The check for root memcg will be done in wb_get_lookup(), so remove the
redundant one to simplify the code.
Link: https://lkml.kernel.org/r/20230808084431.1632934-1-alexjlzheng@tencent.com
Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since commit 0bb488498c ("mm: zswap: remove zswap_header"), the 'offset'
has been replaced by swpentry, update the comment for it, and also add
comment for 'objcg'.
Link: https://lkml.kernel.org/r/20230808062056.292950-1-xiujianfeng@huaweicloud.com
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
Acked-by: Nhat Pham <nphamcs@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
It is better to not expose too many internal variables of memtest,
add a helper memtest_report_meminfo() to show memtest results.
Link: https://lkml.kernel.org/r/20230808033359.174986-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Tomas Mudrunka <tomas.mudrunka@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
It's more readable to use helper macro BITS_PER_LONG and BITS_PER_BYTE.
No functional change intended.
Link: https://lkml.kernel.org/r/20230807023528.325191-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
It's more convenient to use helper macro llist_for_each_entry_safe().
No functional change intended.
Link: https://lkml.kernel.org/r/20230807114125.3440802-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Otherwise the kernel ends up with multiple copies:
$ nm vmlinux | grep dummy_vm_ops
ffffffff81e4ea00 d dummy_vm_ops.2
ffffffff81e11760 d dummy_vm_ops.254
ffffffff81e406e0 d dummy_vm_ops.4
ffffffff81e3c780 d dummy_vm_ops.7
While here prefix it with vma_.
Link: https://lkml.kernel.org/r/20230806231611.1395735-1-mjguzik@gmail.com
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
vma_prepare() is currently the central place where vmas are being locked
before vma_complete() applies changes to them. While this is convenient,
it also obscures vma locking and makes it harder to follow the locking
rules. Move vma locking out of vma_prepare() and take vma locks
explicitly at the locations where vmas are being modified. Move vma
locking and replace it with an assertion inside dup_anon_vma() to further
clarify the locking pattern inside vma_merge().
Link: https://lkml.kernel.org/r/20230804152724.3090321-7-surenb@google.com
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Suggested-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
While it's not strictly necessary to lock a newly created vma before
adding it into the vma tree (as long as no further changes are performed
to it), it seems like a good policy to lock it and prevent accidental
changes after it becomes visible to the page faults. Lock the vma before
adding it into the vma tree.
[akpm@linux-foundation.org: fix reject fixing in vma_link(), per Jann]
Link: https://lkml.kernel.org/r/20230804152724.3090321-6-surenb@google.com
Suggested-by: Jann Horn <jannh@google.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Implicit vma locking inside vm_flags_reset() and vm_flags_reset_once() is
not obvious and makes it hard to understand where vma locking is happening.
Also in some cases (like in dup_userfaultfd()) vma should be locked earlier
than vma_flags modification. To make locking more visible, change these
functions to assert that the vma write lock is taken and explicitly lock
the vma beforehand. Fix userfaultfd functions which should lock the vma
earlier.
Link: https://lkml.kernel.org/r/20230804152724.3090321-5-surenb@google.com
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Vma write lock assertion always includes mmap write lock assertion and
additional vma lock checks when per-VMA locks are enabled. Replace
weaker mmap_assert_write_locked() assertions with stronger
vma_assert_write_locked() ones when we are operating on a vma which
is expected to be locked.
Link: https://lkml.kernel.org/r/20230804152724.3090321-4-surenb@google.com
Suggested-by: Jann Horn <jannh@google.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use helper macro K() to improve code readability. No functional
modification involved.
Link: https://lkml.kernel.org/r/20230804012559.2617515-8-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use helper macro K() to improve code readability. No functional
modification involved.
Link: https://lkml.kernel.org/r/20230804012559.2617515-7-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use helper macro K() to improve code readability. No functional
modification involved.
Link: https://lkml.kernel.org/r/20230804012559.2617515-6-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use helper macro K() to improve code readability. No functional
modification involved.
Link: https://lkml.kernel.org/r/20230804012559.2617515-5-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use helper macro K() to improve code readability. No functional
modification involved.
