|
for_each_mem_region(r) {
|
|
if (!memblock_is_hotpluggable(r))
|
|
continue;
|
|
|
|
nid = memblock_get_region_node(r);
|
|
|
|
usable_startpfn = PFN_DOWN(r->base);
|
|
zone_movable_pfn[nid] = zone_movable_pfn[nid] ?
|
|
min(usable_startpfn, zone_movable_pfn[nid]) :
|
|
usable_startpfn;
|
|
}
|
|
|
|
goto out2;
|
|
}
|
|
|
|
/*
|
|
* If kernelcore=mirror is specified, ignore movablecore option
|
|
*/
|
|
if (mirrored_kernelcore) {
|
|
bool mem_below_4gb_not_mirrored = false;
|
|
|
|
for_each_mem_region(r) {
|
|
if (memblock_is_mirror(r))
|
|
continue;
|
|
|
|
nid = memblock_get_region_node(r);
|
|
|
|
usable_startpfn = memblock_region_memory_base_pfn(r);
|
|
|
|
if (usable_startpfn < 0x100000) {
|
|
mem_below_4gb_not_mirrored = true;
|
|
continue;
|
|
}
|
|
|
|
zone_movable_pfn[nid] = zone_movable_pfn[nid] ?
|
|
min(usable_startpfn, zone_movable_pfn[nid]) :
|
|
usable_startpfn;
|
|
}
|
|
|
|
if (mem_below_4gb_not_mirrored)
|
|
pr_warn("This configuration results in unmirrored kernel memory.\n");
|
|
|
|
goto out2;
|
|
}
|
|
|
|
/*
|
|
* If kernelcore=nn% or movablecore=nn% was specified, calculate the
|
|
* amount of necessary memory.
|
|
*/
|
|
if (required_kernelcore_percent)
|
|
required_kernelcore = (totalpages * 100 * required_kernelcore_percent) /
|
|
10000UL;
|
|
if (required_movablecore_percent)
|
|
required_movablecore = (totalpages * 100 * required_movablecore_percent) /
|
|
10000UL;
|
|
|
|
/*
|
|
* If movablecore= was specified, calculate what size of
|
|
* kernelcore that corresponds so that memory usable for
|
|
* any allocation type is evenly spread. If both kernelcore
|
|
* and movablecore are specified, then the value of kernelcore
|
|
* will be used for required_kernelcore if it's greater than
|
|
* what movablecore would have allowed.
|
|
*/
|
|
if (required_movablecore) {
|
|
unsigned long corepages;
|
|
|
|
/*
|
|
* Round-up so that ZONE_MOVABLE is at least as large as what
|
|
* was requested by the user
|
|
*/
|
|
required_movablecore =
|
|
roundup(required_movablecore, MAX_ORDER_NR_PAGES);
|
|
required_movablecore = min(totalpages, required_movablecore);
|
|
corepages = totalpages - required_movablecore;
|
|
|
|
required_kernelcore = max(required_kernelcore, corepages);
|
|
}
|
|
|
|
/*
|
|
* If kernelcore was not specified or kernelcore size is larger
|
|
* than totalpages, there is no ZONE_MOVABLE.
|
|
*/
|
|
if (!required_kernelcore || required_kernelcore >= totalpages)
|
|
goto out;
|
|
|
|
/* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
|
|
usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone];
|
|
|
|
restart:
|
|
/* Spread kernelcore memory as evenly as possible throughout nodes */
|
|
kernelcore_node = required_kernelcore / usable_nodes;
|
|
for_each_node_state(nid, N_MEMORY) {
|
|
unsigned long start_pfn, end_pfn;
|
|
|
|
/*
|
|
* Recalculate kernelcore_node if the division per node
|
|
* now exceeds what is necessary to satisfy the requested
|
|
* amount of memory for the kernel
|
|
*/
|
|
if (required_kernelcore < kernelcore_node)
|
|
kernelcore_node = required_kernelcore / usable_nodes;
|
|
|
|
/*
|
|
* As the map is walked, we track how much memory is usable
|
|
* by the kernel using kernelcore_remaining. When it is
|
|
* 0, the rest of the node is usable by ZONE_MOVABLE
|
|
*/
|
|
kernelcore_remaining = kernelcore_node;
|
|
|
|
/* Go through each range of PFNs within this node */
|
|
for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
|
|
unsigned long size_pages;
|
|
|
|
start_pfn = max(start_pfn, zone_movable_pfn[nid]);
|
|
if (start_pfn >= end_pfn)
|
|
continue;
|
|
|
|
/* Account for what is only usable for kernelcore */
|
|
if (start_pfn < usable_startpfn) {
|
|
unsigned long kernel_pages;
|
|
kernel_pages = min(end_pfn, usable_startpfn)
|
|
- start_pfn;
|
|
|
|
kernelcore_remaining -= min(kernel_pages,
|
|
kernelcore_remaining);
|
|
required_kernelcore -= min(kernel_pages,
|
|
required_kernelcore);
|
|
|
|
/* Continue if range is now fully accounted */
|
|
if (end_pfn <= usable_startpfn) {
|
|
|
|
/*
|
|
* Push zone_movable_pfn to the end so
|
|
* that if we have to rebalance
|
|
* kernelcore across nodes, we will
|
|
* not double account here
|
|
*/
|
|
zone_movable_pfn[nid] = end_pfn;
|
|
continue;
|
|
}
|
|
start_pfn = usable_startpfn;
|
|
}
|
|
|
|
/*
|
|
* The usable PFN range for ZONE_MOVABLE is from
|
|
* start_pfn->end_pfn. Calculate size_pages as the
|
|
* number of pages used as kernelcore
|
|
*/
|
|
size_pages = end_pfn - start_pfn;
|
|
if (size_pages > kernelcore_remaining)
|
|
size_pages = kernelcore_remaining;
|
|
zone_movable_pfn[nid] = start_pfn + size_pages;
|
|
|
|
/*
|
|
* Some kernelcore has been met, update counts and
|
|
* break if the kernelcore for this node has been
|
|
* satisfied
|
|
*/
|
|
required_kernelcore -= min(required_kernelcore,
|
|
size_pages);
|
|
kernelcore_remaining -= size_pages;
|
|
if (!kernelcore_remaining)
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If there is still required_kernelcore, we do another pass with one
|
|
* less node in the count. This will push zone_movable_pfn[nid] further
|
|
* along on the nodes that still have memory until kernelcore is
|
|
* satisfied
|
|
*/
|
|
usable_nodes--;
|
|
if (usable_nodes && required_kernelcore > usable_nodes)
|
|
goto restart;
|
|
|
|
out2:
|
|
/* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
|
|
for (nid = 0; nid < MAX_NUMNODES; nid++)
|
|
zone_movable_pfn[nid] =
|
|
roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES);
|
|
|
|
out:
|
|
/* restore the node_state */
|
|
node_states[N_MEMORY] = saved_node_state;
|
|
}
|
|
|
|
/* Any regular or high memory on that node ? */
|
|
static void check_for_memory(pg_data_t *pgdat, int nid)
|
|
{
|
|
enum zone_type zone_type;
|
|
|
|
for (zone_type = 0; zone_type <= ZONE_MOVABLE - 1; zone_type++) {
|
|
struct zone *zone = &pgdat->node_zones[zone_type];
|
|
if (populated_zone(zone)) {
|
|
if (IS_ENABLED(CONFIG_HIGHMEM))
|
|
node_set_state(nid, N_HIGH_MEMORY);
|
|
if (zone_type <= ZONE_NORMAL)
|
|
node_set_state(nid, N_NORMAL_MEMORY);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Some architecturs, e.g. ARC may have ZONE_HIGHMEM below ZONE_NORMAL. For
|
|
* such cases we allow max_zone_pfn sorted in the descending order
|
|
*/
|
|
bool __weak arch_has_descending_max_zone_pfns(void)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* free_area_init - Initialise all pg_data_t and zone data
|
|
* @max_zone_pfn: an array of max PFNs for each zone
|
|
*
|
|
* This will call free_area_init_node() for each active node in the system.
