WSL2-Linux-Kernel/include/linux/mm_inline.h

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 17:07:57 +03:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef LINUX_MM_INLINE_H
#define LINUX_MM_INLINE_H
#include <linux/atomic.h>
#include <linux/huge_mm.h>
mm: vmscan: fix do_try_to_free_pages() livelock This patch is based on KOSAKI's work and I add a little more description, please refer https://lkml.org/lkml/2012/6/14/74. Currently, I found system can enter a state that there are lots of free pages in a zone but only order-0 and order-1 pages which means the zone is heavily fragmented, then high order allocation could make direct reclaim path's long stall(ex, 60 seconds) especially in no swap and no compaciton enviroment. This problem happened on v3.4, but it seems issue still lives in current tree, the reason is do_try_to_free_pages enter live lock: kswapd will go to sleep if the zones have been fully scanned and are still not balanced. As kswapd thinks there's little point trying all over again to avoid infinite loop. Instead it changes order from high-order to 0-order because kswapd think order-0 is the most important. Look at 73ce02e9 in detail. If watermarks are ok, kswapd will go back to sleep and may leave zone->all_unreclaimable =3D 0. It assume high-order users can still perform direct reclaim if they wish. Direct reclaim continue to reclaim for a high order which is not a COSTLY_ORDER without oom-killer until kswapd turn on zone->all_unreclaimble= . This is because to avoid too early oom-kill. So it means direct_reclaim depends on kswapd to break this loop. In worst case, direct-reclaim may continue to page reclaim forever when kswapd sleeps forever until someone like watchdog detect and finally kill the process. As described in: http://thread.gmane.org/gmane.linux.kernel.mm/103737 We can't turn on zone->all_unreclaimable from direct reclaim path because direct reclaim path don't take any lock and this way is racy. Thus this patch removes zone->all_unreclaimable field completely and recalculates zone reclaimable state every time. Note: we can't take the idea that direct-reclaim see zone->pages_scanned directly and kswapd continue to use zone->all_unreclaimable. Because, it is racy. commit 929bea7c71 (vmscan: all_unreclaimable() use zone->all_unreclaimable as a name) describes the detail. [akpm@linux-foundation.org: uninline zone_reclaimable_pages() and zone_reclaimable()] Cc: Aaditya Kumar <aaditya.kumar.30@gmail.com> Cc: Ying Han <yinghan@google.com> Cc: Nick Piggin <npiggin@gmail.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Christoph Lameter <cl@linux.com> Cc: Bob Liu <lliubbo@gmail.com> Cc: Neil Zhang <zhangwm@marvell.com> Cc: Russell King - ARM Linux <linux@arm.linux.org.uk> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Lisa Du <cldu@marvell.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12 01:22:36 +04:00
#include <linux/swap.h>
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
#include <linux/string.h>
#include <linux/userfaultfd_k.h>
#include <linux/swapops.h>
/**
* folio_is_file_lru - Should the folio be on a file LRU or anon LRU?
* @folio: The folio to test.
*
* We would like to get this info without a page flag, but the state
* needs to survive until the folio is last deleted from the LRU, which
* could be as far down as __page_cache_release.
*
* Return: An integer (not a boolean!) used to sort a folio onto the
* right LRU list and to account folios correctly.
* 1 if @folio is a regular filesystem backed page cache folio
* or a lazily freed anonymous folio (e.g. via MADV_FREE).
* 0 if @folio is a normal anonymous folio, a tmpfs folio or otherwise
* ram or swap backed folio.
*/
static inline int folio_is_file_lru(struct folio *folio)
{
return !folio_test_swapbacked(folio);
}
static inline int page_is_file_lru(struct page *page)
{
return folio_is_file_lru(page_folio(page));
}
static __always_inline void update_lru_size(struct lruvec *lruvec,
mm, vmscan: move LRU lists to node This moves the LRU lists from the zone to the node and related data such as counters, tracing, congestion tracking and writeback tracking. Unfortunately, due to reclaim and compaction retry logic, it is necessary to account for the number of LRU pages on both zone and node logic. Most reclaim logic is based on the node counters but the retry logic uses the zone counters which do not distinguish inactive and active sizes. It would be possible to leave the LRU counters on a per-zone basis but it's a heavier calculation across multiple cache lines that is much more frequent than the retry checks. Other than the LRU counters, this is mostly a mechanical patch but note that it introduces a number of anomalies. For example, the scans are per-zone but using per-node counters. We also mark a node as congested when a zone is congested. This causes weird problems that are fixed later but is easier to review. In the event that there is excessive overhead on 32-bit systems due to the nodes being on LRU then there are two potential solutions 1. Long-term isolation of highmem pages when reclaim is lowmem When pages are skipped, they are immediately added back onto the LRU list. If lowmem reclaim persisted for long periods of time, the same highmem pages get continually scanned. The idea would be that lowmem keeps those pages on a separate list until a reclaim for highmem pages arrives that splices the highmem pages back onto the LRU. It potentially could be implemented similar to the UNEVICTABLE list. That would reduce the skip rate with the potential corner case is that highmem pages have to be scanned and reclaimed to free lowmem slab pages. 2. Linear scan lowmem pages if the initial LRU shrink fails This will break LRU ordering but may be preferable and faster during memory pressure than skipping LRU pages. Link: http://lkml.kernel.org/r/1467970510-21195-4-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-29 01:45:31 +03:00