Link: https://lkml.kernel.org/r/20230804012559.2617515-4-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use helper macro K() to improve code readability. No functional
modification involved.
Link: https://lkml.kernel.org/r/20230804012559.2617515-3-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "cleanup with helper macro K()".
Use helper macro K() to improve code readability. No functional
modification involved. Remove redundant K() macro definition.
This patch (of 7):
Since commit eb8589b4f8 ("mm: move mem_init_print_info() to mm_init.c"),
the K() macro definition has been moved to mm/internal.h. Therefore, the
definitions in mm/memcontrol.c, mm/backing-dev.c and mm/oom_kill.c are
redundant. Drop redundant definitions.
[akpm@linux-foundation.org: oom_kill.c: remove "#undef K", per Kefeng]
Link: https://lkml.kernel.org/r/20230804012559.2617515-1-zhangpeng362@huawei.com
Link: https://lkml.kernel.org/r/20230804012559.2617515-2-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
For system with kernelcore=mirror enabled while no mirrored memory is
reported by efi. This could lead to kernel OOM during startup since all
memory beside zone DMA are in the movable zone and this prevents the
kernel to use it.
Zone DMA/DMA32 initialization is independent of mirrored memory and their
max pfn is set in zone_sizes_init(). Since kernel can fallback to zone
DMA/DMA32 if there is no memory in zone Normal, these zones are seen as
mirrored memory no mather their memory attributes are.
To solve this problem, disable kernelcore=mirror when there is no real
mirrored memory exists.
Link: https://lkml.kernel.org/r/20230802072328.2107981-1-mawupeng1@huawei.com
Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>
Suggested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Suggested-by: Mike Rapoport <rppt@kernel.org>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Levi Yun <ppbuk5246@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Keep the same logic as update_pageblock_skip, only set skip if
no_set_skip_hint is false which is more reasonable.
Link: https://lkml.kernel.org/r/20230804110454.2935878-9-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove unnecessary return for void function
Link: https://lkml.kernel.org/r/20230804110454.2935878-8-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Commit e380bebe47 ("mm, compaction: keep migration source private to a
single compaction instance") moved update of async and sync
compact_cached_migrate_pfn from update_pageblock_skip to
update_cached_migrate but left the comment behind. Move the relevant
comment to correct this.
Link: https://lkml.kernel.org/r/20230804110454.2935878-6-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
After 90ed667c03 ("Revert "Revert "mm/compaction: fix set skip in
fast_find_migrateblock"""), we remove skip set in fast_find_migrateblock.
Correct comment that fast_find_block is used to avoid isolation_suitable
check for pageblock returned from fast_find_migrateblock because
fast_find_migrateblock will mark found pageblock skipped.
Instead, comment that fast_find_block is used to avoid a redundant check
of fast found pageblock which is already checked skip flag inside
fast_find_migrateblock.
Link: https://lkml.kernel.org/r/20230804110454.2935878-5-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Move migrate_pfn to page block end when block is marked skip to avoid
unnecessary scan retry of that block from upper caller. For example,
compact_zone may wrongly rescan skip page block with finish_pageblock
set as following:
1. cc->migrate point to the start of page block
2. compact_zone record last_migrated_pfn to cc->migrate
3. compact_zone->isolate_migratepages->isolate_migratepages_block
tries to scan the block. The low_pfn maybe moved forward to middle of
block because of free pages at beginning of block.
4. we find first lru page could be isolated but block was exclusive
marked skip.
5. abort isolate_migratepages_block and make cc->migrate_pfn point to
found lru page at middle of block.
6. compact_zone find cc->migrate_pfn and last_migrated_pfn are in the
same block and wrongly rescan the block with finish_pageblock set.
Link: https://lkml.kernel.org/r/20230804110454.2935878-4-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We record start pfn of last isolated page block with last_migrated_pfn. And
then:
1. We check if we mark the page block skip for exclusive access in
isolate_migratepages_block by test if next migrate pfn is still in last
isolated page block. If so, we will set finish_pageblock to do the
rescan.