|
|
* Using the page ranges provided by memblock_set_node(), the size of each
|
|
* zone in each node and their holes is calculated. If the maximum PFN
|
|
* between two adjacent zones match, it is assumed that the zone is empty.
|
|
* For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
|
|
* that arch_max_dma32_pfn has no pages. It is also assumed that a zone
|
|
* starts where the previous one ended. For example, ZONE_DMA32 starts
|
|
* at arch_max_dma_pfn.
|
|
*/
|
|
void __init free_area_init(unsigned long *max_zone_pfn)
|
|
{
|
|
unsigned long start_pfn, end_pfn;
|
|
int i, nid, zone;
|
|
bool descending;
|
|
|
|
/* Record where the zone boundaries are */
|
|
memset(arch_zone_lowest_possible_pfn, 0,
|
|
sizeof(arch_zone_lowest_possible_pfn));
|
|
memset(arch_zone_highest_possible_pfn, 0,
|
|
sizeof(arch_zone_highest_possible_pfn));
|
|
|
|
start_pfn = find_min_pfn_with_active_regions();
|
|
descending = arch_has_descending_max_zone_pfns();
|
|
|
|
for (i = 0; i < MAX_NR_ZONES; i++) {
|
|
if (descending)
|
|
zone = MAX_NR_ZONES - i - 1;
|
|
else
|
|
zone = i;
|
|
|
|
if (zone == ZONE_MOVABLE)
|
|
continue;
|
|
|
|
end_pfn = max(max_zone_pfn[zone], start_pfn);
|
|
arch_zone_lowest_possible_pfn[zone] = start_pfn;
|
|
arch_zone_highest_possible_pfn[zone] = end_pfn;
|
|
|
|
start_pfn = end_pfn;
|
|
}
|
|
|
|
/* Find the PFNs that ZONE_MOVABLE begins at in each node */
|
|
memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn));
|
|
find_zone_movable_pfns_for_nodes();
|
|
|
|
/* Print out the zone ranges */
|
|
pr_info("Zone ranges:\n");
|
|
for (i = 0; i < MAX_NR_ZONES; i++) {
|
|
if (i == ZONE_MOVABLE)
|
|
continue;
|
|
pr_info(" %-8s ", zone_names[i]);
|
|
if (arch_zone_lowest_possible_pfn[i] ==
|
|
arch_zone_highest_possible_pfn[i])
|
|
pr_cont("empty\n");
|
|
else
|
|
pr_cont("[mem %#018Lx-%#018Lx]\n",
|
|
(u64)arch_zone_lowest_possible_pfn[i]
|
|
<< PAGE_SHIFT,
|
|
((u64)arch_zone_highest_possible_pfn[i]
|
|
<< PAGE_SHIFT) - 1);
|
|
}
|
|
|
|
/* Print out the PFNs ZONE_MOVABLE begins at in each node */
|
|
pr_info("Movable zone start for each node\n");
|
|
for (i = 0; i < MAX_NUMNODES; i++) {
|
|
if (zone_movable_pfn[i])
|
|
pr_info(" Node %d: %#018Lx\n", i,
|
|
(u64)zone_movable_pfn[i] << PAGE_SHIFT);
|
|
}
|
|
|
|
/*
|
|
* Print out the early node map, and initialize the
|
|
* subsection-map relative to active online memory ranges to
|
|
* enable future "sub-section" extensions of the memory map.
|
|
*/
|
|
pr_info("Early memory node ranges\n");
|
|
for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) {
|
|
pr_info(" node %3d: [mem %#018Lx-%#018Lx]\n", nid,
|
|
(u64)start_pfn << PAGE_SHIFT,
|
|
((u64)end_pfn << PAGE_SHIFT) - 1);
|
|
subsection_map_init(start_pfn, end_pfn - start_pfn);
|
|
}
|
|
|
|
/* Initialise every node */
|
|
mminit_verify_pageflags_layout();
|
|
setup_nr_node_ids();
|
|
for_each_online_node(nid) {
|
|
pg_data_t *pgdat = NODE_DATA(nid);
|
|
free_area_init_node(nid);
|
|
|
|
/* Any memory on that node */
|
|
if (pgdat->node_present_pages)
|
|
node_set_state(nid, N_MEMORY);
|
|
check_for_memory(pgdat, nid);
|
|
}
|
|
}
|
|
|
|
static int __init cmdline_parse_core(char *p, unsigned long *core,
|
|
unsigned long *percent)
|
|
{
|
|
unsigned long long coremem;
|
|
char *endptr;
|
|
|
|
if (!p)
|
|
return -EINVAL;
|
|
|
|
/* Value may be a percentage of total memory, otherwise bytes */
|
|
coremem = simple_strtoull(p, &endptr, 0);
|
|
if (*endptr == '%') {
|
|
/* Paranoid check for percent values greater than 100 */
|
|
WARN_ON(coremem > 100);
|
|
|
|
*percent = coremem;
|
|
} else {
|
|
coremem = memparse(p, &p);
|
|
/* Paranoid check that UL is enough for the coremem value */
|
|
WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX);
|
|
|
|
*core = coremem >> PAGE_SHIFT;
|
|
*percent = 0UL;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* kernelcore=size sets the amount of memory for use for allocations that
|
|
* cannot be reclaimed or migrated.
|
|
*/
|
|
static int __init cmdline_parse_kernelcore(char *p)
|
|
{
|
|
/* parse kernelcore=mirror */
|
|
if (parse_option_str(p, "mirror")) {
|
|
mirrored_kernelcore = true;
|
|
return 0;
|
|
}
|
|
|
|
return cmdline_parse_core(p, &required_kernelcore,
|
|
&required_kernelcore_percent);
|
|
}
|
|
|
|
/*
|
|
* movablecore=size sets the amount of memory for use for allocations that
|
|
* can be reclaimed or migrated.
|
|
*/
|
|
static int __init cmdline_parse_movablecore(char *p)
|
|
{
|
|
return cmdline_parse_core(p, &required_movablecore,
|
|
&required_movablecore_percent);
|
|
}
|
|
|
|
early_param("kernelcore", cmdline_parse_kernelcore);
|
|
early_param("movablecore", cmdline_parse_movablecore);
|
|
|
|
void adjust_managed_page_count(struct page *page, long count)
|
|
{
|
|
atomic_long_add(count, &page_zone(page)->managed_pages);
|
|
totalram_pages_add(count);
|
|
#ifdef CONFIG_HIGHMEM
|
|
if (PageHighMem(page))
|
|
totalhigh_pages_add(count);
|
|
#endif
|
|
}
|
|
EXPORT_SYMBOL(adjust_managed_page_count);
|
|
|
|
unsigned long free_reserved_area(void *start, void *end, int poison, const char *s)
|
|
{
|
|
void *pos;
|
|
unsigned long pages = 0;
|
|
|
|
start = (void *)PAGE_ALIGN((unsigned long)start);
|
|
end = (void *)((unsigned long)end & PAGE_MASK);
|
|
for (pos = start; pos < end; pos += PAGE_SIZE, pages++) {
|
|
struct page *page = virt_to_page(pos);
|
|
void *direct_map_addr;
|
|
|
|
/*
|
|
* 'direct_map_addr' might be different from 'pos'
|
|
* because some architectures' virt_to_page()
|
|
* work with aliases. Getting the direct map
|
|
* address ensures that we get a _writeable_
|
|
* alias for the memset().
|
|
*/
|
|
direct_map_addr = page_address(page);
|
|
/*
|
|
* Perform a kasan-unchecked memset() since this memory
|
|
* has not been initialized.
