Commit graph

1827 commits

Author SHA1 Message Date
Linus Torvalds
bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook
69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Linus Torvalds
eeccf287a2 mm.git review status for linus..mm-stable
Total patches:       36
 Reviews/patch:       1.77
 Reviewed rate:       83%
 
 - The 2 patch series "mm/vmscan: fix demotion targets checks in
   reclaim/demotion" from Bing Jiao fixes a couple of issues in the
   demotion code - pages were failed demotion and were finding themselves
   demoted into disallowed nodes.
 
 - The 11 patch series "Remove XA_ZERO from error recovery of dup_mmap()"
   from Liam Howlett fixes a rare mapledtree race and performs a number of
   cleanups.
 
 - The 13 patch series "mm: add bitmap VMA flag helpers and convert all
   mmap_prepare to use them" from Lorenzo Stoakes implements a lot of
   cleanups following on from the conversion of the VMA flags into a
   bitmap.
 
 - The 5 patch series "support batch checking of references and unmapping
   for large folios" from Baolin Wang implements batching to greatly
   improve the performance of reclaiming clean file-backed large folios.
 
 - The 3 patch series "selftests/mm: add memory failure selftests" from
   Miaohe Lin does as claimed.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaZaIEQAKCRDdBJ7gKXxA
 jj73AQCQDwLoipDiQRGyjB5BDYydymWuDoiB1tlDPHfYAP3b/QD/UQtVlOEXqwM3
 naOKs3NQ1pwnfhDaQMirGw2eAnJ1SQY=
 =6Iif
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2026-02-18-19-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull more MM  updates from Andrew Morton:

 - "mm/vmscan: fix demotion targets checks in reclaim/demotion" fixes a
   couple of issues in the demotion code - pages were failed demotion
   and were finding themselves demoted into disallowed nodes (Bing Jiao)

 - "Remove XA_ZERO from error recovery of dup_mmap()" fixes a rare
   mapledtree race and performs a number of cleanups (Liam Howlett)

 - "mm: add bitmap VMA flag helpers and convert all mmap_prepare to use
   them" implements a lot of cleanups following on from the conversion
   of the VMA flags into a bitmap (Lorenzo Stoakes)

 - "support batch checking of references and unmapping for large folios"
   implements batching to greatly improve the performance of reclaiming
   clean file-backed large folios (Baolin Wang)

 - "selftests/mm: add memory failure selftests" does as claimed (Miaohe
   Lin)

* tag 'mm-stable-2026-02-18-19-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (36 commits)
  mm/page_alloc: clear page->private in free_pages_prepare()
  selftests/mm: add memory failure dirty pagecache test
  selftests/mm: add memory failure clean pagecache test
  selftests/mm: add memory failure anonymous page test
  mm: rmap: support batched unmapping for file large folios
  arm64: mm: implement the architecture-specific clear_flush_young_ptes()
  arm64: mm: support batch clearing of the young flag for large folios
  arm64: mm: factor out the address and ptep alignment into a new helper
  mm: rmap: support batched checks of the references for large folios
  tools/testing/vma: add VMA userland tests for VMA flag functions
  tools/testing/vma: separate out vma_internal.h into logical headers
  tools/testing/vma: separate VMA userland tests into separate files
  mm: make vm_area_desc utilise vma_flags_t only
  mm: update all remaining mmap_prepare users to use vma_flags_t
  mm: update shmem_[kernel]_file_*() functions to use vma_flags_t
  mm: update secretmem to use VMA flags on mmap_prepare
  mm: update hugetlbfs to use VMA flags on mmap_prepare
  mm: add basic VMA flag operation helper functions
  tools: bitmap: add missing bitmap_[subset(), andnot()]
  mm: add mk_vma_flags() bitmap flag macro helper
  ...
2026-02-18 20:50:32 -08:00
Bing Jiao
1aceed565f mm/vmscan: fix demotion targets checks in reclaim/demotion
Patch series "mm/vmscan: fix demotion targets checks in reclaim/demotion",
v9.

This patch series addresses two issues in demote_folio_list(),
can_demote(), and next_demotion_node() in reclaim/demotion.

1. demote_folio_list() and can_demote() do not correctly check
   demotion target against cpuset.mems_effective, which will cause (a)
   pages to be demoted to not-allowed nodes and (b) pages fail demotion
   even if the system still has allowed demotion nodes.

   Patch 1 fixes this bug by updating cpuset_node_allowed() and
   mem_cgroup_node_allowed() to return effective_mems, allowing directly
   logic-and operation against demotion targets.

2. next_demotion_node() returns a preferred demotion target, but it
   does not check the node against allowed nodes.

   Patch 2 ensures that next_demotion_node() filters against the allowed
   node mask and selects the closest demotion target to the source node.


This patch (of 2):

Fix two bugs in demote_folio_list() and can_demote() due to incorrect
demotion target checks against cpuset.mems_effective in reclaim/demotion.

Commit 7d709f49ba ("vmscan,cgroup: apply mems_effective to reclaim")
introduces the cpuset.mems_effective check and applies it to can_demote().
However:

  1. It does not apply this check in demote_folio_list(), which leads
     to situations where pages are demoted to nodes that are
     explicitly excluded from the task's cpuset.mems.

  2. It checks only the nodes in the immediate next demotion hierarchy
     and does not check all allowed demotion targets in can_demote().
     This can cause pages to never be demoted if the nodes in the next
     demotion hierarchy are not set in mems_effective.

These bugs break resource isolation provided by cpuset.mems.  This is
visible from userspace because pages can either fail to be demoted
entirely or are demoted to nodes that are not allowed in multi-tier memory
systems.

To address these bugs, update cpuset_node_allowed() and
mem_cgroup_node_allowed() to return effective_mems, allowing directly
logic-and operation against demotion targets.  Also update can_demote()
and demote_folio_list() accordingly.

Bug 1 reproduction:
  Assume a system with 4 nodes, where nodes 0-1 are top-tier and
  nodes 2-3 are far-tier memory. All nodes have equal capacity.

  Test script:
    echo 1 > /sys/kernel/mm/numa/demotion_enabled
    mkdir /sys/fs/cgroup/test
    echo +cpuset > /sys/fs/cgroup/cgroup.subtree_control
    echo "0-2" > /sys/fs/cgroup/test/cpuset.mems
    echo $$ > /sys/fs/cgroup/test/cgroup.procs
    swapoff -a
    # Expectation: Should respect node 0-2 limit.
    # Observation: Node 3 shows significant allocation (MemFree drops)
    stress-ng --oomable --vm 1 --vm-bytes 150% --mbind 0,1

Bug 2 reproduction:
  Assume a system with 6 nodes, where nodes 0-2 are top-tier,
  node 3 is a far-tier node, and nodes 4-5 are the farthest-tier nodes.
  All nodes have equal capacity.

  Test script:
    echo 1 > /sys/kernel/mm/numa/demotion_enabled
    mkdir /sys/fs/cgroup/test
    echo +cpuset > /sys/fs/cgroup/cgroup.subtree_control
    echo "0-2,4-5" > /sys/fs/cgroup/test/cpuset.mems
    echo $$ > /sys/fs/cgroup/test/cgroup.procs
    swapoff -a
    # Expectation: Pages are demoted to Nodes 4-5
    # Observation: No pages are demoted before oom.
    stress-ng --oomable --vm 1 --vm-bytes 150% --mbind 0,1,2

Link: https://lkml.kernel.org/r/20260114205305.2869796-1-bingjiao@google.com
Link: https://lkml.kernel.org/r/20260114205305.2869796-2-bingjiao@google.com
Fixes: 7d709f49ba ("vmscan,cgroup: apply mems_effective to reclaim")
Signed-off-by: Bing Jiao <bingjiao@google.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Gregory Price <gourry@gourry.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Waiman Long <longman@redhat.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-02-12 15:42:52 -08:00
Linus Torvalds
4cff5c05e0 mm.git review status for linus..mm-stable
Everything:
 
 Total patches:       325
 Reviews/patch:       1.39
 Reviewed rate:       72%
 
 Excluding DAMON:
 
 Total patches:       262
 Reviews/patch:       1.63
 Reviewed rate:       82%
 
 Excluding DAMON and zram:
 
 Total patches:       248
 Reviews/patch:       1.72
 Reviewed rate:       86%
 
 - The 14 patch series "powerpc/64s: do not re-activate batched TLB
   flush" from Alexander Gordeev makes arch_{enter|leave}_lazy_mmu_mode()
   nest properly.
 
   It adds a generic enter/leave layer and switches architectures to use
   it.  Various hacks were removed in the process.
 
 - The 7 patch series "zram: introduce compressed data writeback" from
   Richard Chang and Sergey Senozhatsky implements data compression for
   zram writeback.
 
 - The 8 patch series "mm: folio_zero_user: clear page ranges" from David
   Hildenbrand adds clearing of contiguous page ranges for hugepages.
   Large improvements during demand faulting are demonstrated.
 
 - The 2 patch series "memcg cleanups" from Chen Ridong tideis up some
   memcg code.
 
 - The 12 patch series "mm/damon: introduce {,max_}nr_snapshots and
   tracepoint for damos stats" from SeongJae Park improves DAMOS stat's
   provided information, deterministic control, and readability.
 
 - The 3 patch series "selftests/mm: hugetlb cgroup charging: robustness
   fixes" from Li Wang fixes a few issues in the hugetlb cgroup charging
   selftests.
 
 - The 5 patch series "Fix va_high_addr_switch.sh test failure - again"
   from Chunyu Hu addresses several issues in the va_high_addr_switch test.
 
 - The 5 patch series "mm/damon/tests/core-kunit: extend existing test
   scenarios" from Shu Anzai improves the KUnit test coverage for DAMON.
 
 - The 2 patch series "mm/khugepaged: fix dirty page handling for
   MADV_COLLAPSE" from Shivank Garg fixes a glitch in khugepaged which was
   causing madvise(MADV_COLLAPSE) to transiently return -EAGAIN.
 
 - The 29 patch series "arch, mm: consolidate hugetlb early reservation"
   from Mike Rapoport reworks and consolidates a pile of straggly code
   related to reservation of hugetlb memory from bootmem and creation of
   CMA areas for hugetlb.
 
 - The 9 patch series "mm: clean up anon_vma implementation" from Lorenzo
   Stoakes cleans up the anon_vma implementation in various ways.
 
 - The 3 patch series "tweaks for __alloc_pages_slowpath()" from
   Vlastimil Babka does a little streamlining of the page allocator's
   slowpath code.
 
 - The 8 patch series "memcg: separate private and public ID namespaces"
   from Shakeel Butt cleans up the memcg ID code and prevents the
   internal-only private IDs from being exposed to userspace.
 
