6044 строки
167 KiB
C
6044 строки
167 KiB
C
/*
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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/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/bootmem.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/kmemcheck.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/notifier.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/stop_machine.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/page_cgroup.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 <linux/ftrace_event.h>
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#include <linux/memcontrol.h>
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#include <linux/prefetch.h>
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#include <linux/migrate.h>
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#include <linux/page-debug-flags.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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#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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#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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/*
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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_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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unsigned long totalram_pages __read_mostly;
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unsigned long totalreserve_pages __read_mostly;
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/*
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* When calculating the number of globally allowed dirty pages, there
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* is a certain number of per-zone reserves that should not be
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* considered dirtyable memory. This is the sum of those reserves
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* over all existing zones that contribute dirtyable memory.
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*/
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unsigned long dirty_balance_reserve __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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#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 pm_mutex held (gfp_allowed_mask also should
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* only be modified with pm_mutex held, unless the suspend/hibernate code is
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* guaranteed not to run in parallel 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(&pm_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(&pm_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_IOFS;
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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_IOFS) == GFP_IOFS)
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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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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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/*
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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 (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-1] = {
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#ifdef CONFIG_ZONE_DMA
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256,
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#endif
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#ifdef CONFIG_ZONE_DMA32
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256,
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#endif
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#ifdef CONFIG_HIGHMEM
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32,
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#endif
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32,
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};
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EXPORT_SYMBOL(totalram_pages);
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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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};
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int min_free_kbytes = 1024;
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static unsigned long __meminitdata nr_kernel_pages;
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static unsigned long __meminitdata nr_all_pages;
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static unsigned long __meminitdata dma_reserve;
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#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
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static unsigned long __meminitdata arch_zone_lowest_possible_pfn[MAX_NR_ZONES];
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static unsigned long __meminitdata arch_zone_highest_possible_pfn[MAX_NR_ZONES];
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static unsigned long __initdata required_kernelcore;
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static unsigned long __initdata required_movablecore;
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static unsigned long __meminitdata zone_movable_pfn[MAX_NUMNODES];
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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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#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
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#if MAX_NUMNODES > 1
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int nr_node_ids __read_mostly = MAX_NUMNODES;
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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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/*
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* NOTE:
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* Don't use set_pageblock_migratetype(page, MIGRATE_ISOLATE) directly.
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* Instead, use {un}set_pageblock_isolate.
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*/
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void set_pageblock_migratetype(struct page *page, int migratetype)
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{
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if (unlikely(page_group_by_mobility_disabled))
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migratetype = MIGRATE_UNMOVABLE;
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set_pageblock_flags_group(page, (unsigned long)migratetype,
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PB_migrate, PB_migrate_end);
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}
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bool oom_killer_disabled __read_mostly;
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#ifdef CONFIG_DEBUG_VM
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static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
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{
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int ret = 0;
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unsigned seq;
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unsigned long pfn = page_to_pfn(page);
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do {
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seq = zone_span_seqbegin(zone);
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if (pfn >= zone->zone_start_pfn + zone->spanned_pages)
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ret = 1;
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else if (pfn < zone->zone_start_pfn)
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ret = 1;
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} while (zone_span_seqretry(zone, seq));
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return ret;
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}
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static int page_is_consistent(struct zone *zone, struct page *page)
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{
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if (!pfn_valid_within(page_to_pfn(page)))
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return 0;
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if (zone != page_zone(page))
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return 0;
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return 1;
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}
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/*
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* Temporary debugging check for pages not lying within a given zone.
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*/
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static int bad_range(struct zone *zone, struct page *page)
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{
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if (page_outside_zone_boundaries(zone, page))
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return 1;
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if (!page_is_consistent(zone, page))
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return 1;
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return 0;
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}
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#else
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static inline int bad_range(struct zone *zone, struct page *page)
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{
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return 0;
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}
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#endif
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static void bad_page(struct page *page)
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{
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static unsigned long resume;
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static unsigned long nr_shown;
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static unsigned long nr_unshown;
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/* Don't complain about poisoned pages */
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if (PageHWPoison(page)) {
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reset_page_mapcount(page); /* remove PageBuddy */
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return;
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}
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/*
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* Allow a burst of 60 reports, then keep quiet for that minute;
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* or allow a steady drip of one report per second.
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*/
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if (nr_shown == 60) {
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if (time_before(jiffies, resume)) {
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nr_unshown++;
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goto out;
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}
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if (nr_unshown) {
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printk(KERN_ALERT
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"BUG: Bad page state: %lu messages suppressed\n",
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nr_unshown);
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nr_unshown = 0;
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}
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nr_shown = 0;
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}
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if (nr_shown++ == 0)
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resume = jiffies + 60 * HZ;
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printk(KERN_ALERT "BUG: Bad page state in process %s pfn:%05lx\n",
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current->comm, page_to_pfn(page));
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dump_page(page);
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print_modules();
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dump_stack();
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out:
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/* Leave bad fields for debug, except PageBuddy could make trouble */
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reset_page_mapcount(page); /* remove PageBuddy */
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add_taint(TAINT_BAD_PAGE);
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}
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/*
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* Higher-order pages are called "compound pages". They are structured thusly:
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*
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* The first PAGE_SIZE page is called the "head page".
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*
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* The remaining PAGE_SIZE pages are called "tail pages".
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*
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* All pages have PG_compound set. All tail pages have their ->first_page
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* pointing at the head page.
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*
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* The first tail page's ->lru.next holds the address of the compound page's
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* put_page() function. Its ->lru.prev holds the order of allocation.
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* This usage means that zero-order pages may not be compound.
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*/
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static void free_compound_page(struct page *page)
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{
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__free_pages_ok(page, compound_order(page));
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}
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void prep_compound_page(struct page *page, unsigned long order)
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{
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int i;
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int nr_pages = 1 << order;
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set_compound_page_dtor(page, free_compound_page);
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set_compound_order(page, order);
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__SetPageHead(page);
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for (i = 1; i < nr_pages; i++) {
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struct page *p = page + i;
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__SetPageTail(p);
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set_page_count(p, 0);
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p->first_page = page;
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}
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}
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/* update __split_huge_page_refcount if you change this function */
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static int destroy_compound_page(struct page *page, unsigned long order)
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{
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int i;
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int nr_pages = 1 << order;
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int bad = 0;
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if (unlikely(compound_order(page) != order) ||
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unlikely(!PageHead(page))) {
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bad_page(page);
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bad++;
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}
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__ClearPageHead(page);
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for (i = 1; i < nr_pages; i++) {
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struct page *p = page + i;
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if (unlikely(!PageTail(p) || (p->first_page != page))) {
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bad_page(page);
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bad++;
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}
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__ClearPageTail(p);
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}
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return bad;
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}
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static inline void prep_zero_page(struct page *page, int order, gfp_t gfp_flags)
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{
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int i;
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/*
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* clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
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* and __GFP_HIGHMEM from hard or soft interrupt context.
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*/
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VM_BUG_ON((gfp_flags & __GFP_HIGHMEM) && in_interrupt());
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for (i = 0; i < (1 << order); i++)
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clear_highpage(page + i);
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}
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#ifdef CONFIG_DEBUG_PAGEALLOC
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unsigned int _debug_guardpage_minorder;
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static int __init debug_guardpage_minorder_setup(char *buf)
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{
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unsigned long res;
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if (kstrtoul(buf, 10, &res) < 0 || res > MAX_ORDER / 2) {
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printk(KERN_ERR "Bad debug_guardpage_minorder value\n");
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return 0;
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}
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_debug_guardpage_minorder = res;
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printk(KERN_INFO "Setting debug_guardpage_minorder to %lu\n", res);
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return 0;
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}
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__setup("debug_guardpage_minorder=", debug_guardpage_minorder_setup);
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static inline void set_page_guard_flag(struct page *page)
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{
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__set_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags);
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}
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static inline void clear_page_guard_flag(struct page *page)
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{
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__clear_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags);
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}
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#else
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static inline void set_page_guard_flag(struct page *page) { }
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static inline void clear_page_guard_flag(struct page *page) { }
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#endif
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static inline void set_page_order(struct page *page, int order)
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{
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set_page_private(page, order);
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__SetPageBuddy(page);
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}
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static inline void rmv_page_order(struct page *page)
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{
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__ClearPageBuddy(page);
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set_page_private(page, 0);
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}
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/*
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* Locate the struct page for both the matching buddy in our
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* pair (buddy1) and the combined O(n+1) page they form (page).
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*
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* 1) Any buddy B1 will have an order O twin B2 which satisfies
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* the following equation:
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* B2 = B1 ^ (1 << O)
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* For example, if the starting buddy (buddy2) is #8 its order
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* 1 buddy is #10:
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* B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
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*
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* 2) Any buddy B will have an order O+1 parent P which
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* satisfies the following equation:
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* P = B & ~(1 << O)
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*
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* Assumption: *_mem_map is contiguous at least up to MAX_ORDER
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*/
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static inline unsigned long
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__find_buddy_index(unsigned long page_idx, unsigned int order)
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{
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return page_idx ^ (1 << order);
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}
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/*
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* This function checks whether a page is free && is the buddy
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* we can do coalesce a page and its buddy if
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* (a) the buddy is not in a hole &&
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* (b) the buddy is in the buddy system &&
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* (c) a page and its buddy have the same order &&
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* (d) a page and its buddy are in the same zone.
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*
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* For recording whether a page is in the buddy system, we set ->_mapcount -2.
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* Setting, clearing, and testing _mapcount -2 is serialized by zone->lock.
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*
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* For recording page's order, we use page_private(page).
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*/
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static inline int page_is_buddy(struct page *page, struct page *buddy,
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int order)
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{
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if (!pfn_valid_within(page_to_pfn(buddy)))
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return 0;
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|
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if (page_zone_id(page) != page_zone_id(buddy))
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return 0;
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|
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if (page_is_guard(buddy) && page_order(buddy) == order) {
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VM_BUG_ON(page_count(buddy) != 0);
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return 1;
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}
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|
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if (PageBuddy(buddy) && page_order(buddy) == order) {
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VM_BUG_ON(page_count(buddy) != 0);
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return 1;
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}
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return 0;
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}
|
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|
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/*
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* Freeing function for a buddy system allocator.
|
|
*
|
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* The concept of a buddy system is to maintain direct-mapped table
|
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* (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 _mapcount -2. 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.
|
|
*
|
|
* -- wli
|
|
*/
|
|
|
|
static inline void __free_one_page(struct page *page,
|
|
struct zone *zone, unsigned int order,
|
|
int migratetype)
|
|
{
|
|
unsigned long page_idx;
|
|
unsigned long combined_idx;
|
|
unsigned long uninitialized_var(buddy_idx);
|
|
struct page *buddy;
|
|
|
|
if (unlikely(PageCompound(page)))
|
|
if (unlikely(destroy_compound_page(page, order)))
|
|
return;
|
|
|
|
VM_BUG_ON(migratetype == -1);
|
|
|
|
page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1);
|
|
|
|
VM_BUG_ON(page_idx & ((1 << order) - 1));
|
|
VM_BUG_ON(bad_range(zone, page));
|
|
|
|
while (order < MAX_ORDER-1) {
|
|
buddy_idx = __find_buddy_index(page_idx, order);
|
|
buddy = page + (buddy_idx - page_idx);
|
|
if (!page_is_buddy(page, buddy, order))
|
|
break;
|
|
/*
|
|
* 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_flag(buddy);
|
|
set_page_private(page, 0);
|
|
__mod_zone_page_state(zone, NR_FREE_PAGES, 1 << order);
|
|
} else {
|
|
list_del(&buddy->lru);
|
|
zone->free_area[order].nr_free--;
|
|
rmv_page_order(buddy);
|
|
}
|
|
combined_idx = buddy_idx & page_idx;
|
|
page = page + (combined_idx - page_idx);
|
|
page_idx = combined_idx;
|
|
order++;
|
|
}
|
|
set_page_order(page, order);
|
|
|
|
/*
|
|
* 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
|
|
*/
|
|
if ((order < MAX_ORDER-2) && pfn_valid_within(page_to_pfn(buddy))) {
|
|
struct page *higher_page, *higher_buddy;
|
|
combined_idx = buddy_idx & page_idx;
|
|
higher_page = page + (combined_idx - page_idx);
|
|
buddy_idx = __find_buddy_index(combined_idx, order + 1);
|
|
higher_buddy = page + (buddy_idx - combined_idx);
|
|
if (page_is_buddy(higher_page, higher_buddy, order + 1)) {
|
|
list_add_tail(&page->lru,
|
|
&zone->free_area[order].free_list[migratetype]);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
list_add(&page->lru, &zone->free_area[order].free_list[migratetype]);
|
|
out:
|
|
zone->free_area[order].nr_free++;
|
|
}
|
|
|
|
/*
|
|
* free_page_mlock() -- clean up attempts to free and mlocked() page.
|
|
* Page should not be on lru, so no need to fix that up.
|
|
* free_pages_check() will verify...
|
|
*/
|
|
static inline void free_page_mlock(struct page *page)
|
|
{
|
|
__dec_zone_page_state(page, NR_MLOCK);
|
|
__count_vm_event(UNEVICTABLE_MLOCKFREED);
|
|
}
|
|
|
|
static inline int free_pages_check(struct page *page)
|
|
{
|
|
if (unlikely(page_mapcount(page) |
|
|
(page->mapping != NULL) |
|
|
(atomic_read(&page->_count) != 0) |
|
|
(page->flags & PAGE_FLAGS_CHECK_AT_FREE) |
|
|
(mem_cgroup_bad_page_check(page)))) {
|
|
bad_page(page);
|
|
return 1;
|
|
}
|
|
if (page->flags & PAGE_FLAGS_CHECK_AT_PREP)
|
|
page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* 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 to_free = count;
|
|
|
|
spin_lock(&zone->lock);
|
|
zone->all_unreclaimable = 0;
|
|
zone->pages_scanned = 0;
|
|
|
|
while (to_free) {
|
|
struct page *page;
|
|
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 = to_free;
|
|
|
|
do {
|
|
page = list_entry(list->prev, struct page, lru);
|
|
/* must delete as __free_one_page list manipulates */
|
|
list_del(&page->lru);
|
|
/* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */
|
|
__free_one_page(page, zone, 0, page_private(page));
|
|
trace_mm_page_pcpu_drain(page, 0, page_private(page));
|
|
} while (--to_free && --batch_free && !list_empty(list));
|
|
}
|
|
__mod_zone_page_state(zone, NR_FREE_PAGES, count);
|
|
spin_unlock(&zone->lock);
|
|
}
|
|
|
|
static void free_one_page(struct zone *zone, struct page *page, int order,
|
|
int migratetype)
|
|
{
|
|
spin_lock(&zone->lock);
|
|
zone->all_unreclaimable = 0;
|
|
zone->pages_scanned = 0;
|
|
|
|
__free_one_page(page, zone, order, migratetype);
|
|
__mod_zone_page_state(zone, NR_FREE_PAGES, 1 << order);
|
|
spin_unlock(&zone->lock);
|
|
}
|
|
|
|
static bool free_pages_prepare(struct page *page, unsigned int order)
|
|
{
|
|
int i;
|
|
int bad = 0;
|
|
|
|
trace_mm_page_free(page, order);
|
|
kmemcheck_free_shadow(page, order);
|
|
|
|
if (PageAnon(page))
|
|
page->mapping = NULL;
|
|
for (i = 0; i < (1 << order); i++)
|
|
bad += free_pages_check(page + i);
|
|
if (bad)
|
|
return false;
|
|
|
|
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);
|
|
}
|
|
arch_free_page(page, order);
|
|
kernel_map_pages(page, 1 << order, 0);
|
|
|
|
return true;
|
|
}
|
|
|
|
static void __free_pages_ok(struct page *page, unsigned int order)
|
|
{
|
|
unsigned long flags;
|
|
int wasMlocked = __TestClearPageMlocked(page);
|
|
|
|
if (!free_pages_prepare(page, order))
|
|
return;
|
|
|
|
local_irq_save(flags);
|
|
if (unlikely(wasMlocked))
|
|
free_page_mlock(page);
|
|
__count_vm_events(PGFREE, 1 << order);
|
|
free_one_page(page_zone(page), page, order,
|
|
get_pageblock_migratetype(page));
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
void __meminit __free_pages_bootmem(struct page *page, unsigned int order)
|
|
{
|
|
unsigned int nr_pages = 1 << order;
|
|
unsigned int loop;
|
|
|
|
prefetchw(page);
|
|
for (loop = 0; loop < nr_pages; loop++) {
|
|
struct page *p = &page[loop];
|
|
|
|
if (loop + 1 < nr_pages)
|
|
prefetchw(p + 1);
|
|
__ClearPageReserved(p);
|
|
set_page_count(p, 0);
|
|
}
|
|
|
|
set_page_refcounted(page);
|
|
__free_pages(page, order);
|
|
}
|
|
|
|
#ifdef CONFIG_CMA
|
|
/* Free whole pageblock and set it's 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_page_refcounted(page);
|
|
set_pageblock_migratetype(page, MIGRATE_CMA);
|
|
__free_pages(page, pageblock_order);
|
|
totalram_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.
|
|
*
|
|
* -- wli
|
|
*/
|
|
static inline void expand(struct zone *zone, struct page *page,
|
|
int low, int high, struct free_area *area,
|
|
int migratetype)
|
|
{
|
|
unsigned long size = 1 << high;
|
|
|
|
while (high > low) {
|
|
area--;
|
|
high--;
|
|
size >>= 1;
|
|
VM_BUG_ON(bad_range(zone, &page[size]));
|
|
|
|
#ifdef CONFIG_DEBUG_PAGEALLOC
|
|
if (high < debug_guardpage_minorder()) {
|
|
/*
|
|
* 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
|
|
*/
|
|
INIT_LIST_HEAD(&page[size].lru);
|
|
set_page_guard_flag(&page[size]);
|
|
set_page_private(&page[size], high);
|
|
/* Guard pages are not available for any usage */
|
|
__mod_zone_page_state(zone, NR_FREE_PAGES, -(1 << high));
|
|
continue;
|
|
}
|
|
#endif
|
|
list_add(&page[size].lru, &area->free_list[migratetype]);
|
|
area->nr_free++;
|
|
set_page_order(&page[size], high);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This page is about to be returned from the page allocator
|
|
*/
|
|
static inline int check_new_page(struct page *page)
|
|
{
|
|
if (unlikely(page_mapcount(page) |
|
|
(page->mapping != NULL) |
|
|
(atomic_read(&page->_count) != 0) |
|
|
(page->flags & PAGE_FLAGS_CHECK_AT_PREP) |
|
|
(mem_cgroup_bad_page_check(page)))) {
|
|
bad_page(page);
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int prep_new_page(struct page *page, int order, gfp_t gfp_flags)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < (1 << order); i++) {
|
|
struct page *p = page + i;
|
|
if (unlikely(check_new_page(p)))
|
|
return 1;
|
|
}
|
|
|
|
set_page_private(page, 0);
|
|
set_page_refcounted(page);
|
|
|
|
arch_alloc_page(page, order);
|
|
kernel_map_pages(page, 1 << order, 1);
|
|
|
|
if (gfp_flags & __GFP_ZERO)
|
|
prep_zero_page(page, order, gfp_flags);
|
|
|
|
if (order && (gfp_flags & __GFP_COMP))
|
|
prep_compound_page(page, order);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Go through the free lists for the given migratetype and remove
|
|
* the smallest available page from the freelists
|
|
*/
|
|
static 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]);
|
|
if (list_empty(&area->free_list[migratetype]))
|
|
continue;
|
|
|
|
page = list_entry(area->free_list[migratetype].next,
|
|
struct page, lru);
|
|
list_del(&page->lru);
|
|
rmv_page_order(page);
|
|
area->nr_free--;
|
|
expand(zone, page, order, current_order, area, 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][4] = {
|
|
[MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
|
|
[MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
|
|
#ifdef CONFIG_CMA
|
|
[MIGRATE_MOVABLE] = { MIGRATE_CMA, MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
|
|
[MIGRATE_CMA] = { MIGRATE_RESERVE }, /* Never used */
|
|
#else
|
|
[MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
|
|
#endif
|
|
[MIGRATE_RESERVE] = { MIGRATE_RESERVE }, /* Never used */
|
|
[MIGRATE_ISOLATE] = { MIGRATE_RESERVE }, /* Never used */
|
|
};
|
|
|
|
/*
|
|
* Move the free pages in a range to the free lists 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)
|
|
{
|
|
struct page *page;
|
|
unsigned long order;
|
|
int pages_moved = 0;
|
|
|
|
#ifndef CONFIG_HOLES_IN_ZONE
|
|
/*
|
|
* page_zone is not safe to call in this context when
|
|
* CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
|
|
* anyway as we check zone boundaries in move_freepages_block().