enum lru_list lru, enum zone_type zid,
long nr_pages)
mm: update_lru_size do the __mod_zone_page_state Konstantin Khlebnikov pointed out (nearly four years ago, when lumpy reclaim was removed) that lru_size can be updated by -nr_taken once per call to isolate_lru_pages(), instead of page by page. Update it inside isolate_lru_pages(), or at its two callsites? I chose to update it at the callsites, rearranging and grouping the updates by nr_taken and nr_scanned together in both. With one exception, mem_cgroup_update_lru_size(,lru,) is then used where __mod_zone_page_state(,NR_LRU_BASE+lru,) is used; and we shall be adding some more calls in a future commit. Make the code a little smaller and simpler by incorporating stat update in lru_size update. The exception was move_active_pages_to_lru(), which aggregated the pgmoved stat update separately from the individual lru_size updates; but I still think this a simplification worth making. However, the __mod_zone_page_state is not peculiar to mem_cgroups: so better use the name update_lru_size, calls mem_cgroup_update_lru_size when CONFIG_MEMCG. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andres Lagar-Cavilla <andreslc@google.com> Cc: Yang Shi <yang.shi@linaro.org> Cc: Ning Qu <quning@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20 03:12:38 +03:00
{
mm, vmscan: move LRU lists to node This moves the LRU lists from the zone to the node and related data such as counters, tracing, congestion tracking and writeback tracking. Unfortunately, due to reclaim and compaction retry logic, it is necessary to account for the number of LRU pages on both zone and node logic. Most reclaim logic is based on the node counters but the retry logic uses the zone counters which do not distinguish inactive and active sizes. It would be possible to leave the LRU counters on a per-zone basis but it's a heavier calculation across multiple cache lines that is much more frequent than the retry checks. Other than the LRU counters, this is mostly a mechanical patch but note that it introduces a number of anomalies. For example, the scans are per-zone but using per-node counters. We also mark a node as congested when a zone is congested. This causes weird problems that are fixed later but is easier to review. In the event that there is excessive overhead on 32-bit systems due to the nodes being on LRU then there are two potential solutions 1. Long-term isolation of highmem pages when reclaim is lowmem When pages are skipped, they are immediately added back onto the LRU list. If lowmem reclaim persisted for long periods of time, the same highmem pages get continually scanned. The idea would be that lowmem keeps those pages on a separate list until a reclaim for highmem pages arrives that splices the highmem pages back onto the LRU. It potentially could be implemented similar to the UNEVICTABLE list. That would reduce the skip rate with the potential corner case is that highmem pages have to be scanned and reclaimed to free lowmem slab pages. 2. Linear scan lowmem pages if the initial LRU shrink fails This will break LRU ordering but may be preferable and faster during memory pressure than skipping LRU pages. Link: http://lkml.kernel.org/r/1467970510-21195-4-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-29 01:45:31 +03:00
struct pglist_data *pgdat = lruvec_pgdat(lruvec);
mm: memcontrol: track LRU counts in the vmstats array Patch series "mm: memcontrol: clean up the LRU counts tracking". The memcg LRU stats usage is currently a bit messy. Memcg has private per-zone counters because reclaim needs zone granularity sometimes, but we also have plenty of users that need to awkwardly sum them up to node or memcg granularity. Meanwhile the canonical per-memcg vmstats do not track the LRU counts (NR_INACTIVE_ANON etc.) as you'd expect. This series enables LRU count tracking in the per-memcg vmstats array such that lruvec_page_state() and memcg_page_state() work on the enum node_stat_item items for the LRU counters. Then it converts all the callers that don't specifically need per-zone numbers over to that. This patch (of 6): The memcg code currently maintains private per-zone breakdowns of the LRU counters. This is necessary for reclaim decisions which are still zone-based, but there are a variety of users of these counters that only want the aggregate per-lruvec or per-memcg LRU counts, and they need to painfully sum up the zone counters on each request for that. These would be better served using the memcg vmstats arrays, which track VM statistics at the desired scope already. They just don't have the LRU counts right now. So to kick off the conversion, begin tracking LRU counts in those. Link: http://lkml.kernel.org/r/20190228163020.24100-2-hannes@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Roman Gushchin <guro@fb.com> Cc: Tejun Heo <tj@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 03:17:57 +03:00
