- 29 Jun, 2021 40 commits
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Liam Howlett authored
Use vma_lookup() to find the VMA at a specific address. As vma_lookup() will return NULL if the address is not within any VMA, the start address no longer needs to be validated. Link: https://lkml.kernel.org/r/20210521174745.2219620-19-Liam.Howlett@Oracle.comSigned-off-by:
Liam R. Howlett <Liam.Howlett@Oracle.com> Reviewed-by:
Laurent Dufour <ldufour@linux.ibm.com> Acked-by:
David Hildenbrand <david@redhat.com> Acked-by:
Davidlohr Bueso <dbueso@suse.de> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Liam Howlett authored
Use vma_lookup() to find the VMA at a specific address. As vma_lookup() will return NULL if the address is not within any VMA, the start address no longer needs to be validated. Link: https://lkml.kernel.org/r/20210521174745.2219620-18-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
Use vma_lookup() to find the VMA at a specific address. As vma_lookup() will return NULL if the address is not within any VMA, the start address no longer needs to be validated. Link: https://lkml.kernel.org/r/20210521174745.2219620-17-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
Use vma_lookup() to find the VMA at a specific address. As vma_lookup() will return NULL if the address is not within any VMA, the start address no longer needs to be validated. Link: https://lkml.kernel.org/r/20210521174745.2219620-16-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
vma_lookup() finds the vma of a specific address with a cleaner interface and is more readable. Link: https://lkml.kernel.org/r/20210521174745.2219620-15-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
Use vma_lookup() to find the VMA at a specific address. As vma_lookup() will return NULL if the address is not within any VMA, the start address no longer needs to be validated. Link: https://lkml.kernel.org/r/20210521174745.2219620-14-Liam.Howlett@Oracle.comSigned-off-by:
Alex Deucher <alexander.deucher@amd.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by:
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Liam Howlett authored
Use vma_lookup() to find the VMA at a specific address. As vma_lookup() will return NULL if the address is not within any VMA, the start address no longer needs to be validated. Link: https://lkml.kernel.org/r/20210521174745.2219620-13-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
vma_lookup() finds the vma of a specific address with a cleaner interface and is more readable. Link: https://lkml.kernel.org/r/20210521174745.2219620-12-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
vma_lookup() finds the vma of a specific address with a cleaner interface and is more readable. Link: https://lkml.kernel.org/r/20210521174745.2219620-11-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
Use vma_lookup() to find the VMA at a specific address. As vma_lookup() will return NULL if the address is not within any VMA, the start address no longer needs to be validated. Link: https://lkml.kernel.org/r/20210521174745.2219620-10-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
Use vma_lookup() to find the VMA at a specific address. As vma_lookup() will return NULL if the address is not within any VMA, the start address no longer needs to be validated. Link: https://lkml.kernel.org/r/20210521174745.2219620-9-Liam.Howlett@Oracle.comSigned-off-by:
Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by:
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Liam Howlett authored
Use vma_lookup() to find the VMA at a specific address. As vma_lookup() will return NULL if the address is not within any VMA, the start address no longer needs to be validated. Link: https://lkml.kernel.org/r/20210521174745.2219620-8-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
Using vma_lookup() removes the requirement to check if the address is within the returned vma. The code is easier to understand and more compact. Link: https://lkml.kernel.org/r/20210521174745.2219620-7-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
vma_lookup() finds the vma of a specific address with a cleaner interface and is more readable. Link: https://lkml.kernel.org/r/20210521174745.2219620-6-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
vma_lookup() finds the vma of a specific address with a cleaner interface and is more readable. Link: https://lkml.kernel.org/r/20210521174745.2219620-5-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