|
|
* Remove at a later date when no bug reports exist related to
|
|
* grouping pages by mobility
|
|
*/
|
|
BUG_ON(page_zone(start_page) != page_zone(end_page));
|
|
#endif
|
|
|
|
for (page = start_page; page <= end_page;) {
|
|
/* Make sure we are not inadvertently changing nodes */
|
|
VM_BUG_ON(page_to_nid(page) != zone_to_nid(zone));
|
|
|
|
if (!pfn_valid_within(page_to_pfn(page))) {
|
|
page++;
|
|
continue;
|
|
}
|
|
|
|
if (!PageBuddy(page)) {
|
|
page++;
|
|
continue;
|
|
}
|
|
|
|
order = page_order(page);
|
|
list_move(&page->lru,
|
|
&zone->free_area[order].free_list[migratetype]);
|
|
page += 1 << order;
|
|
pages_moved += 1 << order;
|
|
}
|
|
|
|
return pages_moved;
|
|
}
|
|
|
|
int move_freepages_block(struct zone *zone, struct page *page,
|
|
int migratetype)
|
|
{
|
|
unsigned long start_pfn, end_pfn;
|
|
struct page *start_page, *end_page;
|
|
|
|
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 (start_pfn < zone->zone_start_pfn)
|
|
start_page = page;
|
|
if (end_pfn >= zone->zone_start_pfn + zone->spanned_pages)
|
|
return 0;
|
|
|
|
return move_freepages(zone, start_page, end_page, migratetype);
|
|
}
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
/* Remove an element from the buddy allocator from the fallback list */
|
|
static inline struct page *
|
|
__rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
|
|
{
|
|
struct free_area * area;
|
|
int current_order;
|
|
struct page *page;
|
|
int migratetype, i;
|
|
|
|
/* Find the largest possible block of pages in the other list */
|
|
for (current_order = MAX_ORDER-1; current_order >= order;
|
|
--current_order) {
|
|
for (i = 0;; i++) {
|
|
migratetype = fallbacks[start_migratetype][i];
|
|
|
|
/* MIGRATE_RESERVE handled later if necessary */
|
|
if (migratetype == MIGRATE_RESERVE)
|
|
break;
|
|
|
|
area = &(zone->free_area[current_order]);
|
|
if (list_empty(&area->free_list[migratetype]))
|
|
continue;
|
|
|
|
page = list_entry(area->free_list[migratetype].next,
|
|
struct page, lru);
|
|
area->nr_free--;
|
|
|
|
/*
|
|
* If breaking a large block of pages, move all free
|
|
* pages to the preferred allocation list. If falling
|
|
* back for a reclaimable kernel allocation, be more
|
|
* aggressive about taking ownership of free pages
|
|
*
|
|
* On the other hand, never change migration
|
|
* type of MIGRATE_CMA pageblocks nor move CMA
|
|
* pages on different free lists. We don't
|
|
* want unmovable pages to be allocated from
|
|
* MIGRATE_CMA areas.
|
|
*/
|
|
if (!is_migrate_cma(migratetype) &&
|
|
(unlikely(current_order >= pageblock_order / 2) ||
|
|
start_migratetype == MIGRATE_RECLAIMABLE ||
|
|
page_group_by_mobility_disabled)) {
|
|
int pages;
|
|
pages = move_freepages_block(zone, page,
|
|
start_migratetype);
|
|
|
|
/* Claim the whole block if over half of it is free */
|
|
if (pages >= (1 << (pageblock_order-1)) ||
|
|
page_group_by_mobility_disabled)
|
|
set_pageblock_migratetype(page,
|
|
start_migratetype);
|
|
|
|
migratetype = start_migratetype;
|
|
}
|
|
|
|
/* Remove the page from the freelists */
|
|
list_del(&page->lru);
|
|
rmv_page_order(page);
|
|
|
|
/* Take ownership for orders >= pageblock_order */
|
|
if (current_order >= pageblock_order &&
|
|
!is_migrate_cma(migratetype))
|
|
change_pageblock_range(page, current_order,
|
|
start_migratetype);
|
|
|
|
expand(zone, page, order, current_order, area,
|
|
is_migrate_cma(migratetype)
|
|
? migratetype : start_migratetype);
|
|
|
|
trace_mm_page_alloc_extfrag(page, order, current_order,
|
|
start_migratetype, migratetype);
|
|
|
|
return page;
|
|
}
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Do the hard work of removing an element from the buddy allocator.
|
|
* Call me with the zone->lock already held.
|
|
*/
|
|
static struct page *__rmqueue(struct zone *zone, unsigned int order,
|
|
int migratetype)
|
|
{
|
|
struct page *page;
|
|
|
|
retry_reserve:
|
|
page = __rmqueue_smallest(zone, order, migratetype);
|
|
|
|
if (unlikely(!page) && migratetype != MIGRATE_RESERVE) {
|
|
page = __rmqueue_fallback(zone, order, migratetype);
|
|
|
|
/*
|
|
* Use MIGRATE_RESERVE rather than fail an allocation. goto
|
|
* is used because __rmqueue_smallest is an inline function
|
|
* and we want just one call site
|
|
*/
|
|
if (!page) {
|
|
migratetype = MIGRATE_RESERVE;
|
|
goto retry_reserve;
|
|
}
|
|
}
|
|
|
|
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, int cold)
|
|
{
|
|
int mt = migratetype, i;
|
|
|
|
spin_lock(&zone->lock);
|
|
for (i = 0; i < count; ++i) {
|
|
struct page *page = __rmqueue(zone, order, migratetype);
|
|
if (unlikely(page == NULL))
|
|
break;
|
|
|
|
/*
|
|
* Split buddy pages returned by expand() are received here
|
|
* in physical page order. The page is added to the callers and
|
|
* list and the list head then moves forward. From the callers
|
|
* perspective, the linked list is ordered by page number in
|
|
* some conditions. This is useful for IO devices that can
|
|
* merge IO requests if the physical pages are ordered
|
|
* properly.
|
|
*/
|
|
if (likely(cold == 0))
|
|
list_add(&page->lru, list);
|
|
else
|
|
list_add_tail(&page->lru, list);
|
|
if (IS_ENABLED(CONFIG_CMA)) {
|
|
mt = get_pageblock_migratetype(page);
|
|
if (!is_migrate_cma(mt) && mt != MIGRATE_ISOLATE)
|
|
mt = migratetype;
|
|
}
|
|
set_page_private(page, mt);
|
|
list = &page->lru;
|
|
}
|
|
__mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
|
|
spin_unlock(&zone->lock);
|
|
return i;
|
|
}
|
|
|
|
#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;
|
|
|
|
local_irq_save(flags);
|
|
if (pcp->count >= pcp->batch)
|
|
to_drain = pcp->batch;
|
|
else
|
|
to_drain = pcp->count;
|
|
if (to_drain > 0) {
|
|
free_pcppages_bulk(zone, to_drain, pcp);
|
|
pcp->count -= to_drain;
|
|
}
|
|
local_irq_restore(flags);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Drain pages of 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)
|
|
{
|
|
unsigned long flags;
|
|
struct zone *zone;
|
|
|
|
for_each_populated_zone(zone) {
|
|
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);
|
|
pcp->count = 0;
|
|
}
|
|
local_irq_restore(flags);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Spill all of this CPU's per-cpu pages back into the buddy allocator.
|
|
*/
|
|
void drain_local_pages(void *arg)
|
|
{
|
|
drain_pages(smp_processor_id());
|
|
}
|
|
|
|
/*
|
|
* Spill all the per-cpu pages from all CPUs back into the buddy allocator.
|
|
*
|
|
* Note that this code is protected against sending an IPI to an offline
|
|
* CPU but does not guarantee sending an IPI to newly hotplugged CPUs:
|
|
* on_each_cpu_mask() blocks hotplug and won't talk to offlined CPUs but
|
|
* nothing keeps CPUs from showing up after we populated the cpumask and
|
|
* before the call to on_each_cpu_mask().
|
|
*/
|
|
void drain_all_pages(void)
|
|
{
|
|
int cpu;
|
|
struct per_cpu_pageset *pcp;
|
|
struct zone *zone;
|
|
|
|
/*
|
|
* Allocate in the BSS so we wont require allocation in
|
|
* direct reclaim path for CONFIG_CPUMASK_OFFSTACK=y
|
|
*/
|
|
static cpumask_t cpus_with_pcps;
|
|
|
|
/*
|
|
* 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) {
|
|
bool has_pcps = false;
|
|
for_each_populated_zone(zone) {
|
|
pcp = per_cpu_ptr(zone->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);
|
|
}
|
|
on_each_cpu_mask(&cpus_with_pcps, drain_local_pages, NULL, 1);
|
|
}
|
|
|
|
#ifdef CONFIG_HIBERNATION
|
|
|
|
void mark_free_pages(struct zone *zone)
|
|
{
|
|
unsigned long pfn, max_zone_pfn;
|
|
unsigned long flags;
|
|
int order, t;
|
|
struct list_head *curr;
|
|
|
|
if (!zone->spanned_pages)
|
|
return;
|
|
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
|
|
max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
|
|
for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
|
|
if (pfn_valid(pfn)) {
|
|
struct page *page = pfn_to_page(pfn);
|
|
|
|
if (!swsusp_page_is_forbidden(page))
|
|
swsusp_unset_page_free(page);
|
|
}
|
|
|
|
for_each_migratetype_order(order, t) {
|
|
list_for_each(curr, &zone->free_area[order].free_list[t]) {
|
|
unsigned long i;
|
|
|
|
pfn = page_to_pfn(list_entry(curr, struct page, lru));
|
|
for (i = 0; i < (1UL << order); i++)
|
|
swsusp_set_page_free(pfn_to_page(pfn + i));
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
}
|
|
#endif /* CONFIG_PM */
|
|
|
|
/*
|
|
* Free a 0-order page
|
|
* cold == 1 ? free a cold page : free a hot page
|
|
*/
|
|
void free_hot_cold_page(struct page *page, int cold)
|
|
{
|
|
struct zone *zone = page_zone(page);
|
|
struct per_cpu_pages *pcp;
|
|
unsigned long flags;
|
|
int migratetype;
|
|
int wasMlocked = __TestClearPageMlocked(page);
|
|
|
|
if (!free_pages_prepare(page, 0))
|
|
return;
|
|
|
|
migratetype = get_pageblock_migratetype(page);
|
|
set_page_private(page, migratetype);
|
|
local_irq_save(flags);
|
|
if (unlikely(wasMlocked))
|
|
free_page_mlock(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 RESERVE 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(migratetype == MIGRATE_ISOLATE)) {
|
|
free_one_page(zone, page, 0, migratetype);
|
|
goto out;
|
|
}
|
|
migratetype = MIGRATE_MOVABLE;
|
|
}
|
|
|
|
pcp = &this_cpu_ptr(zone->pageset)->pcp;
|
|
if (cold)
|
|
list_add_tail(&page->lru, &pcp->lists[migratetype]);
|
|
else
|
|
list_add(&page->lru, &pcp->lists[migratetype]);
|
|
pcp->count++;
|
|
if (pcp->count >= pcp->high) {
|
|
free_pcppages_bulk(zone, pcp->batch, pcp);
|
|
pcp->count -= pcp->batch;
|
|
}
|
|
|
|
out:
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
/*
|
|
* Free a list of 0-order pages
|
|
*/
|
|
void free_hot_cold_page_list(struct list_head *list, int cold)
|
|
{
|
|
struct page *page, *next;
|
|
|
|
list_for_each_entry_safe(page, next, list, lru) {
|
|
trace_mm_page_free_batched(page, cold);
|
|
free_hot_cold_page(page, cold);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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(PageCompound(page));
|
|
VM_BUG_ON(!page_count(page));
|
|
|
|
#ifdef CONFIG_KMEMCHECK
|
|
/*
|
|
* Split shadow pages too, because free(page[0]) would
|
|
* otherwise free the whole shadow.
|
|
*/
|
|
if (kmemcheck_page_is_tracked(page))
|
|
split_page(virt_to_page(page[0].shadow), order);
|
|
#endif
|
|
|
|
for (i = 1; i < (1 << order); i++)
|
|
set_page_refcounted(page + i);
|
|
}
|
|
|
|
/*
|
|
* Similar to split_page except the page is already free. As this is only
|
|
* being used for migration, the migratetype of the block also changes.
|
|
* As this is called with interrupts disabled, the caller is responsible
|
|
* for calling arch_alloc_page() and kernel_map_page() after interrupts
|
|
* are enabled.
|
|
*
|
|
* Note: this is probably too low level an operation for use in drivers.
|
|
* Please consult with lkml before using this in your driver.
|
|
*/
|
|
int split_free_page(struct page *page)
|
|
{
|
|
unsigned int order;
|
|
unsigned long watermark;
|
|
struct zone *zone;
|
|
|
|
BUG_ON(!PageBuddy(page));
|
|
|
|
zone = page_zone(page);
|
|
order = page_order(page);
|
|
|
|
/* Obey watermarks as if the page was being allocated */
|
|
watermark = low_wmark_pages(zone) + (1 << order);
|
|
if (!zone_watermark_ok(zone, 0, watermark, 0, 0))
|
|
return 0;
|
|
|
|
/* Remove page from free list */
|
|
list_del(&page->lru);
|
|
zone->free_area[order].nr_free--;
|
|
rmv_page_order(page);
|
|
__mod_zone_page_state(zone, NR_FREE_PAGES, -(1UL << order));
|
|
|
|
/* Split into individual pages */
|
|
set_page_refcounted(page);
|
|
split_page(page, order);
|
|
|
|
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 (mt != MIGRATE_ISOLATE && !is_migrate_cma(mt))
|
|
set_pageblock_migratetype(page,
|
|
MIGRATE_MOVABLE);
|
|
}
|
|
}
|
|
|
|
return 1 << order;
|
|
}
|
|
|
|
/*
|
|
* Really, prep_compound_page() should be called from __rmqueue_bulk(). But
|
|
* we cheat by calling it from here, in the order > 0 path. Saves a branch
|
|
* or two.
|
|
*/
|
|
static inline
|
|
struct page *buffered_rmqueue(struct zone *preferred_zone,
|
|
struct zone *zone, int order, gfp_t gfp_flags,
|
|
int migratetype)
|
|
{
|
|
unsigned long flags;
|
|
struct page *page;
|
|
int cold = !!(gfp_flags & __GFP_COLD);
|
|
|
|
again:
|
|
if (likely(order == 0)) {
|
|
struct per_cpu_pages *pcp;
|
|
struct list_head *list;
|
|
|
|
local_irq_save(flags);
|
|
pcp = &this_cpu_ptr(zone->pageset)->pcp;
|
|
list = &pcp->lists[migratetype];
|
|
if (list_empty(list)) {
|
|
pcp->count += rmqueue_bulk(zone, 0,
|
|
pcp->batch, list,
|
|
migratetype, cold);
|
|
if (unlikely(list_empty(list)))
|
|
goto failed;
|
|
}
|
|
|
|
if (cold)
|
|
page = list_entry(list->prev, struct page, lru);
|
|
else
|
|
page = list_entry(list->next, struct page, lru);
|
|
|
|
list_del(&page->lru);
|
|
pcp->count--;
|
|
} else {
|
|
if (unlikely(gfp_flags & __GFP_NOFAIL)) {
|
|
/*
|
|
* __GFP_NOFAIL is not to be used in new code.
|
|
*
|
|
* All __GFP_NOFAIL callers should be fixed so that they
|
|
* properly detect and handle allocation failures.
|
|
*
|
|
* We most definitely don't want callers attempting to
|
|
* allocate greater than order-1 page units with
|
|
* __GFP_NOFAIL.
|
|
*/
|
|
WARN_ON_ONCE(order > 1);
|
|
}
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
page = __rmqueue(zone, order, migratetype);
|
|
spin_unlock(&zone->lock);
|
|
if (!page)
|
|
goto failed;
|
|
__mod_zone_page_state(zone, NR_FREE_PAGES, -(1 << order));
|
|
}
|
|
|
|
__count_zone_vm_events(PGALLOC, zone, 1 << order);
|
|
zone_statistics(preferred_zone, zone, gfp_flags);
|
|
local_irq_restore(flags);
|
|
|
|
VM_BUG_ON(bad_range(zone, page));
|
|
if (prep_new_page(page, order, gfp_flags))
|
|
goto again;
|
|
return page;
|
|
|
|
failed:
|
|
local_irq_restore(flags);
|
|
return NULL;
|
|
}
|
|
|
|
/* The ALLOC_WMARK bits are used as an index to zone->watermark */
|
|
#define ALLOC_WMARK_MIN WMARK_MIN
|
|
#define ALLOC_WMARK_LOW WMARK_LOW
|
|
#define ALLOC_WMARK_HIGH WMARK_HIGH
|
|
#define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
|
|
|
|
/* Mask to get the watermark bits */
|
|
#define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
|
|
|
|
#define ALLOC_HARDER 0x10 /* try to alloc harder */
|
|
#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
|
|
#define ALLOC_CPUSET 0x40 /* check for correct cpuset */
|
|
|
|
#ifdef CONFIG_FAIL_PAGE_ALLOC
|
|
|
|
static struct {
|
|
struct fault_attr attr;
|
|
|
|
u32 ignore_gfp_highmem;
|
|
u32 ignore_gfp_wait;
|
|
u32 min_order;
|
|
} fail_page_alloc = {
|
|
.attr = FAULT_ATTR_INITIALIZER,
|
|
.ignore_gfp_wait = 1,
|
|
.ignore_gfp_highmem = 1,
|
|
.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_wait && (gfp_mask & __GFP_WAIT))
|
|
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 | S_IRUSR | S_IWUSR;
|
|
struct dentry *dir;
|
|
|
|
dir = fault_create_debugfs_attr("fail_page_alloc", NULL,
|
|
&fail_page_alloc.attr);
|
|
if (IS_ERR(dir))
|
|
return PTR_ERR(dir);
|
|
|
|
if (!debugfs_create_bool("ignore-gfp-wait", mode, dir,
|
|
&fail_page_alloc.ignore_gfp_wait))
|
|
goto fail;
|
|
if (!debugfs_create_bool("ignore-gfp-highmem", mode, dir,
|
|
&fail_page_alloc.ignore_gfp_highmem))
|
|
goto fail;
|
|
if (!debugfs_create_u32("min-order", mode, dir,
|
|
&fail_page_alloc.min_order))
|
|
goto fail;
|
|
|
|
return 0;
|
|
fail:
|
|
debugfs_remove_recursive(dir);
|
|
|
|
return -ENOMEM;
|
|
}
|
|
|
|
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 */
|
|
|
|
/*
|
|
* Return true if free pages are above 'mark'. This takes into account the order
|
|
* of the allocation.
|
|
*/
|
|
static bool __zone_watermark_ok(struct zone *z, int order, unsigned long mark,
|
|
int classzone_idx, int alloc_flags, long free_pages)
|
|
{
|
|
/* free_pages my go negative - that's OK */
|
|
long min = mark;
|
|
long lowmem_reserve = z->lowmem_reserve[classzone_idx];
|
|
int o;
|
|
|
|
free_pages -= (1 << order) - 1;
|
|
if (alloc_flags & ALLOC_HIGH)
|
|
min -= min / 2;
|
|
if (alloc_flags & ALLOC_HARDER)
|
|
min -= min / 4;
|
|
|
|
if (free_pages <= min + lowmem_reserve)
|
|
return false;
|
|
for (o = 0; o < order; o++) {
|
|
/* At the next order, this order's pages become unavailable */
|
|
free_pages -= z->free_area[o].nr_free << o;
|
|
|
|
/* Require fewer higher order pages to be free */
|
|
min >>= 1;
|
|
|
|
if (free_pages <= min)
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
#ifdef CONFIG_MEMORY_ISOLATION
|
|
static inline unsigned long nr_zone_isolate_freepages(struct zone *zone)
|
|
{
|
|
if (unlikely(zone->nr_pageblock_isolate))
|
|
return zone->nr_pageblock_isolate * pageblock_nr_pages;
|
|
return 0;
|
|
}
|
|
#else
|
|
static inline unsigned long nr_zone_isolate_freepages(struct zone *zone)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
bool zone_watermark_ok(struct zone *z, int order, unsigned long mark,
|
|
int classzone_idx, int alloc_flags)
|
|
{
|
|
return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags,
|
|
zone_page_state(z, NR_FREE_PAGES));
|
|
}
|
|
|
|
bool zone_watermark_ok_safe(struct zone *z, int order, unsigned long mark,
|
|
int classzone_idx, int alloc_flags)
|
|
{
|
|
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);
|
|
|
|
/*
|
|
* If the zone has MIGRATE_ISOLATE type free pages, we should consider
|
|
* it. nr_zone_isolate_freepages is never accurate so kswapd might not
|
|
* sleep although it could do so. But this is more desirable for memory
|
|
* hotplug than sleeping which can cause a livelock in the direct
|
|
* reclaim path.