__mod_lruvec_state(lruvec, NR_LRU_BASE + lru, nr_pages);
mm: add per-zone lru list stat When I did stress test with hackbench, I got OOM message frequently which didn't ever happen in zone-lru. gfp_mask=0x26004c0(GFP_KERNEL|__GFP_REPEAT|__GFP_NOTRACK), order=0 .. .. __alloc_pages_nodemask+0xe52/0xe60 ? new_slab+0x39c/0x3b0 new_slab+0x39c/0x3b0 ___slab_alloc.constprop.87+0x6da/0x840 ? __alloc_skb+0x3c/0x260 ? _raw_spin_unlock_irq+0x27/0x60 ? trace_hardirqs_on_caller+0xec/0x1b0 ? finish_task_switch+0xa6/0x220 ? poll_select_copy_remaining+0x140/0x140 __slab_alloc.isra.81.constprop.86+0x40/0x6d ? __alloc_skb+0x3c/0x260 kmem_cache_alloc+0x22c/0x260 ? __alloc_skb+0x3c/0x260 __alloc_skb+0x3c/0x260 alloc_skb_with_frags+0x4e/0x1a0 sock_alloc_send_pskb+0x16a/0x1b0 ? wait_for_unix_gc+0x31/0x90 ? alloc_set_pte+0x2ad/0x310 unix_stream_sendmsg+0x28d/0x340 sock_sendmsg+0x2d/0x40 sock_write_iter+0x6c/0xc0 __vfs_write+0xc0/0x120 vfs_write+0x9b/0x1a0 ? __might_fault+0x49/0xa0 SyS_write+0x44/0x90 do_fast_syscall_32+0xa6/0x1e0 sysenter_past_esp+0x45/0x74 Mem-Info: active_anon:104698 inactive_anon:105791 isolated_anon:192 active_file:433 inactive_file:283 isolated_file:22 unevictable:0 dirty:0 writeback:296 unstable:0 slab_reclaimable:6389 slab_unreclaimable:78927 mapped:474 shmem:0 pagetables:101426 bounce:0 free:10518 free_pcp:334 free_cma:0 Node 0 active_anon:418792kB inactive_anon:423164kB active_file:1732kB inactive_file:1132kB unevictable:0kB isolated(anon):768kB isolated(file):88kB mapped:1896kB dirty:0kB writeback:1184kB shmem:0kB writeback_tmp:0kB unstable:0kB pages_scanned:1478632 all_unreclaimable? yes DMA free:3304kB min:68kB low:84kB high:100kB present:15992kB managed:15916kB mlocked:0kB slab_reclaimable:0kB slab_unreclaimable:4088kB kernel_stack:0kB pagetables:2480kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB lowmem_reserve[]: 0 809 1965 1965 Normal free:3436kB min:3604kB low:4504kB high:5404kB present:897016kB managed:858460kB mlocked:0kB slab_reclaimable:25556kB slab_unreclaimable:311712kB kernel_stack:164608kB pagetables:30844kB bounce:0kB free_pcp:620kB local_pcp:104kB free_cma:0kB lowmem_reserve[]: 0 0 9247 9247 HighMem free:33808kB min:512kB low:1796kB high:3080kB present:1183736kB managed:1183736kB mlocked:0kB slab_reclaimable:0kB slab_unreclaimable:0kB kernel_stack:0kB pagetables:372252kB bounce:0kB free_pcp:428kB local_pcp:72kB free_cma:0kB lowmem_reserve[]: 0 0 0 0 DMA: 2*4kB (UM) 2*8kB (UM) 0*16kB 1*32kB (U) 1*64kB (U) 2*128kB (UM) 1*256kB (U) 1*512kB (M) 0*1024kB 1*2048kB (U) 0*4096kB = 3192kB Normal: 33*4kB (MH) 79*8kB (ME) 11*16kB (M) 4*32kB (M) 2*64kB (ME) 2*128kB (EH) 7*256kB (EH) 0*512kB 0*1024kB 0*2048kB 0*4096kB = 3244kB HighMem: 2590*4kB (UM) 1568*8kB (UM) 491*16kB (UM) 60*32kB (UM) 6*64kB (M) 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 33064kB Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB 25121 total pagecache pages 24160 pages in swap cache Swap cache stats: add 86371, delete 62211, find 42865/60187 Free swap = 4015560kB Total swap = 4192252kB 524186 pages RAM 295934 pages HighMem/MovableOnly 9658 pages reserved 0 pages cma reserved The order-0 allocation for normal zone failed while there are a lot of reclaimable memory(i.e., anonymous memory with free swap). I wanted to analyze the problem but it was hard because we removed per-zone lru stat so I couldn't know how many of anonymous memory there are in normal/dma zone. When we investigate OOM problem, reclaimable memory count is crucial stat to find a problem. Without it, it's hard to parse the OOM message so I believe we should keep it. With per-zone lru stat, gfp_mask=0x26004c0(GFP_KERNEL|__GFP_REPEAT|__GFP_NOTRACK), order=0 Mem-Info: active_anon:101103 inactive_anon:102219 isolated_anon:0 active_file:503 inactive_file:544 isolated_file:0 unevictable:0 dirty:0 writeback:34 unstable:0 slab_reclaimable:6298 slab_unreclaimable:74669 mapped:863 shmem:0 pagetables:100998 bounce:0 free:23573 free_pcp:1861 free_cma:0 Node 0 active_anon:404412kB inactive_anon:409040kB active_file:2012kB inactive_file:2176kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:3452kB dirty:0kB writeback:136kB shmem:0kB writeback_tmp:0kB unstable:0kB pages_scanned:1320845 all_unreclaimable? yes DMA free:3296kB min:68kB low:84kB high:100kB active_anon:5540kB inactive_anon:0kB active_file:0kB inactive_file:0kB present:15992kB managed:15916kB mlocked:0kB slab_reclaimable:248kB slab_unreclaimable:2628kB kernel_stack:792kB pagetables:2316kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB lowmem_reserve[]: 0 809 1965 1965 Normal free:3600kB min:3604kB low:4504kB high:5404kB active_anon:86304kB inactive_anon:0kB active_file:160kB inactive_file:376kB present:897016kB managed:858524kB mlocked:0kB slab_reclaimable:24944kB slab_unreclaimable:296048kB kernel_stack:163832kB pagetables:35892kB bounce:0kB free_pcp:3076kB local_pcp:656kB free_cma:0kB lowmem_reserve[]: 0 0 9247 9247 HighMem free:86156kB min:512kB low:1796kB high:3080kB active_anon:312852kB inactive_anon:410024kB active_file:1924kB inactive_file:2012kB present:1183736kB managed:1183736kB mlocked:0kB slab_reclaimable:0kB slab_unreclaimable:0kB kernel_stack:0kB pagetables:365784kB bounce:0kB free_pcp:3868kB local_pcp:720kB free_cma:0kB lowmem_reserve[]: 0 0 0 0 DMA: 8*4kB (UM) 8*8kB (UM) 4*16kB (M) 2*32kB (UM) 2*64kB (UM) 1*128kB (M) 3*256kB (UME) 2*512kB (UE) 1*1024kB (E) 0*2048kB 0*4096kB = 3296kB Normal: 240*4kB (UME) 160*8kB (UME) 23*16kB (ME) 3*32kB (UE) 3*64kB (UME) 2*128kB (ME) 1*256kB (U) 0*512kB 0*1024kB 0*2048kB 0*4096kB = 3408kB HighMem: 10942*4kB (UM) 3102*8kB (UM) 866*16kB (UM) 76*32kB (UM) 11*64kB (UM) 4*128kB (UM) 1*256kB (M) 0*512kB 0*1024kB 0*2048kB 0*4096kB = 86344kB Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB 54409 total pagecache pages 53215 pages in swap cache Swap cache stats: add 300982, delete 247765, find 157978/226539 Free swap = 3803244kB Total swap = 4192252kB 524186 pages RAM 295934 pages HighMem/MovableOnly 9642 pages reserved 0 pages cma reserved With that, we can see normal zone has a 86M reclaimable memory so we can know something goes wrong(I will fix the problem in next patch) in reclaim. [mgorman@techsingularity.net: rename zone LRU stats in /proc/vmstat] Link: http://lkml.kernel.org/r/20160725072300.GK10438@techsingularity.net Link: http://lkml.kernel.org/r/1469110261-7365-2-git-send-email-mgorman@techsingularity.net Signed-off-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-29 01:47:26 +03:00