|
|
*/
|
|
direct_map_addr = kasan_reset_tag(direct_map_addr);
|
|
if ((unsigned int)poison <= 0xFF)
|
|
memset(direct_map_addr, poison, PAGE_SIZE);
|
|
|
|
free_reserved_page(page);
|
|
}
|
|
|
|
if (pages && s)
|
|
pr_info("Freeing %s memory: %ldK\n",
|
|
s, pages << (PAGE_SHIFT - 10));
|
|
|
|
return pages;
|
|
}
|
|
|
|
void __init mem_init_print_info(const char *str)
|
|
{
|
|
unsigned long physpages, codesize, datasize, rosize, bss_size;
|
|
unsigned long init_code_size, init_data_size;
|
|
|
|
physpages = get_num_physpages();
|
|
codesize = _etext - _stext;
|
|
datasize = _edata - _sdata;
|
|
rosize = __end_rodata - __start_rodata;
|
|
bss_size = __bss_stop - __bss_start;
|
|
init_data_size = __init_end - __init_begin;
|
|
init_code_size = _einittext - _sinittext;
|
|
|
|
/*
|
|
* Detect special cases and adjust section sizes accordingly:
|
|
* 1) .init.* may be embedded into .data sections
|
|
* 2) .init.text.* may be out of [__init_begin, __init_end],
|
|
* please refer to arch/tile/kernel/vmlinux.lds.S.
|
|
* 3) .rodata.* may be embedded into .text or .data sections.
|
|
*/
|
|
#define adj_init_size(start, end, size, pos, adj) \
|
|
do { \
|
|
if (start <= pos && pos < end && size > adj) \
|
|
size -= adj; \
|
|
} while (0)
|
|
|
|
adj_init_size(__init_begin, __init_end, init_data_size,
|
|
_sinittext, init_code_size);
|
|
adj_init_size(_stext, _etext, codesize, _sinittext, init_code_size);
|
|
adj_init_size(_sdata, _edata, datasize, __init_begin, init_data_size);
|
|
adj_init_size(_stext, _etext, codesize, __start_rodata, rosize);
|
|
adj_init_size(_sdata, _edata, datasize, __start_rodata, rosize);
|
|
|
|
#undef adj_init_size
|
|
|
|
pr_info("Memory: %luK/%luK available (%luK kernel code, %luK rwdata, %luK rodata, %luK init, %luK bss, %luK reserved, %luK cma-reserved"
|
|
#ifdef CONFIG_HIGHMEM
|
|
", %luK highmem"
|
|
#endif
|
|
"%s%s)\n",
|
|
nr_free_pages() << (PAGE_SHIFT - 10),
|
|
physpages << (PAGE_SHIFT - 10),
|
|
codesize >> 10, datasize >> 10, rosize >> 10,
|
|
(init_data_size + init_code_size) >> 10, bss_size >> 10,
|
|
(physpages - totalram_pages() - totalcma_pages) << (PAGE_SHIFT - 10),
|
|
totalcma_pages << (PAGE_SHIFT - 10),
|
|
#ifdef CONFIG_HIGHMEM
|
|
totalhigh_pages() << (PAGE_SHIFT - 10),
|
|
#endif
|
|
str ? ", " : "", str ? str : "");
|
|
}
|
|
|
|
/**
|
|
* set_dma_reserve - set the specified number of pages reserved in the first zone
|
|
* @new_dma_reserve: The number of pages to mark reserved
|
|
*
|
|
* The per-cpu batchsize and zone watermarks are determined by managed_pages.
|
|
* In the DMA zone, a significant percentage may be consumed by kernel image
|
|
* and other unfreeable allocations which can skew the watermarks badly. This
|
|
* function may optionally be used to account for unfreeable pages in the
|
|
* first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
|
|
* smaller per-cpu batchsize.
|
|
*/
|
|
void __init set_dma_reserve(unsigned long new_dma_reserve)
|
|
{
|
|
dma_reserve = new_dma_reserve;
|
|
}
|
|
|
|
static int page_alloc_cpu_dead(unsigned int cpu)
|
|
{
|
|
|
|
lru_add_drain_cpu(cpu);
|
|
drain_pages(cpu);
|
|
|
|
/*
|
|
* Spill the event counters of the dead processor
|
|
* into the current processors event counters.
|
|
* This artificially elevates the count of the current
|
|
* processor.
|
|
*/
|
|
vm_events_fold_cpu(cpu);
|
|
|
|
/*
|
|
* Zero the differential counters of the dead processor
|
|
* so that the vm statistics are consistent.
|
|
*
|
|
* This is only okay since the processor is dead and cannot
|
|
* race with what we are doing.
|
|
*/
|
|
cpu_vm_stats_fold(cpu);
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA
|
|
int hashdist = HASHDIST_DEFAULT;
|
|
|
|
static int __init set_hashdist(char *str)
|
|
{
|
|
if (!str)
|
|
return 0;
|
|
hashdist = simple_strtoul(str, &str, 0);
|
|
return 1;
|
|
}
|
|
__setup("hashdist=", set_hashdist);
|
|
#endif
|
|
|
|
void __init page_alloc_init(void)
|
|
{
|
|
int ret;
|
|
|
|
#ifdef CONFIG_NUMA
|
|
if (num_node_state(N_MEMORY) == 1)
|
|
hashdist = 0;
|
|
#endif
|
|
|
|
ret = cpuhp_setup_state_nocalls(CPUHP_PAGE_ALLOC_DEAD,
|
|
"mm/page_alloc:dead", NULL,
|
|
page_alloc_cpu_dead);
|
|
WARN_ON(ret < 0);
|
|
}
|
|
|
|
/*
|
|
* calculate_totalreserve_pages - called when sysctl_lowmem_reserve_ratio
|
|
* or min_free_kbytes changes.
|
|
*/
|
|
static void calculate_totalreserve_pages(void)
|
|
{
|
|
struct pglist_data *pgdat;
|
|
unsigned long reserve_pages = 0;
|
|
enum zone_type i, j;
|
|
|
|
for_each_online_pgdat(pgdat) {
|
|
|
|
pgdat->totalreserve_pages = 0;
|
|
|
|
for (i = 0; i < MAX_NR_ZONES; i++) {
|
|
struct zone *zone = pgdat->node_zones + i;
|
|
long max = 0;
|
|
unsigned long managed_pages = zone_managed_pages(zone);
|
|
|
|
/* Find valid and maximum lowmem_reserve in the zone */
|
|
for (j = i; j < MAX_NR_ZONES; j++) {
|
|
if (zone->lowmem_reserve[j] > max)
|
|
max = zone->lowmem_reserve[j];
|
|
}
|
|
|
|
/* we treat the high watermark as reserved pages. */
|
|
max += high_wmark_pages(zone);
|
|
|
|
if (max > managed_pages)
|
|
max = managed_pages;
|
|
|
|
pgdat->totalreserve_pages += max;
|
|
|
|
reserve_pages += max;
|
|
}
|
|
}
|
|
totalreserve_pages = reserve_pages;
|
|
}
|
|
|
|
/*
|
|
* setup_per_zone_lowmem_reserve - called whenever
|
|
* sysctl_lowmem_reserve_ratio changes. Ensures that each zone
|
|
* has a correct pages reserved value, so an adequate number of
|
|
* pages are left in the zone after a successful __alloc_pages().