|
|
*/
|
|
free_pages -= nr_zone_isolate_freepages(z);
|
|
return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags,
|
|
free_pages);
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA
|
|
/*
|
|
* zlc_setup - Setup for "zonelist cache". Uses cached zone data to
|
|
* skip over zones that are not allowed by the cpuset, or that have
|
|
* been recently (in last second) found to be nearly full. See further
|
|
* comments in mmzone.h. Reduces cache footprint of zonelist scans
|
|
* that have to skip over a lot of full or unallowed zones.
|
|
*
|
|
* If the zonelist cache is present in the passed in zonelist, then
|
|
* returns a pointer to the allowed node mask (either the current
|
|
* tasks mems_allowed, or node_states[N_HIGH_MEMORY].)
|
|
*
|
|
* If the zonelist cache is not available for this zonelist, does
|
|
* nothing and returns NULL.
|
|
*
|
|
* If the fullzones BITMAP in the zonelist cache is stale (more than
|
|
* a second since last zap'd) then we zap it out (clear its bits.)
|
|
*
|
|
* We hold off even calling zlc_setup, until after we've checked the
|
|
* first zone in the zonelist, on the theory that most allocations will
|
|
* be satisfied from that first zone, so best to examine that zone as
|
|
* quickly as we can.
|
|
*/
|
|
static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
|
|
{
|
|
struct zonelist_cache *zlc; /* cached zonelist speedup info */
|
|
nodemask_t *allowednodes; /* zonelist_cache approximation */
|
|
|
|
zlc = zonelist->zlcache_ptr;
|
|
if (!zlc)
|
|
return NULL;
|
|
|
|
if (time_after(jiffies, zlc->last_full_zap + HZ)) {
|
|
bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
|
|
zlc->last_full_zap = jiffies;
|
|
}
|
|
|
|
allowednodes = !in_interrupt() && (alloc_flags & ALLOC_CPUSET) ?
|
|
&cpuset_current_mems_allowed :
|
|
&node_states[N_HIGH_MEMORY];
|
|
return allowednodes;
|
|
}
|
|
|
|
/*
|
|
* Given 'z' scanning a zonelist, run a couple of quick checks to see
|
|
* if it is worth looking at further for free memory:
|
|
* 1) Check that the zone isn't thought to be full (doesn't have its
|
|
* bit set in the zonelist_cache fullzones BITMAP).
|
|
* 2) Check that the zones node (obtained from the zonelist_cache
|
|
* z_to_n[] mapping) is allowed in the passed in allowednodes mask.
|
|
* Return true (non-zero) if zone is worth looking at further, or
|
|
* else return false (zero) if it is not.
|
|
*
|
|
* This check -ignores- the distinction between various watermarks,
|
|
* such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is
|
|
* found to be full for any variation of these watermarks, it will
|
|
* be considered full for up to one second by all requests, unless
|
|
* we are so low on memory on all allowed nodes that we are forced
|
|
* into the second scan of the zonelist.
|
|
*
|
|
* In the second scan we ignore this zonelist cache and exactly
|
|
* apply the watermarks to all zones, even it is slower to do so.
|
|
* We are low on memory in the second scan, and should leave no stone
|
|
* unturned looking for a free page.
|
|
*/
|
|
static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z,
|
|
nodemask_t *allowednodes)
|
|
{
|
|
struct zonelist_cache *zlc; /* cached zonelist speedup info */
|
|
int i; /* index of *z in zonelist zones */
|
|
int n; /* node that zone *z is on */
|
|
|
|
zlc = zonelist->zlcache_ptr;
|
|
if (!zlc)
|
|
return 1;
|
|
|
|
i = z - zonelist->_zonerefs;
|
|
n = zlc->z_to_n[i];
|
|
|
|
/* This zone is worth trying if it is allowed but not full */
|
|
return node_isset(n, *allowednodes) && !test_bit(i, zlc->fullzones);
|
|
}
|
|
|
|
/*
|
|
* Given 'z' scanning a zonelist, set the corresponding bit in
|
|
* zlc->fullzones, so that subsequent attempts to allocate a page
|
|
* from that zone don't waste time re-examining it.
|
|
*/
|
|
static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
|
|
{
|
|
struct zonelist_cache *zlc; /* cached zonelist speedup info */
|
|
int i; /* index of *z in zonelist zones */
|
|
|
|
zlc = zonelist->zlcache_ptr;
|
|
if (!zlc)
|
|
return;
|
|
|
|
i = z - zonelist->_zonerefs;
|
|
|
|
set_bit(i, zlc->fullzones);
|
|
}
|
|
|
|
/*
|
|
* clear all zones full, called after direct reclaim makes progress so that
|
|
* a zone that was recently full is not skipped over for up to a second
|
|
*/
|
|
static void zlc_clear_zones_full(struct zonelist *zonelist)
|
|
{
|
|
struct zonelist_cache *zlc; /* cached zonelist speedup info */
|
|
|
|
zlc = zonelist->zlcache_ptr;
|
|
if (!zlc)
|
|
return;
|
|
|
|
bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
|
|
}
|
|
|
|
#else /* CONFIG_NUMA */
|
|
|
|
static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z,
|
|
nodemask_t *allowednodes)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
|
|
{
|
|
}
|
|
|
|
static void zlc_clear_zones_full(struct zonelist *zonelist)
|
|
{
|
|
}
|
|
#endif /* CONFIG_NUMA */
|
|
|
|
/*
|
|
* get_page_from_freelist goes through the zonelist trying to allocate
|
|
* a page.
|
|
*/
|
|
static struct page *
|
|
get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order,
|
|
struct zonelist *zonelist, int high_zoneidx, int alloc_flags,
|
|
struct zone *preferred_zone, int migratetype)
|
|
{
|
|
struct zoneref *z;
|
|
struct page *page = NULL;
|
|
int classzone_idx;
|
|
struct zone *zone;
|
|
nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */
|
|
int zlc_active = 0; /* set if using zonelist_cache */
|
|
int did_zlc_setup = 0; /* just call zlc_setup() one time */
|
|
|
|
classzone_idx = zone_idx(preferred_zone);
|
|
zonelist_scan:
|
|
/*
|
|
* Scan zonelist, looking for a zone with enough free.
|
|
* See also cpuset_zone_allowed() comment in kernel/cpuset.c.
|
|
*/
|
|
for_each_zone_zonelist_nodemask(zone, z, zonelist,
|
|
high_zoneidx, nodemask) {
|
|
if (NUMA_BUILD && zlc_active &&
|
|
!zlc_zone_worth_trying(zonelist, z, allowednodes))
|
|
continue;
|
|
if ((alloc_flags & ALLOC_CPUSET) &&
|
|
!cpuset_zone_allowed_softwall(zone, gfp_mask))
|
|
continue;
|
|
/*
|
|
* When allocating a page cache page for writing, we
|
|
* want to get it from a zone that is within its dirty
|
|
* limit, such that no single zone holds more than its
|
|
* proportional share of globally allowed dirty pages.
|
|
* The dirty limits take into account the zone's
|
|
* lowmem reserves and high watermark so that kswapd
|
|
* should be able to balance it without having to
|
|
* write pages from its LRU list.
|
|
*
|
|
* This may look like it could increase pressure on
|
|
* lower zones by failing allocations in higher zones
|
|
* before they are full. But the pages that do spill
|
|
* over are limited as the lower zones are protected
|
|
* by this very same mechanism. It should not become
|
|
* a practical burden to them.
|
|
*
|
|
* XXX: For now, allow allocations to potentially
|
|
* exceed the per-zone dirty limit in the slowpath
|
|
* (ALLOC_WMARK_LOW unset) before going into reclaim,
|
|
* which is important when on a NUMA setup the allowed
|
|
* zones are together not big enough to reach the
|
|
* global limit. The proper fix for these situations
|
|
* will require awareness of zones in the
|
|
* dirty-throttling and the flusher threads.
|
|
*/
|
|
if ((alloc_flags & ALLOC_WMARK_LOW) &&
|
|
(gfp_mask & __GFP_WRITE) && !zone_dirty_ok(zone))
|
|
goto this_zone_full;
|
|
|
|
BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);
|
|
if (!(alloc_flags & ALLOC_NO_WATERMARKS)) {
|
|
unsigned long mark;
|
|
int ret;
|
|
|
|
mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK];
|
|
if (zone_watermark_ok(zone, order, mark,
|
|
classzone_idx, alloc_flags))
|
|
goto try_this_zone;
|
|
|
|
if (NUMA_BUILD && !did_zlc_setup && nr_online_nodes > 1) {
|
|
/*
|
|
* we do zlc_setup if there are multiple nodes
|
|
* and before considering the first zone allowed
|
|
* by the cpuset.
|
|
*/
|
|
allowednodes = zlc_setup(zonelist, alloc_flags);
|
|
zlc_active = 1;
|
|
did_zlc_setup = 1;
|
|
}
|
|
|
|
if (zone_reclaim_mode == 0)
|
|
goto this_zone_full;
|
|
|
|
/*
|
|
* As we may have just activated ZLC, check if the first
|
|
* eligible zone has failed zone_reclaim recently.
|
|
*/
|
|
if (NUMA_BUILD && zlc_active &&
|
|
!zlc_zone_worth_trying(zonelist, z, allowednodes))
|
|
continue;
|
|
|
|
ret = zone_reclaim(zone, gfp_mask, order);
|
|
switch (ret) {
|
|
case ZONE_RECLAIM_NOSCAN:
|
|
/* did not scan */
|
|
continue;
|
|
case ZONE_RECLAIM_FULL:
|
|
/* scanned but unreclaimable */
|
|
continue;
|
|
default:
|
|
/* did we reclaim enough */
|
|
if (!zone_watermark_ok(zone, order, mark,
|
|
classzone_idx, alloc_flags))
|
|
goto this_zone_full;
|
|
}
|
|
}
|
|
|
|
try_this_zone:
|
|
page = buffered_rmqueue(preferred_zone, zone, order,
|
|
gfp_mask, migratetype);
|
|
if (page)
|
|
break;
|
|
this_zone_full:
|
|
if (NUMA_BUILD)
|
|
zlc_mark_zone_full(zonelist, z);
|
|
}
|
|
|
|
if (unlikely(NUMA_BUILD && page == NULL && zlc_active)) {
|
|
/* Disable zlc cache for second zonelist scan */
|
|
zlc_active = 0;
|
|
goto zonelist_scan;
|
|
}
|
|
return page;
|
|
}
|
|
|
|
/*
|
|
* Large machines with many possible nodes should not always dump per-node
|
|
* meminfo in irq context.
|
|
*/
|
|
static inline bool should_suppress_show_mem(void)
|
|
{
|
|
bool ret = false;
|
|
|
|
#if NODES_SHIFT > 8
|
|
ret = in_interrupt();
|
|
#endif
|
|
return ret;
|
|
}
|
|
|
|
static DEFINE_RATELIMIT_STATE(nopage_rs,
|
|
DEFAULT_RATELIMIT_INTERVAL,
|
|
DEFAULT_RATELIMIT_BURST);
|
|
|
|
void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...)
|
|
{
|
|
unsigned int filter = SHOW_MEM_FILTER_NODES;
|
|
|
|
if ((gfp_mask & __GFP_NOWARN) || !__ratelimit(&nopage_rs) ||
|
|
debug_guardpage_minorder() > 0)
|
|
return;
|
|
|
|
/*
|
|
* 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 (test_thread_flag(TIF_MEMDIE) ||
|
|
(current->flags & (PF_MEMALLOC | PF_EXITING)))
|
|
filter &= ~SHOW_MEM_FILTER_NODES;
|
|
if (in_interrupt() || !(gfp_mask & __GFP_WAIT))
|
|
filter &= ~SHOW_MEM_FILTER_NODES;
|
|
|
|
if (fmt) {
|
|
struct va_format vaf;
|
|
va_list args;
|
|
|
|
va_start(args, fmt);
|
|
|
|
vaf.fmt = fmt;
|
|
vaf.va = &args;
|
|
|
|
pr_warn("%pV", &vaf);
|
|
|
|
va_end(args);
|
|
}
|
|
|
|
pr_warn("%s: page allocation failure: order:%d, mode:0x%x\n",
|
|
current->comm, order, gfp_mask);
|
|
|
|
dump_stack();
|
|
if (!should_suppress_show_mem())
|
|
show_mem(filter);
|
|
}
|
|
|
|
static inline int
|
|
should_alloc_retry(gfp_t gfp_mask, unsigned int order,
|
|
unsigned long did_some_progress,
|
|
unsigned long pages_reclaimed)
|
|
{
|
|
/* Do not loop if specifically requested */
|
|
if (gfp_mask & __GFP_NORETRY)
|
|
return 0;
|
|
|
|
/* Always retry if specifically requested */
|
|
if (gfp_mask & __GFP_NOFAIL)
|
|
return 1;
|
|
|
|
/*
|
|
* Suspend converts GFP_KERNEL to __GFP_WAIT which can prevent reclaim
|
|
* making forward progress without invoking OOM. Suspend also disables
|
|
* storage devices so kswapd will not help. Bail if we are suspending.
|
|
*/
|
|
if (!did_some_progress && pm_suspended_storage())
|
|
return 0;
|
|
|
|
/*
|
|
* In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
|
|
* means __GFP_NOFAIL, but that may not be true in other
|
|
* implementations.
|
|
*/
|
|
if (order <= PAGE_ALLOC_COSTLY_ORDER)
|
|
return 1;
|
|
|
|
/*
|
|
* For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
|
|
* specified, then we retry until we no longer reclaim any pages
|
|
* (above), or we've reclaimed an order of pages at least as
|
|
* large as the allocation's order. In both cases, if the
|
|
* allocation still fails, we stop retrying.
|
|
*/
|
|
if (gfp_mask & __GFP_REPEAT && pages_reclaimed < (1 << order))
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline struct page *
|
|
__alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
|
|
struct zonelist *zonelist, enum zone_type high_zoneidx,
|
|
nodemask_t *nodemask, struct zone *preferred_zone,
|
|
int migratetype)
|
|
{
|
|
struct page *page;
|
|
|
|
/* Acquire the OOM killer lock for the zones in zonelist */
|
|
if (!try_set_zonelist_oom(zonelist, gfp_mask)) {
|
|
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.
|
|
*/
|
|
page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask,
|
|
order, zonelist, high_zoneidx,
|
|
ALLOC_WMARK_HIGH|ALLOC_CPUSET,
|
|
preferred_zone, migratetype);
|
|
if (page)
|
|
goto out;
|
|
|
|
if (!(gfp_mask & __GFP_NOFAIL)) {
|
|
/* The OOM killer will not help higher order allocs */
|
|
if (order > PAGE_ALLOC_COSTLY_ORDER)
|
|
goto out;
|
|
/* The OOM killer does not needlessly kill tasks for lowmem */
|
|
if (high_zoneidx < ZONE_NORMAL)
|
|
goto out;
|
|
/*
|
|
* GFP_THISNODE contains __GFP_NORETRY and we never hit this.
|
|
* Sanity check for bare calls of __GFP_THISNODE, not real OOM.
|
|
* The caller should handle page allocation failure by itself if
|
|
* it specifies __GFP_THISNODE.
|
|
* Note: Hugepage uses it but will hit PAGE_ALLOC_COSTLY_ORDER.
|
|
*/
|
|
if (gfp_mask & __GFP_THISNODE)
|
|
goto out;
|
|
}
|
|
/* Exhausted what can be done so it's blamo time */
|
|
out_of_memory(zonelist, gfp_mask, order, nodemask, false);
|
|
|
|
out:
|
|
clear_zonelist_oom(zonelist, gfp_mask);
|
|
return page;
|
|
}
|
|
|
|
#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,
|
|
struct zonelist *zonelist, enum zone_type high_zoneidx,
|
|
nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
|
|
int migratetype, bool sync_migration,
|
|
bool *deferred_compaction,
|
|
unsigned long *did_some_progress)
|
|
{
|
|
struct page *page;
|
|
|
|
if (!order)
|
|
return NULL;
|
|
|
|
if (compaction_deferred(preferred_zone, order)) {
|
|
*deferred_compaction = true;
|
|
return NULL;
|
|
}
|
|
|
|
current->flags |= PF_MEMALLOC;
|
|
*did_some_progress = try_to_compact_pages(zonelist, order, gfp_mask,
|
|
nodemask, sync_migration);
|
|
current->flags &= ~PF_MEMALLOC;
|
|
if (*did_some_progress != COMPACT_SKIPPED) {
|
|
|
|
/* Page migration frees to the PCP lists but we want merging */
|
|
drain_pages(get_cpu());
|
|
put_cpu();
|
|
|
|
page = get_page_from_freelist(gfp_mask, nodemask,
|
|
order, zonelist, high_zoneidx,
|
|
alloc_flags & ~ALLOC_NO_WATERMARKS,
|
|
preferred_zone, migratetype);
|
|
if (page) {
|
|
preferred_zone->compact_considered = 0;
|
|
preferred_zone->compact_defer_shift = 0;
|
|
if (order >= preferred_zone->compact_order_failed)
|
|
preferred_zone->compact_order_failed = order + 1;
|
|
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);
|
|
|
|
/*
|
|
* As async compaction considers a subset of pageblocks, only
|
|
* defer if the failure was a sync compaction failure.