Use vma_lookup() to find the VMA at a specific address. As vma_lookup() will return NULL if the address is not within any VMA, the start address no longer needs to be validated. Link: https://lkml.kernel.org/r/20210521174745.2219620-4-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
vma_lookup() will look up the vma at a specific address. find_vma() will start the search for a specific address and continue upwards. This fixes an issue with the selftest as the returned vma may not be the newly created vma, but simply the vma at a higher address. objects Link: https://lkml.kernel.org/r/20210521174745.2219620-3-Liam.Howlett@Oracle.com Fixes: 6fedafac (drm/i915/selftests: Wrap vm_mmap() around GEM Signed-off-by:
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Liam Howlett authored
Patch series "mm: Add vma_lookup()", v2. Many places in the kernel use find_vma() to get a vma and then check the start address of the vma to ensure the next vma was not returned. Other places use the find_vma_intersection() call with add, addr + 1 as the range; looking for just the vma at a specific address. The third use of find_vma() is by developers who do not know that the function starts searching at the provided address upwards for the next vma. This results in a bug that is often overlooked for a long time. Adding the new vma_lookup() function will allow for cleaner code by removing the find_vma() calls which check limits, making find_vma_intersection() calls of a single address to be shorter, and potentially reduce the incorrect uses of find_vma(). This patch (of 22): Many places in the kernel use find_vma() to get a vma and then check the start address of the vma to ensure the next vma was not returned. Other places use the find_vma_intersection() call with add, addr + 1 as the range; looking for just the vma at a specific address. The third use of find_vma() is by developers who do not know that the function starts searching at the provided address upwards for the next vma. This results in a bug that is often overlooked for a long time. Adding the new vma_lookup() function will allow for cleaner code by removing the find_vma() calls which check limits, making find_vma_intersection() calls of a single address to be shorter, and potentially reduce the incorrect uses of find_vma(). Also change find_vma_intersection() comments and declaration to be of the correct length and add kernel documentation style comment. Link: https://lkml.kernel.org/r/20210521174745.2219620-1-Liam.Howlett@Oracle.com Link: https://lkml.kernel.org/r/20210521174745.2219620-2-Liam.Howlett@Oracle.comSigned-off-by:
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Liu Xiang authored
Fix the return value in comment of finish_mkwrite_fault(). Link: https://lkml.kernel.org/r/20210513093931.15234-1-liu.xiang@zlingsmart.comSigned-off-by:
Liu Xiang <liu.xiang@zlingsmart.com> Reviewed-by:
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Liam Howlett authored
Using find_vma_intersection() avoids the need for a temporary variable and makes the code cleaner. Link: https://lkml.kernel.org/r/20210511014328.2902782-1-Liam.Howlett@Oracle.comSigned-off-by:
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Liam Howlett authored
Both __do_munmap() and exit_mmap() unlock a range of VMAs using almost identical code blocks. Replace both blocks by a static inline function. [akpm@linux-foundation.org: tweak code layout] Link: https://lkml.kernel.org/r/20210510211021.2797427-1-Liam.Howlett@Oracle.comSigned-off-by:
Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by:
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Gonzalo Matias Juarez Tello authored
Logic of find_vma_intersection() is repeated in __do_munmap(). Also, prev is assigned a value before checking vma->vm_start >= end which might end up on a return statement making that assignment useless. Calling find_vma_intersection() checks that condition and returns NULL if no vma is found, hence only the !vma check is needed in __do_munmap(). Link: https://lkml.kernel.org/r/20210409162129.18313-1-gmjuareztello@gmail.comSigned-off-by:
Gonzalo Matias Juarez Tello <gmjuareztello@gmail.com> Reviewed-by:
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David Hildenbrand authored
Let's also remove masking off MAP_EXECUTABLE from ksys_mmap_pgoff(): the last in-tree occurrence of MAP_EXECUTABLE is now in LEGACY_MAP_MASK, which accepts the flag e.g., for MAP_SHARED_VALIDATE; however, the flag is ignored throughout the kernel now. Add a comment to LEGACY_MAP_MASK stating that MAP_EXECUTABLE is ignored. Link: https://lkml.kernel.org/r/20210421093453.6904-4-david@redhat.comSigned-off-by:
"Eric W. Biederman" <ebiederm@xmission.com> Reviewed-by:
Kees Cook <keescook@chromium.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Feng Tang <feng.tang@intel.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kevin Brodsky <Kevin.Brodsky@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
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David Hildenbrand authored
Ever since commit e9714acf ("mm: kill vma flag VM_EXECUTABLE and mm->num_exe_file_vmas"), VM_EXECUTABLE is gone and MAP_EXECUTABLE is essentially completely ignored. Let's remove all usage of MAP_EXECUTABLE. [akpm@linux-foundation.org: fix blooper in fs/binfmt_aout.c. per David] Link: https://lkml.kernel.org/r/20210421093453.6904-3-david@redhat.comSigned-off-by:
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David Hildenbrand authored
Patch series "perf/binfmt/mm: remove in-tree usage of MAP_EXECUTABLE". Stumbling over the history of MAP_EXECUTABLE, I noticed that we still have some in-tree users that we can get rid of. This patch (of 3): Before commit e9714acf ("mm: kill vma flag VM_EXECUTABLE and mm->num_exe_file_vmas"), VM_EXECUTABLE indicated MAP_EXECUTABLE. MAP_EXECUTABLE is nowadays essentially ignored by the kernel and does not relate to VM_MAYEXEC. Link: https://lkml.kernel.org/r/20210421093453.6904-1-david@redhat.com Link: https://lkml.kernel.org/r/20210421093453.6904-2-david@redhat.com Fixes: f972eb63 ("perf: Pass protection and flags bits through mmap2 interface") Signed-off-by:
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Huilong Deng authored
Macros should not use a trailing semicolon. Link: https://lkml.kernel.org/r/20210614091530.22117-1-denghuilong@cdjrlc.comSigned-off-by:
Huilong Deng <denghuilong@cdjrlc.com> Reviewed-by:
Shakeel Butt <shakeelb@google.com> Cc: Roman Gushchin <guro@fb.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by:
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Dan Schatzberg authored
The current code only associates with the existing blkcg when aio is used to access the backing file. This patch covers all types of i/o to the backing file and also associates the memcg so if the backing file is on tmpfs, memory is charged appropriately. This patch also exports cgroup_get_e_css and int_active_memcg so it can be used by the loop module. Link: https://lkml.kernel.org/r/20210610173944.1203706-4-schatzberg.dan@gmail.comSigned-off-by:
Dan Schatzberg <schatzberg.dan@gmail.com> Acked-by:
Johannes Weiner <hannes@cmpxchg.org> Acked-by:
Jens Axboe <axboe@kernel.dk> Cc: Chris Down <chris@chrisdown.name> Cc: Michal Hocko <mhocko@suse.com> Cc: Ming Lei <ming.lei@redhat.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by:
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Dan Schatzberg authored
set_active_memcg() worked for kernel allocations but was silently ignored for user pages. This patch establishes a precedence order for who gets charged: 1. If there is a memcg associated with the page already, that memcg is charged. This happens during swapin. 2. If an explicit mm is passed, mm->memcg is charged. This happens during page faults, which can be triggered in remote VMs (eg gup). 3. Otherwise consult the current process context. If there is an active_memcg, use that. Otherwise, current->mm->memcg. Previously, if a NULL mm was passed to mem_cgroup_charge (case 3) it would always charge the root cgroup. Now it looks up the active_memcg first (falling back to charging the root cgroup if not set). Link: https://lkml.kernel.org/r/20210610173944.1203706-3-schatzberg.dan@gmail.comSigned-off-by:
Tejun Heo <tj@kernel.org> Acked-by:
Chris Down <chris@chrisdown.name> Acked-by:
Michal Koutný <mkoutny@suse.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Ming Lei <ming.lei@redhat.com> Signed-off-by:
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Dan Schatzberg authored
Patch series "Charge loop device i/o to issuing cgroup", v14. The loop device runs all i/o to the backing file on a separate kworker thread which results in all i/o being charged to the root cgroup. This allows a loop device to be used to trivially bypass resource limits and other policy. This patch series fixes this gap in accounting. A simple script to demonstrate this behavior on cgroupv2 machine: ''' #!