 - The 6 patch series "mm: hugetlb: allocate frozen gigantic folio" from
   Kefeng Wang cleans up the allocation of frozen folios and avoids some
   atomic refcount operations.
 
 - The 11 patch series "mm/damon: advance DAMOS-based LRU sorting" from
   SeongJae Park improves DAMOS's movement of memory betewwn the active and
   inactive LRUs and adds auto-tuning of the ratio-based quotas and of
   monitoring intervals.
 
 - The 18 patch series "Support page table check on PowerPC" from Andrew
   Donnellan makes CONFIG_PAGE_TABLE_CHECK_ENFORCED work on powerpc.
 
 - The 3 patch series "nodemask: align nodes_and{,not} with underlying
   bitmap ops" from Yury Norov makes nodes_and() and nodes_andnot()
   propagate the return values from the underlying bit operations, enabling
   some cleanup in calling code.
 
 - The 5 patch series "mm/damon: hide kdamond and kdamond_lock from API
   callers" from SeongJae Park cleans up some DAMON internal interfaces.
 
 - The 4 patch series "mm/khugepaged: cleanups and scan limit fix" from
   Shivank Garg does some cleanup work in khupaged and fixes a scan limit
   accounting issue.
 
 - The 24 patch series "mm: balloon infrastructure cleanups" from David
   Hildenbrand goes to town on the balloon infrastructure and its page
   migration function.  Mainly cleanups, also some locking simplification.
 
 - The 2 patch series "mm/vmscan: add tracepoint and reason for
   kswapd_failures reset" from Jiayuan Chen adds additional tracepoints to
   the page reclaim code.
 
 - The 3 patch series "Replace wq users and add WQ_PERCPU to
   alloc_workqueue() users" from Marco Crivellari is part of Marco's
   kernel-wide migration from the legacy workqueue APIs over to the
   preferred unbound workqueues.
 
 - The 9 patch series "Various mm kselftests improvements/fixes" from
   Kevin Brodsky provides various unrelated improvements/fixes for the mm
   kselftests.
 
 - The 5 patch series "mm: accelerate gigantic folio allocation" from
   Kefeng Wang greatly speeds up gigantic folio allocation, mainly by
   avoiding unnecessary work in pfn_range_valid_contig().
 
 - The 5 patch series "selftests/damon: improve leak detection and wss
   estimation reliability" from SeongJae Park improves the reliability of
   two of the DAMON selftests.
 
 - The 8 patch series "mm/damon: cleanup kdamond, damon_call(), damos
   filter and DAMON_MIN_REGION" from SeongJae Park does some cleanup work
   in the core DAMON code.
 
 - The 8 patch series "Docs/mm/damon: update intro, modules, maintainer
   profile, and misc" from SeongJae Park performs maintenance work on the
   DAMON documentation.
 
 - The 10 patch series "mm: add and use vma_assert_stabilised() helper"
   from Lorenzo Stoakes refactors and cleans up the core VMA code.  The
   main aim here is to be able to use the mmap write lock's lockdep state
   to perform various assertions regarding the locking which the VMA code
   requires.
 
 - The 19 patch series "mm, swap: swap table phase II: unify swapin use"
   from Kairui Song removes some old swap code (swap cache bypassing and
   swap synchronization) which wasn't working very well.  Various other
   cleanups and simplifications were made.  The end result is a 20% speedup
   in one benchmark.
 
 - The 8 patch series "enable PT_RECLAIM on more 64-bit architectures"
   from Qi Zheng makes PT_RECLAIM available on 64-bit alpha, loongarch,
   mips, parisc, um,  Various cleanups were performed along the way.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaY1HfAAKCRDdBJ7gKXxA
 jqhZAP9H8ZlKKqCEgnr6U5XXmJ63Ep2FDQpl8p35yr9yVuU9+gEAgfyWiJ43l1fP
 rT0yjsUW3KQFBi/SEA3R6aYarmoIBgI=
 =+HLt
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - "powerpc/64s: do not re-activate batched TLB flush" makes
   arch_{enter|leave}_lazy_mmu_mode() nest properly (Alexander Gordeev)

   It adds a generic enter/leave layer and switches architectures to use
   it. Various hacks were removed in the process.

 - "zram: introduce compressed data writeback" implements data
   compression for zram writeback (Richard Chang and Sergey Senozhatsky)

 - "mm: folio_zero_user: clear page ranges" adds clearing of contiguous
   page ranges for hugepages. Large improvements during demand faulting
   are demonstrated (David Hildenbrand)

 - "memcg cleanups" tidies up some memcg code (Chen Ridong)

 - "mm/damon: introduce {,max_}nr_snapshots and tracepoint for damos
   stats" improves DAMOS stat's provided information, deterministic
   control, and readability (SeongJae Park)

 - "selftests/mm: hugetlb cgroup charging: robustness fixes" fixes a few
   issues in the hugetlb cgroup charging selftests (Li Wang)

 - "Fix va_high_addr_switch.sh test failure - again" addresses several
   issues in the va_high_addr_switch test (Chunyu Hu)

 - "mm/damon/tests/core-kunit: extend existing test scenarios" improves
   the KUnit test coverage for DAMON (Shu Anzai)

 - "mm/khugepaged: fix dirty page handling for MADV_COLLAPSE" fixes a
   glitch in khugepaged which was causing madvise(MADV_COLLAPSE) to
   transiently return -EAGAIN (Shivank Garg)

 - "arch, mm: consolidate hugetlb early reservation" reworks and
   consolidates a pile of straggly code related to reservation of
   hugetlb memory from bootmem and creation of CMA areas for hugetlb
   (Mike Rapoport)

 - "mm: clean up anon_vma implementation" cleans up the anon_vma
   implementation in various ways (Lorenzo Stoakes)

 - "tweaks for __alloc_pages_slowpath()" does a little streamlining of
   the page allocator's slowpath code (Vlastimil Babka)

 - "memcg: separate private and public ID namespaces" cleans up the
   memcg ID code and prevents the internal-only private IDs from being
   exposed to userspace (Shakeel Butt)

 - "mm: hugetlb: allocate frozen gigantic folio" cleans up the
   allocation of frozen folios and avoids some atomic refcount
   operations (Kefeng Wang)

 - "mm/damon: advance DAMOS-based LRU sorting" improves DAMOS's movement
   of memory betewwn the active and inactive LRUs and adds auto-tuning
   of the ratio-based quotas and of monitoring intervals (SeongJae Park)

 - "Support page table check on PowerPC" makes
   CONFIG_PAGE_TABLE_CHECK_ENFORCED work on powerpc (Andrew Donnellan)

 - "nodemask: align nodes_and{,not} with underlying bitmap ops" makes
   nodes_and() and nodes_andnot() propagate the return values from the
   underlying bit operations, enabling some cleanup in calling code
   (Yury Norov)

 - "mm/damon: hide kdamond and kdamond_lock from API callers" cleans up
   some DAMON internal interfaces (SeongJae Park)

 - "mm/khugepaged: cleanups and scan limit fix" does some cleanup work
   in khupaged and fixes a scan limit accounting issue (Shivank Garg)

 - "mm: balloon infrastructure cleanups" goes to town on the balloon
   infrastructure and its page migration function. Mainly cleanups, also
   some locking simplification (David Hildenbrand)

 - "mm/vmscan: add tracepoint and reason for kswapd_failures reset" adds
   additional tracepoints to the page reclaim code (Jiayuan Chen)

 - "Replace wq users and add WQ_PERCPU to alloc_workqueue() users" is
   part of Marco's kernel-wide migration from the legacy workqueue APIs
   over to the preferred unbound workqueues (Marco Crivellari)

 - "Various mm kselftests improvements/fixes" provides various unrelated
   improvements/fixes for the mm kselftests (Kevin Brodsky)

 - "mm: accelerate gigantic folio allocation" greatly speeds up gigantic
   folio allocation, mainly by avoiding unnecessary work in
   pfn_range_valid_contig() (Kefeng Wang)

 - "selftests/damon: improve leak detection and wss estimation
   reliability" improves the reliability of two of the DAMON selftests
   (SeongJae Park)

 - "mm/damon: cleanup kdamond, damon_call(), damos filter and
   DAMON_MIN_REGION" does some cleanup work in the core DAMON code
   (SeongJae Park)

 - "Docs/mm/damon: update intro, modules, maintainer profile, and misc"
   performs maintenance work on the DAMON documentation (SeongJae Park)

 - "mm: add and use vma_assert_stabilised() helper" refactors and cleans
   up the core VMA code. The main aim here is to be able to use the mmap
   write lock's lockdep state to perform various assertions regarding
   the locking which the VMA code requires (Lorenzo Stoakes)

 - "mm, swap: swap table phase II: unify swapin use" removes some old
   swap code (swap cache bypassing and swap synchronization) which
   wasn't working very well. Various other cleanups and simplifications
   were made. The end result is a 20% speedup in one benchmark (Kairui
   Song)

 - "enable PT_RECLAIM on more 64-bit architectures" makes PT_RECLAIM
   available on 64-bit alpha, loongarch, mips, parisc, and um. Various
   cleanups were performed along the way (Qi Zheng)

* tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (325 commits)
  mm/memory: handle non-split locks correctly in zap_empty_pte_table()
  mm: move pte table reclaim code to memory.c
  mm: make PT_RECLAIM depends on MMU_GATHER_RCU_TABLE_FREE
  mm: convert __HAVE_ARCH_TLB_REMOVE_TABLE to CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE config
  um: mm: enable MMU_GATHER_RCU_TABLE_FREE
  parisc: mm: enable MMU_GATHER_RCU_TABLE_FREE
  mips: mm: enable MMU_GATHER_RCU_TABLE_FREE
  LoongArch: mm: enable MMU_GATHER_RCU_TABLE_FREE
  alpha: mm: enable MMU_GATHER_RCU_TABLE_FREE
  mm: change mm/pt_reclaim.c to use asm/tlb.h instead of asm-generic/tlb.h
  mm/damon/stat: remove __read_mostly from memory_idle_ms_percentiles
  zsmalloc: make common caches global
  mm: add SPDX id lines to some mm source files
  mm/zswap: use %pe to print error pointers
  mm/vmscan: use %pe to print error pointers
  mm/readahead: fix typo in comment
  mm: khugepaged: fix NR_FILE_PAGES and NR_SHMEM in collapse_file()
  mm: refactor vma_map_pages to use vm_insert_pages
  mm/damon: unify address range representation with damon_addr_range
  mm/cma: replace snprintf with strscpy in cma_new_area
  ...
2026-02-12 11:32:37 -08:00
Linus Torvalds
148f95f75c slab updates for 7.0
-----BEGIN PGP SIGNATURE-----
 
 iQFPBAABCAA5FiEEe7vIQRWZI0iWSE3xu+CwddJFiJoFAmmK68UbFIAAAAAABAAO
 bWFudTIsMi41KzEuMTEsMiwyAAoJELvgsHXSRYiamM8H/0eOKSvZG/C/HdTm36cy
 pVjOjgX9KmlHoeH1dOMjqgL2KfOIBis8j1GY0Q/qF1a86uzQa6uuz4XdmJeTUkEE
 YfzwOdaLIR0U6R/gIH9YPfyU9h3VBLUNtotDculntSO3ZgwY5QUHQHz+ROnVG5SU
 MSQ2oshSRkh06LRIlvbd0kLax8vZy8UjfYPonF33+XRya17nIY6V2DvqC0MDuEcM
 jWvbQfm5HTamTAlSV4bmJw+U/FehEdpC4U0ulsAtQILGpJvHCwqDGCNQRFkzcsaM
 yhi1JLFCZcoHqbQycZMNAypPERfIp8O5thSU6xU2AP/cNl2scR/7/MSuWOvjKBv4
 pKU=
 =u52A
 -----END PGP SIGNATURE-----

Merge tag 'slab-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

Pull slab updates from Vlastimil Babka:

 - The percpu sheaves caching layer was introduced as opt-in in 6.18 and
   now we enable it for all caches and remove the previous cpu (partial)
   slab caching mechanism.