|
|
*/
|
|
static void setup_per_zone_lowmem_reserve(void)
|
|
{
|
|
struct pglist_data *pgdat;
|
|
enum zone_type i, j;
|
|
|
|
for_each_online_pgdat(pgdat) {
|
|
for (i = 0; i < MAX_NR_ZONES - 1; i++) {
|
|
struct zone *zone = &pgdat->node_zones[i];
|
|
int ratio = sysctl_lowmem_reserve_ratio[i];
|
|
bool clear = !ratio || !zone_managed_pages(zone);
|
|
unsigned long managed_pages = 0;
|
|
|
|
for (j = i + 1; j < MAX_NR_ZONES; j++) {
|
|
if (clear) {
|
|
zone->lowmem_reserve[j] = 0;
|
|
} else {
|
|
struct zone *upper_zone = &pgdat->node_zones[j];
|
|
|
|
managed_pages += zone_managed_pages(upper_zone);
|
|
zone->lowmem_reserve[j] = managed_pages / ratio;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* update totalreserve_pages */
|
|
calculate_totalreserve_pages();
|
|
}
|
|
|
|
static void __setup_per_zone_wmarks(void)
|
|
{
|
|
unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10);
|
|
unsigned long lowmem_pages = 0;
|
|
struct zone *zone;
|
|
unsigned long flags;
|
|
|
|
/* Calculate total number of !ZONE_HIGHMEM pages */
|
|
for_each_zone(zone) {
|
|
if (!is_highmem(zone))
|
|
lowmem_pages += zone_managed_pages(zone);
|
|
}
|
|
|
|
for_each_zone(zone) {
|
|
u64 tmp;
|
|
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
tmp = (u64)pages_min * zone_managed_pages(zone);
|
|
do_div(tmp, lowmem_pages);
|
|
if (is_highmem(zone)) {
|
|
/*
|
|
* __GFP_HIGH and PF_MEMALLOC allocations usually don't
|
|
* need highmem pages, so cap pages_min to a small
|
|
* value here.
|
|
*
|
|
* The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
|
|
* deltas control async page reclaim, and so should
|
|
* not be capped for highmem.
|
|
*/
|
|
unsigned long min_pages;
|
|
|
|
min_pages = zone_managed_pages(zone) / 1024;
|
|
min_pages = clamp(min_pages, SWAP_CLUSTER_MAX, 128UL);
|
|
zone->_watermark[WMARK_MIN] = min_pages;
|
|
} else {
|
|
/*
|
|
* If it's a lowmem zone, reserve a number of pages
|
|
* proportionate to the zone's size.
|
|
*/
|
|
zone->_watermark[WMARK_MIN] = tmp;
|
|
}
|
|
|
|
/*
|
|
* Set the kswapd watermarks distance according to the
|
|
* scale factor in proportion to available memory, but
|
|
* ensure a minimum size on small systems.
|
|
*/
|
|
tmp = max_t(u64, tmp >> 2,
|
|
mult_frac(zone_managed_pages(zone),
|
|
watermark_scale_factor, 10000));
|
|
|
|
zone->watermark_boost = 0;
|
|
zone->_watermark[WMARK_LOW] = min_wmark_pages(zone) + tmp;
|
|
zone->_watermark[WMARK_HIGH] = min_wmark_pages(zone) + tmp * 2;
|
|
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
}
|
|
|
|
/* update totalreserve_pages */
|
|
calculate_totalreserve_pages();
|
|
}
|
|
|
|
/**
|
|
* setup_per_zone_wmarks - called when min_free_kbytes changes
|
|
* or when memory is hot-{added|removed}
|
|
*
|
|
* Ensures that the watermark[min,low,high] values for each zone are set
|
|
* correctly with respect to min_free_kbytes.
|
|
*/
|
|
void setup_per_zone_wmarks(void)
|
|
{
|
|
static DEFINE_SPINLOCK(lock);
|
|
|
|
spin_lock(&lock);
|
|
__setup_per_zone_wmarks();
|
|
spin_unlock(&lock);
|
|
}
|
|
|
|
/*
|
|
* Initialise min_free_kbytes.
|
|
*
|
|
* For small machines we want it small (128k min). For large machines
|
|
* we want it large (256MB max). But it is not linear, because network
|
|
* bandwidth does not increase linearly with machine size. We use
|
|
*
|
|
* min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
|
|
* min_free_kbytes = sqrt(lowmem_kbytes * 16)
|
|
*
|
|
* which yields
|
|
*
|
|
* 16MB: 512k
|
|
* 32MB: 724k
|
|
* 64MB: 1024k
|
|
* 128MB: 1448k
|
|
* 256MB: 2048k
|
|
* 512MB: 2896k
|
|
* 1024MB: 4096k
|
|
* 2048MB: 5792k
|
|
* 4096MB: 8192k
|
|
* 8192MB: 11584k
|
|
* 16384MB: 16384k
|
|
*/
|
|
int __meminit init_per_zone_wmark_min(void)
|
|
{
|
|
unsigned long lowmem_kbytes;
|
|
int new_min_free_kbytes;
|
|
|
|
lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10);
|
|
new_min_free_kbytes = int_sqrt(lowmem_kbytes * 16);
|
|
|
|
if (new_min_free_kbytes > user_min_free_kbytes) {
|
|
min_free_kbytes = new_min_free_kbytes;
|
|
if (min_free_kbytes < 128)
|
|
min_free_kbytes = 128;
|
|
if (min_free_kbytes > 262144)
|
|
min_free_kbytes = 262144;
|
|
} else {
|
|
pr_warn("min_free_kbytes is not updated to %d because user defined value %d is preferred\n",
|
|
new_min_free_kbytes, user_min_free_kbytes);
|
|
}
|
|
setup_per_zone_wmarks();
|
|
refresh_zone_stat_thresholds();
|
|
setup_per_zone_lowmem_reserve();
|
|
|
|
#ifdef CONFIG_NUMA
|
|
setup_min_unmapped_ratio();
|
|
setup_min_slab_ratio();
|
|
#endif
|
|
|
|
khugepaged_min_free_kbytes_update();
|
|
|
|
return 0;
|
|
}
|
|
postcore_initcall(init_per_zone_wmark_min)
|
|
|
|
/*
|
|
* min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
|
|
* that we can call two helper functions whenever min_free_kbytes
|
|
* changes.
|
|
*/
|
|
int min_free_kbytes_sysctl_handler(struct ctl_table *table, int write,
|
|
void *buffer, size_t *length, loff_t *ppos)
|
|
{
|
|
int rc;
|
|
|
|
rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
|
|
if (rc)
|
|
return rc;
|
|
|
|
if (write) {
|
|
user_min_free_kbytes = min_free_kbytes;
|
|
setup_per_zone_wmarks();
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int watermark_scale_factor_sysctl_handler(struct ctl_table *table, int write,
|
|
void *buffer, size_t *length, loff_t *ppos)
|
|
{
|
|
int rc;
|
|
|
|
rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
|
|
if (rc)
|
|
return rc;
|
|
|
|
if (write)
|
|
setup_per_zone_wmarks();
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA
|
|
static void setup_min_unmapped_ratio(void)
|
|
{
|
|
pg_data_t *pgdat;
|
|
struct zone *zone;
|
|
|
|
for_each_online_pgdat(pgdat)
|
|
pgdat->min_unmapped_pages = 0;
|
|
|
|
for_each_zone(zone)
|
|
zone->zone_pgdat->min_unmapped_pages += (zone_managed_pages(zone) *
|
|
sysctl_min_unmapped_ratio) / 100;
|
|
}
|
|
|
|
|
|
int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *table, int write,
|
|
void *buffer, size_t *length, loff_t *ppos)
|
|
{
|
|
int rc;
|
|
|
|
rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
|
|
if (rc)
|
|
return rc;
|
|
|
|
setup_min_unmapped_ratio();
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void setup_min_slab_ratio(void)
|
|
{
|
|
pg_data_t *pgdat;
|
|
struct zone *zone;
|
|
|
|
for_each_online_pgdat(pgdat)
|
|
pgdat->min_slab_pages = 0;
|
|
|
|
for_each_zone(zone)
|
|
zone->zone_pgdat->min_slab_pages += (zone_managed_pages(zone) *
|
|
sysctl_min_slab_ratio) / 100;
|
|
}
|
|
|
|
int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *table, int write,
|
|
void *buffer, size_t *length, loff_t *ppos)
|
|
{
|
|
int rc;
|
|
|
|
rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
|
|
if (rc)
|
|
return rc;
|
|
|
|
setup_min_slab_ratio();
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* lowmem_reserve_ratio_sysctl_handler - just a wrapper around
|
|
* proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
|
|
* whenever sysctl_lowmem_reserve_ratio changes.
|
|
*
|
|
* The reserve ratio obviously has absolutely no relation with the
|
|
* minimum watermarks. The lowmem reserve ratio can only make sense
|
|
* if in function of the boot time zone sizes.