__mod_zone_page_state(&pgdat->node_zones[zid],
NR_ZONE_LRU_BASE + lru, nr_pages);
mm, vmscan: Update all zone LRU sizes before updating memcg Minchan Kim reported setting the following warning on a 32-bit system although it can affect 64-bit systems. WARNING: CPU: 4 PID: 1322 at mm/memcontrol.c:998 mem_cgroup_update_lru_size+0x103/0x110 mem_cgroup_update_lru_size(f44b4000, 1, -7): zid 1 lru_size 1 but empty Modules linked in: CPU: 4 PID: 1322 Comm: cp Not tainted 4.7.0-rc4-mm1+ #143 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: dump_stack+0x76/0xaf __warn+0xea/0x110 ? mem_cgroup_update_lru_size+0x103/0x110 warn_slowpath_fmt+0x3b/0x40 mem_cgroup_update_lru_size+0x103/0x110 isolate_lru_pages.isra.61+0x2e2/0x360 shrink_active_list+0xac/0x2a0 ? __delay+0xe/0x10 shrink_node_memcg+0x53c/0x7a0 shrink_node+0xab/0x2a0 do_try_to_free_pages+0xc6/0x390 try_to_free_pages+0x245/0x590 LRU list contents and counts are updated separately. Counts are updated before pages are added to the LRU and updated after pages are removed. The warning above is from a check in mem_cgroup_update_lru_size that ensures that list sizes of zero are empty. The problem is that node-lru needs to account for highmem pages if CONFIG_HIGHMEM is set. One impact of the implementation is that the sizes are updated in multiple passes when pages from multiple zones were isolated. This happens whether HIGHMEM is set or not. When multiple zones are isolated, it's possible for a debugging check in memcg to be tripped. This patch forces all the zone counts to be updated before the memcg function is called. Link: http://lkml.kernel.org/r/1468588165-12461-6-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Tested-by: Minchan Kim <minchan@kernel.org> Reported-by: Minchan Kim <minchan@kernel.org> Acked-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-29 01:47:17 +03:00
#ifdef CONFIG_MEMCG
mm, memcg: fix the active list aging for lowmem requests when memcg is enabled Nils Holland and Klaus Ethgen have reported unexpected OOM killer invocations with 32b kernel starting with 4.8 kernels kworker/u4:5 invoked oom-killer: gfp_mask=0x2400840(GFP_NOFS|__GFP_NOFAIL), nodemask=0, order=0, oom_score_adj=0 kworker/u4:5 cpuset=/ mems_allowed=0 CPU: 1 PID: 2603 Comm: kworker/u4:5 Not tainted 4.9.0-gentoo #2 [...] Mem-Info: active_anon:58685 inactive_anon:90 isolated_anon:0 active_file:274324 inactive_file:281962 isolated_file:0 unevictable:0 dirty:649 writeback:0 unstable:0 slab_reclaimable:40662 slab_unreclaimable:17754 mapped:7382 shmem:202 pagetables:351 bounce:0 free:206736 free_pcp:332 free_cma:0 Node 0 active_anon:234740kB inactive_anon:360kB active_file:1097296kB inactive_file:1127848kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:29528kB dirty:2596kB writeback:0kB shmem:0kB shmem_thp: 0kB shmem_pmdmapped: 184320kB anon_thp: 808kB writeback_tmp:0kB unstable:0kB pages_scanned:0 all_unreclaimable? no DMA free:3952kB min:788kB low:984kB high:1180kB active_anon:0kB inactive_anon:0kB active_file:7316kB inactive_file:0kB unevictable:0kB writepending:96kB present:15992kB managed:15916kB mlocked:0kB slab_reclaimable:3200kB slab_unreclaimable:1408kB kernel_stack:0kB pagetables:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB lowmem_reserve[]: 0 813 3474 3474 Normal free:41332kB min:41368kB low:51708kB high:62048kB active_anon:0kB inactive_anon:0kB active_file:532748kB inactive_file:44kB unevictable:0kB writepending:24kB present:897016kB managed:836248kB mlocked:0kB slab_reclaimable:159448kB slab_unreclaimable:69608kB kernel_stack:1112kB pagetables:1404kB bounce:0kB free_pcp:528kB local_pcp:340kB free_cma:0kB lowmem_reserve[]: 0 0 21292 21292 HighMem free:781660kB min:512kB low:34356kB high:68200kB active_anon:234740kB inactive_anon:360kB active_file:557232kB inactive_file:1127804kB unevictable:0kB writepending:2592kB present:2725384kB managed:2725384kB mlocked:0kB slab_reclaimable:0kB slab_unreclaimable:0kB kernel_stack:0kB pagetables:0kB bounce:0kB free_pcp:800kB local_pcp:608kB free_cma:0kB the oom killer is clearly pre-mature because there there is still a lot of page cache in the zone Normal which should satisfy this lowmem request. Further debugging has shown that the reclaim cannot make any forward progress because the page cache is hidden in the active list which doesn't get rotated because inactive_list_is_low is not memcg aware. The code simply subtracts per-zone highmem counters from the respective memcg's lru sizes which doesn't make any sense. We can simply end up always seeing the resulting active and inactive counts 0 and return false. This issue is not limited to 32b kernels but in practice the effect on systems without CONFIG_HIGHMEM would be much harder to notice because we do not invoke the OOM killer for allocations requests targeting < ZONE_NORMAL. Fix the issue by tracking per zone lru page counts in mem_cgroup_per_node and subtract per-memcg highmem counts when memcg is enabled. Introduce helper lruvec_zone_lru_size which redirects to either zone counters or mem_cgroup_get_zone_lru_size when appropriate. We are losing empty LRU but non-zero lru size detection introduced by ca707239e8a7 ("mm: update_lru_size warn and reset bad lru_size") because of the inherent zone vs. node discrepancy. Fixes: f8d1a31163fc ("mm: consider whether to decivate based on eligible zones inactive ratio") Link: http://lkml.kernel.org/r/20170104100825.3729-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Nils Holland <nholland@tisys.org> Tested-by: Nils Holland <nholland@tisys.org> Reported-by: Klaus Ethgen <Klaus@Ethgen.de> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: <stable@vger.kernel.org> [4.8+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-11 03:58:04 +03:00