   Besides the lower locking overhead and much more likely fastpath when
   freeing, this removes the rather complicated code related to the cpu
   slab lockless fastpaths (using this_cpu_try_cmpxchg128/64) and all
   its complications for PREEMPT_RT or kmalloc_nolock().

   The lockless slab freelist+counters update operation using
   try_cmpxchg128/64 remains and is crucial for freeing remote NUMA
   objects, and to allow flushing objects from sheaves to slabs mostly
   without the node list_lock (Vlastimil Babka)

 - Eliminate slabobj_ext metadata overhead when possible. Instead of
   using kmalloc() to allocate the array for memcg and/or allocation
   profiling tag pointers, use leftover space in a slab or per-object
   padding due to alignment (Harry Yoo)

 - Various followup improvements to the above (Hao Li)

* tag 'slab-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: (39 commits)
  slub: let need_slab_obj_exts() return false if SLAB_NO_OBJ_EXT is set
  mm/slab: only allow SLAB_OBJ_EXT_IN_OBJ for unmergeable caches
  mm/slab: place slabobj_ext metadata in unused space within s->size
  mm/slab: move [__]ksize and slab_ksize() to mm/slub.c
  mm/slab: save memory by allocating slabobj_ext array from leftover
  mm/memcontrol,alloc_tag: handle slabobj_ext access under KASAN poison
  mm/slab: use stride to access slabobj_ext
  mm/slab: abstract slabobj_ext access via new slab_obj_ext() helper
  ext4: specify the free pointer offset for ext4_inode_cache
  mm/slab: allow specifying free pointer offset when using constructor
  mm/slab: use unsigned long for orig_size to ensure proper metadata align
  slub: clarify object field layout comments
  mm/slab: avoid allocating slabobj_ext array from its own slab
  slub: avoid list_lock contention from __refill_objects_any()
  mm/slub: cleanup and repurpose some stat items
  mm/slub: remove DEACTIVATE_TO_* stat items
  slab: remove frozen slab checks from __slab_free()
  slab: update overview comments
  slab: refill sheaves from all nodes
  slab: remove unused PREEMPT_RT specific macros
  ...
2026-02-11 14:12:50 -08:00
Linus Torvalds
ff661eeee2 cgroup: Changes for v6.20
- cpuset changes:
 
   - Continue separating v1 and v2 implementations by moving more
     v1-specific logic into cpuset-v1.c.
 
   - Improve partition handling. Sibling partitions are no longer
     invalidated on cpuset.cpus conflict, cpuset.cpus changes no longer
     fail in v2, and effective_xcpus computation is made consistent.
 
   - Fix partition effective CPUs overlap that caused a warning on cpuset
     removal when sibling partitions shared CPUs.
 
 - Increase the maximum cgroup subsystem count from 16 to 32 to
   accommodate future subsystem additions.
 
 - Misc cleanups and selftest improvements including switching to
   css_is_online() helper, removing dead code and stale documentation
   references, using lockdep_assert_cpuset_lock_held() consistently,
   and adding polling helpers for asynchronously updated cgroup
   statistics.
 -----BEGIN PGP SIGNATURE-----
 
 iIQEABYKACwWIQTfIjM1kS57o3GsC/uxYfJx3gVYGQUCaYozIw4cdGpAa2VybmVs
 Lm9yZwAKCRCxYfJx3gVYGZQKAQD51KJQz4M79wf2yBhIBLOnM4aakMalhSwZNL4O
 JiGutwD+Ir33VzNX8aXBuDin9p4wI15O54PhqSenJbelKRQ3Dws=
 =gR7L
 -----END PGP SIGNATURE-----

Merge tag 'cgroup-for-6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:

 - cpuset changes:

    - Continue separating v1 and v2 implementations by moving more
      v1-specific logic into cpuset-v1.c

    - Improve partition handling. Sibling partitions are no longer
      invalidated on cpuset.cpus conflict, cpuset.cpus changes no longer
      fail in v2, and effective_xcpus computation is made consistent

    - Fix partition effective CPUs overlap that caused a warning on
      cpuset removal when sibling partitions shared CPUs

 - Increase the maximum cgroup subsystem count from 16 to 32 to
   accommodate future subsystem additions

 - Misc cleanups and selftest improvements including switching to
   css_is_online() helper, removing dead code and stale documentation
   references, using lockdep_assert_cpuset_lock_held() consistently, and
   adding polling helpers for asynchronously updated cgroup statistics

* tag 'cgroup-for-6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (21 commits)
  cpuset: fix overlap of partition effective CPUs
  cgroup: increase maximum subsystem count from 16 to 32
  cgroup: Remove stale cpu.rt.max reference from documentation
  cpuset: replace direct lockdep_assert_held() with lockdep_assert_cpuset_lock_held()
  cgroup/cpuset: Move the v1 empty cpus/mems check to cpuset1_validate_change()
  cgroup/cpuset: Don't invalidate sibling partitions on cpuset.cpus conflict
  cgroup/cpuset: Don't fail cpuset.cpus change in v2
  cgroup/cpuset: Consistently compute effective_xcpus in update_cpumasks_hier()
  cgroup/cpuset: Streamline rm_siblings_excl_cpus()
  cpuset: remove dead code in cpuset-v1.c
  cpuset: remove v1-specific code from generate_sched_domains
  cpuset: separate generate_sched_domains for v1 and v2
  cpuset: move update_domain_attr_tree to cpuset_v1.c
  cpuset: add cpuset1_init helper for v1 initialization
  cpuset: add cpuset1_online_css helper for v1-specific operations
  cpuset: add lockdep_assert_cpuset_lock_held helper
  cpuset: Remove unnecessary checks in rebuild_sched_domains_locked
  cgroup: switch to css_is_online() helper
  selftests: cgroup: Replace sleep with cg_read_key_long_poll() for waiting on nr_dying_descendants
  selftests: cgroup: make test_memcg_sock robust against delayed sock stats
  ...
2026-02-11 13:20:50 -08:00
Linus Torvalds
f17b474e36 bpf-next-7.0
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE+soXsSLHKoYyzcli6rmadz2vbToFAmmGmrgACgkQ6rmadz2v
 bTq6NxAAkCHosxzGn9GYYBV8xhrBJoJJDCyEbQ4nR0XNY+zaWnuykmiPP9w1aOAM
 zm/po3mQB2pZjetvlrPrgG5RLgBCAUHzqVGy0r+phUvD3vbohKlmSlMm2kiXOb9N
 T01BgLWsyqN2ZcNFvORdSsftqIJUHcXxU6RdupGD60sO5XM9ty5cwyewLX8GBOas
 UN2bOhbK2DpqYWUvtv+3Q3ykxoStMSkXZvDRurwLKl4RHeLjXZXPo8NjnfBlk/F2
 vdFo/F4NO4TmhOave6UPXvKb4yo9IlBRmiPAl0RmNKBxenY8j9XuV/xZxU6YgzDn
 +SQfDK+CKQ4IYIygE+fqd4e5CaQrnjmPPcIw12AB2CF0LimY9Xxyyk6FSAhMN7wm
 GTVh5K2C3Dk3OiRQk4G58EvQ5QcxzX98IeeCpcckMUkPsFWHRvF402WMUcv9SWpD
 DsxxPkfENY/6N67EvH0qcSe/ikdUorQKFl4QjXKwsMCd5WhToeP4Z7Ck1gVSNkAh
 9CX++mLzg333Lpsc4SSIuk9bEPpFa5cUIKUY7GCsCiuOXciPeMDP3cGSd5LioqxN
 qWljs4Z88QDM2LJpAh8g4m3sA7bMhES3nPmdlI5CfgBcVyLW8D8CqQq4GEZ1McwL
 Ky084+lEosugoVjRejrdMMEOsqAfcbkTr2b8jpuAZdwJKm6p/bw=
 =cBdK
 -----END PGP SIGNATURE-----

Merge tag 'bpf-next-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Pull bpf updates from Alexei Starovoitov:

 - Support associating BPF program with struct_ops (Amery Hung)

 - Switch BPF local storage to rqspinlock and remove recursion detection
   counters which were causing false positives (Amery Hung)

 - Fix live registers marking for indirect jumps (Anton Protopopov)

 - Introduce execution context detection BPF helpers (Changwoo Min)

 - Improve verifier precision for 32bit sign extension pattern
   (Cupertino Miranda)

 - Optimize BTF type lookup by sorting vmlinux BTF and doing binary
   search (Donglin Peng)

 - Allow states pruning for misc/invalid slots in iterator loops (Eduard
   Zingerman)

 - In preparation for ASAN support in BPF arenas teach libbpf to move
   global BPF variables to the end of the region and enable arena kfuncs
   while holding locks (Emil Tsalapatis)

 - Introduce support for implicit arguments in kfuncs and migrate a
   number of them to new API. This is a prerequisite for cgroup
   sub-schedulers in sched-ext (Ihor Solodrai)

 - Fix incorrect copied_seq calculation in sockmap (Jiayuan Chen)

 - Fix ORC stack unwind from kprobe_multi (Jiri Olsa)

 - Speed up fentry attach by using single ftrace direct ops in BPF
   trampolines (Jiri Olsa)

 - Require frozen map for calculating map hash (KP Singh)

 - Fix lock entry creation in TAS fallback in rqspinlock (Kumar
   Kartikeya Dwivedi)