|
|
*/
|
|
if (sync_migration)
|
|
defer_compaction(preferred_zone, order);
|
|
|
|
cond_resched();
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
#else
|
|
static inline struct page *
|
|
__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
|
|
struct zonelist *zonelist, enum zone_type high_zoneidx,
|
|
nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
|
|
int migratetype, bool sync_migration,
|
|
bool *deferred_compaction,
|
|
unsigned long *did_some_progress)
|
|
{
|
|
return NULL;
|
|
}
|
|
#endif /* CONFIG_COMPACTION */
|
|
|
|
/* Perform direct synchronous page reclaim */
|
|
static int
|
|
__perform_reclaim(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist,
|
|
nodemask_t *nodemask)
|
|
{
|
|
struct reclaim_state reclaim_state;
|
|
int progress;
|
|
|
|
cond_resched();
|
|
|
|
/* We now go into synchronous reclaim */
|
|
cpuset_memory_pressure_bump();
|
|
current->flags |= PF_MEMALLOC;
|
|
lockdep_set_current_reclaim_state(gfp_mask);
|
|
reclaim_state.reclaimed_slab = 0;
|
|
current->reclaim_state = &reclaim_state;
|
|
|
|
progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask);
|
|
|
|
current->reclaim_state = NULL;
|
|
lockdep_clear_current_reclaim_state();
|
|
current->flags &= ~PF_MEMALLOC;
|
|
|
|
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,
|
|
struct zonelist *zonelist, enum zone_type high_zoneidx,
|
|
nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
|
|
int migratetype, unsigned long *did_some_progress)
|
|
{
|
|
struct page *page = NULL;
|
|
bool drained = false;
|
|
|
|
*did_some_progress = __perform_reclaim(gfp_mask, order, zonelist,
|
|
nodemask);
|
|
if (unlikely(!(*did_some_progress)))
|
|
return NULL;
|
|
|
|
/* After successful reclaim, reconsider all zones for allocation */
|
|
if (NUMA_BUILD)
|
|
zlc_clear_zones_full(zonelist);
|
|
|
|
retry:
|
|
page = get_page_from_freelist(gfp_mask, nodemask, order,
|
|
zonelist, high_zoneidx,
|
|
alloc_flags & ~ALLOC_NO_WATERMARKS,
|
|
preferred_zone, migratetype);
|
|
|
|
/*
|
|
* If an allocation failed after direct reclaim, it could be because
|
|
* pages are pinned on the per-cpu lists. Drain them and try again
|
|
*/
|
|
if (!page && !drained) {
|
|
drain_all_pages();
|
|
drained = true;
|
|
goto retry;
|
|
}
|
|
|
|
return page;
|
|
}
|
|
|
|
/*
|
|
* This is called in the allocator slow-path if the allocation request is of
|
|
* sufficient urgency to ignore watermarks and take other desperate measures
|
|
*/
|
|
static inline struct page *
|
|
__alloc_pages_high_priority(gfp_t gfp_mask, unsigned int order,
|
|
struct zonelist *zonelist, enum zone_type high_zoneidx,
|
|
nodemask_t *nodemask, struct zone *preferred_zone,
|
|
int migratetype)
|
|
{
|
|
struct page *page;
|
|
|
|
do {
|
|
page = get_page_from_freelist(gfp_mask, nodemask, order,
|
|
zonelist, high_zoneidx, ALLOC_NO_WATERMARKS,
|
|
preferred_zone, migratetype);
|
|
|
|
if (!page && gfp_mask & __GFP_NOFAIL)
|
|
wait_iff_congested(preferred_zone, BLK_RW_ASYNC, HZ/50);
|
|
} while (!page && (gfp_mask & __GFP_NOFAIL));
|
|
|
|
return page;
|
|
}
|
|
|
|
static inline
|
|
void wake_all_kswapd(unsigned int order, struct zonelist *zonelist,
|
|
enum zone_type high_zoneidx,
|
|
enum zone_type classzone_idx)
|
|
{
|
|
struct zoneref *z;
|
|
struct zone *zone;
|
|
|
|
for_each_zone_zonelist(zone, z, zonelist, high_zoneidx)
|
|
wakeup_kswapd(zone, order, classzone_idx);
|
|
}
|
|
|
|
static inline int
|
|
gfp_to_alloc_flags(gfp_t gfp_mask)
|
|
{
|
|
int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET;
|
|
const gfp_t wait = gfp_mask & __GFP_WAIT;
|
|
|
|
/* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
|
|
BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_HIGH);
|
|
|
|
/*
|
|
* 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 (!wait) and ALLOC_HIGH (__GFP_HIGH).
|
|
*/
|
|
alloc_flags |= (__force int) (gfp_mask & __GFP_HIGH);
|
|
|
|
if (!wait) {
|
|
/*
|
|
* 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 if GFP_ATOMIC (!wait) rather than fail alloc.
|
|
* See also cpuset_zone_allowed() comment in kernel/cpuset.c.
|
|
*/
|
|
alloc_flags &= ~ALLOC_CPUSET;
|
|
} else if (unlikely(rt_task(current)) && !in_interrupt())
|
|
alloc_flags |= ALLOC_HARDER;
|
|
|
|
if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) {
|
|
if (gfp_mask & __GFP_MEMALLOC)
|
|
alloc_flags |= ALLOC_NO_WATERMARKS;
|
|
else if (in_serving_softirq() && (current->flags & PF_MEMALLOC))
|
|
alloc_flags |= ALLOC_NO_WATERMARKS;
|
|
else if (!in_interrupt() &&
|
|
((current->flags & PF_MEMALLOC) ||
|
|
unlikely(test_thread_flag(TIF_MEMDIE))))
|
|
alloc_flags |= ALLOC_NO_WATERMARKS;
|
|
}
|
|
|
|
return alloc_flags;
|
|
}
|
|
|
|
bool gfp_pfmemalloc_allowed(gfp_t gfp_mask)
|
|
{
|
|
return !!(gfp_to_alloc_flags(gfp_mask) & ALLOC_NO_WATERMARKS);
|
|
}
|
|
|
|
static inline struct page *
|
|
__alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
|
|
struct zonelist *zonelist, enum zone_type high_zoneidx,
|
|
nodemask_t *nodemask, struct zone *preferred_zone,
|
|
int migratetype)
|
|
{
|
|
const gfp_t wait = gfp_mask & __GFP_WAIT;
|
|
struct page *page = NULL;
|
|
int alloc_flags;
|
|
unsigned long pages_reclaimed = 0;
|
|
unsigned long did_some_progress;
|
|
bool sync_migration = false;
|
|
bool deferred_compaction = false;
|
|
|
|
/*
|
|
* In the slowpath, we sanity check order to avoid ever trying to
|
|
* reclaim >= MAX_ORDER areas which will never succeed. Callers may
|
|
* be using allocators in order of preference for an area that is
|
|
* too large.
|
|
*/
|
|
if (order >= MAX_ORDER) {
|
|
WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN));
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
|
|
* __GFP_NOWARN set) should not cause reclaim since the subsystem
|
|
* (f.e. slab) using GFP_THISNODE may choose to trigger reclaim
|
|
* using a larger set of nodes after it has established that the
|
|
* allowed per node queues are empty and that nodes are
|
|
* over allocated.
|
|
*/
|
|
if (NUMA_BUILD && (gfp_mask & GFP_THISNODE) == GFP_THISNODE)
|
|
goto nopage;
|
|
|
|
restart:
|
|
if (!(gfp_mask & __GFP_NO_KSWAPD))
|
|
wake_all_kswapd(order, zonelist, high_zoneidx,
|
|
zone_idx(preferred_zone));
|
|
|
|
/*
|
|
* OK, we're below the kswapd watermark and have kicked background
|
|
* reclaim. Now things get more complex, so set up alloc_flags according
|
|
* to how we want to proceed.
|
|
*/
|
|
alloc_flags = gfp_to_alloc_flags(gfp_mask);
|
|
|
|
/*
|
|
* Find the true preferred zone if the allocation is unconstrained by
|
|
* cpusets.
|
|
*/
|
|
if (!(alloc_flags & ALLOC_CPUSET) && !nodemask)
|
|
first_zones_zonelist(zonelist, high_zoneidx, NULL,
|
|
&preferred_zone);
|
|
|
|
rebalance:
|
|
/* This is the last chance, in general, before the goto nopage. */
|
|
page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist,
|
|
high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS,
|
|
preferred_zone, migratetype);
|
|
if (page)
|
|
goto got_pg;
|
|
|
|
/* Allocate without watermarks if the context allows */
|
|
if (alloc_flags & ALLOC_NO_WATERMARKS) {
|
|
/*
|
|
* Ignore mempolicies if ALLOC_NO_WATERMARKS on the grounds
|
|
* the allocation is high priority and these type of
|
|
* allocations are system rather than user orientated
|
|
*/
|
|
zonelist = node_zonelist(numa_node_id(), gfp_mask);
|
|
|
|
page = __alloc_pages_high_priority(gfp_mask, order,
|
|
zonelist, high_zoneidx, nodemask,
|
|
preferred_zone, migratetype);
|
|
if (page) {
|
|
/*
|
|
* page->pfmemalloc is set 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.
|
|
*/
|
|
page->pfmemalloc = true;
|
|
goto got_pg;
|
|
}
|
|
}
|
|
|
|
/* Atomic allocations - we can't balance anything */
|
|
if (!wait)
|
|
goto nopage;
|
|
|
|
/* Avoid recursion of direct reclaim */
|
|
if (current->flags & PF_MEMALLOC)
|
|
goto nopage;
|
|
|
|
/* Avoid allocations with no watermarks from looping endlessly */
|
|
if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL))
|
|
goto nopage;
|
|
|
|
/*
|
|
* Try direct compaction. The first pass is asynchronous. Subsequent
|
|
* attempts after direct reclaim are synchronous
|
|
*/
|
|
page = __alloc_pages_direct_compact(gfp_mask, order,
|
|
zonelist, high_zoneidx,
|
|
nodemask,
|
|
alloc_flags, preferred_zone,
|
|
migratetype, sync_migration,
|
|
&deferred_compaction,
|
|
&did_some_progress);
|
|
if (page)
|
|
goto got_pg;
|
|
sync_migration = true;
|
|
|
|
/*
|
|
* If compaction is deferred for high-order allocations, it is because
|
|
* sync compaction recently failed. In this is the case and the caller
|
|
* has requested the system not be heavily disrupted, fail the
|
|
* allocation now instead of entering direct reclaim
|
|
*/
|
|
if (deferred_compaction && (gfp_mask & __GFP_NO_KSWAPD))
|
|
goto nopage;
|
|
|
|
/* Try direct reclaim and then allocating */
|
|
page = __alloc_pages_direct_reclaim(gfp_mask, order,
|
|
zonelist, high_zoneidx,
|
|
nodemask,
|
|
alloc_flags, preferred_zone,
|
|
migratetype, &did_some_progress);
|
|
if (page)
|
|
goto got_pg;
|
|
|
|
/*
|
|
* If we failed to make any progress reclaiming, then we are
|
|
* running out of options and have to consider going OOM
|
|
*/
|
|
if (!did_some_progress) {
|
|
if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) {
|
|
if (oom_killer_disabled)
|
|
goto nopage;
|
|
/* Coredumps can quickly deplete all memory reserves */
|
|
if ((current->flags & PF_DUMPCORE) &&
|
|
!(gfp_mask & __GFP_NOFAIL))
|
|
goto nopage;
|
|
page = __alloc_pages_may_oom(gfp_mask, order,
|
|
zonelist, high_zoneidx,
|
|
nodemask, preferred_zone,
|
|
migratetype);
|
|
if (page)
|
|
goto got_pg;
|
|
|
|
if (!(gfp_mask & __GFP_NOFAIL)) {
|
|
/*
|
|
* The oom killer is not called for high-order
|
|
* allocations that may fail, so if no progress
|
|
* is being made, there are no other options and
|
|
* retrying is unlikely to help.
|
|
*/
|
|
if (order > PAGE_ALLOC_COSTLY_ORDER)
|
|
goto nopage;
|
|
/*
|
|
* The oom killer is not called for lowmem
|
|
* allocations to prevent needlessly killing
|
|
* innocent tasks.
|
|
*/
|
|
if (high_zoneidx < ZONE_NORMAL)
|
|
goto nopage;
|
|
}
|
|
|
|
goto restart;
|
|
}
|
|
}
|
|
|
|
/* Check if we should retry the allocation */
|
|
pages_reclaimed += did_some_progress;
|
|
if (should_alloc_retry(gfp_mask, order, did_some_progress,
|
|
pages_reclaimed)) {
|
|
/* Wait for some write requests to complete then retry */
|
|
wait_iff_congested(preferred_zone, BLK_RW_ASYNC, HZ/50);
|
|
goto rebalance;
|
|
} else {
|
|
/*
|
|
* High-order allocations do not necessarily loop after
|
|
* direct reclaim and reclaim/compaction depends on compaction
|
|
* being called after reclaim so call directly if necessary
|
|
*/
|
|
page = __alloc_pages_direct_compact(gfp_mask, order,
|
|
zonelist, high_zoneidx,
|
|
nodemask,
|
|
alloc_flags, preferred_zone,
|
|
migratetype, sync_migration,
|
|
&deferred_compaction,
|
|
&did_some_progress);
|
|
if (page)
|
|
goto got_pg;
|
|
}
|
|
|
|
nopage:
|
|
warn_alloc_failed(gfp_mask, order, NULL);
|
|
return page;
|
|
got_pg:
|
|
if (kmemcheck_enabled)
|
|
kmemcheck_pagealloc_alloc(page, order, gfp_mask);
|
|
|
|
return page;
|
|
}
|
|
|
|
/*
|
|
* This is the 'heart' of the zoned buddy allocator.
|
|
*/
|
|
struct page *
|
|
__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
|
|
struct zonelist *zonelist, nodemask_t *nodemask)
|
|
{
|
|
enum zone_type high_zoneidx = gfp_zone(gfp_mask);
|
|
struct zone *preferred_zone;
|
|
struct page *page = NULL;
|
|
int migratetype = allocflags_to_migratetype(gfp_mask);
|
|
unsigned int cpuset_mems_cookie;
|
|
|
|
gfp_mask &= gfp_allowed_mask;
|
|
|
|
lockdep_trace_alloc(gfp_mask);
|
|
|
|
might_sleep_if(gfp_mask & __GFP_WAIT);
|
|
|
|
if (should_fail_alloc_page(gfp_mask, order))
|
|
return NULL;
|
|
|
|
/*
|
|
* Check the zones suitable for the gfp_mask contain at least one
|
|
* valid zone. It's possible to have an empty zonelist as a result
|
|
* of GFP_THISNODE and a memoryless node
|
|
*/
|
|
if (unlikely(!zonelist->_zonerefs->zone))
|
|
return NULL;
|
|
|
|
retry_cpuset:
|
|
cpuset_mems_cookie = get_mems_allowed();
|
|
|
|
/* The preferred zone is used for statistics later */
|
|
first_zones_zonelist(zonelist, high_zoneidx,
|
|
nodemask ? : &cpuset_current_mems_allowed,
|
|
&preferred_zone);
|
|
if (!preferred_zone)
|
|
goto out;
|
|
|
|
/* First allocation attempt */
|
|
page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
|
|
zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET,
|
|
preferred_zone, migratetype);
|
|
if (unlikely(!page))
|
|
page = __alloc_pages_slowpath(gfp_mask, order,
|
|
zonelist, high_zoneidx, nodemask,
|
|
preferred_zone, migratetype);
|
|
else
|
|
page->pfmemalloc = false;
|
|
|
|
trace_mm_page_alloc(page, order, gfp_mask, migratetype);
|
|
|
|
out:
|
|
/*
|
|
* When updating a task's mems_allowed, it is possible to race with
|
|
* parallel threads in such a way that an allocation can fail while
|
|
* the mask is being updated. If a page allocation is about to fail,
|
|
* check if the cpuset changed during allocation and if so, retry.
|
|
*/
|
|
if (unlikely(!put_mems_allowed(cpuset_mems_cookie) && !page))
|
|
goto retry_cpuset;
|
|
|
|
return page;
|
|
}
|
|
EXPORT_SYMBOL(__alloc_pages_nodemask);
|
|
|
|
/*
|
|
* Common helper functions.
|
|
*/
|
|
unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order)
|
|
{
|
|
struct page *page;
|
|
|
|
/*
|
|
* __get_free_pages() returns a 32-bit address, which cannot represent
|
|
* a highmem page
|
|
*/
|
|
VM_BUG_ON((gfp_mask & __GFP_HIGHMEM) != 0);
|
|
|
|
page = alloc_pages(gfp_mask, 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);
|
|
|
|
void __free_pages(struct page *page, unsigned int order)
|
|
{
|
|
if (put_page_testzero(page)) {
|
|
if (order == 0)
|
|
free_hot_cold_page(page, 0);
|
|
else
|
|
__free_pages_ok(page, 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);
|
|
|
|
static void *make_alloc_exact(unsigned long addr, unsigned 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
|
|
*
|
|
* 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().
|
|
*/
|
|
void *alloc_pages_exact(size_t size, gfp_t gfp_mask)
|
|
{
|
|
unsigned int order = get_order(size);
|
|
unsigned long addr;
|
|
|
|
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
|
|
*
|
|
* Like alloc_pages_exact(), but try to allocate on node nid first before falling
|
|
* back.
|
|
* Note this is not alloc_pages_exact_node() which allocates on a specific node,
|
|
* but is not exact.
|
|
*/
|
|
void *alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask)
|
|
{
|
|
unsigned order = get_order(size);
|
|
struct page *p = alloc_pages_node(nid, gfp_mask, order);
|
|
if (!p)
|
|
return NULL;
|
|
return make_alloc_exact((unsigned long)page_address(p), order, size);
|
|
}
|
|
EXPORT_SYMBOL(alloc_pages_exact_nid);
|
|
|
|
/**
|
|
* 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);
|
|
|
|
static unsigned int nr_free_zone_pages(int offset)
|
|
{
|
|
struct zoneref *z;
|
|
struct zone *zone;
|
|
|
|
/* Just pick one node, since fallback list is circular */
|
|
unsigned int sum = 0;
|
|
|
|
struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL);
|
|
|
|
for_each_zone_zonelist(zone, z, zonelist, offset) {
|
|
unsigned long size = zone->present_pages;
|
|
unsigned long high = high_wmark_pages(zone);
|
|
if (size > high)
|
|
sum += size - high;
|
|
}
|
|
|
|
return sum;
|
|
}
|
|
|
|
/*
|
|
* Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
|
|
*/
|
|
unsigned int nr_free_buffer_pages(void)
|
|
{
|
|
return nr_free_zone_pages(gfp_zone(GFP_USER));
|
|
}
|
|
EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
|
|
|
|
/*
|
|
* Amount of free RAM allocatable within all zones
|
|
*/
|
|
unsigned int nr_free_pagecache_pages(void)
|
|
{
|
|
return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
|
|
}
|
|
|
|
static inline void show_node(struct zone *zone)
|
|
{
|
|
if (NUMA_BUILD)
|
|
printk("Node %d ", zone_to_nid(zone));
|
|
}
|
|
|
|
void si_meminfo(struct sysinfo *val)
|
|
{
|
|
val->totalram = totalram_pages;
|
|
val->sharedram = 0;
|
|
val->freeram = global_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)
|
|
{
|
|
pg_data_t *pgdat = NODE_DATA(nid);
|
|
|
|
val->totalram = pgdat->node_present_pages;
|
|
val->freeram = node_page_state(nid, NR_FREE_PAGES);
|
|
#ifdef CONFIG_HIGHMEM
|
|
val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].present_pages;
|
|
val->freehigh = zone_page_state(&pgdat->node_zones[ZONE_HIGHMEM],
|
|
NR_FREE_PAGES);
|
|
#else
|
|
val->totalhigh = 0;
|
|
val->freehigh = 0;
|
|
#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().
|
|
*/
|
|
bool skip_free_areas_node(unsigned int flags, int nid)
|
|
{
|
|
bool ret = false;
|
|
unsigned int cpuset_mems_cookie;
|
|
|
|
if (!(flags & SHOW_MEM_FILTER_NODES))
|
|
goto out;
|
|
|
|
do {
|
|
cpuset_mems_cookie = get_mems_allowed();
|
|
ret = !node_isset(nid, cpuset_current_mems_allowed);
|
|
} while (!put_mems_allowed(cpuset_mems_cookie));
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
#define K(x) ((x) << (PAGE_SHIFT-10))
|
|
|
|
/*
|
|
* 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.
|
|
* Suppresses nodes that are not allowed by current's cpuset if
|
|
* SHOW_MEM_FILTER_NODES is passed.