mem_cgroup_update_lru_size(lruvec, lru, zid, nr_pages);
mm: update_lru_size do the __mod_zone_page_state Konstantin Khlebnikov pointed out (nearly four years ago, when lumpy reclaim was removed) that lru_size can be updated by -nr_taken once per call to isolate_lru_pages(), instead of page by page. Update it inside isolate_lru_pages(), or at its two callsites? I chose to update it at the callsites, rearranging and grouping the updates by nr_taken and nr_scanned together in both. With one exception, mem_cgroup_update_lru_size(,lru,) is then used where __mod_zone_page_state(,NR_LRU_BASE+lru,) is used; and we shall be adding some more calls in a future commit. Make the code a little smaller and simpler by incorporating stat update in lru_size update. The exception was move_active_pages_to_lru(), which aggregated the pgmoved stat update separately from the individual lru_size updates; but I still think this a simplification worth making. However, the __mod_zone_page_state is not peculiar to mem_cgroups: so better use the name update_lru_size, calls mem_cgroup_update_lru_size when CONFIG_MEMCG. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andres Lagar-Cavilla <andreslc@google.com> Cc: Yang Shi <yang.shi@linaro.org> Cc: Ning Qu <quning@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20 03:12:38 +03:00
#endif
}
/**
* __folio_clear_lru_flags - Clear page lru flags before releasing a page.
* @folio: The folio that was on lru and now has a zero reference.
*/
static __always_inline void __folio_clear_lru_flags(struct folio *folio)
{
VM_BUG_ON_FOLIO(!folio_test_lru(folio), folio);
__folio_clear_lru(folio);
/* this shouldn't happen, so leave the flags to bad_page() */
if (folio_test_active(folio) && folio_test_unevictable(folio))
return;
__folio_clear_active(folio);
__folio_clear_unevictable(folio);
}
static __always_inline void __clear_page_lru_flags(struct page *page)
{
__folio_clear_lru_flags(page_folio(page));
}
[PATCH] Swap Migration V5: LRU operations This is the start of the `swap migration' patch series. Swap migration allows the moving of the physical location of pages between nodes in a numa system while the process is running. This means that the virtual addresses that the process sees do not change. However, the system rearranges the physical location of those pages. The main intent of page migration patches here is to reduce the latency of memory access by moving pages near to the processor where the process accessing that memory is running. The patchset allows a process to manually relocate the node on which its pages are located through the MF_MOVE and MF_MOVE_ALL options while setting a new memory policy. The pages of process can also be relocated from another process using the sys_migrate_pages() function call. Requires CAP_SYS_ADMIN. The migrate_pages function call takes two sets of nodes and moves pages of a process that are located on the from nodes to the destination nodes. Manual migration is very useful if for example the scheduler has relocated a process to a processor on a distant node. A batch scheduler or an administrator can detect the situation and move the pages of the process nearer to the new processor. sys_migrate_pages() could be used on non-numa machines as well, to force all of a particualr process's pages out to swap, if someone thinks that's useful. Larger installations usually partition the system using cpusets into sections of nodes. Paul has equipped cpusets with the ability to move pages when a task is moved to another cpuset. This allows automatic control over locality of a process. If a task is moved to a new cpuset then also all its pages are moved with it so that the performance of the process does not sink dramatically (as is the case today). Swap migration works by simply evicting the page. The pages must be faulted back in. The pages are then typically reallocated by the system near the node where the process is executing. For swap migration the destination of the move is controlled by the allocation policy. Cpusets set the allocation policy before calling sys_migrate_pages() in order to move the pages as intended. No allocation policy changes are performed for sys_migrate_pages(). This means that the pages may not faulted in to the specified nodes if no allocation policy was set by other means. The pages will just end up near the node where the fault occurred. There's another patch series in the pipeline which implements "direct migration". The direct migration patchset extends the migration functionality to avoid going through swap. The destination node of the relation is controllable during the actual moving of pages. The crutch of using the allocation policy to relocate is not necessary and the pages are moved directly to the target. Its also faster since swap is not used. And sys_migrate_pages() can then move pages directly to the specified node. Implement functions to isolate pages from the LRU and put them back later. This patch: An earlier implementation was provided by Hirokazu Takahashi <taka@valinux.co.jp> and IWAMOTO Toshihiro <iwamoto@valinux.co.jp> for the memory hotplug project. From: Magnus This breaks out isolate_lru_page() and putpack_lru_page(). Needed for swap migration. Signed-off-by: Magnus Damm <magnus.damm@gmail.com> Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 12:00:45 +03:00
/**
* folio_lru_list - Which LRU list should a folio be on?