2. We check if a full cc->order block is scanned by test if last scan
range passes the cc->order block boundary. If so, we flush the pages
were freed.
We treat cc->migrate_pfn before isolate_migratepages as the start pfn of
last isolated page range. However, we always align migrate_pfn to page
block or move to another page block in fast_find_migrateblock or in
linearly scan forward in isolate_migratepages before do page isolation in
isolate_migratepages_block.
Update last_migrated_pfn with pageblock_start_pfn(cc->migrate_pfn - 1)
after scan to correctly set start pfn of last isolated page range. To
avoid that:
1. Miss a rescan with finish_pageblock set as last_migrate_pfn does
not point to right pageblock and the migrate will not be in pageblock
of last_migrate_pfn as it should be.
2. Wrongly issue flush by test cc->order block boundary with wrong
last_migrate_pfn.
Link: https://lkml.kernel.org/r/20230804110454.2935878-3-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There are no modules using mm_kobj, so do not export it.
Link: https://lkml.kernel.org/r/2023080436-algebra-cabana-417d@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Archs may need to do special things when flushing hugepage tlb, so use the
more applicable flush_hugetlb_tlb_range() instead of flush_tlb_range().
Link: https://lkml.kernel.org/r/20230801023145.17026-2-wangkefeng.wang@huawei.com
Fixes: 550a7d60bd ("mm, hugepages: add mremap() support for hugepage backed vma")
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Barry Song <21cnbao@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Will Deacon <will@kernel.org>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There is no behavior change to remove "else continue" code at end of scan
loop. Just remove it to make code cleaner.
Link: https://lkml.kernel.org/r/20230803094901.2915942-5-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Kemeng Shi <shikemeng@huawei.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The cursor is only used for page forward currently. We can simply move
page forward directly to remove unnecessary cursor.
Link: https://lkml.kernel.org/r/20230803094901.2915942-4-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Kemeng Shi <shikemeng@huawei.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Merge the end_pfn boundary check for single page block forward and
multiple page blocks forward to avoid do twice boundary check for multiple
page blocks forward.
Link: https://lkml.kernel.org/r/20230803094901.2915942-3-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Fixes and cleanups to compaction", v2.
This series contains random fixes and cleanups to free page isolation in
compaction. This is based on another compact series[1]. More details can
be found in respective patches.
This patch (of 4):
We will set skip to page block of block_start_pfn, it's more reasonable to
set compact_cached_free_pfn to page block before the block_start_pfn.
Link: https://lkml.kernel.org/r/20230803094901.2915942-1-shikemeng@huaweicloud.com
Link: https://lkml.kernel.org/r/20230803094901.2915942-2-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Kemeng Shi <shikemeng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The correct function name is obj_cgroup_may_zswap(). Correct the comment.
Link: https://lkml.kernel.org/r/20230803120021.762279-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since commit 5d0a661d80 ("mm/page_alloc: use only one PCP list for
THP-sized allocations"), local variable base is just as same as order. So
remove it. No functional change intended.
Link: https://lkml.kernel.org/r/20230803114934.693989-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This code is already duplicated six times, use helper function
put_z3fold_locked() to release z3fold page instead of open code it to help
improve code readability a bit. And add put_z3fold_locked_list() helper
function to be consistent with it. No functional change involved.
Link: https://lkml.kernel.org/r/20230803113824.886413-1-ruanjinjie@huawei.com
Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Extend DAMON sysfs interface to support the DAMON monitoring target based
DAMOS filter. Users can use it via writing 'target' to the filter's
'type' file and specifying the index of the target from the corresponding
DAMON context's monitoring targets list to 'target_idx' sysfs file.
Link: https://lkml.kernel.org/r/20230802214312.110532-10-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
One DAMON context can have multiple monitoring targets, and DAMOS schemes
are applied to all targets. In some cases, users need to apply different
scheme to different targets. Retrieving monitoring results via DAMON
sysfs interface' 'tried_regions' directory could be one good example.