|
|
*/
|
|
void show_free_areas(unsigned int filter)
|
|
{
|
|
int cpu;
|
|
struct zone *zone;
|
|
|
|
for_each_populated_zone(zone) {
|
|
if (skip_free_areas_node(filter, zone_to_nid(zone)))
|
|
continue;
|
|
show_node(zone);
|
|
printk("%s per-cpu:\n", zone->name);
|
|
|
|
for_each_online_cpu(cpu) {
|
|
struct per_cpu_pageset *pageset;
|
|
|
|
pageset = per_cpu_ptr(zone->pageset, cpu);
|
|
|
|
printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n",
|
|
cpu, pageset->pcp.high,
|
|
pageset->pcp.batch, pageset->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 unstable:%lu\n"
|
|
" free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n"
|
|
" mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n",
|
|
global_page_state(NR_ACTIVE_ANON),
|
|
global_page_state(NR_INACTIVE_ANON),
|
|
global_page_state(NR_ISOLATED_ANON),
|
|
global_page_state(NR_ACTIVE_FILE),
|
|
global_page_state(NR_INACTIVE_FILE),
|
|
global_page_state(NR_ISOLATED_FILE),
|
|
global_page_state(NR_UNEVICTABLE),
|
|
global_page_state(NR_FILE_DIRTY),
|
|
global_page_state(NR_WRITEBACK),
|
|
global_page_state(NR_UNSTABLE_NFS),
|
|
global_page_state(NR_FREE_PAGES),
|
|
global_page_state(NR_SLAB_RECLAIMABLE),
|
|
global_page_state(NR_SLAB_UNRECLAIMABLE),
|
|
global_page_state(NR_FILE_MAPPED),
|
|
global_page_state(NR_SHMEM),
|
|
global_page_state(NR_PAGETABLE),
|
|
global_page_state(NR_BOUNCE));
|
|
|
|
for_each_populated_zone(zone) {
|
|
int i;
|
|
|
|
if (skip_free_areas_node(filter, zone_to_nid(zone)))
|
|
continue;
|
|
show_node(zone);
|
|
printk("%s"
|
|
" free:%lukB"
|
|
" min:%lukB"
|
|
" low:%lukB"
|
|
" high:%lukB"
|
|
" active_anon:%lukB"
|
|
" inactive_anon:%lukB"
|
|
" active_file:%lukB"
|
|
" inactive_file:%lukB"
|
|
" unevictable:%lukB"
|
|
" isolated(anon):%lukB"
|
|
" isolated(file):%lukB"
|
|
" present:%lukB"
|
|
" mlocked:%lukB"
|
|
" dirty:%lukB"
|
|
" writeback:%lukB"
|
|
" mapped:%lukB"
|
|
" shmem:%lukB"
|
|
" slab_reclaimable:%lukB"
|
|
" slab_unreclaimable:%lukB"
|
|
" kernel_stack:%lukB"
|
|
" pagetables:%lukB"
|
|
" unstable:%lukB"
|
|
" bounce:%lukB"
|
|
" writeback_tmp:%lukB"
|
|
" pages_scanned:%lu"
|
|
" all_unreclaimable? %s"
|
|
"\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_page_state(zone, NR_ACTIVE_ANON)),
|
|
K(zone_page_state(zone, NR_INACTIVE_ANON)),
|
|
K(zone_page_state(zone, NR_ACTIVE_FILE)),
|
|
K(zone_page_state(zone, NR_INACTIVE_FILE)),
|
|
K(zone_page_state(zone, NR_UNEVICTABLE)),
|
|
K(zone_page_state(zone, NR_ISOLATED_ANON)),
|
|
K(zone_page_state(zone, NR_ISOLATED_FILE)),
|
|
K(zone->present_pages),
|
|
K(zone_page_state(zone, NR_MLOCK)),
|
|
K(zone_page_state(zone, NR_FILE_DIRTY)),
|
|
K(zone_page_state(zone, NR_WRITEBACK)),
|
|
K(zone_page_state(zone, NR_FILE_MAPPED)),
|
|
K(zone_page_state(zone, NR_SHMEM)),
|
|
K(zone_page_state(zone, NR_SLAB_RECLAIMABLE)),
|
|
K(zone_page_state(zone, NR_SLAB_UNRECLAIMABLE)),
|
|
zone_page_state(zone, NR_KERNEL_STACK) *
|
|
THREAD_SIZE / 1024,
|
|
K(zone_page_state(zone, NR_PAGETABLE)),
|
|
K(zone_page_state(zone, NR_UNSTABLE_NFS)),
|
|
K(zone_page_state(zone, NR_BOUNCE)),
|
|
K(zone_page_state(zone, NR_WRITEBACK_TEMP)),
|
|
zone->pages_scanned,
|
|
(zone->all_unreclaimable ? "yes" : "no")
|
|
);
|
|
printk("lowmem_reserve[]:");
|
|
for (i = 0; i < MAX_NR_ZONES; i++)
|
|
printk(" %lu", zone->lowmem_reserve[i]);
|
|
printk("\n");
|
|
}
|
|
|
|
for_each_populated_zone(zone) {
|
|
unsigned long nr[MAX_ORDER], flags, order, total = 0;
|
|
|
|
if (skip_free_areas_node(filter, zone_to_nid(zone)))
|
|
continue;
|
|
show_node(zone);
|
|
printk("%s: ", zone->name);
|
|
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
for (order = 0; order < MAX_ORDER; order++) {
|
|
nr[order] = zone->free_area[order].nr_free;
|
|
total += nr[order] << order;
|
|
}
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
for (order = 0; order < MAX_ORDER; order++)
|
|
printk("%lu*%lukB ", nr[order], K(1UL) << order);
|
|
printk("= %lukB\n", K(total));
|
|
}
|
|
|
|
printk("%ld total pagecache pages\n", global_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_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist,
|
|
int nr_zones, enum zone_type zone_type)
|
|
{
|
|
struct zone *zone;
|
|
|
|
BUG_ON(zone_type >= MAX_NR_ZONES);
|
|
zone_type++;
|
|
|
|
do {
|
|
zone_type--;
|
|
zone = pgdat->node_zones + zone_type;
|
|
if (populated_zone(zone)) {
|
|
zoneref_set_zone(zone,
|
|
&zonelist->_zonerefs[nr_zones++]);
|
|
check_highest_zone(zone_type);
|
|
}
|
|
|
|
} while (zone_type);
|
|
return nr_zones;
|
|
}
|
|
|
|
|
|
/*
|
|
* zonelist_order:
|
|
* 0 = automatic detection of better ordering.
|
|
* 1 = order by ([node] distance, -zonetype)
|
|
* 2 = order by (-zonetype, [node] distance)
|
|
*
|
|
* If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
|
|
* the same zonelist. So only NUMA can configure this param.
|
|
*/
|
|
#define ZONELIST_ORDER_DEFAULT 0
|
|
#define ZONELIST_ORDER_NODE 1
|
|
#define ZONELIST_ORDER_ZONE 2
|
|
|
|
/* zonelist order in the kernel.
|
|
* set_zonelist_order() will set this to NODE or ZONE.
|
|
*/
|
|
static int current_zonelist_order = ZONELIST_ORDER_DEFAULT;
|
|
static char zonelist_order_name[3][8] = {"Default", "Node", "Zone"};
|
|
|
|
|
|
#ifdef CONFIG_NUMA
|
|
/* The value user specified ....changed by config */
|
|
static int user_zonelist_order = ZONELIST_ORDER_DEFAULT;
|
|
/* string for sysctl */
|
|
#define NUMA_ZONELIST_ORDER_LEN 16
|
|
char numa_zonelist_order[16] = "default";
|
|
|
|
/*
|
|
* interface for configure zonelist ordering.
|
|
* command line option "numa_zonelist_order"
|
|
* = "[dD]efault - default, automatic configuration.
|
|
* = "[nN]ode - order by node locality, then by zone within node
|
|
* = "[zZ]one - order by zone, then by locality within zone
|
|
*/
|
|
|
|
static int __parse_numa_zonelist_order(char *s)
|
|
{
|
|
if (*s == 'd' || *s == 'D') {
|
|
user_zonelist_order = ZONELIST_ORDER_DEFAULT;
|
|
} else if (*s == 'n' || *s == 'N') {
|
|
user_zonelist_order = ZONELIST_ORDER_NODE;
|
|
} else if (*s == 'z' || *s == 'Z') {
|
|
user_zonelist_order = ZONELIST_ORDER_ZONE;
|
|
} else {
|
|
printk(KERN_WARNING
|
|
"Ignoring invalid numa_zonelist_order value: "
|
|
"%s\n", s);
|
|
return -EINVAL;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static __init int setup_numa_zonelist_order(char *s)
|
|
{
|
|
int ret;
|
|
|
|
if (!s)
|
|
return 0;
|
|
|
|
ret = __parse_numa_zonelist_order(s);
|
|
if (ret == 0)
|
|
strlcpy(numa_zonelist_order, s, NUMA_ZONELIST_ORDER_LEN);
|
|
|
|
return ret;
|
|
}
|
|
early_param("numa_zonelist_order", setup_numa_zonelist_order);
|
|
|
|
/*
|
|
* sysctl handler for numa_zonelist_order
|
|
*/
|
|
int numa_zonelist_order_handler(ctl_table *table, int write,
|
|
void __user *buffer, size_t *length,
|
|
loff_t *ppos)
|
|
{
|
|
char saved_string[NUMA_ZONELIST_ORDER_LEN];
|
|
int ret;
|
|
static DEFINE_MUTEX(zl_order_mutex);
|
|
|
|
mutex_lock(&zl_order_mutex);
|
|
if (write)
|
|
strcpy(saved_string, (char*)table->data);
|
|
ret = proc_dostring(table, write, buffer, length, ppos);
|
|
if (ret)
|
|
goto out;
|
|
if (write) {
|
|
int oldval = user_zonelist_order;
|
|
if (__parse_numa_zonelist_order((char*)table->data)) {
|
|
/*
|
|
* bogus value. restore saved string
|
|
*/
|
|
strncpy((char*)table->data, saved_string,
|
|
NUMA_ZONELIST_ORDER_LEN);
|
|
user_zonelist_order = oldval;
|
|
} else if (oldval != user_zonelist_order) {
|
|
mutex_lock(&zonelists_mutex);
|
|
build_all_zonelists(NULL, NULL);
|
|
mutex_unlock(&zonelists_mutex);
|
|
}
|
|
}
|
|
out:
|
|
mutex_unlock(&zl_order_mutex);
|
|
return ret;
|
|
}
|
|
|
|
|
|
#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.
|
|
* It returns -1 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 = -1;
|
|
const struct cpumask *tmp = cpumask_of_node(0);
|
|
|
|
/* 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_HIGH_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 */
|
|
tmp = cpumask_of_node(n);
|
|
if (!cpumask_empty(tmp))
|
|
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)
|
|
{
|
|
int j;
|
|
struct zonelist *zonelist;
|
|
|
|
zonelist = &pgdat->node_zonelists[0];
|
|
for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++)
|
|
;
|
|
j = build_zonelists_node(NODE_DATA(node), zonelist, j,
|
|
MAX_NR_ZONES - 1);
|
|
zonelist->_zonerefs[j].zone = NULL;
|
|
zonelist->_zonerefs[j].zone_idx = 0;
|
|
}
|
|
|
|
/*
|
|
* Build gfp_thisnode zonelists
|
|
*/
|
|
static void build_thisnode_zonelists(pg_data_t *pgdat)
|
|
{
|
|
int j;
|
|
struct zonelist *zonelist;
|
|
|
|
zonelist = &pgdat->node_zonelists[1];
|
|
j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1);
|
|
zonelist->_zonerefs[j].zone = NULL;
|
|
zonelist->_zonerefs[j].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 int node_order[MAX_NUMNODES];
|
|
|
|
static void build_zonelists_in_zone_order(pg_data_t *pgdat, int nr_nodes)
|
|
{
|
|
int pos, j, node;
|
|
int zone_type; /* needs to be signed */
|
|
struct zone *z;
|
|
struct zonelist *zonelist;
|
|
|
|
zonelist = &pgdat->node_zonelists[0];
|
|
pos = 0;
|
|
for (zone_type = MAX_NR_ZONES - 1; zone_type >= 0; zone_type--) {
|
|
for (j = 0; j < nr_nodes; j++) {
|
|
node = node_order[j];
|
|
z = &NODE_DATA(node)->node_zones[zone_type];
|
|
if (populated_zone(z)) {
|
|
zoneref_set_zone(z,
|
|
&zonelist->_zonerefs[pos++]);
|
|
check_highest_zone(zone_type);
|
|
}
|
|
}
|
|
}
|
|
zonelist->_zonerefs[pos].zone = NULL;
|
|
zonelist->_zonerefs[pos].zone_idx = 0;
|
|
}
|
|
|
|
static int default_zonelist_order(void)
|
|
{
|
|
int nid, zone_type;
|
|
unsigned long low_kmem_size,total_size;
|
|
struct zone *z;
|
|
int average_size;
|
|
/*
|
|
* ZONE_DMA and ZONE_DMA32 can be very small area in the system.
|
|
* If they are really small and used heavily, the system can fall
|
|
* into OOM very easily.
|
|
* This function detect ZONE_DMA/DMA32 size and configures zone order.
|
|
*/
|
|
/* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
|
|
low_kmem_size = 0;
|
|
total_size = 0;
|
|
for_each_online_node(nid) {
|
|
for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
|
|
z = &NODE_DATA(nid)->node_zones[zone_type];
|
|
if (populated_zone(z)) {
|
|
if (zone_type < ZONE_NORMAL)
|
|
low_kmem_size += z->present_pages;
|
|
total_size += z->present_pages;
|
|
} else if (zone_type == ZONE_NORMAL) {
|
|
/*
|
|
* If any node has only lowmem, then node order
|
|
* is preferred to allow kernel allocations
|
|
* locally; otherwise, they can easily infringe
|
|
* on other nodes when there is an abundance of
|
|
* lowmem available to allocate from.
|
|
*/
|
|
return ZONELIST_ORDER_NODE;
|
|
}
|
|
}
|
|
}
|
|
if (!low_kmem_size || /* there are no DMA area. */
|
|
low_kmem_size > total_size/2) /* DMA/DMA32 is big. */
|
|
return ZONELIST_ORDER_NODE;
|
|
/*
|
|
* look into each node's config.
|
|
* If there is a node whose DMA/DMA32 memory is very big area on
|
|
* local memory, NODE_ORDER may be suitable.
|
|
*/
|
|
average_size = total_size /
|
|
(nodes_weight(node_states[N_HIGH_MEMORY]) + 1);
|
|
for_each_online_node(nid) {
|
|
low_kmem_size = 0;
|
|
total_size = 0;
|
|
for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
|
|
z = &NODE_DATA(nid)->node_zones[zone_type];
|
|
if (populated_zone(z)) {
|
|
if (zone_type < ZONE_NORMAL)
|
|
low_kmem_size += z->present_pages;
|
|
total_size += z->present_pages;
|
|
}
|
|
}
|
|
if (low_kmem_size &&
|
|
total_size > average_size && /* ignore small node */
|
|
low_kmem_size > total_size * 70/100)
|
|
return ZONELIST_ORDER_NODE;
|
|
}
|
|
return ZONELIST_ORDER_ZONE;
|
|
}
|
|
|
|
static void set_zonelist_order(void)
|
|
{
|
|
if (user_zonelist_order == ZONELIST_ORDER_DEFAULT)
|
|
current_zonelist_order = default_zonelist_order();
|
|
else
|
|
current_zonelist_order = user_zonelist_order;
|
|
}
|
|
|
|
static void build_zonelists(pg_data_t *pgdat)
|
|
{
|
|
int j, node, load;
|
|
enum zone_type i;
|
|
nodemask_t used_mask;
|
|
int local_node, prev_node;
|
|
struct zonelist *zonelist;
|
|
int order = current_zonelist_order;
|
|
|
|
/* initialize zonelists */
|
|
for (i = 0; i < MAX_ZONELISTS; i++) {
|
|
zonelist = pgdat->node_zonelists + i;
|
|
zonelist->_zonerefs[0].zone = NULL;
|
|
zonelist->_zonerefs[0].zone_idx = 0;
|
|
}
|
|
|
|
/* NUMA-aware ordering of nodes */
|
|
local_node = pgdat->node_id;
|
|
load = nr_online_nodes;
|
|
prev_node = local_node;
|
|
nodes_clear(used_mask);
|
|
|
|
memset(node_order, 0, sizeof(node_order));
|
|
j = 0;
|
|
|
|
while ((node = find_next_best_node(local_node, &used_mask)) >= 0) {
|
|
int distance = node_distance(local_node, node);
|
|
|
|
/*
|
|
* If another node is sufficiently far away then it is better
|
|
* to reclaim pages in a zone before going off node.
|
|
*/
|
|
if (distance > RECLAIM_DISTANCE)
|
|
zone_reclaim_mode = 1;
|
|
|
|
/*
|
|
* 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 (distance != node_distance(local_node, prev_node))
|
|
node_load[node] = load;
|
|
|
|
prev_node = node;
|
|
load--;
|
|
if (order == ZONELIST_ORDER_NODE)
|
|
build_zonelists_in_node_order(pgdat, node);
|
|
else
|
|
node_order[j++] = node; /* remember order */
|
|
}
|
|
|
|
if (order == ZONELIST_ORDER_ZONE) {
|
|
/* calculate node order -- i.e., DMA last! */
|
|
build_zonelists_in_zone_order(pgdat, j);
|
|
}
|
|
|
|
build_thisnode_zonelists(pgdat);
|
|
}
|
|
|
|
/* Construct the zonelist performance cache - see further mmzone.h */
|
|
static void build_zonelist_cache(pg_data_t *pgdat)
|
|
{
|
|
struct zonelist *zonelist;
|
|
struct zonelist_cache *zlc;
|
|
struct zoneref *z;
|
|
|
|
zonelist = &pgdat->node_zonelists[0];
|
|
zonelist->zlcache_ptr = zlc = &zonelist->zlcache;
|
|
bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
|
|
for (z = zonelist->_zonerefs; z->zone; z++)
|
|
zlc->z_to_n[z - zonelist->_zonerefs] = zonelist_node_idx(z);
|
|
}
|
|
|
|
#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 zone *zone;
|
|
|
|
(void)first_zones_zonelist(node_zonelist(node, GFP_KERNEL),
|
|
gfp_zone(GFP_KERNEL),
|
|
NULL,
|
|
&zone);
|
|
return zone->node;
|
|
}
|
|
#endif
|
|
|
|
#else /* CONFIG_NUMA */
|
|
|
|
static void set_zonelist_order(void)
|
|
{
|
|
current_zonelist_order = ZONELIST_ORDER_ZONE;
|
|
}
|
|
|
|
static void build_zonelists(pg_data_t *pgdat)
|
|
{
|
|
int node, local_node;
|
|
enum zone_type j;
|
|
struct zonelist *zonelist;
|
|
|
|
local_node = pgdat->node_id;
|
|
|
|
zonelist = &pgdat->node_zonelists[0];
|
|
j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1);
|
|
|
|
/*
|
|
* 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;
|
|
j = build_zonelists_node(NODE_DATA(node), zonelist, j,
|
|
MAX_NR_ZONES - 1);
|
|
}
|
|
for (node = 0; node < local_node; node++) {
|
|
if (!node_online(node))
|
|
continue;
|
|
j = build_zonelists_node(NODE_DATA(node), zonelist, j,
|
|
MAX_NR_ZONES - 1);
|
|
}
|
|
|
|
zonelist->_zonerefs[j].zone = NULL;
|
|
zonelist->_zonerefs[j].zone_idx = 0;
|
|
}
|
|
|
|
/* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
|
|
static void build_zonelist_cache(pg_data_t *pgdat)
|
|
{
|
|
pgdat->node_zonelists[0].zlcache_ptr = NULL;
|
|
}
|
|
|
|
#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 setup_pageset(struct per_cpu_pageset *p, unsigned long batch);
|
|
static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset);
|
|
static void setup_zone_pageset(struct zone *zone);
|
|
|
|
/*
|
|
* Global mutex to protect against size modification of zonelists
|
|
* as well as to serialize pageset setup for the new populated zone.
|
|
*/
|
|
DEFINE_MUTEX(zonelists_mutex);
|
|
|
|
/* return values int ....just for stop_machine() */
|
|
static int __build_all_zonelists(void *data)
|
|
{
|
|
int nid;
|
|
int cpu;
|
|
pg_data_t *self = data;
|
|
|
|
#ifdef CONFIG_NUMA
|
|
memset(node_load, 0, sizeof(node_load));
|
|
#endif
|
|
|
|
if (self && !node_online(self->node_id)) {
|
|
build_zonelists(self);
|
|
build_zonelist_cache(self);
|
|
}
|
|
|
|
for_each_online_node(nid) {
|
|
pg_data_t *pgdat = NODE_DATA(nid);
|
|
|
|
build_zonelists(pgdat);
|
|
build_zonelist_cache(pgdat);
|
|
}
|
|
|
|
/*
|
|
* 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) {
|
|
setup_pageset(&per_cpu(boot_pageset, cpu), 0);
|
|
|
|
#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.
|
|
*/
|
|
if (cpu_online(cpu))
|
|
set_cpu_numa_mem(cpu, local_memory_node(cpu_to_node(cpu)));
|
|
#endif
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Called with zonelists_mutex held always
|
|
* unless system_state == SYSTEM_BOOTING.