* @folio: The folio to test.
*
* Return: The LRU list a folio should be on, as an index
* into the array of LRU lists.
*/
static __always_inline enum lru_list folio_lru_list(struct folio *folio)
{
enum lru_list lru;
VM_BUG_ON_FOLIO(folio_test_active(folio) && folio_test_unevictable(folio), folio);
if (folio_test_unevictable(folio))
return LRU_UNEVICTABLE;
lru = folio_is_file_lru(folio) ? LRU_INACTIVE_FILE : LRU_INACTIVE_ANON;
if (folio_test_active(folio))
lru += LRU_ACTIVE;
return lru;
}
static __always_inline
void lruvec_add_folio(struct lruvec *lruvec, struct folio *folio)
{
enum lru_list lru = folio_lru_list(folio);
update_lru_size(lruvec, lru, folio_zonenum(folio),
folio_nr_pages(folio));
mm/munlock: maintain page->mlock_count while unevictable Previous patches have been preparatory: now implement page->mlock_count. The ordering of the "Unevictable LRU" is of no significance, and there is no point holding unevictable pages on a list: place page->mlock_count to overlay page->lru.prev (since page->lru.next is overlaid by compound_head, which needs to be even so as not to satisfy PageTail - though 2 could be added instead of 1 for each mlock, if that's ever an improvement). But it's only safe to rely on or modify page->mlock_count while lruvec lock is held and page is on unevictable "LRU" - we can save lots of edits by continuing to pretend that there's an imaginary LRU here (there is an unevictable count which still needs to be maintained, but not a list). The mlock_count technique suffers from an unreliability much like with page_mlock(): while someone else has the page off LRU, not much can be done. As before, err on the safe side (behave as if mlock_count 0), and let try_to_unlock_one() move the page to unevictable if reclaim finds out later on - a few misplaced pages don't matter, what we want to avoid is imbalancing reclaim by flooding evictable lists with unevictable pages. I am not a fan of "if (!isolate_lru_page(page)) putback_lru_page(page);": if we have taken lruvec lock to get the page off its present list, then we save everyone trouble (and however many extra atomic ops) by putting it on its destination list immediately. Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-02-15 05:29:54 +03:00
if (lru != LRU_UNEVICTABLE)
list_add(&folio->lru, &lruvec->lists[lru]);
}
static __always_inline void add_page_to_lru_list(struct page *page,
struct lruvec *lruvec)
{
lruvec_add_folio(lruvec, page_folio(page));
}
static __always_inline
void lruvec_add_folio_tail(struct lruvec *lruvec, struct folio *folio)
{
enum lru_list lru = folio_lru_list(folio);
update_lru_size(lruvec, lru, folio_zonenum(folio),
folio_nr_pages(folio));
mm/munlock: maintain page->mlock_count while unevictable Previous patches have been preparatory: now implement page->mlock_count. The ordering of the "Unevictable LRU" is of no significance, and there is no point holding unevictable pages on a list: place page->mlock_count to overlay page->lru.prev (since page->lru.next is overlaid by compound_head, which needs to be even so as not to satisfy PageTail - though 2 could be added instead of 1 for each mlock, if that's ever an improvement). But it's only safe to rely on or modify page->mlock_count while lruvec lock is held and page is on unevictable "LRU" - we can save lots of edits by continuing to pretend that there's an imaginary LRU here (there is an unevictable count which still needs to be maintained, but not a list). The mlock_count technique suffers from an unreliability much like with page_mlock(): while someone else has the page off LRU, not much can be done. As before, err on the safe side (behave as if mlock_count 0), and let try_to_unlock_one() move the page to unevictable if reclaim finds out later on - a few misplaced pages don't matter, what we want to avoid is imbalancing reclaim by flooding evictable lists with unevictable pages. I am not a fan of "if (!isolate_lru_page(page)) putback_lru_page(page);": if we have taken lruvec lock to get the page off its present list, then we save everyone trouble (and however many extra atomic ops) by putting it on its destination list immediately. Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-02-15 05:29:54 +03:00
/* This is not expected to be used on LRU_UNEVICTABLE */
list_add_tail(&folio->lru, &lruvec->lists[lru]);
}
static __always_inline void add_page_to_lru_list_tail(struct page *page,
struct lruvec *lruvec)
{
lruvec_add_folio_tail(lruvec, page_folio(page));
}
static __always_inline
void lruvec_del_folio(struct lruvec *lruvec, struct folio *folio)
{
mm/munlock: maintain page->mlock_count while unevictable Previous patches have been preparatory: now implement page->mlock_count. The ordering of the "Unevictable LRU" is of no significance, and there is no point holding unevictable pages on a list: place page->mlock_count to overlay page->lru.prev (since page->lru.next is overlaid by compound_head, which needs to be even so as not to satisfy PageTail - though 2 could be added instead of 1 for each mlock, if that's ever an improvement). But it's only safe to rely on or modify page->mlock_count while lruvec lock is held and page is on unevictable "LRU" - we can save lots of edits by continuing to pretend that there's an imaginary LRU here (there is an unevictable count which still needs to be maintained, but not a list). The mlock_count technique suffers from an unreliability much like with page_mlock(): while someone else has the page off LRU, not much can be done. As before, err on the safe side (behave as if mlock_count 0), and let try_to_unlock_one() move the page to unevictable if reclaim finds out later on - a few misplaced pages don't matter, what we want to avoid is imbalancing reclaim by flooding evictable lists with unevictable pages. I am not a fan of "if (!isolate_lru_page(page)) putback_lru_page(page);": if we have taken lruvec lock to get the page off its present list, then we save everyone trouble (and however many extra atomic ops) by putting it on its destination list immediately. Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-02-15 05:29:54 +03:00
enum lru_list lru = folio_lru_list(folio);
if (lru != LRU_UNEVICTABLE)
list_del(&folio->lru);
update_lru_size(lruvec, lru, folio_zonenum(folio),
-folio_nr_pages(folio));
}
static __always_inline void del_page_from_lru_list(struct page *page,
struct lruvec *lruvec)
{
lruvec_del_folio(lruvec, page_folio(page));
}
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
#ifdef CONFIG_ANON_VMA_NAME
/*
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* mmap_lock should be read-locked when calling anon_vma_name(). Caller should
* either keep holding the lock while using the returned pointer or it should
* raise anon_vma_name refcount before releasing the lock.