 - Allow user space to select cpu in lookup/update operations on per-cpu
   array and hash maps (Leon Hwang)

 - Make kfuncs return trusted pointers by default (Matt Bobrowski)

 - Introduce "fsession" support where single BPF program is executed
   upon entry and exit from traced kernel function (Menglong Dong)

 - Allow bpf_timer and bpf_wq use in all programs types (Mykyta
   Yatsenko, Andrii Nakryiko, Kumar Kartikeya Dwivedi, Alexei
   Starovoitov)

 - Make KF_TRUSTED_ARGS the default for all kfuncs and clean up their
   definition across the tree (Puranjay Mohan)

 - Allow BPF arena calls from non-sleepable context (Puranjay Mohan)

 - Improve register id comparison logic in the verifier and extend
   linked registers with negative offsets (Puranjay Mohan)

 - In preparation for BPF-OOM introduce kfuncs to access memcg events
   (Roman Gushchin)

 - Use CFI compatible destructor kfunc type (Sami Tolvanen)

 - Add bitwise tracking for BPF_END in the verifier (Tianci Cao)

 - Add range tracking for BPF_DIV and BPF_MOD in the verifier (Yazhou
   Tang)

 - Make BPF selftests work with 64k page size (Yonghong Song)

* tag 'bpf-next-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (268 commits)
  selftests/bpf: Fix outdated test on storage->smap
  selftests/bpf: Choose another percpu variable in bpf for btf_dump test
  selftests/bpf: Remove test_task_storage_map_stress_lookup
  selftests/bpf: Update task_local_storage/task_storage_nodeadlock test
  selftests/bpf: Update task_local_storage/recursion test
  selftests/bpf: Update sk_storage_omem_uncharge test
  bpf: Switch to bpf_selem_unlink_nofail in bpf_local_storage_{map_free, destroy}
  bpf: Support lockless unlink when freeing map or local storage
  bpf: Prepare for bpf_selem_unlink_nofail()
  bpf: Remove unused percpu counter from bpf_local_storage_map_free
  bpf: Remove cgroup local storage percpu counter
  bpf: Remove task local storage percpu counter
  bpf: Change local_storage->lock and b->lock to rqspinlock
  bpf: Convert bpf_selem_unlink to failable
  bpf: Convert bpf_selem_link_map to failable
  bpf: Convert bpf_selem_unlink_map to failable
  bpf: Select bpf_local_storage_map_bucket based on bpf_local_storage
  selftests/xsk: fix number of Tx frags in invalid packet
  selftests/xsk: properly handle batch ending in the middle of a packet
  bpf: Prevent reentrance into call_rcu_tasks_trace()
  ...
2026-02-10 11:26:21 -08:00
Linus Torvalds
d16738a4e7 The kthread code provides an infrastructure which manages the preferred
affinity of unbound kthreads (node or custom cpumask) against
 housekeeping (CPU isolation) constraints and CPU hotplug events.
 
 One crucial missing piece is the handling of cpuset: when an isolated
 partition is created, deleted, or its CPUs updated, all the unbound
 kthreads in the top cpuset become indifferently affine to _all_ the
 non-isolated CPUs, possibly breaking their preferred affinity along
 the way.
 
 Solve this with performing the kthreads affinity update from cpuset to
 the kthreads consolidated relevant code instead so that preferred
 affinities are honoured and applied against the updated cpuset isolated
 partitions.
 
 The dispatch of the new isolated cpumasks to timers, workqueues and
 kthreads is performed by housekeeping, as per the nice Tejun's
 suggestion.
 
 As a welcome side effect, HK_TYPE_DOMAIN then integrates both the set
 from boot defined domain isolation (through isolcpus=) and cpuset
 isolated partitions. Housekeeping cpumasks are now modifiable with a
 specific RCU based synchronization. A big step toward making nohz_full=
 also mutable through cpuset in the future.
 -----BEGIN PGP SIGNATURE-----
 
 iQJPBAABCAA5FiEEd76+gtGM8MbftQlOhSRUR1COjHcFAmmE0mYbFIAAAAAABAAO
 bWFudTIsMi41KzEuMTEsMiwyAAoJEIUkVEdQjox36eMP/0Ls/ArfYVi/MNAXWlpy
 rAt6m9Y/X9GBcDM/VI9BXq1ZX4qEr2XjJ8UUb8cM08uHEAt0ErlmpRxREwJFrKbI
 H4jzg5EwO0D0c6MnvgQJEAwkHxQVIjsxG9DovRIjxyW4ycx3aSsRg/f2VKyWoLvY
 7ZT7CbLFE+I/MQh2ZgUu/9pnCDQVR2anss2WYIej5mmgFL5pyEv3YvYgKYVyK08z
 sXyNxpP976g2d9ECJ9OtFJV9we6mlqxlG0MVCiv/Uxh7DBjxWWPsLvlmLAXggQ03
 +0GW+nnutDaKz83pgS7Z4zum/+Oa+I1dTLIN27pARUNcMCYip7njM2KNpJwPdov3
 +fAIODH2JVX1xewT+U1cCq6gdI55ejbwdQYGFV075dKBUxKQeIyrghvfC3Ga6aKQ
 Gw3y68jdrXOw6iyfHR5k/0Mnu2/FDKUW2fZxLKm55PvNZP5jQFmSlz9wyiwwyb3m
 UUSgThj6Ozodxks8hDX41rGVezCcm1ni+qNSiNIs8HPaaZQrwbnvKHQFBBJHQzJP
 rJ39VWBx3Hq/ly71BOR6pCzoZsfS1f85YKhJ4vsfjLO6BfhI16nBat89eROSRKcz
 XptyWqW0PgAD0teDuMCTPNuUym/viBHALXHKuSO12CIizacvftiGcmaQNPlLiiFZ
 /Dr2+aOhwYw3UD6djn3u94M9
 =nWGh
 -----END PGP SIGNATURE-----

Merge tag 'kthread-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks

Pull kthread updates from Frederic Weisbecker:
 "The kthread code provides an infrastructure which manages the
  preferred affinity of unbound kthreads (node or custom cpumask)
  against housekeeping (CPU isolation) constraints and CPU hotplug
  events.

  One crucial missing piece is the handling of cpuset: when an isolated
  partition is created, deleted, or its CPUs updated, all the unbound
  kthreads in the top cpuset become indifferently affine to _all_ the
  non-isolated CPUs, possibly breaking their preferred affinity along
  the way.

  Solve this with performing the kthreads affinity update from cpuset to
  the kthreads consolidated relevant code instead so that preferred
  affinities are honoured and applied against the updated cpuset
  isolated partitions.

  The dispatch of the new isolated cpumasks to timers, workqueues and
  kthreads is performed by housekeeping, as per the nice Tejun's
  suggestion.

  As a welcome side effect, HK_TYPE_DOMAIN then integrates both the set
  from boot defined domain isolation (through isolcpus=) and cpuset
  isolated partitions. Housekeeping cpumasks are now modifiable with a
  specific RCU based synchronization. A big step toward making
  nohz_full= also mutable through cpuset in the future"

* tag 'kthread-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks: (33 commits)
  doc: Add housekeeping documentation
  kthread: Document kthread_affine_preferred()
  kthread: Comment on the purpose and placement of kthread_affine_node() call
  kthread: Honour kthreads preferred affinity after cpuset changes
  sched/arm64: Move fallback task cpumask to HK_TYPE_DOMAIN
  sched: Switch the fallback task allowed cpumask to HK_TYPE_DOMAIN
  kthread: Rely on HK_TYPE_DOMAIN for preferred affinity management
  kthread: Include kthreadd to the managed affinity list
  kthread: Include unbound kthreads in the managed affinity list
  kthread: Refine naming of affinity related fields
  PCI: Remove superfluous HK_TYPE_WQ check
  sched/isolation: Remove HK_TYPE_TICK test from cpu_is_isolated()
  cpuset: Remove cpuset_cpu_is_isolated()
  timers/migration: Remove superfluous cpuset isolation test
  cpuset: Propagate cpuset isolation update to timers through housekeeping
  cpuset: Propagate cpuset isolation update to workqueue through housekeeping
  PCI: Flush PCI probe workqueue on cpuset isolated partition change
  sched/isolation: Flush vmstat workqueues on cpuset isolated partition change
  sched/isolation: Flush memcg workqueues on cpuset isolated partition change
  cpuset: Update HK_TYPE_DOMAIN cpumask from cpuset
  ...
2026-02-09 19:57:30 -08:00
Harry Yoo
4b1530f89c mm/memcontrol,alloc_tag: handle slabobj_ext access under KASAN poison
In the near future, slabobj_ext may reside outside the allocated slab
object range within a slab, which could be reported as an out-of-bounds
access by KASAN.

As suggested by Andrey Konovalov [1], explicitly disable KASAN and KMSAN
checks when accessing slabobj_ext within slab allocator, memory profiling,
and memory cgroup code. While an alternative approach could be to unpoison
slabobj_ext, out-of-bounds accesses outside the slab allocator are
generally more common.

Move metadata_access_enable()/disable() helpers to mm/slab.h so that
it can be used outside mm/slub.c. However, as suggested by Suren
Baghdasaryan [2], instead of calling them directly from mm code (which is
more prone to errors), change users to access slabobj_ext via get/put
APIs:

  - Users should call get_slab_obj_exts() to access slabobj_metadata
    and call put_slab_obj_exts() when it's done.

  - From now on, accessing it outside the section covered by
    get_slab_obj_exts() ~ put_slab_obj_exts() is illegal.
    This ensures that accesses to slabobj_ext metadata won't be reported
    as access violations.

Call kasan_reset_tag() in slab_obj_ext() before returning the address to
prevent SW or HW tag-based KASAN from reporting false positives.

Suggested-by: Andrey Konovalov <andreyknvl@gmail.com>
Suggested-by: Suren Baghdasaryan <surenb@google.com>
Link: https://lore.kernel.org/linux-mm/CA+fCnZezoWn40BaS3cgmCeLwjT+5AndzcQLc=wH3BjMCu6_YCw@mail.gmail.com [1]
Link: https://lore.kernel.org/linux-mm/CAJuCfpG=Lb4WhYuPkSpdNO4Ehtjm1YcEEK0OM=3g9i=LxmpHSQ@mail.gmail.com [2]
Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Link: https://patch.msgid.link/20260113061845.159790-7-harry.yoo@oracle.com
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2026-02-04 10:05:35 +01:00
Harry Yoo
52f1ca8a45 mm/slab: abstract slabobj_ext access via new slab_obj_ext() helper
Currently, the slab allocator assumes that slab->obj_exts is a pointer
to an array of struct slabobj_ext objects. However, to support storage
methods where struct slabobj_ext is embedded within objects, the slab
allocator should not make this assumption. Instead of directly
dereferencing the slabobj_exts array, abstract access to
struct slabobj_ext via helper functions.