Also, there could be cases that cgroup DAMOS filter is not enough. All
such use cases can be worked around by having multiple DAMON contexts
having only single target, but it is inefficient in terms of resource
usage, thogh the overhead is not estimated to be huge.
Implement DAMON monitoring target based DAMOS filter for the case. Like
address range target DAMOS filter, handle these filters in the DAMON core
layer, since it is more efficient than doing in operations set layer.
This also means that regions that filtered out by monitoring target type
DAMOS filters are counted as not tried by the scheme. Hence, target
granularity monitoring results retrieval via DAMON sysfs interface becomes
available.
Link: https://lkml.kernel.org/r/20230802214312.110532-9-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Implement a kunit test for the core of address range DAMOS filter
handling, namely __damos_filter_out(). The test especially focus on
regions that overlap with given filter's target address range.
Link: https://lkml.kernel.org/r/20230802214312.110532-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Extend DAMON sysfs interface to support address range based DAMOS filters,
by adding a special keyword for the filter/<N>/type file, namely 'addr',
and two files under filter/<N>/ for specifying the start and the end
addresses of the range, namely 'addr_start' and 'addr_end'.
Link: https://lkml.kernel.org/r/20230802214312.110532-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Extend DAMOS filters for address ranges and DAMON monitoring
targets"
There are use cases that need to apply DAMOS schemes to specific address
ranges or DAMON monitoring targets. NUMA nodes in the physical address
space, special memory objects in the virtual address space, and monitoring
target specific efficient monitoring results snapshot retrieval could be
examples of such use cases. This patchset extends DAMOS filters feature
for such cases, by implementing two more filter types, namely address
ranges and DAMON monitoring types.
Patches sequence
----------------
The first seven patches are for the address ranges based DAMOS filter.
The first patch implements the filter feature and expose it via DAMON
kernel API. The second patch further expose the feature to users via
DAMON sysfs interface. The third and fourth patches implement unit tests
and selftests for the feature. Three patches (fifth to seventh) updating
the documents follow.
The following six patches are for the DAMON monitoring target based DAMOS
filter. The eighth patch implements the feature in the core layer and
expose it via DAMON's kernel API. The ninth patch further expose it to
users via DAMON sysfs interface. Tenth patch add a selftest, and two
patches (eleventh and twelfth) update documents.
[1] https://lore.kernel.org/damon/20230728203444.70703-1-sj@kernel.org/
This patch (of 13):
Users can know special characteristic of specific address ranges. NUMA
nodes or special objects or buffers in virtual address space could be such
examples. For such cases, DAMOS schemes could required to be applied to
only specific address ranges. Implement yet another type of DAMOS filter
for the purpose.
Note that the existing filter types, namely anon pages and memcg DAMOS
filters needed page level type check. Because such check can be done
efficiently in the opertions set layer, those filters are handled in
operations set layer. Specifically, only paddr operations set
implementation supports these filters. Also, because statistics counting
is done in the DAMON core layer, the regions that filtered out by these
filters are counted as tried but failed to the statistics.
Unlike those, address range based filters can efficiently handled in the
core layer. Hence, do the handling in the layer, and count the regions
that filtered out by those as the scheme has not tried for the region.
This difference should clearly documented.
Link: https://lkml.kernel.org/r/20230802214312.110532-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20230802214312.110532-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Using tried_regions/total_bytes file, users can efficiently retrieve the
total size of memory regions having specific access pattern. However,
DAMON sysfs interface in kernel still populates all the infomration on the
tried_regions subdirectories. That means the kernel part overhead for the
construction of tried regions directories still exists. To remove the
overhead, implement yet another command input for 'state' DAMON sysfs
file. Writing the input to the file makes DAMON sysfs interface to update
only the total_bytes file.
Link: https://lkml.kernel.org/r/20230802213222.109841-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm/damon/sysfs-schemes: implement DAMOS tried total bytes
file".
The tried_regions directory of DAMON sysfs interface is useful for
retrieving monitoring results snapshot or DAMOS debugging. However, for
common use case that need to monitor only the total size of the scheme
tried regions (e.g., monitoring working set size), the kernel overhead for
directory construction and user overhead for reading the content could be
high if the number of monitoring region is not small. This patchset
implements DAMON sysfs files for efficient support of the use case.