|
|
*/
|
|
int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *table, int write,
|
|
void *buffer, size_t *length, loff_t *ppos)
|
|
{
|
|
int i;
|
|
|
|
proc_dointvec_minmax(table, write, buffer, length, ppos);
|
|
|
|
for (i = 0; i < MAX_NR_ZONES; i++) {
|
|
if (sysctl_lowmem_reserve_ratio[i] < 1)
|
|
sysctl_lowmem_reserve_ratio[i] = 0;
|
|
}
|
|
|
|
setup_per_zone_lowmem_reserve();
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* percpu_pagelist_fraction - changes the pcp->high for each zone on each
|
|
* cpu. It is the fraction of total pages in each zone that a hot per cpu
|
|
* pagelist can have before it gets flushed back to buddy allocator.
|
|
*/
|
|
int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *table, int write,
|
|
void *buffer, size_t *length, loff_t *ppos)
|
|
{
|
|
struct zone *zone;
|
|
int old_percpu_pagelist_fraction;
|
|
int ret;
|
|
|
|
mutex_lock(&pcp_batch_high_lock);
|
|
old_percpu_pagelist_fraction = percpu_pagelist_fraction;
|
|
|
|
ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
|
|
if (!write || ret < 0)
|
|
goto out;
|
|
|
|
/* Sanity checking to avoid pcp imbalance */
|
|
if (percpu_pagelist_fraction &&
|
|
percpu_pagelist_fraction < MIN_PERCPU_PAGELIST_FRACTION) {
|
|
percpu_pagelist_fraction = old_percpu_pagelist_fraction;
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
/* No change? */
|
|
if (percpu_pagelist_fraction == old_percpu_pagelist_fraction)
|
|
goto out;
|
|
|
|
for_each_populated_zone(zone)
|
|
zone_set_pageset_high_and_batch(zone);
|
|
out:
|
|
mutex_unlock(&pcp_batch_high_lock);
|
|
return ret;
|
|
}
|
|
|
|
#ifndef __HAVE_ARCH_RESERVED_KERNEL_PAGES
|
|
/*
|
|
* Returns the number of pages that arch has reserved but
|
|
* is not known to alloc_large_system_hash().
|
|
*/
|
|
static unsigned long __init arch_reserved_kernel_pages(void)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Adaptive scale is meant to reduce sizes of hash tables on large memory
|
|
* machines. As memory size is increased the scale is also increased but at
|
|
* slower pace. Starting from ADAPT_SCALE_BASE (64G), every time memory
|
|
* quadruples the scale is increased by one, which means the size of hash table
|
|
* only doubles, instead of quadrupling as well.
|
|
* Because 32-bit systems cannot have large physical memory, where this scaling
|
|
* makes sense, it is disabled on such platforms.
|
|
*/
|
|
#if __BITS_PER_LONG > 32
|
|
#define ADAPT_SCALE_BASE (64ul << 30)
|
|
#define ADAPT_SCALE_SHIFT 2
|
|
#define ADAPT_SCALE_NPAGES (ADAPT_SCALE_BASE >> PAGE_SHIFT)
|
|
#endif
|
|
|
|
/*
|
|
* allocate a large system hash table from bootmem
|
|
* - it is assumed that the hash table must contain an exact power-of-2
|
|
* quantity of entries
|
|
* - limit is the number of hash buckets, not the total allocation size
|
|
*/
|
|
void *__init alloc_large_system_hash(const char *tablename,
|
|
unsigned long bucketsize,
|
|
unsigned long numentries,
|
|
int scale,
|
|
int flags,
|
|
unsigned int *_hash_shift,
|
|
unsigned int *_hash_mask,
|
|
unsigned long low_limit,
|
|
unsigned long high_limit)
|
|
{
|
|
unsigned long long max = high_limit;
|
|
unsigned long log2qty, size;
|
|
void *table = NULL;
|
|
gfp_t gfp_flags;
|
|
bool virt;
|
|
|
|
/* allow the kernel cmdline to have a say */
|
|
if (!numentries) {
|
|
/* round applicable memory size up to nearest megabyte */
|
|
numentries = nr_kernel_pages;
|
|
numentries -= arch_reserved_kernel_pages();
|
|
|
|
/* It isn't necessary when PAGE_SIZE >= 1MB */
|
|
if (PAGE_SHIFT < 20)
|
|
numentries = round_up(numentries, (1<<20)/PAGE_SIZE);
|
|
|
|
#if __BITS_PER_LONG > 32
|
|
if (!high_limit) {
|
|
unsigned long adapt;
|
|
|
|
for (adapt = ADAPT_SCALE_NPAGES; adapt < numentries;
|
|
adapt <<= ADAPT_SCALE_SHIFT)
|
|
scale++;
|
|
}
|
|
#endif
|
|
|
|
/* limit to 1 bucket per 2^scale bytes of low memory */
|
|
if (scale > PAGE_SHIFT)
|
|
numentries >>= (scale - PAGE_SHIFT);
|
|
else
|
|
numentries <<= (PAGE_SHIFT - scale);
|
|
|
|
/* Make sure we've got at least a 0-order allocation.. */
|
|
if (unlikely(flags & HASH_SMALL)) {
|
|
/* Makes no sense without HASH_EARLY */
|
|
WARN_ON(!(flags & HASH_EARLY));
|
|
if (!(numentries >> *_hash_shift)) {
|
|
numentries = 1UL << *_hash_shift;
|
|
BUG_ON(!numentries);
|
|
}
|
|
} else if (unlikely((numentries * bucketsize) < PAGE_SIZE))
|
|
numentries = PAGE_SIZE / bucketsize;
|
|
}
|
|
numentries = roundup_pow_of_two(numentries);
|
|
|
|
/* limit allocation size to 1/16 total memory by default */
|
|
if (max == 0) {
|
|
max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4;
|
|
do_div(max, bucketsize);
|
|
}
|
|
max = min(max, 0x80000000ULL);
|
|
|
|
if (numentries < low_limit)
|
|
numentries = low_limit;
|
|
if (numentries > max)
|
|
numentries = max;
|
|
|
|
log2qty = ilog2(numentries);
|
|
|
|
gfp_flags = (flags & HASH_ZERO) ? GFP_ATOMIC | __GFP_ZERO : GFP_ATOMIC;
|
|
do {
|
|
virt = false;
|
|
size = bucketsize << log2qty;
|
|
if (flags & HASH_EARLY) {
|
|
if (flags & HASH_ZERO)
|
|
table = memblock_alloc(size, SMP_CACHE_BYTES);
|
|
else
|
|
table = memblock_alloc_raw(size,
|
|
SMP_CACHE_BYTES);
|
|
} else if (get_order(size) >= MAX_ORDER || hashdist) {
|
|
table = __vmalloc(size, gfp_flags);
|
|
virt = true;
|
|
} else {
|
|
/*
|
|
* If bucketsize is not a power-of-two, we may free
|
|
* some pages at the end of hash table which
|
|
* alloc_pages_exact() automatically does
|
|
*/
|
|
table = alloc_pages_exact(size, gfp_flags);
|
|
kmemleak_alloc(table, size, 1, gfp_flags);
|
|
}
|
|
} while (!table && size > PAGE_SIZE && --log2qty);
|
|
|
|
if (!table)
|
|
panic("Failed to allocate %s hash table\n", tablename);
|
|
|
|
pr_info("%s hash table entries: %ld (order: %d, %lu bytes, %s)\n",
|
|
tablename, 1UL << log2qty, ilog2(size) - PAGE_SHIFT, size,
|
|
virt ? "vmalloc" : "linear");
|
|
|
|
if (_hash_shift)
|
|
*_hash_shift = log2qty;
|
|
if (_hash_mask)
|
|
*_hash_mask = (1 << log2qty) - 1;
|
|
|
|
return table;
|
|
}
|
|
|
|
/*
|
|
* This function checks whether pageblock includes unmovable pages or not.