|
|
*/
|
|
void __ref build_all_zonelists(pg_data_t *pgdat, struct zone *zone)
|
|
{
|
|
set_zonelist_order();
|
|
|
|
if (system_state == SYSTEM_BOOTING) {
|
|
__build_all_zonelists(NULL);
|
|
mminit_verify_zonelist();
|
|
cpuset_init_current_mems_allowed();
|
|
} else {
|
|
/* we have to stop all cpus to guarantee there is no user
|
|
of zonelist */
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
if (zone)
|
|
setup_zone_pageset(zone);
|
|
#endif
|
|
stop_machine(__build_all_zonelists, pgdat, NULL);
|
|
/* cpuset refresh routine should be here */
|
|
}
|
|
vm_total_pages = nr_free_pagecache_pages();
|
|
/*
|
|
* 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;
|
|
|
|
printk("Built %i zonelists in %s order, mobility grouping %s. "
|
|
"Total pages: %ld\n",
|
|
nr_online_nodes,
|
|
zonelist_order_name[current_zonelist_order],
|
|
page_group_by_mobility_disabled ? "off" : "on",
|
|
vm_total_pages);
|
|
#ifdef CONFIG_NUMA
|
|
printk("Policy zone: %s\n", zone_names[policy_zone]);
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Helper functions to size the waitqueue hash table.
|
|
* Essentially these want to choose hash table sizes sufficiently
|
|
* large so that collisions trying to wait on pages are rare.
|
|
* But in fact, the number of active page waitqueues on typical
|
|
* systems is ridiculously low, less than 200. So this is even
|
|
* conservative, even though it seems large.
|
|
*
|
|
* The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
|
|
* waitqueues, i.e. the size of the waitq table given the number of pages.
|
|
*/
|
|
#define PAGES_PER_WAITQUEUE 256
|
|
|
|
#ifndef CONFIG_MEMORY_HOTPLUG
|
|
static inline unsigned long wait_table_hash_nr_entries(unsigned long pages)
|
|
{
|
|
unsigned long size = 1;
|
|
|
|
pages /= PAGES_PER_WAITQUEUE;
|
|
|
|
while (size < pages)
|
|
size <<= 1;
|
|
|
|
/*
|
|
* Once we have dozens or even hundreds of threads sleeping
|
|
* on IO we've got bigger problems than wait queue collision.
|
|
* Limit the size of the wait table to a reasonable size.
|
|
*/
|
|
size = min(size, 4096UL);
|
|
|
|
return max(size, 4UL);
|
|
}
|
|
#else
|
|
/*
|
|
* A zone's size might be changed by hot-add, so it is not possible to determine
|
|
* a suitable size for its wait_table. So we use the maximum size now.
|
|
*
|
|
* The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
|
|
*
|
|
* i386 (preemption config) : 4096 x 16 = 64Kbyte.
|
|
* ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
|
|
* ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
|
|
*
|
|
* The maximum entries are prepared when a zone's memory is (512K + 256) pages
|
|
* or more by the traditional way. (See above). It equals:
|
|
*
|
|
* i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
|
|
* ia64(16K page size) : = ( 8G + 4M)byte.
|
|
* powerpc (64K page size) : = (32G +16M)byte.
|
|
*/
|
|
static inline unsigned long wait_table_hash_nr_entries(unsigned long pages)
|
|
{
|
|
return 4096UL;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* This is an integer logarithm so that shifts can be used later
|
|
* to extract the more random high bits from the multiplicative
|
|
* hash function before the remainder is taken.
|
|
*/
|
|
static inline unsigned long wait_table_bits(unsigned long size)
|
|
{
|
|
return ffz(~size);
|
|
}
|
|
|
|
#define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
|
|
|
|
/*
|
|
* Check if a pageblock contains reserved pages
|
|
*/
|
|
static int pageblock_is_reserved(unsigned long start_pfn, unsigned long end_pfn)
|
|
{
|
|
unsigned long pfn;
|
|
|
|
for (pfn = start_pfn; pfn < end_pfn; pfn++) {
|
|
if (!pfn_valid_within(pfn) || PageReserved(pfn_to_page(pfn)))
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Mark a number of pageblocks as MIGRATE_RESERVE. The number
|
|
* of blocks reserved is based on min_wmark_pages(zone). The memory within
|
|
* the reserve will tend to store contiguous free pages. Setting min_free_kbytes
|
|
* higher will lead to a bigger reserve which will get freed as contiguous
|
|
* blocks as reclaim kicks in
|
|
*/
|
|
static void setup_zone_migrate_reserve(struct zone *zone)
|
|
{
|
|
unsigned long start_pfn, pfn, end_pfn, block_end_pfn;
|
|
struct page *page;
|
|
unsigned long block_migratetype;
|
|
int reserve;
|
|
|
|
/*
|
|
* Get the start pfn, end pfn and the number of blocks to reserve
|
|
* We have to be careful to be aligned to pageblock_nr_pages to
|
|
* make sure that we always check pfn_valid for the first page in
|
|
* the block.
|
|
*/
|
|
start_pfn = zone->zone_start_pfn;
|
|
end_pfn = start_pfn + zone->spanned_pages;
|
|
start_pfn = roundup(start_pfn, pageblock_nr_pages);
|
|
reserve = roundup(min_wmark_pages(zone), pageblock_nr_pages) >>
|
|
pageblock_order;
|
|
|
|
/*
|
|
* Reserve blocks are generally in place to help high-order atomic
|
|
* allocations that are short-lived. A min_free_kbytes value that
|
|
* would result in more than 2 reserve blocks for atomic allocations
|
|
* is assumed to be in place to help anti-fragmentation for the
|
|
* future allocation of hugepages at runtime.
|
|
*/
|
|
reserve = min(2, reserve);
|
|
|
|
for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
|
|
if (!pfn_valid(pfn))
|
|
continue;
|
|
page = pfn_to_page(pfn);
|
|
|
|
/* Watch out for overlapping nodes */
|
|
if (page_to_nid(page) != zone_to_nid(zone))
|
|
continue;
|
|
|
|
block_migratetype = get_pageblock_migratetype(page);
|
|
|
|
/* Only test what is necessary when the reserves are not met */
|
|
if (reserve > 0) {
|
|
/*
|
|
* Blocks with reserved pages will never free, skip
|
|
* them.
|
|
*/
|
|
block_end_pfn = min(pfn + pageblock_nr_pages, end_pfn);
|
|
if (pageblock_is_reserved(pfn, block_end_pfn))
|
|
continue;
|
|
|
|
/* If this block is reserved, account for it */
|
|
if (block_migratetype == MIGRATE_RESERVE) {
|
|
reserve--;
|
|
continue;
|
|
}
|
|
|
|
/* Suitable for reserving if this block is movable */
|
|
if (block_migratetype == MIGRATE_MOVABLE) {
|
|
set_pageblock_migratetype(page,
|
|
MIGRATE_RESERVE);
|
|
move_freepages_block(zone, page,
|
|
MIGRATE_RESERVE);
|
|
reserve--;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If the reserve is met and this is a previous reserved block,
|
|
* take it back
|
|
*/
|
|
if (block_migratetype == MIGRATE_RESERVE) {
|
|
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
|
|
move_freepages_block(zone, page, MIGRATE_MOVABLE);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Initially all pages are reserved - free ones are freed
|
|
* up by free_all_bootmem() once the early boot process is
|
|
* done. Non-atomic initialization, single-pass.
|
|
*/
|
|
void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
|
|
unsigned long start_pfn, enum memmap_context context)
|
|
{
|
|
struct page *page;
|
|
unsigned long end_pfn = start_pfn + size;
|
|
unsigned long pfn;
|
|
struct zone *z;
|
|
|
|
if (highest_memmap_pfn < end_pfn - 1)
|
|
highest_memmap_pfn = end_pfn - 1;
|
|
|
|
z = &NODE_DATA(nid)->node_zones[zone];
|
|
for (pfn = start_pfn; pfn < end_pfn; pfn++) {
|
|
/*
|
|
* There can be holes in boot-time mem_map[]s
|
|
* handed to this function. They do not
|
|
* exist on hotplugged memory.
|
|
*/
|
|
if (context == MEMMAP_EARLY) {
|
|
if (!early_pfn_valid(pfn))
|
|
continue;
|
|
if (!early_pfn_in_nid(pfn, nid))
|
|
continue;
|
|
}
|
|
page = pfn_to_page(pfn);
|
|
set_page_links(page, zone, nid, pfn);
|
|
mminit_verify_page_links(page, zone, nid, pfn);
|
|
init_page_count(page);
|
|
reset_page_mapcount(page);
|
|
SetPageReserved(page);
|
|
/*
|
|
* 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. Later some blocks near
|
|
* the start are marked MIGRATE_RESERVE by
|
|
* setup_zone_migrate_reserve()
|
|
*
|
|
* bitmap is created for zone's valid pfn range. but memmap
|
|
* can be created for invalid pages (for alignment)
|
|
* check here not to call set_pageblock_migratetype() against
|
|
* pfn out of zone.
|
|
*/
|
|
if ((z->zone_start_pfn <= pfn)
|
|
&& (pfn < z->zone_start_pfn + z->spanned_pages)
|
|
&& !(pfn & (pageblock_nr_pages - 1)))
|
|
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
|
|
|
|
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
|
|
}
|
|
}
|
|
|
|
static void __meminit zone_init_free_lists(struct zone *zone)
|
|
{
|
|
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;
|
|
}
|
|
}
|
|
|
|
#ifndef __HAVE_ARCH_MEMMAP_INIT
|
|
#define memmap_init(size, nid, zone, start_pfn) \
|
|
memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
|
|
#endif
|
|
|
|
static int __meminit 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. But no more than 1/2 of a meg.
|
|
*
|
|
* OK, so we don't know how big the cache is. So guess.
|
|
*/
|
|
batch = zone->present_pages / 1024;
|
|
if (batch * PAGE_SIZE > 512 * 1024)
|
|
batch = (512 * 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
|
|
}
|
|
|
|
static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
|
|
{
|
|
struct per_cpu_pages *pcp;
|
|
int migratetype;
|
|
|
|
memset(p, 0, sizeof(*p));
|
|
|
|
pcp = &p->pcp;
|
|
pcp->count = 0;
|
|
pcp->high = 6 * batch;
|
|
pcp->batch = max(1UL, 1 * batch);
|
|
for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++)
|
|
INIT_LIST_HEAD(&pcp->lists[migratetype]);
|
|
}
|
|
|
|
/*
|
|
* setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
|
|
* to the value high for the pageset p.
|
|
*/
|
|
|
|
static void setup_pagelist_highmark(struct per_cpu_pageset *p,
|
|
unsigned long high)
|
|
{
|
|
struct per_cpu_pages *pcp;
|
|
|
|
pcp = &p->pcp;
|
|
pcp->high = high;
|
|
pcp->batch = max(1UL, high/4);
|
|
if ((high/4) > (PAGE_SHIFT * 8))
|
|
pcp->batch = PAGE_SHIFT * 8;
|
|
}
|
|
|
|
static void __meminit setup_zone_pageset(struct zone *zone)
|
|
{
|
|
int cpu;
|
|
|
|
zone->pageset = alloc_percpu(struct per_cpu_pageset);
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu);
|
|
|
|
setup_pageset(pcp, zone_batchsize(zone));
|
|
|
|
if (percpu_pagelist_fraction)
|
|
setup_pagelist_highmark(pcp,
|
|
(zone->present_pages /
|
|
percpu_pagelist_fraction));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Allocate per cpu pagesets and initialize them.
|
|
* Before this call only boot pagesets were available.
|
|
*/
|
|
void __init setup_per_cpu_pageset(void)
|
|
{
|
|
struct zone *zone;
|
|
|
|
for_each_populated_zone(zone)
|
|
setup_zone_pageset(zone);
|
|
}
|
|
|
|
static noinline __init_refok
|
|
int zone_wait_table_init(struct zone *zone, unsigned long zone_size_pages)
|
|
{
|
|
int i;
|
|
struct pglist_data *pgdat = zone->zone_pgdat;
|
|
size_t alloc_size;
|
|
|
|
/*
|
|
* The per-page waitqueue mechanism uses hashed waitqueues
|
|
* per zone.
|
|
*/
|
|
zone->wait_table_hash_nr_entries =
|
|
wait_table_hash_nr_entries(zone_size_pages);
|
|
zone->wait_table_bits =
|
|
wait_table_bits(zone->wait_table_hash_nr_entries);
|
|
alloc_size = zone->wait_table_hash_nr_entries
|
|
* sizeof(wait_queue_head_t);
|
|
|
|
if (!slab_is_available()) {
|
|
zone->wait_table = (wait_queue_head_t *)
|
|
alloc_bootmem_node_nopanic(pgdat, alloc_size);
|
|
} else {
|
|
/*
|
|
* This case means that a zone whose size was 0 gets new memory
|
|
* via memory hot-add.
|
|
* But it may be the case that a new node was hot-added. In
|
|
* this case vmalloc() will not be able to use this new node's
|
|
* memory - this wait_table must be initialized to use this new
|
|
* node itself as well.
|
|
* To use this new node's memory, further consideration will be
|
|
* necessary.
|
|
*/
|
|
zone->wait_table = vmalloc(alloc_size);
|
|
}
|
|
if (!zone->wait_table)
|
|
return -ENOMEM;
|
|
|
|
for(i = 0; i < zone->wait_table_hash_nr_entries; ++i)
|
|
init_waitqueue_head(zone->wait_table + i);
|
|
|
|
return 0;
|
|
}
|
|
|
|
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;
|
|
|
|
if (zone->present_pages)
|
|
printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%u\n",
|
|
zone->name, zone->present_pages,
|
|
zone_batchsize(zone));
|
|
}
|
|
|
|
int __meminit init_currently_empty_zone(struct zone *zone,
|
|
unsigned long zone_start_pfn,
|
|
unsigned long size,
|
|
enum memmap_context context)
|
|
{
|
|
struct pglist_data *pgdat = zone->zone_pgdat;
|
|
int ret;
|
|
ret = zone_wait_table_init(zone, size);
|
|
if (ret)
|
|
return ret;
|
|
pgdat->nr_zones = zone_idx(zone) + 1;
|
|
|
|
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);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
|
|
#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
|
|
/*
|
|
* Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
|
|
* Architectures may implement their own version but if add_active_range()
|
|
* was used and there are no special requirements, this is a convenient
|
|
* alternative
|
|
*/
|
|
int __meminit __early_pfn_to_nid(unsigned long pfn)
|
|
{
|
|
unsigned long start_pfn, end_pfn;
|
|
int i, nid;
|
|
|
|
for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid)
|
|
if (start_pfn <= pfn && pfn < end_pfn)
|
|
return nid;
|
|
/* This is a memory hole */
|
|
return -1;
|
|
}
|
|
#endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
|
|
|
|
int __meminit early_pfn_to_nid(unsigned long pfn)
|
|
{
|
|
int nid;
|
|
|
|
nid = __early_pfn_to_nid(pfn);
|
|
if (nid >= 0)
|
|
return nid;
|
|
/* just returns 0 */
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_NODES_SPAN_OTHER_NODES
|
|
bool __meminit early_pfn_in_nid(unsigned long pfn, int node)
|
|
{
|
|
int nid;
|
|
|
|
nid = __early_pfn_to_nid(pfn);
|
|
if (nid >= 0 && nid != node)
|
|
return false;
|
|
return true;
|
|
}
|
|
#endif
|
|
|
|
/**
|
|
* free_bootmem_with_active_regions - Call free_bootmem_node for each active range
|
|
* @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
|
|
* @max_low_pfn: The highest PFN that will be passed to free_bootmem_node
|
|
*
|
|
* If an architecture guarantees that all ranges registered with
|
|
* add_active_ranges() contain no holes and may be freed, this
|
|
* this function may be used instead of calling free_bootmem() manually.
|
|
*/
|
|
void __init free_bootmem_with_active_regions(int nid, unsigned long max_low_pfn)
|
|
{
|
|
unsigned long start_pfn, end_pfn;
|
|
int i, this_nid;
|
|
|
|
for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid) {
|
|
start_pfn = min(start_pfn, max_low_pfn);
|
|
end_pfn = min(end_pfn, max_low_pfn);
|
|
|
|
if (start_pfn < end_pfn)
|
|
free_bootmem_node(NODE_DATA(this_nid),
|
|
PFN_PHYS(start_pfn),
|
|
(end_pfn - start_pfn) << PAGE_SHIFT);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* sparse_memory_present_with_active_regions - Call memory_present for each active range
|
|
* @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
|
|
*
|
|
* If an architecture guarantees that all ranges registered with
|
|
* add_active_ranges() contain no holes and may be freed, this
|
|
* function may be used instead of calling memory_present() manually.
|
|
*/
|
|
void __init sparse_memory_present_with_active_regions(int nid)
|
|
{
|
|
unsigned long start_pfn, end_pfn;
|
|
int i, this_nid;
|
|
|
|
for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid)
|
|
memory_present(this_nid, start_pfn, end_pfn);
|
|
}
|
|
|
|
/**
|
|
* 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 an arch calling add_active_range(). If called for a node
|
|
* with no available memory, a warning is printed and the start and end
|
|
* PFNs will be 0.
|
|
*/
|
|
void __meminit 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 __meminit 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 (*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 __meminit zone_spanned_pages_in_node(int nid,
|
|
unsigned long zone_type,
|
|
unsigned long *ignored)
|
|
{
|
|
unsigned long node_start_pfn, node_end_pfn;
|
|
unsigned long zone_start_pfn, zone_end_pfn;
|
|
|
|
/* Get the start and end of the node and zone */
|
|
get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn);
|
|
zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type];
|
|
zone_end_pfn = arch_zone_highest_possible_pfn[zone_type];
|
|
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 __meminit __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
|
|
*
|
|
* It returns 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 __meminit zone_absent_pages_in_node(int nid,
|
|
unsigned long zone_type,
|
|
unsigned long *ignored)
|
|
{
|
|
unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type];
|
|
unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type];
|
|
unsigned long node_start_pfn, node_end_pfn;
|
|
unsigned long zone_start_pfn, zone_end_pfn;
|
|
|
|
get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn);
|
|
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);
|
|
return __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
|
|
}
|
|
|
|
#else /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
|
|
static inline unsigned long __meminit zone_spanned_pages_in_node(int nid,
|
|
unsigned long zone_type,
|
|
unsigned long *zones_size)
|
|
{
|
|
return zones_size[zone_type];
|
|
}
|
|
|
|
static inline unsigned long __meminit zone_absent_pages_in_node(int nid,
|
|
unsigned long zone_type,
|
|
unsigned long *zholes_size)
|
|
{
|
|
if (!zholes_size)
|
|
return 0;
|
|
|
|
return zholes_size[zone_type];
|
|
}
|
|
|
|
#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
|
|
|
|
static void __meminit calculate_node_totalpages(struct pglist_data *pgdat,
|
|
unsigned long *zones_size, unsigned long *zholes_size)
|
|
{
|
|
unsigned long realtotalpages, totalpages = 0;
|
|
enum zone_type i;
|
|
|
|
for (i = 0; i < MAX_NR_ZONES; i++)
|
|
totalpages += zone_spanned_pages_in_node(pgdat->node_id, i,
|
|
zones_size);
|
|
pgdat->node_spanned_pages = totalpages;
|
|
|
|
realtotalpages = totalpages;
|
|
for (i = 0; i < MAX_NR_ZONES; i++)
|
|
realtotalpages -=
|
|
zone_absent_pages_in_node(pgdat->node_id, i,
|
|
zholes_size);
|
|
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 zonesize)
|
|
{
|
|
unsigned long usemapsize;
|
|
|
|
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 __init setup_usemap(struct pglist_data *pgdat,
|
|
struct zone *zone, unsigned long zonesize)
|
|
{
|
|
unsigned long usemapsize = usemap_size(zonesize);
|
|
zone->pageblock_flags = NULL;
|
|
if (usemapsize)
|
|
zone->pageblock_flags = alloc_bootmem_node_nopanic(pgdat,
|
|
usemapsize);
|
|
}
|
|
#else
|
|
static inline void setup_usemap(struct pglist_data *pgdat,
|
|
struct zone *zone, unsigned long zonesize) {}
|
|
#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 */
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
static void __paginginit free_area_init_core(struct pglist_data *pgdat,
|
|
unsigned long *zones_size, unsigned long *zholes_size)
|
|
{
|
|
enum zone_type j;
|
|
int nid = pgdat->node_id;
|
|
unsigned long zone_start_pfn = pgdat->node_start_pfn;
|
|
int ret;
|
|
|
|
pgdat_resize_init(pgdat);
|
|
init_waitqueue_head(&pgdat->kswapd_wait);
|
|
init_waitqueue_head(&pgdat->pfmemalloc_wait);
|
|
pgdat_page_cgroup_init(pgdat);
|
|
|
|
for (j = 0; j < MAX_NR_ZONES; j++) {
|
|
struct zone *zone = pgdat->node_zones + j;
|
|
unsigned long size, realsize, memmap_pages;
|
|
|
|
size = zone_spanned_pages_in_node(nid, j, zones_size);
|
|
realsize = size - zone_absent_pages_in_node(nid, j,
|
|
zholes_size);
|
|
|
|
/*
|
|
* Adjust realsize 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 =
|
|
PAGE_ALIGN(size * sizeof(struct page)) >> PAGE_SHIFT;
|
|
if (realsize >= memmap_pages) {
|
|
realsize -= memmap_pages;
|
|
if (memmap_pages)
|
|
printk(KERN_DEBUG
|
|
" %s zone: %lu pages used for memmap\n",
|
|
zone_names[j], memmap_pages);
|
|
} else
|
|
printk(KERN_WARNING
|
|
" %s zone: %lu pages exceeds realsize %lu\n",
|
|
zone_names[j], memmap_pages, realsize);
|
|
|
|
/* Account for reserved pages */
|
|
if (j == 0 && realsize > dma_reserve) {
|
|
realsize -= dma_reserve;
|
|
printk(KERN_DEBUG " %s zone: %lu pages reserved\n",
|
|
zone_names[0], dma_reserve);
|
|
}
|
|
|
|
if (!is_highmem_idx(j))
|
|
nr_kernel_pages += realsize;
|
|
nr_all_pages += realsize;
|
|
|
|
zone->spanned_pages = size;
|
|
zone->present_pages = realsize;
|
|
#if defined CONFIG_COMPACTION || defined CONFIG_CMA
|
|
zone->compact_cached_free_pfn = zone->zone_start_pfn +
|
|
zone->spanned_pages;
|
|
zone->compact_cached_free_pfn &= ~(pageblock_nr_pages-1);
|
|
#endif
|
|
#ifdef CONFIG_NUMA
|
|
zone->node = nid;
|
|
zone->min_unmapped_pages = (realsize*sysctl_min_unmapped_ratio)
|
|
/ 100;
|
|
zone->min_slab_pages = (realsize * sysctl_min_slab_ratio) / 100;
|
|
#endif
|
|
zone->name = zone_names[j];
|
|
spin_lock_init(&zone->lock);
|
|
spin_lock_init(&zone->lru_lock);
|
|
zone_seqlock_init(zone);
|
|
zone->zone_pgdat = pgdat;
|
|
|
|
zone_pcp_init(zone);
|
|
lruvec_init(&zone->lruvec, zone);
|
|
if (!size)
|
|
continue;
|
|
|
|
set_pageblock_order();
|
|
setup_usemap(pgdat, zone, size);
|
|
ret = init_currently_empty_zone(zone, zone_start_pfn,
|
|
size, MEMMAP_EARLY);
|
|
BUG_ON(ret);
|
|
memmap_init(size, nid, j, zone_start_pfn);
|
|
zone_start_pfn += size;
|
|
}
|
|
}
|
|
|
|
static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat)
|
|
{
|
|
/* Skip empty nodes */
|
|
if (!pgdat->node_spanned_pages)
|
|
return;
|
|
|
|
#ifdef CONFIG_FLAT_NODE_MEM_MAP
|
|
/* ia64 gets its own node_mem_map, before this, without bootmem */
|
|
if (!pgdat->node_mem_map) {
|
|
unsigned long size, start, 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.