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
*/
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extern struct anon_vma_name *anon_vma_name(struct vm_area_struct *vma);
extern struct anon_vma_name *anon_vma_name_alloc(const char *name);
extern void anon_vma_name_free(struct kref *kref);
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
2022-03-05 07:28:51 +03:00
/* mmap_lock should be read-locked */
static inline void anon_vma_name_get(struct anon_vma_name *anon_name)
{
if (anon_name)
kref_get(&anon_name->kref);
}
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
2022-03-05 07:28:51 +03:00
static inline void anon_vma_name_put(struct anon_vma_name *anon_name)
{
if (anon_name)
kref_put(&anon_name->kref, anon_vma_name_free);
}
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
mm: prevent vm_area_struct::anon_name refcount saturation A deep process chain with many vmas could grow really high. With default sysctl_max_map_count (64k) and default pid_max (32k) the max number of vmas in the system is 2147450880 and the refcounter has headroom of 1073774592 before it reaches REFCOUNT_SATURATED (3221225472). Therefore it's unlikely that an anonymous name refcounter will overflow with these defaults. Currently the max for pid_max is PID_MAX_LIMIT (4194304) and for sysctl_max_map_count it's INT_MAX (2147483647). In this configuration anon_vma_name refcount overflow becomes theoretically possible (that still require heavy sharing of that anon_vma_name between processes). kref refcounting interface used in anon_vma_name structure will detect a counter overflow when it reaches REFCOUNT_SATURATED value but will only generate a warning and freeze the ref counter. This would lead to the refcounted object never being freed. A determined attacker could leak memory like that but it would be rather expensive and inefficient way to do so. To ensure anon_vma_name refcount does not overflow, stop anon_vma_name sharing when the refcount reaches REFCOUNT_MAX (2147483647), which still leaves INT_MAX/2 (1073741823) values before the counter reaches REFCOUNT_SATURATED. This should provide enough headroom for raising the refcounts temporarily. Link: https://lkml.kernel.org/r/20220223153613.835563-2-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Suggested-by: Michal Hocko <mhocko@suse.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Alexey Gladkov <legion@kernel.org> Cc: Chris Hyser <chris.hyser@oracle.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Colin Cross <ccross@google.com> Cc: Cyrill Gorcunov <gorcunov@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kees Cook <keescook@chromium.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Collingbourne <pcc@google.com> Cc: Sasha Levin <sashal@kernel.org> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xiaofeng Cao <caoxiaofeng@yulong.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-05 07:28:55 +03:00
static inline
struct anon_vma_name *anon_vma_name_reuse(struct anon_vma_name *anon_name)
{
/* Prevent anon_name refcount saturation early on */
if (kref_read(&anon_name->kref) < REFCOUNT_MAX) {
anon_vma_name_get(anon_name);
return anon_name;
}
return anon_vma_name_alloc(anon_name->name);
}
2022-03-05 07:28:51 +03:00
static inline void dup_anon_vma_name(struct vm_area_struct *orig_vma,
struct vm_area_struct *new_vma)
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
{
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struct anon_vma_name *anon_name = anon_vma_name(orig_vma);
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
mm: prevent vm_area_struct::anon_name refcount saturation A deep process chain with many vmas could grow really high. With default sysctl_max_map_count (64k) and default pid_max (32k) the max number of vmas in the system is 2147450880 and the refcounter has headroom of 1073774592 before it reaches REFCOUNT_SATURATED (3221225472). Therefore it's unlikely that an anonymous name refcounter will overflow with these defaults. Currently the max for pid_max is PID_MAX_LIMIT (4194304) and for sysctl_max_map_count it's INT_MAX (2147483647). In this configuration anon_vma_name refcount overflow becomes theoretically possible (that still require heavy sharing of that anon_vma_name between processes). kref refcounting interface used in anon_vma_name structure will detect a counter overflow when it reaches REFCOUNT_SATURATED value but will only generate a warning and freeze the ref counter. This would lead to the refcounted object never being freed. A determined attacker could leak memory like that but it would be rather expensive and inefficient way to do so. To ensure anon_vma_name refcount does not overflow, stop anon_vma_name sharing when the refcount reaches REFCOUNT_MAX (2147483647), which still leaves INT_MAX/2 (1073741823) values before the counter reaches REFCOUNT_SATURATED. This should provide enough headroom for raising the refcounts temporarily. Link: https://lkml.kernel.org/r/20220223153613.835563-2-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Suggested-by: Michal Hocko <mhocko@suse.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Alexey Gladkov <legion@kernel.org> Cc: Chris Hyser <chris.hyser@oracle.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Colin Cross <ccross@google.com> Cc: Cyrill Gorcunov <gorcunov@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kees Cook <keescook@chromium.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Collingbourne <pcc@google.com> Cc: Sasha Levin <sashal@kernel.org> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xiaofeng Cao <caoxiaofeng@yulong.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-05 07:28:55 +03:00
if (anon_name)
new_vma->anon_name = anon_vma_name_reuse(anon_name);
2022-03-05 07:28:51 +03:00
}
static inline void free_anon_vma_name(struct vm_area_struct *vma)
{
/*
* Not using anon_vma_name because it generates a warning if mmap_lock
* is not held, which might be the case here.