|
|
*
|
|
* PageLRU check without isolation or lru_lock could race so that
|
|
* MIGRATE_MOVABLE block might include unmovable pages. And __PageMovable
|
|
* check without lock_page also may miss some movable non-lru pages at
|
|
* race condition. So you can't expect this function should be exact.
|
|
*
|
|
* Returns a page without holding a reference. If the caller wants to
|
|
* dereference that page (e.g., dumping), it has to make sure that it
|
|
* cannot get removed (e.g., via memory unplug) concurrently.
|
|
*
|
|
*/
|
|
struct page *has_unmovable_pages(struct zone *zone, struct page *page,
|
|
int migratetype, int flags)
|
|
{
|
|
unsigned long iter = 0;
|
|
unsigned long pfn = page_to_pfn(page);
|
|
unsigned long offset = pfn % pageblock_nr_pages;
|
|
|
|
if (is_migrate_cma_page(page)) {
|
|
/*
|
|
* CMA allocations (alloc_contig_range) really need to mark
|
|
* isolate CMA pageblocks even when they are not movable in fact
|
|
* so consider them movable here.
|
|
*/
|
|
if (is_migrate_cma(migratetype))
|
|
return NULL;
|
|
|
|
return page;
|
|
}
|
|
|
|
for (; iter < pageblock_nr_pages - offset; iter++) {
|
|
if (!pfn_valid_within(pfn + iter))
|
|
continue;
|
|
|
|
page = pfn_to_page(pfn + iter);
|
|
|
|
/*
|
|
* Both, bootmem allocations and memory holes are marked
|
|
* PG_reserved and are unmovable. We can even have unmovable
|
|
* allocations inside ZONE_MOVABLE, for example when
|
|
* specifying "movablecore".
|
|
*/
|
|
if (PageReserved(page))
|
|
return page;
|
|
|
|
/*
|
|
* If the zone is movable and we have ruled out all reserved
|
|
* pages then it should be reasonably safe to assume the rest
|
|
* is movable.
|
|
*/
|
|
if (zone_idx(zone) == ZONE_MOVABLE)
|
|
continue;
|
|
|
|
/*
|
|
* Hugepages are not in LRU lists, but they're movable.
|
|
* THPs are on the LRU, but need to be counted as #small pages.
|
|
* We need not scan over tail pages because we don't
|
|
* handle each tail page individually in migration.
|
|
*/
|
|
if (PageHuge(page) || PageTransCompound(page)) {
|
|
struct page *head = compound_head(page);
|
|
unsigned int skip_pages;
|
|
|
|
if (PageHuge(page)) {
|
|
if (!hugepage_migration_supported(page_hstate(head)))
|
|
return page;
|
|
} else if (!PageLRU(head) && !__PageMovable(head)) {
|
|
return page;
|
|
}
|
|
|
|
skip_pages = compound_nr(head) - (page - head);
|
|
iter += skip_pages - 1;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* We can't use page_count without pin a page
|
|
* because another CPU can free compound page.
|
|
* This check already skips compound tails of THP
|
|
* because their page->_refcount is zero at all time.
|
|
*/
|
|
if (!page_ref_count(page)) {
|
|
if (PageBuddy(page))
|
|
iter += (1 << buddy_order(page)) - 1;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* The HWPoisoned page may be not in buddy system, and
|
|
* page_count() is not 0.
|
|
*/
|
|
if ((flags & MEMORY_OFFLINE) && PageHWPoison(page))
|
|
continue;
|
|
|
|
/*
|
|
* We treat all PageOffline() pages as movable when offlining
|
|
* to give drivers a chance to decrement their reference count
|
|
* in MEM_GOING_OFFLINE in order to indicate that these pages
|
|
* can be offlined as there are no direct references anymore.
|
|
* For actually unmovable PageOffline() where the driver does
|
|
* not support this, we will fail later when trying to actually
|
|
* move these pages that still have a reference count > 0.
|
|
* (false negatives in this function only)
|
|
*/
|
|
if ((flags & MEMORY_OFFLINE) && PageOffline(page))
|
|
continue;
|
|
|
|
if (__PageMovable(page) || PageLRU(page))
|
|
continue;
|
|
|
|
/*
|
|
* If there are RECLAIMABLE pages, we need to check
|
|
* it. But now, memory offline itself doesn't call
|
|
* shrink_node_slabs() and it still to be fixed.
|
|
*/
|
|
return page;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
#ifdef CONFIG_CONTIG_ALLOC
|
|
static unsigned long pfn_max_align_down(unsigned long pfn)
|
|
{
|
|
return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES,
|
|
pageblock_nr_pages) - 1);
|
|
}
|
|
|
|
static unsigned long pfn_max_align_up(unsigned long pfn)
|
|
{
|
|
return ALIGN(pfn, max_t(unsigned long, MAX_ORDER_NR_PAGES,
|
|
pageblock_nr_pages));
|
|
}
|
|
|
|
/* [start, end) must belong to a single zone. */
|
|
static int __alloc_contig_migrate_range(struct compact_control *cc,
|
|
unsigned long start, unsigned long end)
|
|
{
|
|
/* This function is based on compact_zone() from compaction.c. */
|
|
unsigned int nr_reclaimed;
|
|
unsigned long pfn = start;
|
|
unsigned int tries = 0;
|
|
int ret = 0;
|
|
struct migration_target_control mtc = {
|
|
.nid = zone_to_nid(cc->zone),
|
|
.gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_RETRY_MAYFAIL,
|
|
};
|
|
|
|
migrate_prep();
|
|
|
|
while (pfn < end || !list_empty(&cc->migratepages)) {
|
|
if (fatal_signal_pending(current)) {
|
|
ret = -EINTR;
|
|
break;
|
|
}
|
|
|
|
if (list_empty(&cc->migratepages)) {
|
|
cc->nr_migratepages = 0;
|
|
pfn = isolate_migratepages_range(cc, pfn, end);
|
|
if (!pfn) {
|
|
ret = -EINTR;
|
|
break;
|
|
}
|
|
tries = 0;
|
|
} else if (++tries == 5) {
|
|
ret = ret < 0 ? ret : -EBUSY;
|
|
break;
|
|
}
|
|
|
|
nr_reclaimed = reclaim_clean_pages_from_list(cc->zone,
|
|
&cc->migratepages);
|
|
cc->nr_migratepages -= nr_reclaimed;
|
|
|
|
ret = migrate_pages(&cc->migratepages, alloc_migration_target,
|
|
NULL, (unsigned long)&mtc, cc->mode, MR_CONTIG_RANGE);
|
|
}
|
|
if (ret < 0) {
|
|
putback_movable_pages(&cc->migratepages);
|
|
return ret;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* alloc_contig_range() -- tries to allocate given range of pages
|
|
* @start: start PFN to allocate
|
|
* @end: one-past-the-last PFN to allocate
|
|
* @migratetype: migratetype of the underlaying pageblocks (either
|
|
* #MIGRATE_MOVABLE or #MIGRATE_CMA). All pageblocks
|
|
* in range must have the same migratetype and it must
|
|
* be either of the two.
|
|
* @gfp_mask: GFP mask to use during compaction
|
|
*
|
|
* The PFN range does not have to be pageblock or MAX_ORDER_NR_PAGES
|
|
* aligned. The PFN range must belong to a single zone.
|
|
*
|
|
* The first thing this routine does is attempt to MIGRATE_ISOLATE all
|
|
* pageblocks in the range. Once isolated, the pageblocks should not
|
|
* be modified by others.
|
|
*
|
|
* Return: zero on success or negative error code. On success all
|
|
* pages which PFN is in [start, end) are allocated for the caller and
|
|
* need to be freed with free_contig_range().