The first patch implements the sysfs file to reduce the user space
overhead, and the second patch implements a command for reducing the
kernel space overhead.
The third patch adds a selftest for the new file, and following two
patches update documents.
[1] https://lore.kernel.org/damon/20230728201817.70602-1-sj@kernel.org/
This patch (of 5):
The tried_regions directory can be used for retrieving the monitoring
results snapshot for regions of specific access pattern, by setting the
scheme's action as 'stat' and the access pattern as required. While the
interface provides every detail of the monitoring results, some use cases
including working set size monitoring requires only the total size of the
regions. For such cases, users should read all the information and
calculate the total size of the regions. However, it could incur high
overhead if the number of regions is high. Add a file for retrieving only
the information, namely 'total_bytes' file. It allows users to get the
total size by reading only the file.
Link: https://lkml.kernel.org/r/20230802213222.109841-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20230802213222.109841-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
walk->can_swap might be invalid since it's not guaranteed to be
initialized for the particular lruvec. Instead deduce it from the folio
type (anon/file).
Link: https://lkml.kernel.org/r/20230802025606.346758-3-kaleshsingh@google.com
Fixes: 018ee47f14 ("mm: multi-gen LRU: exploit locality in rmap")
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> [mediatek]
Tested-by: Charan Teja Kalla <quic_charante@quicinc.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Aneesh Kumar K V <aneesh.kumar@linux.ibm.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Oleksandr Natalenko <oleksandr@natalenko.name>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Steven Barrett <steven@liquorix.net>
Cc: Suleiman Souhlal <suleiman@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
inc_max_seq() will try to inc_min_seq() if nr_gens == MAX_NR_GENS. This
is because the generations are reused (the last oldest now empty
generation will become the next youngest generation).
inc_min_seq() is retried until successful, dropping the lru_lock
and yielding the CPU on each failure, and retaking the lock before
trying again:
while (!inc_min_seq(lruvec, type, can_swap)) {
spin_unlock_irq(&lruvec->lru_lock);
cond_resched();
spin_lock_irq(&lruvec->lru_lock);
}
However, the initial condition that required incrementing the min_seq
(nr_gens == MAX_NR_GENS) is not retested. This can change by another
call to inc_max_seq() from run_aging() with force_scan=true from the
debugfs interface.
Since the eviction stalls when the nr_gens == MIN_NR_GENS, avoid
unnecessarily incrementing the min_seq by rechecking the number of
generations before each attempt.
This issue was uncovered in previous discussion on the list by Yu Zhao
and Aneesh Kumar [1].
[1] https://lore.kernel.org/linux-mm/CAOUHufbO7CaVm=xjEb1avDhHVvnC8pJmGyKcFf2iY_dpf+zR3w@mail.gmail.com/
Link: https://lkml.kernel.org/r/20230802025606.346758-2-kaleshsingh@google.com
Fixes: d6c3af7d8a ("mm: multi-gen LRU: debugfs interface")
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> [mediatek]
Tested-by: Charan Teja Kalla <quic_charante@quicinc.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Aneesh Kumar K V <aneesh.kumar@linux.ibm.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Oleksandr Natalenko <oleksandr@natalenko.name>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Steven Barrett <steven@liquorix.net>
Cc: Suleiman Souhlal <suleiman@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
MGLRU has a LRU list for each zone for each type (anon/file) in each
generation:
long nr_pages[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES];
The min_seq (oldest generation) can progress independently for each
type but the max_seq (youngest generation) is shared for both anon and
file. This is to maintain a common frame of reference.
In order for eviction to advance the min_seq of a type, all the per-zone
lists in the oldest generation of that type must be empty.
The eviction logic only considers pages from eligible zones for
eviction or promotion.
scan_folios() {
...
for (zone = sc->reclaim_idx; zone >= 0; zone--) {
...
sort_folio(); // Promote
...
isolate_folio(); // Evict
}
...