|
|
*/
|
|
start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
|
|
end = pgdat->node_start_pfn + pgdat->node_spanned_pages;
|
|
end = ALIGN(end, MAX_ORDER_NR_PAGES);
|
|
size = (end - start) * sizeof(struct page);
|
|
map = alloc_remap(pgdat->node_id, size);
|
|
if (!map)
|
|
map = alloc_bootmem_node_nopanic(pgdat, size);
|
|
pgdat->node_mem_map = map + (pgdat->node_start_pfn - start);
|
|
}
|
|
#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;
|
|
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
|
|
if (page_to_pfn(mem_map) != pgdat->node_start_pfn)
|
|
mem_map -= (pgdat->node_start_pfn - ARCH_PFN_OFFSET);
|
|
#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
|
|
}
|
|
#endif
|
|
#endif /* CONFIG_FLAT_NODE_MEM_MAP */
|
|
}
|
|
|
|
void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
|
|
unsigned long node_start_pfn, unsigned long *zholes_size)
|
|
{
|
|
pg_data_t *pgdat = NODE_DATA(nid);
|
|
|
|
/* pg_data_t should be reset to zero when it's allocated */
|
|
WARN_ON(pgdat->nr_zones || pgdat->node_start_pfn || pgdat->classzone_idx);
|
|
|
|
pgdat->node_id = nid;
|
|
pgdat->node_start_pfn = node_start_pfn;
|
|
calculate_node_totalpages(pgdat, zones_size, zholes_size);
|
|
|
|
alloc_node_mem_map(pgdat);
|
|
#ifdef CONFIG_FLAT_NODE_MEM_MAP
|
|
printk(KERN_DEBUG "free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n",
|
|
nid, (unsigned long)pgdat,
|
|
(unsigned long)pgdat->node_mem_map);
|
|
#endif
|
|
|
|
free_area_init_core(pgdat, zones_size, zholes_size);
|
|
}
|
|
|
|
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
|
|
|
|
#if MAX_NUMNODES > 1
|
|
/*
|
|
* Figure out the number of possible node ids.
|
|
*/
|
|
static void __init setup_nr_node_ids(void)
|
|
{
|
|
unsigned int node;
|
|
unsigned int highest = 0;
|
|
|
|
for_each_node_mask(node, node_possible_map)
|
|
highest = node;
|
|
nr_node_ids = highest + 1;
|
|
}
|
|
#else
|
|
static inline void setup_nr_node_ids(void)
|
|
{
|
|
}
|
|
#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.
|
|
*
|
|
* Returns 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 = -1;
|
|
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 the lowest pfn for a node */
|
|
static unsigned long __init find_min_pfn_for_node(int nid)
|
|
{
|
|
unsigned long min_pfn = ULONG_MAX;
|
|
unsigned long start_pfn;
|
|
int i;
|
|
|
|
for_each_mem_pfn_range(i, nid, &start_pfn, NULL, NULL)
|
|
min_pfn = min(min_pfn, start_pfn);
|
|
|
|
if (min_pfn == ULONG_MAX) {
|
|
printk(KERN_WARNING
|
|
"Could not find start_pfn for node %d\n", nid);
|
|
return 0;
|
|
}
|
|
|
|
return min_pfn;
|
|
}
|
|
|
|
/**
|
|
* find_min_pfn_with_active_regions - Find the minimum PFN registered
|
|
*
|
|
* It returns the minimum PFN based on information provided via
|
|
* add_active_range().
|
|
*/
|
|
unsigned long __init find_min_pfn_with_active_regions(void)
|
|
{
|
|
return find_min_pfn_for_node(MAX_NUMNODES);
|
|
}
|
|
|
|
/*
|
|
* early_calculate_totalpages()
|
|
* Sum pages in active regions for movable zone.
|
|
* Populate N_HIGH_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_HIGH_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_HIGH_MEMORY];
|
|
unsigned long totalpages = early_calculate_totalpages();
|
|
int usable_nodes = nodes_weight(node_states[N_HIGH_MEMORY]);
|
|
|
|
/*
|
|
* 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);
|
|
corepages = totalpages - required_movablecore;
|
|
|
|
required_kernelcore = max(required_kernelcore, corepages);
|
|
}
|
|
|
|
/* If kernelcore was not specified, there is no ZONE_MOVABLE */
|
|
if (!required_kernelcore)
|
|
goto out;
|
|
|
|
/* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
|
|
find_usable_zone_for_movable();
|
|
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_HIGH_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
|
|
* satisified
|
|
*/
|
|
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
|
|
* satisified
|
|
*/
|
|
usable_nodes--;
|
|
if (usable_nodes && required_kernelcore > usable_nodes)
|
|
goto restart;
|
|
|
|
/* 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_HIGH_MEMORY] = saved_node_state;
|
|
}
|
|
|
|
/* Any regular memory on that node ? */
|
|
static void __init check_for_regular_memory(pg_data_t *pgdat)
|
|
{
|
|
#ifdef CONFIG_HIGHMEM
|
|
enum zone_type zone_type;
|
|
|
|
for (zone_type = 0; zone_type <= ZONE_NORMAL; zone_type++) {
|
|
struct zone *zone = &pgdat->node_zones[zone_type];
|
|
if (zone->present_pages) {
|
|
node_set_state(zone_to_nid(zone), N_NORMAL_MEMORY);
|
|
break;
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* free_area_init_nodes - 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 add_active_range(), 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_nodes(unsigned long *max_zone_pfn)
|
|
{
|
|
unsigned long start_pfn, end_pfn;
|
|
int i, nid;
|
|
|
|
/* 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));
|
|
arch_zone_lowest_possible_pfn[0] = find_min_pfn_with_active_regions();
|
|
arch_zone_highest_possible_pfn[0] = max_zone_pfn[0];
|
|
for (i = 1; i < MAX_NR_ZONES; i++) {
|
|
if (i == ZONE_MOVABLE)
|
|
continue;
|
|
arch_zone_lowest_possible_pfn[i] =
|
|
arch_zone_highest_possible_pfn[i-1];
|
|
arch_zone_highest_possible_pfn[i] =
|
|
max(max_zone_pfn[i], arch_zone_lowest_possible_pfn[i]);
|
|
}
|
|
arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0;
|
|
arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0;
|
|
|
|
/* 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 */
|
|
printk("Zone ranges:\n");
|
|
for (i = 0; i < MAX_NR_ZONES; i++) {
|
|
if (i == ZONE_MOVABLE)
|
|
continue;
|
|
printk(KERN_CONT " %-8s ", zone_names[i]);
|
|
if (arch_zone_lowest_possible_pfn[i] ==
|
|
arch_zone_highest_possible_pfn[i])
|
|
printk(KERN_CONT "empty\n");
|
|
else
|
|
printk(KERN_CONT "[mem %0#10lx-%0#10lx]\n",
|
|
arch_zone_lowest_possible_pfn[i] << PAGE_SHIFT,
|
|
(arch_zone_highest_possible_pfn[i]
|
|
<< PAGE_SHIFT) - 1);
|
|
}
|
|
|
|
/* Print out the PFNs ZONE_MOVABLE begins at in each node */
|
|
printk("Movable zone start for each node\n");
|
|
for (i = 0; i < MAX_NUMNODES; i++) {
|
|
if (zone_movable_pfn[i])
|
|
printk(" Node %d: %#010lx\n", i,
|
|
zone_movable_pfn[i] << PAGE_SHIFT);
|
|
}
|
|
|
|
/* Print out the early_node_map[] */
|
|
printk("Early memory node ranges\n");
|
|
for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid)
|
|
printk(" node %3d: [mem %#010lx-%#010lx]\n", nid,
|
|
start_pfn << PAGE_SHIFT, (end_pfn << PAGE_SHIFT) - 1);
|
|
|
|
/* 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, NULL,
|
|
find_min_pfn_for_node(nid), NULL);
|
|
|
|
/* Any memory on that node */
|
|
if (pgdat->node_present_pages)
|
|
node_set_state(nid, N_HIGH_MEMORY);
|
|
check_for_regular_memory(pgdat);
|
|
}
|
|
}
|
|
|
|
static int __init cmdline_parse_core(char *p, unsigned long *core)
|
|
{
|
|
unsigned long long coremem;
|
|
if (!p)
|
|
return -EINVAL;
|
|
|
|
coremem = memparse(p, &p);
|
|
*core = coremem >> PAGE_SHIFT;
|
|
|
|
/* Paranoid check that UL is enough for the coremem value */
|
|
WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX);
|
|
|
|
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)
|
|
{
|
|
return cmdline_parse_core(p, &required_kernelcore);
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
}
|
|
|
|
early_param("kernelcore", cmdline_parse_kernelcore);
|
|
early_param("movablecore", cmdline_parse_movablecore);
|
|
|
|
#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
|
|
|
|
/**
|
|
* 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 present_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;
|
|
}
|
|
|
|
void __init free_area_init(unsigned long *zones_size)
|
|
{
|
|
free_area_init_node(0, zones_size,
|
|
__pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL);
|
|
}
|
|
|
|
static int page_alloc_cpu_notify(struct notifier_block *self,
|
|
unsigned long action, void *hcpu)
|
|
{
|
|
int cpu = (unsigned long)hcpu;
|
|
|
|
if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
|
|
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.
|
|
*/
|
|
refresh_cpu_vm_stats(cpu);
|
|
}
|
|
return NOTIFY_OK;
|
|
}
|
|
|
|
void __init page_alloc_init(void)
|
|
{
|
|
hotcpu_notifier(page_alloc_cpu_notify, 0);
|
|
}
|
|
|
|
/*
|
|
* calculate_totalreserve_pages - called when sysctl_lower_zone_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) {
|
|
for (i = 0; i < MAX_NR_ZONES; i++) {
|
|
struct zone *zone = pgdat->node_zones + i;
|
|
unsigned long max = 0;
|
|
|
|
/* 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 > zone->present_pages)
|
|
max = zone->present_pages;
|
|
reserve_pages += max;
|
|
/*
|
|
* Lowmem reserves are not available to
|
|
* GFP_HIGHUSER page cache allocations and
|
|
* kswapd tries to balance zones to their high
|
|
* watermark. As a result, neither should be
|
|
* regarded as dirtyable memory, to prevent a
|
|
* situation where reclaim has to clean pages
|
|
* in order to balance the zones.
|
|
*/
|
|
zone->dirty_balance_reserve = max;
|
|
}
|
|
}
|
|
dirty_balance_reserve = reserve_pages;
|
|
totalreserve_pages = reserve_pages;
|
|
}
|
|
|
|
/*
|
|
* setup_per_zone_lowmem_reserve - called whenever
|
|
* sysctl_lower_zone_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 j, idx;
|
|
|
|
for_each_online_pgdat(pgdat) {
|
|
for (j = 0; j < MAX_NR_ZONES; j++) {
|
|
struct zone *zone = pgdat->node_zones + j;
|
|
unsigned long present_pages = zone->present_pages;
|
|
|
|
zone->lowmem_reserve[j] = 0;
|
|
|
|
idx = j;
|
|
while (idx) {
|
|
struct zone *lower_zone;
|
|
|
|
idx--;
|
|
|
|
if (sysctl_lowmem_reserve_ratio[idx] < 1)
|
|
sysctl_lowmem_reserve_ratio[idx] = 1;
|
|
|
|
lower_zone = pgdat->node_zones + idx;
|
|
lower_zone->lowmem_reserve[j] = present_pages /
|
|
sysctl_lowmem_reserve_ratio[idx];
|
|
present_pages += lower_zone->present_pages;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* 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->present_pages;
|
|
}
|
|
|
|
for_each_zone(zone) {
|
|
u64 tmp;
|
|
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
tmp = (u64)pages_min * zone->present_pages;
|
|
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 controls asynch page reclaim, and so should
|
|
* not be capped for highmem.
|
|
*/
|
|
int min_pages;
|
|
|
|
min_pages = zone->present_pages / 1024;
|
|
if (min_pages < SWAP_CLUSTER_MAX)
|
|
min_pages = SWAP_CLUSTER_MAX;
|
|
if (min_pages > 128)
|
|
min_pages = 128;
|
|
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;
|
|
}
|
|
|
|
zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2);
|
|
zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1);
|
|
|
|
zone->watermark[WMARK_MIN] += cma_wmark_pages(zone);
|
|
zone->watermark[WMARK_LOW] += cma_wmark_pages(zone);
|
|
zone->watermark[WMARK_HIGH] += cma_wmark_pages(zone);
|
|
|
|
setup_zone_migrate_reserve(zone);
|
|
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)
|
|
{
|
|
mutex_lock(&zonelists_mutex);
|
|
__setup_per_zone_wmarks();
|
|
mutex_unlock(&zonelists_mutex);
|
|
}
|
|
|
|
/*
|
|
* The inactive anon list should be small enough that the VM never has to
|
|
* do too much work, but large enough that each inactive page has a chance
|
|
* to be referenced again before it is swapped out.
|
|
*
|
|
* The inactive_anon ratio is the target ratio of ACTIVE_ANON to
|
|
* INACTIVE_ANON pages on this zone's LRU, maintained by the
|
|
* pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of
|
|
* the anonymous pages are kept on the inactive list.
|
|
*
|
|
* total target max
|
|
* memory ratio inactive anon
|
|
* -------------------------------------
|
|
* 10MB 1 5MB
|
|
* 100MB 1 50MB
|
|
* 1GB 3 250MB
|
|
* 10GB 10 0.9GB
|
|
* 100GB 31 3GB
|
|
* 1TB 101 10GB
|
|
* 10TB 320 32GB
|
|
*/
|
|
static void __meminit calculate_zone_inactive_ratio(struct zone *zone)
|
|
{
|
|
unsigned int gb, ratio;
|
|
|
|
/* Zone size in gigabytes */
|
|
gb = zone->present_pages >> (30 - PAGE_SHIFT);
|
|
if (gb)
|
|
ratio = int_sqrt(10 * gb);
|
|
else
|
|
ratio = 1;
|
|
|
|
zone->inactive_ratio = ratio;
|
|
}
|
|
|
|
static void __meminit setup_per_zone_inactive_ratio(void)
|
|
{
|
|
struct zone *zone;
|
|
|
|
for_each_zone(zone)
|
|
calculate_zone_inactive_ratio(zone);
|
|
}
|
|
|
|
/*
|
|
* Initialise min_free_kbytes.