|
|
*/
|
|
int alloc_contig_range(unsigned long start, unsigned long end,
|
|
unsigned migratetype, gfp_t gfp_mask)
|
|
{
|
|
unsigned long outer_start, outer_end;
|
|
unsigned int order;
|
|
int ret = 0;
|
|
|
|
struct compact_control cc = {
|
|
.nr_migratepages = 0,
|
|
.order = -1,
|
|
.zone = page_zone(pfn_to_page(start)),
|
|
.mode = MIGRATE_SYNC,
|
|
.ignore_skip_hint = true,
|
|
.no_set_skip_hint = true,
|
|
.gfp_mask = current_gfp_context(gfp_mask),
|
|
.alloc_contig = true,
|
|
};
|
|
INIT_LIST_HEAD(&cc.migratepages);
|
|
|
|
/*
|
|
* What we do here is we mark all pageblocks in range as
|
|
* MIGRATE_ISOLATE. Because pageblock and max order pages may
|
|
* have different sizes, and due to the way page allocator
|
|
* work, we align the range to biggest of the two pages so
|
|
* that page allocator won't try to merge buddies from
|
|
* different pageblocks and change MIGRATE_ISOLATE to some
|
|
* other migration type.
|
|
*
|
|
* Once the pageblocks are marked as MIGRATE_ISOLATE, we
|
|
* migrate the pages from an unaligned range (ie. pages that
|
|
* we are interested in). This will put all the pages in
|
|
* range back to page allocator as MIGRATE_ISOLATE.
|
|
*
|
|
* When this is done, we take the pages in range from page
|
|
* allocator removing them from the buddy system. This way
|
|
* page allocator will never consider using them.
|
|
*
|
|
* This lets us mark the pageblocks back as
|
|
* MIGRATE_CMA/MIGRATE_MOVABLE so that free pages in the
|
|
* aligned range but not in the unaligned, original range are
|
|
* put back to page allocator so that buddy can use them.
|
|
*/
|
|
|
|
ret = start_isolate_page_range(pfn_max_align_down(start),
|
|
pfn_max_align_up(end), migratetype, 0);
|
|
if (ret)
|
|
return ret;
|
|
|
|
drain_all_pages(cc.zone);
|
|
|
|
/*
|
|
* In case of -EBUSY, we'd like to know which page causes problem.
|
|
* So, just fall through. test_pages_isolated() has a tracepoint
|
|
* which will report the busy page.
|
|
*
|
|
* It is possible that busy pages could become available before
|
|
* the call to test_pages_isolated, and the range will actually be
|
|
* allocated. So, if we fall through be sure to clear ret so that
|
|
* -EBUSY is not accidentally used or returned to caller.
|
|
*/
|
|
ret = __alloc_contig_migrate_range(&cc, start, end);
|
|
if (ret && ret != -EBUSY)
|
|
goto done;
|
|
ret =0;
|
|
|
|
/*
|
|
* Pages from [start, end) are within a MAX_ORDER_NR_PAGES
|
|
* aligned blocks that are marked as MIGRATE_ISOLATE. What's
|
|
* more, all pages in [start, end) are free in page allocator.
|
|
* What we are going to do is to allocate all pages from
|
|
* [start, end) (that is remove them from page allocator).
|
|
*
|
|
* The only problem is that pages at the beginning and at the
|
|
* end of interesting range may be not aligned with pages that
|
|
* page allocator holds, ie. they can be part of higher order
|
|
* pages. Because of this, we reserve the bigger range and
|
|
* once this is done free the pages we are not interested in.
|
|
*
|
|
* We don't have to hold zone->lock here because the pages are
|
|
* isolated thus they won't get removed from buddy.
|
|
*/
|
|
|
|
lru_add_drain_all();
|
|
|
|
order = 0;
|
|
outer_start = start;
|
|
while (!PageBuddy(pfn_to_page(outer_start))) {
|
|
if (++order >= MAX_ORDER) {
|
|
outer_start = start;
|
|
break;
|
|
}
|
|
outer_start &= ~0UL << order;
|
|
}
|
|
|
|
if (outer_start != start) {
|
|
order = buddy_order(pfn_to_page(outer_start));
|
|
|
|
/*
|
|
* outer_start page could be small order buddy page and
|
|
* it doesn't include start page. Adjust outer_start
|
|
* in this case to report failed page properly
|
|
* on tracepoint in test_pages_isolated()
|
|
*/
|
|
if (outer_start + (1UL << order) <= start)
|
|
outer_start = start;
|
|
}
|
|
|
|
/* Make sure the range is really isolated. */
|
|
if (test_pages_isolated(outer_start, end, 0)) {
|
|
pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n",
|
|
__func__, outer_start, end);
|
|
ret = -EBUSY;
|
|
goto done;
|
|
}
|
|
|
|
/* Grab isolated pages from freelists. */
|
|
outer_end = isolate_freepages_range(&cc, outer_start, end);
|
|
if (!outer_end) {
|
|
ret = -EBUSY;
|
|
goto done;
|
|
}
|
|
|
|
/* Free head and tail (if any) */
|
|
if (start != outer_start)
|
|
free_contig_range(outer_start, start - outer_start);
|
|
if (end != outer_end)
|
|
free_contig_range(end, outer_end - end);
|
|
|
|
done:
|
|
undo_isolate_page_range(pfn_max_align_down(start),
|
|
pfn_max_align_up(end), migratetype);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(alloc_contig_range);
|
|
|
|
static int __alloc_contig_pages(unsigned long start_pfn,
|
|
unsigned long nr_pages, gfp_t gfp_mask)
|
|
{
|
|
unsigned long end_pfn = start_pfn + nr_pages;
|
|
|
|
return alloc_contig_range(start_pfn, end_pfn, MIGRATE_MOVABLE,
|
|
gfp_mask);
|
|
}
|
|
|
|
static bool pfn_range_valid_contig(struct zone *z, unsigned long start_pfn,
|
|
unsigned long nr_pages)
|
|
{
|
|
unsigned long i, end_pfn = start_pfn + nr_pages;
|
|
struct page *page;
|
|
|
|
for (i = start_pfn; i < end_pfn; i++) {
|
|
page = pfn_to_online_page(i);
|
|
if (!page)
|
|
return false;
|
|
|
|
if (page_zone(page) != z)
|
|
return false;
|
|
|
|
if (PageReserved(page))
|
|
return false;
|
|
|
|
if (page_count(page) > 0)
|
|
return false;
|
|
|
|
if (PageHuge(page))
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
static bool zone_spans_last_pfn(const struct zone *zone,
|
|
unsigned long start_pfn, unsigned long nr_pages)
|
|
{
|
|
unsigned long last_pfn = start_pfn + nr_pages - 1;
|
|
|
|
return zone_spans_pfn(zone, last_pfn);
|
|
}
|
|
|
|
/**
|
|
* alloc_contig_pages() -- tries to find and allocate contiguous range of pages
|
|
* @nr_pages: Number of contiguous pages to allocate
|
|
* @gfp_mask: GFP mask to limit search and used during compaction
|
|
* @nid: Target node
|
|
* @nodemask: Mask for other possible nodes
|
|
*
|
|
* This routine is a wrapper around alloc_contig_range(). It scans over zones
|
|
* on an applicable zonelist to find a contiguous pfn range which can then be
|
|
* tried for allocation with alloc_contig_range(). This routine is intended
|
|
* for allocation requests which can not be fulfilled with the buddy allocator.
|
|
*
|
|
* The allocated memory is always aligned to a page boundary. If nr_pages is a
|
|
* power of two then the alignment is guaranteed to be to the given nr_pages
|
|
* (e.g. 1GB request would be aligned to 1GB).
|
|
*
|
|
* Allocated pages can be freed with free_contig_range() or by manually calling
|
|
* __free_page() on each allocated page.
|
|
*
|
|
* Return: pointer to contiguous pages on success, or NULL if not successful.