Introduce a new API slabobj_ext metadata access:

  slab_obj_ext(slab, obj_exts, index) - returns the pointer to
  struct slabobj_ext element at the given index.

Directly dereferencing the return value of slab_obj_exts() is no longer
allowed. Instead, slab_obj_ext() must always be used to access
individual struct slabobj_ext objects.

Convert all users to use these APIs.
No functional changes intended.

Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Link: https://patch.msgid.link/20260113061845.159790-5-harry.yoo@oracle.com
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2026-02-04 10:05:35 +01:00
Frederic Weisbecker
b7eb4edcc3 sched/isolation: Flush memcg workqueues on cpuset isolated partition change
The HK_TYPE_DOMAIN housekeeping cpumask is now modifiable at runtime. In
order to synchronize against memcg workqueue to make sure that no
asynchronous draining is still pending or executing on a newly made
isolated CPU, the housekeeping susbsystem must flush the memcg
workqueues.

However the memcg workqueues can't be flushed easily since they are
queued to the main per-CPU workqueue pool.

Solve this with creating a memcg specific pool and provide and use the
appropriate flushing API.

Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Marco Crivellari <marco.crivellari@suse.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Waiman Long <longman@redhat.com>
Cc: cgroups@vger.kernel.org
Cc: linux-mm@kvack.org
2026-02-03 15:23:34 +01:00
Frederic Weisbecker
2d05068610 memcg: Prepare to protect against concurrent isolated cpuset change
The HK_TYPE_DOMAIN housekeeping cpumask will soon be made modifiable at
runtime. In order to synchronize against memcg workqueue to make sure
that no asynchronous draining is pending or executing on a newly made
isolated CPU, target and queue a drain work under the same RCU critical
section.

Whenever housekeeping will update the HK_TYPE_DOMAIN cpumask, a memcg
workqueue flush will also be issued in a further change to make sure
that no work remains pending after a CPU has been made isolated.

Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Marco Crivellari <marco.crivellari@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Waiman Long <longman@redhat.com>
2026-02-03 15:19:38 +01:00
Marco Crivellari
0bcbd7cf65 mm: replace use of system_unbound_wq with system_dfl_wq
Patch series "Replace wq users and add WQ_PERCPU to alloc_workqueue()
users", v2.

This series continues the effort to refactor the Workqueue API.  No
behavior changes are introduced by this series.

=== Recent changes to the WQ API ===

The following, address the recent changes in the Workqueue API:

- commit 128ea9f6cc ("workqueue: Add system_percpu_wq and system_dfl_wq")
- commit 930c2ea566 ("workqueue: Add new WQ_PERCPU flag")

The old workqueues will be removed in a future release cycle and
unbound will become the implicit default.

=== Introduced Changes by this series ===

1) [P 1-2] Replace use of system_wq and system_unbound_wq

    Workqueue users converted to the better named new workqueues:

        system_wq -> system_percpu_wq
        system_unbound_wq -> system_dfl_wq

    This way the old obsolete workqueues (system_wq, system_unbound_wq) can be
    removed in the future.

2) [P 3] add WQ_PERCPU to remaining alloc_workqueue() users

    With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND),
    any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND
    must now use WQ_PERCPU.

    WQ_UNBOUND will be removed in future.

For more information:
    https://lore.kernel.org/all/20250221112003.1dSuoGyc@linutronix.de/


This patch (of 3):

This patch continues the effort to refactor workqueue APIs, which has
begun with the changes introducing new workqueues and a new
alloc_workqueue flag:

   commit 128ea9f6cc ("workqueue: Add system_percpu_wq and system_dfl_wq")
   commit 930c2ea566 ("workqueue: Add new WQ_PERCPU flag")

The point of the refactoring is to eventually alter the default behavior
of workqueues to become unbound by default so that their workload
placement is optimized by the scheduler.

Before that to happen, workqueue users must be converted to the better
named new workqueues with no intended behaviour changes:

   system_wq -> system_percpu_wq
   system_unbound_wq -> system_dfl_wq

This way the old obsolete workqueues (system_wq, system_unbound_wq) can be
removed in the future.

Link: https://lkml.kernel.org/r/20260113114630.152942-1-marco.crivellari@suse.com
Link: https://lore.kernel.org/all/20250221112003.1dSuoGyc@linutronix.de/
Link: https://lkml.kernel.org/r/20260113114630.152942-2-marco.crivellari@suse.com
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Suggested-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lai jiangshan <jiangshanlai@gmail.com>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Marco Elver <elver@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-31 14:22:39 -08:00
Shakeel Butt
95296536eb memcg: rename mem_cgroup_ino() to mem_cgroup_id()
Rename mem_cgroup_ino() to mem_cgroup_id() and mem_cgroup_get_from_ino()
to mem_cgroup_get_from_id().  These functions now use cgroup IDs (from
cgroup_id()) rather than inode numbers, so the names should reflect that.

[shakeel.butt@linux.dev: replace ino with id, per SeongJae]
  Link: https://lkml.kernel.org/r/flkqanhyettp5uq22bjwg37rtmnpeg3mghznsylxcxxgaafpl4@nov2x7tagma7
[akpm@linux-foundation.org: build fix]
Link: https://lkml.kernel.org/r/20251225232116.294540-9-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26 20:02:25 -08:00
Shakeel Butt
2202e3a8cb memcg: remove unused mem_cgroup_id() and mem_cgroup_from_id()
Now that all callers have been converted to use either:
 - The private ID APIs (mem_cgroup_private_id/mem_cgroup_from_private_id)
   for internal kernel objects that outlive their cgroup
 - The public cgroup ID APIs (mem_cgroup_ino/mem_cgroup_get_from_ino)
   for external interfaces

Remove the unused wrapper functions mem_cgroup_id() and
mem_cgroup_from_id() along with their !CONFIG_MEMCG stubs.

Link: https://lkml.kernel.org/r/20251225232116.294540-8-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: SeongJae Park <sj@kernel.org>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26 20:02:25 -08:00
Shakeel Butt
ea73e36471 memcg: use cgroup_id() instead of cgroup_ino() for memcg ID
Switch mem_cgroup_ino() from using cgroup_ino() to cgroup_id().  The
cgroup_ino() returns the kernfs inode number while cgroup_id() returns the
kernfs node ID.  For 64-bit systems, they are the same.  Also
cgroup_get_from_id() expects 64-bit node ID which is called by
mem_cgroup_get_from_ino().

Change the type from unsigned long to u64 to match cgroup_id()'s return
type, and update the format specifiers accordingly.

Note that the names mem_cgroup_ino() and mem_cgroup_get_from_ino() are now
misnomers since they deal with cgroup IDs rather than inode numbers.  A
follow-up patch will rename them.

Link: https://lkml.kernel.org/r/20251225232116.294540-5-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: SeongJae Park <sj@kernel.org>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26 20:02:24 -08:00
Shakeel Butt
510e129002 memcg: mem_cgroup_get_from_ino() returns NULL on error
Change mem_cgroup_get_from_ino() to return NULL on error instead of
ERR_PTR values.  This simplifies the API: NULL indicates failure, and a
valid pointer indicates success with a CSS reference held that the caller
must release via mem_cgroup_put().

Link: https://lkml.kernel.org/r/20251225232116.294540-4-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: SeongJae Park <sj@kernel.org>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26 20:02:24 -08:00
Shakeel Butt
1d89d7fd59 memcg: expose mem_cgroup_ino() and mem_cgroup_get_from_ino() unconditionally
Remove the CONFIG_SHRINKER_DEBUG guards around mem_cgroup_ino() and
mem_cgroup_get_from_ino().  These APIs provide a way to get a memcg's
cgroup inode number and to look up a memcg from an inode number
respectively.

Making these functions unconditionally available allows other in-kernel
users to leverage them without requiring CONFIG_SHRINKER_DEBUG to be
enabled.

No functional change for existing users.

Link: https://lkml.kernel.org/r/20251225232116.294540-3-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: SeongJae Park <sj@kernel.org>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26 20:02:23 -08:00
Shakeel Butt
e77786b468 memcg: introduce private id API for in-kernel users
Patch series "memcg: separate private and public ID namespaces".

The memory cgroup subsystem maintains a private ID infrastructure that
is decoupled from the cgroup IDs. This private ID system exists because
some kernel objects (like swap entries and shadow entries in the
workingset code) can outlive the cgroup they were associated with.
The motivation is best described in commit 73f576c04b ("mm:
memcontrol: fix cgroup creation failure after many small jobs").

Unfortunately, some in-kernel users (DAMON, LRU gen debugfs interface,
shrinker debugfs) started exposing these private IDs to userspace.
This is problematic because:

1. The private IDs are internal implementation details that could change
2. Userspace already has access to cgroup IDs through the cgroup
   filesystem
3. Using different ID namespaces in different interfaces is confusing

This series cleans up the memcg ID infrastructure by:

1. Explicitly marking the private ID APIs with "private" in their names
   to make it clear they are for internal use only (swap/workingset)

2. Making the public cgroup ID APIs (mem_cgroup_id/mem_cgroup_get_from_id)
   unconditionally available

3. Converting DAMON, LRU gen, and shrinker debugfs interfaces to use
   the public cgroup IDs instead of the private IDs

4. Removing the now-unused wrapper functions and renaming the public
   APIs for clarity

After this series:
- mem_cgroup_private_id() / mem_cgroup_from_private_id() are used for
  internal kernel objects that outlive their cgroup (swap, workingset)
- mem_cgroup_id() / mem_cgroup_get_from_id() return the public cgroup ID
  (from cgroup_id()) for use in userspace-facing interfaces


This patch (of 8):

The memory cgroup maintains a private ID infrastructure decoupled from the
cgroup IDs for swapout records and shadow entries.  The main motivation of
this private ID infra is best described in the commit 73f576c04b ("mm:
memcontrol: fix cgroup creation failure after many small jobs").

Unfortunately some users have started exposing these private IDs to the
userspace where they should have used the cgroup IDs which are already
exposed to the userspace.  Let's rename the memcg ID APIs to explicitly
mark them private.

No functional change is intended.