/bin/bash set -e CGROUP=/sys/fs/cgroup/test.slice LOOP_DEV=/dev/loop0 if [[ ! -d $CGROUP ]] then sudo mkdir $CGROUP fi grep oom_kill $CGROUP/memory.events # Set a memory limit, write more than that limit to tmpfs -> OOM kill sudo unshare -m bash -c " echo \$\$ > $CGROUP/cgroup.procs; echo 0 > $CGROUP/memory.swap.max; echo 64M > $CGROUP/memory.max; mount -t tmpfs -o size=512m tmpfs /tmp; dd if=/dev/zero of=/tmp/file bs=1M count=256" || true grep oom_kill $CGROUP/memory.events # Set a memory limit, write more than that limit through loopback # device -> no OOM kill sudo unshare -m bash -c " echo \$\$ > $CGROUP/cgroup.procs; echo 0 > $CGROUP/memory.swap.max; echo 64M > $CGROUP/memory.max; mount -t tmpfs -o size=512m tmpfs /tmp; truncate -s 512m /tmp/backing_file losetup $LOOP_DEV /tmp/backing_file dd if=/dev/zero of=$LOOP_DEV bs=1M count=256; losetup -D $LOOP_DEV" || true grep oom_kill $CGROUP/memory.events ''' Naively charging cgroups could result in priority inversions through the single kworker thread in the case where multiple cgroups are reading/writing to the same loop device. This patch series does some minor modification to the loop driver so that each cgroup can make forward progress independently to avoid this inversion. With this patch series applied, the above script triggers OOM kills when writing through the loop device as expected. This patch (of 3): Existing uses of loop device may have multiple cgroups reading/writing to the same device. Simply charging resources for I/O to the backing file could result in priority inversion where one cgroup gets synchronously blocked, holding up all other I/O to the loop device. In order to avoid this priority inversion, we use a single workqueue where each work item is a "struct loop_worker" which contains a queue of struct loop_cmds to issue. The loop device maintains a tree mapping blk css_id -> loop_worker. This allows each cgroup to independently make forward progress issuing I/O to the backing file. There is also a single queue for I/O associated with the rootcg which can be used in cases of extreme memory shortage where we cannot allocate a loop_worker. The locking for the tree and queues is fairly heavy handed - we acquire a per-loop-device spinlock any time either is accessed. The existing implementation serializes all I/O through a single thread anyways, so I don't believe this is any worse. [colin.king@canonical.com: fixes] Link: https://lkml.kernel.org/r/20210610173944.1203706-1-schatzberg.dan@gmail.com Link: https://lkml.kernel.org/r/20210610173944.1203706-2-schatzberg.dan@gmail.comSigned-off-by:Ming Lei <ming.lei@redhat.com> Acked-by:
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wenhuizhang authored
Change deprecated zero-length-and-one-element-arrays into flexible array member.Zero-length and one-element arrays detected by Lukas's CodeChecker. Zero/one element arrays cause undefined behaviours if sizeof() used. Link: https://lkml.kernel.org/r/20210518200910.29912-1-wenhui@gwmail.gwu.eduSigned-off-by:
wenhuizhang <wenhui@gwmail.gwu.edu> Reviewed-by:
Muchun Song <songmuchun@bytedance.com> Acked-by:
Michal Hocko <mhocko@suse.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Roman Gushchin <guro@fb.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Alex Shi <alexs@kernel.org> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Wei Yang <richard.weiyang@gmail.com> Signed-off-by:
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Muchun Song authored
The noinline_for_stack is introduced by commit 66635629 ("vmscan: set up pagevec as late as possible in shrink_inactive_list()"), its purpose is to delay the allocation of pagevec as late as possible to save stack memory. But the commit 2bcf8879 ("mm: take pagevecs off reclaim stack") replace pagevecs by lists of pages_to_free. So we do not need noinline_for_stack, just remove it (let the compiler decide whether to inline). Link: https://lkml.kernel.org/r/20210417043538.9793-9-songmuchun@bytedance.comSigned-off-by:
Roman Gushchin <guro@fb.com> Reviewed-by:
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Muchun Song authored
The css_set_lock is used to guard the list of inherited objcgs. So there is no need to uncharge kernel memory under css_set_lock. Just move it out of the lock. Link: https://lkml.kernel.org/r/20210417043538.9793-8-songmuchun@bytedance.comSigned-off-by:
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Muchun Song authored
The obj_cgroup_release() and memcg_reparent_objcgs() are serialized by the css_set_lock. We do not need to care about objcg->memcg being released in the process of obj_cgroup_release(). So there is no need to pin memcg before releasing objcg. Remove those pinning logic to simplfy the code. There are only two places that modifies the objcg->memcg. One is the initialization to objcg->memcg in the memcg_online_kmem(), another is objcgs reparenting in the memcg_reparent_objcgs(). It is also impossible for the two to run in parallel. So xchg() is unnecessary and it is enough to use WRITE_ONCE(). Link: https://lkml.kernel.org/r/20210417043538.9793-7-songmuchun@bytedance.comSigned-off-by:
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Muchun Song authored
lruvec_holds_page_lru_lock() doesn't check anything about locking and is used to check whether the page belongs to the lruvec. So rename it to page_matches_lruvec(). Link: https://lkml.kernel.org/r/20210417043538.9793-6-songmuchun@bytedance.comSigned-off-by:
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Muchun Song authored
We already have a helper lruvec_memcg() to get the memcg from lruvec, we do not need to do it ourselves in the lruvec_holds_page_lru_lock(). So use lruvec_memcg() instead. And if mem_cgroup_disabled() returns false, the page_memcg(page) (the LRU pages) cannot be NULL. So remove the odd logic of "memcg = page_memcg(page) ? : root_mem_cgroup". And use lruvec_pgdat to simplify the code. We can have a single definition for this function that works for !CONFIG_MEMCG, CONFIG_MEMCG + mem_cgroup_disabled() and CONFIG_MEMCG. Link: https://lkml.kernel.org/r/20210417043538.9793-5-songmuchun@bytedance.comSigned-off-by:
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Muchun Song authored
All the callers of mem_cgroup_page_lruvec() just pass page_pgdat(page) as the 2nd parameter to it (except isolate_migratepages_block()). But for isolate_migratepages_block(), the page_pgdat(page) is also equal to the local variable of @pgdat. So mem_cgroup_page_lruvec() do not need the pgdat parameter. Just remove it to simplify the code. Link: https://lkml.kernel.org/r/20210417043538.9793-4-songmuchun@bytedance.comSigned-off-by:
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Muchun Song authored
When mm is NULL, we do not need to hold rcu lock and call css_tryget for the root memcg. And we also do not need to check !mm in every loop of while. So bail out early when !mm. Link: https://lkml.kernel.org/r/20210417043538.9793-3-songmuchun@bytedance.comSigned-off-by:
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Muchun Song authored
Patch series "memcontrol code cleanup and simplification", v3. This patch (of 8): The pages aren't accounted at the root level, so do not charge the page to the root memcg in page replacement. Although we do not display the value (mem_cgroup_usage) so there shouldn't be any actual problem, but there is a WARN_ON_ONCE in the page_counter_cancel(). Who knows if it will trigger? So it is better to fix it. Link: https://lkml.kernel.org/r/20210417043538.9793-1-songmuchun@bytedance.com Link: https://lkml.kernel.org/r/20210417043538.9793-2-songmuchun@bytedance.comSigned-off-by:
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Muchun Song authored
The below scenario can cause the page counters of the root_mem_cgroup to be out of balance. CPU0: CPU1: objcg = get_obj_cgroup_from_current() obj_cgroup_charge_pages(objcg) memcg_reparent_objcgs() // reparent to root_mem_cgroup WRITE_ONCE(iter->memcg, parent) // memcg == root_mem_cgroup memcg = get_mem_cgroup_from_objcg(objcg) // do not charge to the root_mem_cgroup try_charge(memcg) obj_cgroup_uncharge_pages(objcg) memcg = get_mem_cgroup_from_objcg(objcg) // uncharge from the root_mem_cgroup refill_stock(memcg) drain_stock(memcg) page_counter_uncharge(&memcg->memory) get_obj_cgroup_from_current() never returns a root_mem_cgroup's objcg, so we never explicitly charge the root_mem_cgroup. And it's not going to change. It's all about a race when we got an obj_cgroup pointing at some non-root memcg, but before we were able to charge it, the cgroup was gone, objcg was reparented to the root and so we're skipping the charging. Then we store the objcg pointer and later use to uncharge the root_mem_cgroup. This can cause the page counter to be less than the actual value. Although we do not display the value (mem_cgroup_usage) so there shouldn't be any actual problem, but there is a WARN_ON_ONCE in the page_counter_cancel(). Who knows if it will trigger? So it is better to fix it. Link: https://lkml.kernel.org/r/20210425075410.19255-1-songmuchun@bytedance.comSigned-off-by: -
Waiman Long authored
The KMALLOC_NORMAL (kmalloc-<n>) caches are for unaccounted objects only when CONFIG_MEMCG_KMEM is enabled. To make sure that this condition remains true, we will have to prevent KMALOC_NORMAL caches to merge with other kmem caches. This is now done by setting its refcount to -1 right after its creation. Link: https://lkml.kernel.org/r/20210505200610.13943-4-longman@redhat.comSigned-off-by:
Waiman Long <longman@redhat.com> Suggested-by:
Vlastimil Babka <vbabka@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Signed-off-by:
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