|
|
*
|
|
* For small machines we want it small (128k min). For large machines
|
|
* we want it large (64MB 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;
|
|
|
|
lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10);
|
|
|
|
min_free_kbytes = int_sqrt(lowmem_kbytes * 16);
|
|
if (min_free_kbytes < 128)
|
|
min_free_kbytes = 128;
|
|
if (min_free_kbytes > 65536)
|
|
min_free_kbytes = 65536;
|
|
setup_per_zone_wmarks();
|
|
refresh_zone_stat_thresholds();
|
|
setup_per_zone_lowmem_reserve();
|
|
setup_per_zone_inactive_ratio();
|
|
return 0;
|
|
}
|
|
module_init(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(ctl_table *table, int write,
|
|
void __user *buffer, size_t *length, loff_t *ppos)
|
|
{
|
|
proc_dointvec(table, write, buffer, length, ppos);
|
|
if (write)
|
|
setup_per_zone_wmarks();
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA
|
|
int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table *table, int write,
|
|
void __user *buffer, size_t *length, loff_t *ppos)
|
|
{
|
|
struct zone *zone;
|
|
int rc;
|
|
|
|
rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
|
|
if (rc)
|
|
return rc;
|
|
|
|
for_each_zone(zone)
|
|
zone->min_unmapped_pages = (zone->present_pages *
|
|
sysctl_min_unmapped_ratio) / 100;
|
|
return 0;
|
|
}
|
|
|
|
int sysctl_min_slab_ratio_sysctl_handler(ctl_table *table, int write,
|
|
void __user *buffer, size_t *length, loff_t *ppos)
|
|
{
|
|
struct zone *zone;
|
|
int rc;
|
|
|
|
rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
|
|
if (rc)
|
|
return rc;
|
|
|
|
for_each_zone(zone)
|
|
zone->min_slab_pages = (zone->present_pages *
|
|
sysctl_min_slab_ratio) / 100;
|
|
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(ctl_table *table, int write,
|
|
void __user *buffer, size_t *length, loff_t *ppos)
|
|
{
|
|
proc_dointvec_minmax(table, write, buffer, length, ppos);
|
|
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(ctl_table *table, int write,
|
|
void __user *buffer, size_t *length, loff_t *ppos)
|
|
{
|
|
struct zone *zone;
|
|
unsigned int cpu;
|
|
int ret;
|
|
|
|
ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
|
|
if (!write || (ret < 0))
|
|
return ret;
|
|
for_each_populated_zone(zone) {
|
|
for_each_possible_cpu(cpu) {
|
|
unsigned long high;
|
|
high = zone->present_pages / percpu_pagelist_fraction;
|
|
setup_pagelist_highmark(
|
|
per_cpu_ptr(zone->pageset, cpu), high);
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int hashdist = HASHDIST_DEFAULT;
|
|
|
|
#ifdef CONFIG_NUMA
|
|
static int __init set_hashdist(char *str)
|
|
{
|
|
if (!str)
|
|
return 0;
|
|
hashdist = simple_strtoul(str, &str, 0);
|
|
return 1;
|
|
}
|
|
__setup("hashdist=", set_hashdist);
|
|
#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;
|
|
|
|
/* allow the kernel cmdline to have a say */
|
|
if (!numentries) {
|
|
/* round applicable memory size up to nearest megabyte */
|
|
numentries = nr_kernel_pages;
|
|
numentries += (1UL << (20 - PAGE_SHIFT)) - 1;
|
|
numentries >>= 20 - PAGE_SHIFT;
|
|
numentries <<= 20 - PAGE_SHIFT;
|
|
|
|
/* 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);
|
|
|
|
do {
|
|
size = bucketsize << log2qty;
|
|
if (flags & HASH_EARLY)
|
|
table = alloc_bootmem_nopanic(size);
|
|
else if (hashdist)
|
|
table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL);
|
|
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
|
|
*/
|
|
if (get_order(size) < MAX_ORDER) {
|
|
table = alloc_pages_exact(size, GFP_ATOMIC);
|
|
kmemleak_alloc(table, size, 1, GFP_ATOMIC);
|
|
}
|
|
}
|
|
} while (!table && size > PAGE_SIZE && --log2qty);
|
|
|
|
if (!table)
|
|
panic("Failed to allocate %s hash table\n", tablename);
|
|
|
|
printk(KERN_INFO "%s hash table entries: %ld (order: %d, %lu bytes)\n",
|
|
tablename,
|
|
(1UL << log2qty),
|
|
ilog2(size) - PAGE_SHIFT,
|
|
size);
|
|
|
|
if (_hash_shift)
|
|
*_hash_shift = log2qty;
|
|
if (_hash_mask)
|
|
*_hash_mask = (1 << log2qty) - 1;
|
|
|
|
return table;
|
|
}
|
|
|
|
/* Return a pointer to the bitmap storing bits affecting a block of pages */
|
|
static inline unsigned long *get_pageblock_bitmap(struct zone *zone,
|
|
unsigned long pfn)
|
|
{
|
|
#ifdef CONFIG_SPARSEMEM
|
|
return __pfn_to_section(pfn)->pageblock_flags;
|
|
#else
|
|
return zone->pageblock_flags;
|
|
#endif /* CONFIG_SPARSEMEM */
|
|
}
|
|
|
|
static inline int pfn_to_bitidx(struct zone *zone, unsigned long pfn)
|
|
{
|
|
#ifdef CONFIG_SPARSEMEM
|
|
pfn &= (PAGES_PER_SECTION-1);
|
|
return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
|
|
#else
|
|
pfn = pfn - zone->zone_start_pfn;
|
|
return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
|
|
#endif /* CONFIG_SPARSEMEM */
|
|
}
|
|
|
|
/**
|
|
* get_pageblock_flags_group - Return the requested group of flags for the pageblock_nr_pages block of pages
|
|
* @page: The page within the block of interest
|
|
* @start_bitidx: The first bit of interest to retrieve
|
|
* @end_bitidx: The last bit of interest
|
|
* returns pageblock_bits flags
|
|
*/
|
|
unsigned long get_pageblock_flags_group(struct page *page,
|
|
int start_bitidx, int end_bitidx)
|
|
{
|
|
struct zone *zone;
|
|
unsigned long *bitmap;
|
|
unsigned long pfn, bitidx;
|
|
unsigned long flags = 0;
|
|
unsigned long value = 1;
|
|
|
|
zone = page_zone(page);
|
|
pfn = page_to_pfn(page);
|
|
bitmap = get_pageblock_bitmap(zone, pfn);
|
|
bitidx = pfn_to_bitidx(zone, pfn);
|
|
|
|
for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
|
|
if (test_bit(bitidx + start_bitidx, bitmap))
|
|
flags |= value;
|
|
|
|
return flags;
|
|
}
|
|
|
|
/**
|
|
* set_pageblock_flags_group - Set the requested group of flags for a pageblock_nr_pages block of pages
|
|
* @page: The page within the block of interest
|
|
* @start_bitidx: The first bit of interest
|
|
* @end_bitidx: The last bit of interest
|
|
* @flags: The flags to set
|
|
*/
|
|
void set_pageblock_flags_group(struct page *page, unsigned long flags,
|
|
int start_bitidx, int end_bitidx)
|
|
{
|
|
struct zone *zone;
|
|
unsigned long *bitmap;
|
|
unsigned long pfn, bitidx;
|
|
unsigned long value = 1;
|
|
|
|
zone = page_zone(page);
|
|
pfn = page_to_pfn(page);
|
|
bitmap = get_pageblock_bitmap(zone, pfn);
|
|
bitidx = pfn_to_bitidx(zone, pfn);
|
|
VM_BUG_ON(pfn < zone->zone_start_pfn);
|
|
VM_BUG_ON(pfn >= zone->zone_start_pfn + zone->spanned_pages);
|
|
|
|
for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
|
|
if (flags & value)
|
|
__set_bit(bitidx + start_bitidx, bitmap);
|
|
else
|
|
__clear_bit(bitidx + start_bitidx, bitmap);
|
|
}
|
|
|
|
/*
|
|
* This function checks whether pageblock includes unmovable pages or not.
|
|
* If @count is not zero, it is okay to include less @count unmovable pages
|
|
*
|
|
* PageLRU check wihtout isolation or lru_lock could race so that
|
|
* MIGRATE_MOVABLE block might include unmovable pages. It means you can't
|
|
* expect this function should be exact.
|
|
*/
|
|
bool has_unmovable_pages(struct zone *zone, struct page *page, int count)
|
|
{
|
|
unsigned long pfn, iter, found;
|
|
int mt;
|
|
|
|
/*
|
|
* For avoiding noise data, lru_add_drain_all() should be called
|
|
* If ZONE_MOVABLE, the zone never contains unmovable pages
|
|
*/
|
|
if (zone_idx(zone) == ZONE_MOVABLE)
|
|
return false;
|
|
mt = get_pageblock_migratetype(page);
|
|
if (mt == MIGRATE_MOVABLE || is_migrate_cma(mt))
|
|
return false;
|
|
|
|
pfn = page_to_pfn(page);
|
|
for (found = 0, iter = 0; iter < pageblock_nr_pages; iter++) {
|
|
unsigned long check = pfn + iter;
|
|
|
|
if (!pfn_valid_within(check))
|
|
continue;
|
|
|
|
page = pfn_to_page(check);
|
|
/*
|
|
* 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->_count is zero at all time.
|
|
*/
|
|
if (!atomic_read(&page->_count)) {
|
|
if (PageBuddy(page))
|
|
iter += (1 << page_order(page)) - 1;
|
|
continue;
|
|
}
|
|
|
|
if (!PageLRU(page))
|
|
found++;
|
|
/*
|
|
* If there are RECLAIMABLE pages, we need to check it.
|
|
* But now, memory offline itself doesn't call shrink_slab()
|
|
* and it still to be fixed.
|
|
*/
|
|
/*
|
|
* If the page is not RAM, page_count()should be 0.
|
|
* we don't need more check. This is an _used_ not-movable page.
|
|
*
|
|
* The problematic thing here is PG_reserved pages. PG_reserved
|
|
* is set to both of a memory hole page and a _used_ kernel
|
|
* page at boot.
|
|
*/
|
|
if (found > count)
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool is_pageblock_removable_nolock(struct page *page)
|
|
{
|
|
struct zone *zone;
|
|
unsigned long pfn;
|
|
|
|
/*
|
|
* We have to be careful here because we are iterating over memory
|
|
* sections which are not zone aware so we might end up outside of
|
|
* the zone but still within the section.
|
|
* We have to take care about the node as well. If the node is offline
|
|
* its NODE_DATA will be NULL - see page_zone.
|
|
*/
|
|
if (!node_online(page_to_nid(page)))
|
|
return false;
|
|
|
|
zone = page_zone(page);
|
|
pfn = page_to_pfn(page);
|
|
if (zone->zone_start_pfn > pfn ||
|
|
zone->zone_start_pfn + zone->spanned_pages <= pfn)
|
|
return false;
|
|
|
|
return !has_unmovable_pages(zone, page, 0);
|
|
}
|
|
|
|
#ifdef CONFIG_CMA
|
|
|
|
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));
|
|
}
|
|
|
|
static struct page *
|
|
__alloc_contig_migrate_alloc(struct page *page, unsigned long private,
|
|
int **resultp)
|
|
{
|
|
gfp_t gfp_mask = GFP_USER | __GFP_MOVABLE;
|
|
|
|
if (PageHighMem(page))
|
|
gfp_mask |= __GFP_HIGHMEM;
|
|
|
|
return alloc_page(gfp_mask);
|
|
}
|
|
|
|
/* [start, end) must belong to a single zone. */
|
|
static int __alloc_contig_migrate_range(unsigned long start, unsigned long end)
|
|
{
|
|
/* This function is based on compact_zone() from compaction.c. */
|
|
|
|
unsigned long pfn = start;
|
|
unsigned int tries = 0;
|
|
int ret = 0;
|
|
|
|
struct compact_control cc = {
|
|
.nr_migratepages = 0,
|
|
.order = -1,
|
|
.zone = page_zone(pfn_to_page(start)),
|
|
.sync = true,
|
|
};
|
|
INIT_LIST_HEAD(&cc.migratepages);
|
|
|
|
migrate_prep_local();
|
|
|
|
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.zone, &cc,
|
|
pfn, end);
|
|
if (!pfn) {
|
|
ret = -EINTR;
|
|
break;
|
|
}
|
|
tries = 0;
|
|
} else if (++tries == 5) {
|
|
ret = ret < 0 ? ret : -EBUSY;
|
|
break;
|
|
}
|
|
|
|
ret = migrate_pages(&cc.migratepages,
|
|
__alloc_contig_migrate_alloc,
|
|
0, false, MIGRATE_SYNC);
|
|
}
|
|
|
|
putback_lru_pages(&cc.migratepages);
|
|
return ret > 0 ? 0 : ret;
|
|
}
|
|
|
|
/*
|
|
* Update zone's cma pages counter used for watermark level calculation.
|
|
*/
|
|
static inline void __update_cma_watermarks(struct zone *zone, int count)
|
|
{
|
|
unsigned long flags;
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
zone->min_cma_pages += count;
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
setup_per_zone_wmarks();
|
|
}
|
|
|
|
/*
|
|
* Trigger memory pressure bump to reclaim some pages in order to be able to
|
|
* allocate 'count' pages in single page units. Does similar work as
|
|
*__alloc_pages_slowpath() function.
|
|
*/
|
|
static int __reclaim_pages(struct zone *zone, gfp_t gfp_mask, int count)
|
|
{
|
|
enum zone_type high_zoneidx = gfp_zone(gfp_mask);
|
|
struct zonelist *zonelist = node_zonelist(0, gfp_mask);
|
|
int did_some_progress = 0;
|
|
int order = 1;
|
|
|
|
/*
|
|
* Increase level of watermarks to force kswapd do his job
|
|
* to stabilise at new watermark level.
|
|
*/
|
|
__update_cma_watermarks(zone, count);
|
|
|
|
/* Obey watermarks as if the page was being allocated */
|
|
while (!zone_watermark_ok(zone, 0, low_wmark_pages(zone), 0, 0)) {
|
|
wake_all_kswapd(order, zonelist, high_zoneidx, zone_idx(zone));
|
|
|
|
did_some_progress = __perform_reclaim(gfp_mask, order, zonelist,
|
|
NULL);
|
|
if (!did_some_progress) {
|
|
/* Exhausted what can be done so it's blamo time */
|
|
out_of_memory(zonelist, gfp_mask, order, NULL, false);
|
|
}
|
|
}
|
|
|
|
/* Restore original watermark levels. */
|
|
__update_cma_watermarks(zone, -count);
|
|
|
|
return count;
|
|
}
|
|
|
|
/**
|
|
* 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.
|
|
*
|
|
* The PFN range does not have to be pageblock or MAX_ORDER_NR_PAGES
|
|
* aligned, however it's the caller's responsibility to guarantee that
|
|
* we are the only thread that changes migrate type of pageblocks the
|
|
* pages fall in.
|
|
*
|
|
* The PFN range must belong to a single zone.
|
|
*
|
|
* Returns 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)
|
|
{
|
|
struct zone *zone = page_zone(pfn_to_page(start));
|
|
unsigned long outer_start, outer_end;
|
|
int ret = 0, order;
|
|
|
|
/*
|
|
* 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);
|
|
if (ret)
|
|
goto done;
|
|
|
|
ret = __alloc_contig_migrate_range(start, end);
|
|
if (ret)
|
|
goto done;
|
|
|
|
/*
|
|
* 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();
|
|
drain_all_pages();
|
|
|
|
order = 0;
|
|
outer_start = start;
|
|
while (!PageBuddy(pfn_to_page(outer_start))) {
|
|
if (++order >= MAX_ORDER) {
|
|
ret = -EBUSY;
|
|
goto done;
|
|
}
|
|
outer_start &= ~0UL << order;
|
|
}
|
|
|
|
/* Make sure the range is really isolated. */
|
|
if (test_pages_isolated(outer_start, end)) {
|
|
pr_warn("alloc_contig_range test_pages_isolated(%lx, %lx) failed\n",
|
|
outer_start, end);
|
|
ret = -EBUSY;
|
|
goto done;
|
|
}
|
|
|
|
/*
|
|
* Reclaim enough pages to make sure that contiguous allocation
|
|
* will not starve the system.
|
|
*/
|
|
__reclaim_pages(zone, GFP_HIGHUSER_MOVABLE, end-start);
|
|
|
|
/* Grab isolated pages from freelists. */
|
|
outer_end = isolate_freepages_range(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;
|
|
}
|
|
|
|
void free_contig_range(unsigned long pfn, unsigned nr_pages)
|
|
{
|
|
for (; nr_pages--; ++pfn)
|
|
__free_page(pfn_to_page(pfn));
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
static int __meminit __zone_pcp_update(void *data)
|
|
{
|
|
struct zone *zone = data;
|
|
int cpu;
|
|
unsigned long batch = zone_batchsize(zone), flags;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct per_cpu_pageset *pset;
|
|
struct per_cpu_pages *pcp;
|
|
|
|
pset = per_cpu_ptr(zone->pageset, cpu);
|
|
pcp = &pset->pcp;
|
|
|
|
local_irq_save(flags);
|
|
if (pcp->count > 0)
|
|
free_pcppages_bulk(zone, pcp->count, pcp);
|
|
setup_pageset(pset, batch);
|
|
local_irq_restore(flags);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void __meminit zone_pcp_update(struct zone *zone)
|
|
{
|
|
stop_machine(__zone_pcp_update, zone, NULL);
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_MEMORY_HOTREMOVE
|
|
void zone_pcp_reset(struct zone *zone)
|
|
{
|
|
unsigned long flags;
|
|
|
|
/* avoid races with drain_pages() */
|
|
local_irq_save(flags);
|
|
if (zone->pageset != &boot_pageset) {
|
|
free_percpu(zone->pageset);
|
|
zone->pageset = &boot_pageset;
|
|
}
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
/*
|
|
* All pages in the range must be isolated before calling this.
|
|
*/
|
|
void
|
|
__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
|
|
{
|
|
struct page *page;
|
|
struct zone *zone;
|
|
int order, i;
|
|
unsigned long pfn;
|
|
unsigned long flags;
|
|
/* find the first valid pfn */
|
|
for (pfn = start_pfn; pfn < end_pfn; pfn++)
|
|
if (pfn_valid(pfn))
|
|
break;
|
|
if (pfn == end_pfn)
|
|
return;
|
|
zone = page_zone(pfn_to_page(pfn));
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
pfn = start_pfn;
|
|
while (pfn < end_pfn) {
|
|
if (!pfn_valid(pfn)) {
|
|
pfn++;
|
|
continue;
|
|
}
|
|
page = pfn_to_page(pfn);
|
|
BUG_ON(page_count(page));
|
|
BUG_ON(!PageBuddy(page));
|
|
order = page_order(page);
|
|
#ifdef CONFIG_DEBUG_VM
|
|
printk(KERN_INFO "remove from free list %lx %d %lx\n",
|
|
pfn, 1 << order, end_pfn);
|
|
#endif
|
|
list_del(&page->lru);
|
|
rmv_page_order(page);
|
|
zone->free_area[order].nr_free--;
|
|
__mod_zone_page_state(zone, NR_FREE_PAGES,
|
|
- (1UL << order));
|
|
for (i = 0; i < (1 << order); i++)
|
|
SetPageReserved((page+i));
|
|
pfn += (1 << order);
|
|
}
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_MEMORY_FAILURE
|
|
bool is_free_buddy_page(struct page *page)
|
|
{
|
|
struct zone *zone = page_zone(page);
|
|
unsigned long pfn = page_to_pfn(page);
|
|
unsigned long flags;
|
|
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) && page_order(page_head) >= order)
|
|
break;
|
|
}
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
|
|
return order < MAX_ORDER;
|
|
}
|
|
#endif
|
|
|
|
static const struct trace_print_flags pageflag_names[] = {
|
|
{1UL << PG_locked, "locked" },
|
|
{1UL << PG_error, "error" },
|
|
{1UL << PG_referenced, "referenced" },
|
|
{1UL << PG_uptodate, "uptodate" },
|
|
{1UL << PG_dirty, "dirty" },
|
|
{1UL << PG_lru, "lru" },
|
|
{1UL << PG_active, "active" },
|
|
{1UL << PG_slab, "slab" },
|
|
{1UL << PG_owner_priv_1, "owner_priv_1" },
|
|
{1UL << PG_arch_1, "arch_1" },
|
|
{1UL << PG_reserved, "reserved" },
|
|
{1UL << PG_private, "private" },
|
|
{1UL << PG_private_2, "private_2" },
|
|
{1UL << PG_writeback, "writeback" },
|
|
#ifdef CONFIG_PAGEFLAGS_EXTENDED
|
|
{1UL << PG_head, "head" },
|
|
{1UL << PG_tail, "tail" },
|
|
#else
|
|
{1UL << PG_compound, "compound" },
|
|
#endif
|
|
{1UL << PG_swapcache, "swapcache" },
|
|
{1UL << PG_mappedtodisk, "mappedtodisk" },
|
|
{1UL << PG_reclaim, "reclaim" },
|
|
{1UL << PG_swapbacked, "swapbacked" },
|
|
{1UL << PG_unevictable, "unevictable" },
|
|
#ifdef CONFIG_MMU
|
|
{1UL << PG_mlocked, "mlocked" },
|
|
#endif
|
|
#ifdef CONFIG_ARCH_USES_PG_UNCACHED
|
|
{1UL << PG_uncached, "uncached" },
|
|
#endif
|
|
#ifdef CONFIG_MEMORY_FAILURE
|
|
{1UL << PG_hwpoison, "hwpoison" },
|
|
#endif
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
{1UL << PG_compound_lock, "compound_lock" },
|
|
#endif
|
|
};
|
|
|
|
static void dump_page_flags(unsigned long flags)
|
|
{
|
|
const char *delim = "";
|
|
unsigned long mask;
|
|
int i;
|
|
|
|
BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS);
|
|
|
|
printk(KERN_ALERT "page flags: %#lx(", flags);
|
|
|
|
/* remove zone id */
|
|
flags &= (1UL << NR_PAGEFLAGS) - 1;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(pageflag_names) && flags; i++) {
|
|
|
|
mask = pageflag_names[i].mask;
|
|
if ((flags & mask) != mask)
|
|
continue;
|
|
|
|
flags &= ~mask;
|
|
printk("%s%s", delim, pageflag_names[i].name);
|
|
delim = "|";
|
|
}
|
|
|
|
/* check for left over flags */
|
|
if (flags)
|
|
printk("%s%#lx", delim, flags);
|
|
|
|
printk(")\n");
|
|
}
|
|
|
|
void dump_page(struct page *page)
|
|
{
|
|
printk(KERN_ALERT
|
|
"page:%p count:%d mapcount:%d mapping:%p index:%#lx\n",
|
|
page, atomic_read(&page->_count), page_mapcount(page),
|
|
page->mapping, page->index);
|
|
dump_page_flags(page->flags);
|
|
mem_cgroup_print_bad_page(page);
|
|
}
|