Link: https://lkml.kernel.org/r/20251225232116.294540-1-shakeel.butt@linux.dev
Link: https://lkml.kernel.org/r/20251225232116.294540-2-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: SeongJae Park <sj@kernel.org>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26 20:02:23 -08:00
Kevin Lourenco
62451ae347 mm: fix minor spelling mistakes in comments
Correct several typos in comments across files in mm/

[akpm@linux-foundation.org: also fix comment grammar, per SeongJae]
Link: https://lkml.kernel.org/r/20251218150906.25042-1-klourencodev@gmail.com
Signed-off-by: Kevin Lourenco <klourencodev@gmail.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20 19:24:48 -08:00
Johannes Weiner
16cc8b9396 mm: memcontrol: rename mem_cgroup_from_slab_obj()
In addition to slab objects, this function is used for resolving non-slab
kernel pointers.  This has caused confusion in recent refactoring work. 
Rename it to mem_cgroup_from_virt(), sticking with terminology established
by the virt_to_<foo>() converters.

Link: https://lore.kernel.org/linux-mm/20251113161424.GB3465062@cmpxchg.org/
Link: https://lkml.kernel.org/r/20251210154301.720133-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20 19:24:42 -08:00
Chen Ridong
055059ed72 memcg: remove mem_cgroup_size()
The mem_cgroup_size helper is used only in apply_proportional_protection
to read the current memory usage.  Its semantics are unclear and
inconsistent with other sites, which directly call page_counter_read for
the same purpose.

Remove this helper and get its usage via mem_cgroup_protection for
clarity.  Additionally, rename the local variable 'cgroup_size' to 'usage'
to better reflect its meaning.

No functional changes intended.

Link: https://lkml.kernel.org/r/20251211013019.2080004-3-chenridong@huaweicloud.com
Signed-off-by: Chen Ridong <chenridong@huawei.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Lu Jialin <lujialin4@huawei.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20 19:24:42 -08:00
Chen Ridong
558605a530 memcg: move mem_cgroup_usage memcontrol-v1.c
Patch series "memcg cleanups", v3.

Two code moves/removals with no behavior change.


This patch (of 2):

Currently, mem_cgroup_usage is only used for v1, just move it to
memcontrol-v1.c

Link: https://lkml.kernel.org/r/20251211013019.2080004-1-chenridong@huaweicloud.com
Link: https://lkml.kernel.org/r/20251211013019.2080004-2-chenridong@huaweicloud.com
Signed-off-by: Chen Ridong <chenridong@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Michal Koutný <mkoutny@suse.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Lu Jialin <lujialin4@huawei.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20 19:24:41 -08:00
Alexei Starovoitov
e3d0dbb3b5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after rc5
Cross-merge BPF and other fixes after downstream PR.

No conflicts.

Adjacent:
Auto-merging MAINTAINERS
Auto-merging Makefile
Auto-merging kernel/bpf/verifier.c
Auto-merging kernel/sched/ext.c
Auto-merging mm/memcontrol.c

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-01-14 15:22:01 -08:00
Shakeel Butt
6db12d5c47 mm: memcg: fix unit conversion for K() macro in OOM log
The commit bc8e51c05a ("mm: memcg: dump memcg protection info on oom or
alloc failures") added functionality to dump memcg protections on OOM or
allocation failures.  It uses K() macro to dump the information and passes
bytes to the macro.  However the macro take number of pages instead of
bytes.  It is defined as:

 #define K(x) ((x) << (PAGE_SHIFT-10))

Let's fix this.

Link: https://lkml.kernel.org/r/20251216212054.484079-1-shakeel.butt@linux.dev
Fixes: bc8e51c05a ("mm: memcg: dump memcg protection info on oom or alloc failures")
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Reported-by: Chris Mason <clm@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-12-23 11:23:15 -08:00
Roman Gushchin
99430ab8b8 mm: introduce BPF kfuncs to access memcg statistics and events
Introduce BPF kfuncs to conveniently access memcg data:
  - bpf_mem_cgroup_vm_events(),
  - bpf_mem_cgroup_memory_events(),
  - bpf_mem_cgroup_usage(),
  - bpf_mem_cgroup_page_state(),
  - bpf_mem_cgroup_flush_stats().

These functions are useful for implementing BPF OOM policies, but
also can be used to accelerate access to the memcg data. Reading
it through cgroupfs is much more expensive, roughly 5x, mostly
because of the need to convert the data into the text and back.

JP Kobryn:
An experiment was setup to compare the performance of a program that
uses the traditional method of reading memory.stat vs a program using
the new kfuncs. The control program opens up the root memory.stat file
and for 1M iterations reads, converts the string values to numeric data,
then seeks back to the beginning. The experimental program sets up the
requisite libbpf objects and for 1M iterations invokes a bpf program
which uses the kfuncs to fetch all available stats for node_stat_item,
memcg_stat_item, and vm_event_item types.

The results showed a significant perf benefit on the experimental side,
outperforming the control side by a margin of 93%. In kernel mode,
elapsed time was reduced by 80%, while in user mode, over 99% of time
was saved.

control: elapsed time
real    0m38.318s
user    0m25.131s
sys     0m13.070s

experiment: elapsed time
real    0m2.789s
user    0m0.187s
sys     0m2.512s

control: perf data
33.43% a.out libc.so.6         [.] __vfscanf_internal
 6.88% a.out [kernel.kallsyms] [k] vsnprintf
 6.33% a.out libc.so.6         [.] _IO_fgets
 5.51% a.out [kernel.kallsyms] [k] format_decode
 4.31% a.out libc.so.6         [.] __GI_____strtoull_l_internal
 3.78% a.out [kernel.kallsyms] [k] string
 3.53% a.out [kernel.kallsyms] [k] number
 2.71% a.out libc.so.6         [.] _IO_sputbackc
 2.41% a.out [kernel.kallsyms] [k] strlen
 1.98% a.out a.out             [.] main
 1.70% a.out libc.so.6         [.] _IO_getline_info
 1.51% a.out libc.so.6         [.] __isoc99_sscanf
 1.47% a.out [kernel.kallsyms] [k] memory_stat_format
 1.47% a.out [kernel.kallsyms] [k] memcpy_orig
 1.41% a.out [kernel.kallsyms] [k] seq_buf_printf

experiment: perf data
10.55% memcgstat bpf_prog_..._query [k] bpf_prog_16aab2f19fa982a7_query
 6.90% memcgstat [kernel.kallsyms]  [k] memcg_page_state_output
 3.55% memcgstat [kernel.kallsyms]  [k] _raw_spin_lock
 3.12% memcgstat [kernel.kallsyms]  [k] memcg_events
 2.87% memcgstat [kernel.kallsyms]  [k] __memcg_slab_post_alloc_hook
 2.73% memcgstat [kernel.kallsyms]  [k] kmem_cache_free
 2.70% memcgstat [kernel.kallsyms]  [k] entry_SYSRETQ_unsafe_stack
 2.25% memcgstat [kernel.kallsyms]  [k] __memcg_slab_free_hook
 2.06% memcgstat [kernel.kallsyms]  [k] get_page_from_freelist

Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Co-developed-by: JP Kobryn <inwardvessel@gmail.com>
Signed-off-by: JP Kobryn <inwardvessel@gmail.com>
Link: https://lore.kernel.org/r/20251223044156.208250-5-roman.gushchin@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-12-22 22:20:22 -08:00
Chen Ridong
82d7e59ea7 cgroup: switch to css_is_online() helper
Use the new css_is_online() helper that has been introduced to check css
online state, instead of testing the CSS_ONLINE flag directly. This
improves readability and centralizes the state check logic.

No functional changes intended.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Tejun Heo <tj@kernel.org>
2025-12-08 09:02:38 -10:00
Linus Torvalds
7203ca412f Significant patch series in this merge are as follows:
- The 10 patch series "__vmalloc()/kvmalloc() and no-block support" from
   Uladzislau Rezki reworks the vmalloc() code to support non-blocking
   allocations (GFP_ATOIC, GFP_NOWAIT).
 
 - The 2 patch series "ksm: fix exec/fork inheritance" from xu xin fixes
   a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not inherited
   across fork/exec.
 
 - The 4 patch series "mm/zswap: misc cleanup of code and documentations"
   from SeongJae Park does some light maintenance work on the zswap code.
 
 - The 5 patch series "mm/page_owner: add debugfs files 'show_handles'
   and 'show_stacks_handles'" from Mauricio Faria de Oliveira enhances the
   /sys/kernel/debug/page_owner debug feature.  It adds unique identifiers
   to differentiate the various stack traces so that userspace monitoring
   tools can better match stack traces over time.
 
 - The 2 patch series "mm/page_alloc: pcp->batch cleanups" from Joshua
   Hahn makes some minor alterations to the page allocator's per-cpu-pages
   feature.
 
 - The 2 patch series "Improve UFFDIO_MOVE scalability by removing
   anon_vma lock" from Lokesh Gidra addresses a scalability issue in
   userfaultfd's UFFDIO_MOVE operation.
 
 - The 2 patch series "kasan: cleanups for kasan_enabled() checks" from
   Sabyrzhan Tasbolatov performs some cleanup in the KASAN code.
 
 - The 2 patch series "drivers/base/node: fold node register and
   unregister functions" from Donet Tom cleans up the NUMA node handling
   code a little.
 
 - The 4 patch series "mm: some optimizations for prot numa" from Kefeng
   Wang provides some cleanups and small optimizations to the NUMA
   allocation hinting code.
 
 - The 5 patch series "mm/page_alloc: Batch callers of
   free_pcppages_bulk" from Joshua Hahn addresses long lock hold times at
   boot on large machines.  These were causing (harmless) softlockup
   warnings.
 
 - The 2 patch series "optimize the logic for handling dirty file folios
   during reclaim" from Baolin Wang removes some now-unnecessary work from
   page reclaim.
 
 - The 10 patch series "mm/damon: allow DAMOS auto-tuned for per-memcg
   per-node memory usage" from SeongJae Park enhances the DAMOS auto-tuning
   feature.
 
 - The 2 patch series "mm/damon: fixes for address alignment issues in
   DAMON_LRU_SORT and DAMON_RECLAIM" from Quanmin Yan fixes DAMON_LRU_SORT
   and DAMON_RECLAIM with certain userspace configuration.
 
 - The 15 patch series "expand mmap_prepare functionality, port more
   users" from Lorenzo Stoakes enhances the new(ish)
   file_operations.mmap_prepare() method and ports additional callsites
   from the old ->mmap() over to ->mmap_prepare().
 
 - The 8 patch series "Fix stale IOTLB entries for kernel address space"
   from Lu Baolu fixes a bug (and possible security issue on non-x86) in
   the IOMMU code.  In some situations the IOMMU could be left hanging onto
   a stale kernel pagetable entry.
 
 - The 4 patch series "mm/huge_memory: cleanup __split_unmapped_folio()"
   from Wei Yang cleans up and optimizes the folio splitting code.
 
 - The 5 patch series "mm, swap: misc cleanup and bugfix" from Kairui
   Song implements some cleanups and a minor fix in the swap discard code.
 