*/
if (!vma->vm_file)
anon_vma_name_put(vma->anon_name);
}
static inline bool anon_vma_name_eq(struct anon_vma_name *anon_name1,
struct anon_vma_name *anon_name2)
{
if (anon_name1 == anon_name2)
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
return true;
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return anon_name1 && anon_name2 &&
!strcmp(anon_name1->name, anon_name2->name);
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
}
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mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
#else /* CONFIG_ANON_VMA_NAME */
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static inline struct anon_vma_name *anon_vma_name(struct vm_area_struct *vma)
{
return NULL;
}
static inline struct anon_vma_name *anon_vma_name_alloc(const char *name)
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
{
return NULL;
}
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static inline void anon_vma_name_get(struct anon_vma_name *anon_name) {}
static inline void anon_vma_name_put(struct anon_vma_name *anon_name) {}
static inline void dup_anon_vma_name(struct vm_area_struct *orig_vma,
struct vm_area_struct *new_vma) {}
static inline void free_anon_vma_name(struct vm_area_struct *vma) {}
static inline bool anon_vma_name_eq(struct anon_vma_name *anon_name1,
struct anon_vma_name *anon_name2)
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
{
return true;
}
2022-03-05 07:28:51 +03:00
mm: move anon_vma declarations to linux/mm_inline.h The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 01:06:07 +03:00
#endif /* CONFIG_ANON_VMA_NAME */
static inline void init_tlb_flush_pending(struct mm_struct *mm)
{
atomic_set(&mm->tlb_flush_pending, 0);
}
static inline void inc_tlb_flush_pending(struct mm_struct *mm)
{
atomic_inc(&mm->tlb_flush_pending);
/*
* The only time this value is relevant is when there are indeed pages
* to flush. And we'll only flush pages after changing them, which
* requires the PTL.
*
* So the ordering here is:
*
* atomic_inc(&mm->tlb_flush_pending);
* spin_lock(&ptl);
* ...
* set_pte_at();
* spin_unlock(&ptl);
*
* spin_lock(&ptl)
* mm_tlb_flush_pending();
* ....
* spin_unlock(&ptl);
*
* flush_tlb_range();
* atomic_dec(&mm->tlb_flush_pending);
*
* Where the increment if constrained by the PTL unlock, it thus
* ensures that the increment is visible if the PTE modification is
* visible. After all, if there is no PTE modification, nobody cares
* about TLB flushes either.
*
* This very much relies on users (mm_tlb_flush_pending() and
* mm_tlb_flush_nested()) only caring about _specific_ PTEs (and
* therefore specific PTLs), because with SPLIT_PTE_PTLOCKS and RCpc
* locks (PPC) the unlock of one doesn't order against the lock of
* another PTL.
*
* The decrement is ordered by the flush_tlb_range(), such that
* mm_tlb_flush_pending() will not return false unless all flushes have
* completed.
*/
}
static inline void dec_tlb_flush_pending(struct mm_struct *mm)
{
/*
* See inc_tlb_flush_pending().
*
* This cannot be smp_mb__before_atomic() because smp_mb() simply does
* not order against TLB invalidate completion, which is what we need.
*
* Therefore we must rely on tlb_flush_*() to guarantee order.
*/
atomic_dec(&mm->tlb_flush_pending);
}
static inline bool mm_tlb_flush_pending(struct mm_struct *mm)
{
/*
* Must be called after having acquired the PTL; orders against that
* PTLs release and therefore ensures that if we observe the modified
* PTE we must also observe the increment from inc_tlb_flush_pending().
*
* That is, it only guarantees to return true if there is a flush
* pending for _this_ PTL.
*/
return atomic_read(&mm->tlb_flush_pending);
}
static inline bool mm_tlb_flush_nested(struct mm_struct *mm)
{
/*
* Similar to mm_tlb_flush_pending(), we must have acquired the PTL
* for which there is a TLB flush pending in order to guarantee
* we've seen both that PTE modification and the increment.
*
* (no requirement on actually still holding the PTL, that is irrelevant)
*/
return atomic_read(&mm->tlb_flush_pending) > 1;
}
/*
* If this pte is wr-protected by uffd-wp in any form, arm the special pte to
* replace a none pte. NOTE! This should only be called when *pte is already
* cleared so we will never accidentally replace something valuable. Meanwhile
* none pte also means we are not demoting the pte so tlb flushed is not needed.
* E.g., when pte cleared the caller should have taken care of the tlb flush.
*
* Must be called with pgtable lock held so that no thread will see the none
* pte, and if they see it, they'll fault and serialize at the pgtable lock.
*
* This function is a no-op if PTE_MARKER_UFFD_WP is not enabled.
*/
static inline void
pte_install_uffd_wp_if_needed(struct vm_area_struct *vma, unsigned long addr,
pte_t *pte, pte_t pteval)
{
#ifdef CONFIG_PTE_MARKER_UFFD_WP
bool arm_uffd_pte = false;
/* The current status of the pte should be "cleared" before calling */
WARN_ON_ONCE(!pte_none(*pte));
if (vma_is_anonymous(vma) || !userfaultfd_wp(vma))
return;
/* A uffd-wp wr-protected normal pte */
if (unlikely(pte_present(pteval) && pte_uffd_wp(pteval)))
arm_uffd_pte = true;
/*
* A uffd-wp wr-protected swap pte. Note: this should even cover an
* existing pte marker with uffd-wp bit set.
*/
if (unlikely(pte_swp_uffd_wp_any(pteval)))
arm_uffd_pte = true;
if (unlikely(arm_uffd_pte))
set_pte_at(vma->vm_mm, addr, pte,
make_pte_marker(PTE_MARKER_UFFD_WP));
#endif
}
#endif