}
Consider the system has the movable zone configured and default 4
generations. The current state of the system is as shown below
(only illustrating one type for simplicity):
Type: ANON
Zone DMA32 Normal Movable Device
Gen 0 0 0 4GB 0
Gen 1 0 1GB 1MB 0
Gen 2 1MB 4GB 1MB 0
Gen 3 1MB 1MB 1MB 0
Now consider there is a GFP_KERNEL allocation request (eligible zone
index <= Normal), evict_folios() will return without doing any work
since there are no pages to scan in the eligible zones of the oldest
generation. Reclaim won't make progress until triggered from a ZONE_MOVABLE
allocation request; which may not happen soon if there is a lot of free
memory in the movable zone. This can lead to OOM kills, although there
is 1GB pages in the Normal zone of Gen 1 that we have not yet tried to
reclaim.
This issue is not seen in the conventional active/inactive LRU since
there are no per-zone lists.
If there are no (not enough) folios to scan in the eligible zones, move
folios from ineligible zone (zone_index > reclaim_index) to the next
generation. This allows for the progression of min_seq and reclaiming
from the next generation (Gen 1).
Qualcomm, Mediatek and raspberrypi [1] discovered this issue independently.
[1] https://github.com/raspberrypi/linux/issues/5395
Link: https://lkml.kernel.org/r/20230802025606.346758-1-kaleshsingh@google.com
Fixes: ac35a49023 ("mm: multi-gen LRU: minimal implementation")
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reported-by: Charan Teja Kalla <quic_charante@quicinc.com>
Reported-by: Lecopzer Chen <lecopzer.chen@mediatek.com>
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> [mediatek]
Tested-by: Charan Teja Kalla <quic_charante@quicinc.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Oleksandr Natalenko <oleksandr@natalenko.name>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Steven Barrett <steven@liquorix.net>
Cc: Suleiman Souhlal <suleiman@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Aneesh Kumar K V <aneesh.kumar@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Before commit f53af4285d ("mm: vmscan: fix extreme overreclaim and swap
floods"), proactive reclaim will extreme overreclaim sometimes. But
proactive reclaim still inaccurate and some extent overreclaim.
Problematic case is easy to construct. Allocate lots of anonymous memory
(e.g., 20G) in a memcg, then swapping by writing memory.recalim and there
is a certain probability of overreclaim. For example, request 1G by
writing memory.reclaim will eventually reclaim 1.7G or other values more
than 1G.
The reason is that reclaimer may have already reclaimed part of requested
memory in one loop, but before adjust sc->nr_to_reclaim in outer loop,
call shrink_lruvec() again will still follow the current sc->nr_to_reclaim
to work. It will eventually lead to overreclaim. In theory, the amount
of reclaimed would be in [request, 2 * request).
Reclaimer usually tends to reclaim more than request. But either direct
or kswapd reclaim have much smaller nr_to_reclaim targets, so it is less
noticeable and not have much impact.
Proactive reclaim can usually come in with a larger value, so the error is
difficult to ignore. Considering proactive reclaim is usually low
frequency, handle the batching into smaller chunks is a better approach.
Link: https://lkml.kernel.org/r/20230721014116.3388-1-yangyifei03@kuaishou.com
Signed-off-by: Efly Young <yangyifei03@kuaishou.com>
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
damos_new_filter() was having a bug that not initializing ->list field of
the returning damos_filter struct, which results in access to
uninitialized memory. Add a unit test for the function.
Link: https://lkml.kernel.org/r/20230729203733.38949-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When free_pages is 0, alike_pages is not used. So alike_pages calculation
can be avoided by checking free_pages early to save cpu cycles. Also fix
typo 'comparable'. It should be 'compatible' here.
Link: https://lkml.kernel.org/r/20230801123723.2225543-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
As ptep_get, Use the pmdp_get wrapper when we accessing pmdval instead of
directly dereferencing pmd.
Link: https://lkml.kernel.org/r/20230727212157.2985025-1-ppbuk5246@gmail.com
Signed-off-by: Levi Yun <ppbuk5246@gmail.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