 - The 8 patch series "mm/damon: misc documentation fixups" from SeongJae
   Park does as advertised.
 
 - The 9 patch series "mm/damon: support pin-point targets removal" from
   SeongJae Park permits userspace to remove a specific monitoring target
   in the middle of the current targets list.
 
 - The 2 patch series "mm: MISC follow-up patches for linux/pgalloc.h"
   from Harry Yoo implements a couple of cleanups related to mm header file
   inclusion.
 
 - The 2 patch series "mm/swapfile.c: select swap devices of default
   priority round robin" from Baoquan He improves the selection of swap
   devices for NUMA machines.
 
 - The 3 patch series "mm: Convert memory block states (MEM_*) macros to
   enums" from Israel Batista changes the memory block labels from macros
   to enums so they will appear in kernel debug info.
 
 - The 3 patch series "ksm: perform a range-walk to jump over holes in
   break_ksm" from Pedro Demarchi Gomes addresses an inefficiency when KSM
   unmerges an address range.
 
 - The 22 patch series "mm/damon/tests: fix memory bugs in kunit tests"
   from SeongJae Park fixes leaks and unhandled malloc() failures in DAMON
   userspace unit tests.
 
 - The 2 patch series "some cleanups for pageout()" from Baolin Wang
   cleans up a couple of minor things in the page scanner's
   writeback-for-eviction code.
 
 - The 2 patch series "mm/hugetlb: refactor sysfs/sysctl interfaces" from
   Hui Zhu moves hugetlb's sysfs/sysctl handling code into a new file.
 
 - The 9 patch series "introduce VM_MAYBE_GUARD and make it sticky" from
   Lorenzo Stoakes makes the VMA guard regions available in /proc/pid/smaps
   and improves the mergeability of guarded VMAs.
 
 - The 2 patch series "mm: perform guard region install/remove under VMA
   lock" from Lorenzo Stoakes reduces mmap lock contention for callers
   performing VMA guard region operations.
 
 - The 2 patch series "vma_start_write_killable" from Matthew Wilcox
   starts work in permitting applications to be killed when they are
   waiting on a read_lock on the VMA lock.
 
 - The 11 patch series "mm/damon/tests: add more tests for online
   parameters commit" from SeongJae Park adds additional userspace testing
   of DAMON's "commit" feature.
 
 - The 9 patch series "mm/damon: misc cleanups" from SeongJae Park does
   that.
 
 - The 2 patch series "make VM_SOFTDIRTY a sticky VMA flag" from Lorenzo
   Stoakes addresses the possible loss of a VMA's VM_SOFTDIRTY flag when
   that VMA is merged with another.
 
 - The 16 patch series "mm: support device-private THP" from Balbir Singh
   introduces support for Transparent Huge Page (THP) migration in zone
   device-private memory.
 
 - The 3 patch series "Optimize folio split in memory failure" from Zi
   Yan optimizes folio split operations in the memory failure code.
 
 - The 2 patch series "mm/huge_memory: Define split_type and consolidate
   split support checks" from Wei Yang provides some more cleanups in the
   folio splitting code.
 
 - The 16 patch series "mm: remove is_swap_[pte, pmd]() + non-swap
   entries, introduce leaf entries" from Lorenzo Stoakes cleans up our
   handling of pagetable leaf entries by introducing the concept of
   'software leaf entries', of type softleaf_t.
 
 - The 4 patch series "reparent the THP split queue" from Muchun Song
   reparents the THP split queue to its parent memcg.  This is in
   preparation for addressing the long-standing "dying memcg" problem,
   wherein dead memcg's linger for too long, consuming memory resources.
 
 - The 3 patch series "unify PMD scan results and remove redundant
   cleanup" from Wei Yang does a little cleanup in the hugepage collapse
   code.
 
 - The 6 patch series "zram: introduce writeback bio batching" from
   Sergey Senozhatsky improves zram writeback efficiency by introducing
   batched bio writeback support.
 
 - The 4 patch series "memcg: cleanup the memcg stats interfaces" from
   Shakeel Butt cleans up our handling of the interrupt safety of some
   memcg stats.
 
 - The 4 patch series "make vmalloc gfp flags usage more apparent" from
   Vishal Moola cleans up vmalloc's handling of incoming GFP flags.
 
 - The 6 patch series "mm: Add soft-dirty and uffd-wp support for RISC-V"
   from Chunyan Zhang teches soft dirty and userfaultfd write protect
   tracking to use RISC-V's Svrsw60t59b extension.
 
 - The 5 patch series "mm: swap: small fixes and comment cleanups" from
   Youngjun Park fixes a small bug and cleans up some of the swap code.
 
 - The 4 patch series "initial work on making VMA flags a bitmap" from
   Lorenzo Stoakes starts work on converting the vma struct's flags to a
   bitmap, so we stop running out of them, especially on 32-bit.
 
 - The 2 patch series "mm/swapfile: fix and cleanup swap list iterations"
   from Youngjun Park addresses a possible bug in the swap discard code and
   cleans things up a little.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaTEb0wAKCRDdBJ7gKXxA
 jjfIAP94W4EkCCwNOupnChoG+YWw/JW21anXt5NN+i5svn1yugEAwzvv6A+cAFng
 o+ug/fyrfPZG7PLp2R8WFyGIP0YoBA4=
 =IUzS
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

  "__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki)
     Rework the vmalloc() code to support non-blocking allocations
     (GFP_ATOIC, GFP_NOWAIT)

  "ksm: fix exec/fork inheritance" (xu xin)
     Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not
     inherited across fork/exec

  "mm/zswap: misc cleanup of code and documentations" (SeongJae Park)
     Some light maintenance work on the zswap code

  "mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira)
     Enhance the /sys/kernel/debug/page_owner debug feature by adding
     unique identifiers to differentiate the various stack traces so
     that userspace monitoring tools can better match stack traces over
     time

  "mm/page_alloc: pcp->batch cleanups" (Joshua Hahn)
     Minor alterations to the page allocator's per-cpu-pages feature

  "Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra)
     Address a scalability issue in userfaultfd's UFFDIO_MOVE operation

  "kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov)

  "drivers/base/node: fold node register and unregister functions" (Donet Tom)
     Clean up the NUMA node handling code a little

  "mm: some optimizations for prot numa" (Kefeng Wang)
     Cleanups and small optimizations to the NUMA allocation hinting
     code

  "mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn)
     Address long lock hold times at boot on large machines. These were
     causing (harmless) softlockup warnings

  "optimize the logic for handling dirty file folios during reclaim" (Baolin Wang)
     Remove some now-unnecessary work from page reclaim

  "mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park)
     Enhance the DAMOS auto-tuning feature

  "mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan)
     Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace
     configuration

  "expand mmap_prepare functionality, port more users" (Lorenzo Stoakes)
     Enhance the new(ish) file_operations.mmap_prepare() method and port
     additional callsites from the old ->mmap() over to ->mmap_prepare()

  "Fix stale IOTLB entries for kernel address space" (Lu Baolu)
     Fix a bug (and possible security issue on non-x86) in the IOMMU
     code. In some situations the IOMMU could be left hanging onto a
     stale kernel pagetable entry

  "mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang)
     Clean up and optimize the folio splitting code

  "mm, swap: misc cleanup and bugfix" (Kairui Song)
     Some cleanups and a minor fix in the swap discard code

  "mm/damon: misc documentation fixups" (SeongJae Park)

  "mm/damon: support pin-point targets removal" (SeongJae Park)
     Permit userspace to remove a specific monitoring target in the
     middle of the current targets list

  "mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo)
     A couple of cleanups related to mm header file inclusion

  "mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He)
     improve the selection of swap devices for NUMA machines

  "mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista)
     Change the memory block labels from macros to enums so they will
     appear in kernel debug info

  "ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes)
     Address an inefficiency when KSM unmerges an address range

  "mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park)
     Fix leaks and unhandled malloc() failures in DAMON userspace unit
     tests

  "some cleanups for pageout()" (Baolin Wang)
     Clean up a couple of minor things in the page scanner's
     writeback-for-eviction code

  "mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu)
     Move hugetlb's sysfs/sysctl handling code into a new file

  "introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes)
     Make the VMA guard regions available in /proc/pid/smaps and
     improves the mergeability of guarded VMAs

  "mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes)
     Reduce mmap lock contention for callers performing VMA guard region
     operations

  "vma_start_write_killable" (Matthew Wilcox)
     Start work on permitting applications to be killed when they are
     waiting on a read_lock on the VMA lock

  "mm/damon/tests: add more tests for online parameters commit" (SeongJae Park)
     Add additional userspace testing of DAMON's "commit" feature

  "mm/damon: misc cleanups" (SeongJae Park)

  "make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes)
     Address the possible loss of a VMA's VM_SOFTDIRTY flag when that
     VMA is merged with another

  "mm: support device-private THP" (Balbir Singh)
     Introduce support for Transparent Huge Page (THP) migration in zone
     device-private memory

  "Optimize folio split in memory failure" (Zi Yan)

  "mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang)
     Some more cleanups in the folio splitting code

  "mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes)
     Clean up our handling of pagetable leaf entries by introducing the
     concept of 'software leaf entries', of type softleaf_t

  "reparent the THP split queue" (Muchun Song)
     Reparent the THP split queue to its parent memcg. This is in
     preparation for addressing the long-standing "dying memcg" problem,
     wherein dead memcg's linger for too long, consuming memory
     resources

  "unify PMD scan results and remove redundant cleanup" (Wei Yang)
     A little cleanup in the hugepage collapse code

  "zram: introduce writeback bio batching" (Sergey Senozhatsky)
     Improve zram writeback efficiency by introducing batched bio
     writeback support

  "memcg: cleanup the memcg stats interfaces" (Shakeel Butt)
     Clean up our handling of the interrupt safety of some memcg stats

  "make vmalloc gfp flags usage more apparent" (Vishal Moola)
     Clean up vmalloc's handling of incoming GFP flags

  "mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang)
     Teach soft dirty and userfaultfd write protect tracking to use
     RISC-V's Svrsw60t59b extension

  "mm: swap: small fixes and comment cleanups" (Youngjun Park)
     Fix a small bug and clean up some of the swap code

  "initial work on making VMA flags a bitmap" (Lorenzo Stoakes)
     Start work on converting the vma struct's flags to a bitmap, so we
     stop running out of them, especially on 32-bit

  "mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park)
     Address a possible bug in the swap discard code and clean things
     up a little

[ This merge also reverts commit ebb9aeb980 ("vfio/nvgrace-gpu:
  register device memory for poison handling") because it looks
  broken to me, I've asked for clarification   - Linus ]

* tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
  mm: fix vma_start_write_killable() signal handling
  mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate
  mm/swapfile: fix list iteration when next node is removed during discard
  fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling
  mm/kfence: add reboot notifier to disable KFENCE on shutdown
  memcg: remove inc/dec_lruvec_kmem_state helpers
  selftests/mm/uffd: initialize char variable to Null
  mm: fix DEBUG_RODATA_TEST indentation in Kconfig
  mm: introduce VMA flags bitmap type
  tools/testing/vma: eliminate dependency on vma->__vm_flags
  mm: simplify and rename mm flags function for clarity
  mm: declare VMA flags by bit
  zram: fix a spelling mistake
  mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity
  mm/vmscan: skip increasing kswapd_failures when reclaim was boosted
  pagemap: update BUDDY flag documentation
  mm: swap: remove scan_swap_map_slots() references from comments
  mm: swap: change swap_alloc_slow() to void
  mm, swap: remove redundant comment for read_swap_cache_async
  mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational
  ...
2025-12-05 13:52:43 -08:00
Shakeel Butt
c1bd09994c memcg: remove __lruvec_stat_mod_folio
__lruvec_stat_mod_folio() is already safe against irqs, so there is no
need to have a separate interface (i.e.  lruvec_stat_mod_folio) which
wraps calls to it with irq disabling and reenabling.  Let's rename
__lruvec_stat_mod_folio() to lruvec_stat_mod_folio().