|
|
*/
|
|
struct page *alloc_contig_pages(unsigned long nr_pages, gfp_t gfp_mask,
|
|
int nid, nodemask_t *nodemask)
|
|
{
|
|
unsigned long ret, pfn, flags;
|
|
struct zonelist *zonelist;
|
|
struct zone *zone;
|
|
struct zoneref *z;
|
|
|
|
zonelist = node_zonelist(nid, gfp_mask);
|
|
for_each_zone_zonelist_nodemask(zone, z, zonelist,
|
|
gfp_zone(gfp_mask), nodemask) {
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
|
|
pfn = ALIGN(zone->zone_start_pfn, nr_pages);
|
|
while (zone_spans_last_pfn(zone, pfn, nr_pages)) {
|
|
if (pfn_range_valid_contig(zone, pfn, nr_pages)) {
|
|
/*
|
|
* We release the zone lock here because
|
|
* alloc_contig_range() will also lock the zone
|
|
* at some point. If there's an allocation
|
|
* spinning on this lock, it may win the race
|
|
* and cause alloc_contig_range() to fail...
|
|
*/
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
ret = __alloc_contig_pages(pfn, nr_pages,
|
|
gfp_mask);
|
|
if (!ret)
|
|
return pfn_to_page(pfn);
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
}
|
|
pfn += nr_pages;
|
|
}
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
}
|
|
return NULL;
|
|
}
|
|
#endif /* CONFIG_CONTIG_ALLOC */
|
|
|
|
void free_contig_range(unsigned long pfn, unsigned int nr_pages)
|
|
{
|
|
unsigned int count = 0;
|
|
|
|
for (; nr_pages--; pfn++) {
|
|
struct page *page = pfn_to_page(pfn);
|
|
|
|
count += page_count(page) != 1;
|
|
__free_page(page);
|
|
}
|
|
WARN(count != 0, "%d pages are still in use!\n", count);
|
|
}
|
|
EXPORT_SYMBOL(free_contig_range);
|
|
|
|
/*
|
|
* The zone indicated has a new number of managed_pages; batch sizes and percpu
|
|
* page high values need to be recalulated.
|
|
*/
|
|
void __meminit zone_pcp_update(struct zone *zone)
|
|
{
|
|
mutex_lock(&pcp_batch_high_lock);
|
|
zone_set_pageset_high_and_batch(zone);
|
|
mutex_unlock(&pcp_batch_high_lock);
|
|
}
|
|
|
|
/*
|
|
* Effectively disable pcplists for the zone by setting the high limit to 0
|
|
* and draining all cpus. A concurrent page freeing on another CPU that's about
|
|
* to put the page on pcplist will either finish before the drain and the page
|
|
* will be drained, or observe the new high limit and skip the pcplist.
|
|
*
|
|
* Must be paired with a call to zone_pcp_enable().
|
|
*/
|
|
void zone_pcp_disable(struct zone *zone)
|
|
{
|
|
mutex_lock(&pcp_batch_high_lock);
|
|
__zone_set_pageset_high_and_batch(zone, 0, 1);
|
|
__drain_all_pages(zone, true);
|
|
}
|
|
|
|
void zone_pcp_enable(struct zone *zone)
|
|
{
|
|
__zone_set_pageset_high_and_batch(zone, zone->pageset_high, zone->pageset_batch);
|
|
mutex_unlock(&pcp_batch_high_lock);
|
|
}
|
|
|
|
void zone_pcp_reset(struct zone *zone)
|
|
{
|
|
unsigned long flags;
|
|
int cpu;
|
|
struct per_cpu_pageset *pset;
|
|
|
|
/* avoid races with drain_pages() */
|
|
local_irq_save(flags);
|
|
if (zone->pageset != &boot_pageset) {
|
|
for_each_online_cpu(cpu) {
|
|
pset = per_cpu_ptr(zone->pageset, cpu);
|
|
drain_zonestat(zone, pset);
|
|
}
|
|
free_percpu(zone->pageset);
|
|
zone->pageset = &boot_pageset;
|
|
}
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
#ifdef CONFIG_MEMORY_HOTREMOVE
|
|
/*
|
|
* All pages in the range must be in a single zone, must not contain holes,
|
|
* must span full sections, and must be isolated before calling this function.
|
|
*/
|
|
void __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
|
|
{
|
|
unsigned long pfn = start_pfn;
|
|
struct page *page;
|
|
struct zone *zone;
|
|
unsigned int order;
|
|
unsigned long flags;
|
|
|
|
offline_mem_sections(pfn, end_pfn);
|
|
zone = page_zone(pfn_to_page(pfn));
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
while (pfn < end_pfn) {
|
|
page = pfn_to_page(pfn);
|
|
/*
|
|
* The HWPoisoned page may be not in buddy system, and
|
|
* page_count() is not 0.
|
|
*/
|
|
if (unlikely(!PageBuddy(page) && PageHWPoison(page))) {
|
|
pfn++;
|
|
continue;
|
|
}
|
|
/*
|
|
* At this point all remaining PageOffline() pages have a
|
|
* reference count of 0 and can simply be skipped.
|
|
*/
|
|
if (PageOffline(page)) {
|
|
BUG_ON(page_count(page));
|
|
BUG_ON(PageBuddy(page));
|
|
pfn++;
|
|
continue;
|
|
}
|
|
|
|
BUG_ON(page_count(page));
|
|
BUG_ON(!PageBuddy(page));
|
|
order = buddy_order(page);
|
|
del_page_from_free_list(page, zone, order);
|
|
pfn += (1 << order);
|
|
}
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
}
|
|
#endif
|
|
|
|
bool is_free_buddy_page(struct page *page)
|
|
{
|
|
struct zone *zone = page_zone(page);
|
|
unsigned long pfn = page_to_pfn(page);
|
|
unsigned long flags;
|
|
unsigned int order;
|
|
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
for (order = 0; order < MAX_ORDER; order++) {
|
|
struct page *page_head = page - (pfn & ((1 << order) - 1));
|
|
|
|
if (PageBuddy(page_head) && buddy_order(page_head) >= order)
|
|
break;
|
|
}
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
|
|
return order < MAX_ORDER;
|
|
}
|
|
|
|
#ifdef CONFIG_MEMORY_FAILURE
|
|
/*
|
|
* Break down a higher-order page in sub-pages, and keep our target out of
|
|
* buddy allocator.
|
|
*/
|
|
static void break_down_buddy_pages(struct zone *zone, struct page *page,
|
|
struct page *target, int low, int high,
|
|
int migratetype)
|
|
{
|
|
unsigned long size = 1 << high;
|
|
struct page *current_buddy, *next_page;
|
|
|
|
while (high > low) {
|
|
high--;
|
|
size >>= 1;
|
|
|
|
if (target >= &page[size]) {
|
|
next_page = page + size;
|
|
current_buddy = page;
|
|
} else {
|
|
next_page = page;
|
|
current_buddy = page + size;
|
|
}
|
|
|
|
if (set_page_guard(zone, current_buddy, high, migratetype))
|
|
continue;
|
|
|
|
if (current_buddy != target) {
|
|
add_to_free_list(current_buddy, zone, high, migratetype);
|
|
set_buddy_order(current_buddy, high);
|
|
page = next_page;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Take a page that will be marked as poisoned off the buddy allocator.
|
|
*/
|
|
bool take_page_off_buddy(struct page *page)
|
|
{
|
|
struct zone *zone = page_zone(page);
|
|
unsigned long pfn = page_to_pfn(page);
|
|
unsigned long flags;
|
|
unsigned int order;
|
|
bool ret = false;
|
|
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
for (order = 0; order < MAX_ORDER; order++) {
|
|
struct page *page_head = page - (pfn & ((1 << order) - 1));
|
|
int page_order = buddy_order(page_head);
|
|
|
|
if (PageBuddy(page_head) && page_order >= order) {
|
|
unsigned long pfn_head = page_to_pfn(page_head);
|
|
int migratetype = get_pfnblock_migratetype(page_head,
|
|
pfn_head);
|
|
|
|
del_page_from_free_list(page_head, zone, page_order);
|
|
break_down_buddy_pages(zone, page_head, page, 0,
|
|
page_order, migratetype);
|
|
ret = true;
|
|
break;
|
|
}
|
|
if (page_count(page_head) > 0)
|
|
break;
|
|
}
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
return ret;
|
|
}
|
|
#endif
|