Link: https://lkml.kernel.org/r/20251110232008.1352063-5-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24 15:08:54 -08:00
Shakeel Butt
5b3eb779a2 memcg: remove __mod_lruvec_state
__mod_lruvec_state() is already safe against irqs, so there is no need to
have a separate interface (i.e.  mod_lruvec_state) which wraps calls to it
with irq disabling and reenabling.  Let's rename __mod_lruvec_state() to
mod_lruvec_state().

Link: https://lkml.kernel.org/r/20251110232008.1352063-4-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24 15:08:54 -08:00
Shakeel Butt
469241fe76 memcg: remove __mod_lruvec_kmem_state
__mod_lruvec_kmem_state() is already safe against irqs, so there is no
need to have a separate interface (i.e.  mod_lruvec_kmem_state) which
wraps calls to it with irq disabling and reenabling.  Let's rename
__mod_lruvec_kmem_state() to mod_lruvec_kmem_state().

Link: https://lkml.kernel.org/r/20251110232008.1352063-3-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Reviewed-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24 15:08:54 -08:00
Shakeel Butt
7e44d00a13 memcg: use mod_node_page_state to update stats
Patch series "memcg: cleanup the memcg stats interfaces".

The memcg stats are safe against irq (and nmi) context and thus does not
require disabling irqs.  However for some stats which are also maintained
at node level, it is using irq unsafe interface and thus requiring the
users to still disables irqs or use interfaces which explicitly disables
irqs.  Let's move memcg code to use irq safe node level stats function
which is already optimized for architectures with HAVE_CMPXCHG_LOCAL (all
major ones), so there will not be any performance penalty for its usage.


This patch (of 4):

The memcg stats are safe against irq (and nmi) context and thus does not
require disabling irqs.  However some code paths for memcg stats also
update the node level stats and use irq unsafe interface and thus require
the users to disable irqs.  However node level stats, on architectures
with HAVE_CMPXCHG_LOCAL (all major ones), has interface which does not
require irq disabling.  Let's move memcg stats code to start using that
interface for node level stats.

Link: https://lkml.kernel.org/r/20251110232008.1352063-1-shakeel.butt@linux.dev
Link: https://lkml.kernel.org/r/20251110232008.1352063-2-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24 15:08:53 -08:00
Qi Zheng
46156dba32 mm: thp: reparent the split queue during memcg offline
Similar to list_lru, the split queue is relatively independent and does
not need to be reparented along with objcg and LRU folios (holding objcg
lock and lru lock).  So let's apply the similar mechanism as list_lru to
reparent the split queue separately when memcg is offine.

This is also a preparation for reparenting LRU folios.

Link: https://lkml.kernel.org/r/8703f907c4d1f7e8a2ef2bfed3036a84fa53028b.1762762324.git.zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24 15:08:52 -08:00
Shakeel Butt
bc8e51c05a mm: memcg: dump memcg protection info on oom or alloc failures
Currently kernel dumps memory state on oom and allocation failures.  One
of the question usually raised on those dumps is why the kernel has not
reclaimed the reclaimable memory instead of triggering oom.  One potential
reason is the usage of memory protection provided by memcg.  So, let's
also dump the memory protected by the memcg in such reports to ease the
debugging.

Link: https://lkml.kernel.org/r/20251107234041.3632644-1-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-20 13:43:59 -08:00
Shakeel Butt
5ff592bec7 memcg: manually uninline __memcg_memory_event
__memcg_memory_event() has been unnecessarily marked inline even when it
is not really performance critical.  It is usually called to track extreme
conditions.  Over the time, it has evolved to include more functionality
and inlining it is causing more harm.

Before the patch:
$ size mm/memcontrol.o net/ipv4/tcp_input.o net/ipv4/tcp_output.o
   text    data     bss     dec     hex filename
  35645   10574    4192   50411    c4eb mm/memcontrol.o
  54738    1658       0   56396    dc4c net/ipv4/tcp_input.o
  34644    1065       0   35709    8b7d net/ipv4/tcp_output.o

After the patch:
$ size mm/memcontrol.o net/ipv4/tcp_input.o net/ipv4/tcp_output.o
   text    data     bss     dec     hex filename
  35137   10446    4192   49775    c26f mm/memcontrol.o
  54322    1562       0   55884    da4c net/ipv4/tcp_input.o
  34492    1017       0   35509    8ab5 net/ipv4/tcp_output.o

[akpm@linux-foundation.org: use EXPORT_SYMBOL_GPL for __memcg_memory_event, per Michal and Christoph]
Link: https://lkml.kernel.org/r/20251021234425.1885471-1-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: SeongJae Park <sj@kernel.org>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16 17:28:16 -08:00
Shakeel Butt
d929525c2e memcg: net: track network throttling due to memcg memory pressure
The kernel can throttle network sockets if the memory cgroup associated
with the corresponding socket is under memory pressure.  The throttling
actions include clamping the transmit window, failing to expand receive or
send buffers, aggressively prune out-of-order receive queue, FIN deferred
to a retransmitted packet and more.  Let's add memcg metric to track such
throttling actions.

At the moment memcg memory pressure is defined through vmpressure and in
future it may be defined using PSI or we may add more flexible way for the
users to define memory pressure, maybe through ebpf.  However the
potential throttling actions will remain the same, so this newly
introduced metric will continue to track throttling actions irrespective
of how memcg memory pressure is defined.

Link: https://lkml.kernel.org/r/20251016161035.86161-1-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Daniel Sedlak <daniel.sedlak@cdn77.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kacinski <kuba@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <horms@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16 17:28:06 -08:00
SeongJae Park
f7ed6bf237 mm/zswap: fix typos: s/zwap/zswap/
As the subject says.

Link: https://lkml.kernel.org/r/20251003203851.43128-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Acked-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Acked-by: Nhat Pham <nphamcs@gmail.com>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16 17:27:57 -08:00
Matthew Wilcox (Oracle)
b8557d109e memcg: Convert mem_cgroup_from_obj_folio() to mem_cgroup_from_obj_slab()
In preparation for splitting struct slab from struct page and struct
folio, convert the pointer to a slab rather than a folio.  This means
we can end up passing a NULL slab pointer to mem_cgroup_from_obj_slab()
if the pointer is not to a page allocated to slab, and we handle that
appropriately by returning NULL.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: cgroups@vger.kernel.org
Link: https://patch.msgid.link/20251113000932.1589073-15-willy@infradead.org
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2025-11-13 20:23:09 +01:00
Shakeel Butt
fcc0669c5a memcg: skip cgroup_file_notify if spinning is not allowed
Generally memcg charging is allowed from all the contexts including NMI
where even spinning on spinlock can cause locking issues.  However one
call chain was missed during the addition of memcg charging from any
context support.  That is try_charge_memcg() -> memcg_memory_event() ->
cgroup_file_notify().

The possible function call tree under cgroup_file_notify() can acquire
many different spin locks in spinning mode.  Some of them are
cgroup_file_kn_lock, kernfs_notify_lock, pool_workqeue's lock.  So, let's
just skip cgroup_file_notify() from memcg charging if the context does not
allow spinning.

Alternative approach was also explored where instead of skipping
cgroup_file_notify(), we defer the memcg event processing to irq_work [1].
However it adds complexity and it was decided to keep things simple until
we need more memcg events with !allow_spinning requirement.

Link: https://lore.kernel.org/all/5qi2llyzf7gklncflo6gxoozljbm4h3tpnuv4u4ej4ztysvi6f@x44v7nz2wdzd/ [1]
Link: https://lkml.kernel.org/r/20250922220203.261714-1-shakeel.butt@linux.dev
Fixes: 3ac4638a73 ("memcg: make memcg_rstat_updated nmi safe")
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Closes: https://lore.kernel.org/all/20250905061919.439648-1-yepeilin@google.com/
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peilin Ye <yepeilin@google.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-07 14:01:11 -07:00
Linus Torvalds
8804d970fa Summary of significant series in this pull request:
- The 3 patch series "mm, swap: improve cluster scan strategy" from
   Kairui Song improves performance and reduces the failure rate of swap
   cluster allocation.
 
 - The 4 patch series "support large align and nid in Rust allocators"
   from Vitaly Wool permits Rust allocators to set NUMA node and large
   alignment when perforning slub and vmalloc reallocs.
 
 - The 2 patch series "mm/damon/vaddr: support stat-purpose DAMOS" from
   Yueyang Pan extend DAMOS_STAT's handling of the DAMON operations sets
   for virtual address spaces for ops-level DAMOS filters.
 
 - The 3 patch series "execute PROCMAP_QUERY ioctl under per-vma lock"
   from Suren Baghdasaryan reduces mmap_lock contention during reads of
   /proc/pid/maps.
 
 - The 2 patch series "mm/mincore: minor clean up for swap cache
   checking" from Kairui Song performs some cleanup in the swap code.
 
 - The 11 patch series "mm: vm_normal_page*() improvements" from David
   Hildenbrand provides code cleanup in the pagemap code.
 
 - The 5 patch series "add persistent huge zero folio support" from
   Pankaj Raghav provides a block layer speedup by optionalls making the
   huge_zero_pagepersistent, instead of releasing it when its refcount
   falls to zero.
 
 - The 3 patch series "kho: fixes and cleanups" from Mike Rapoport adds a
   few touchups to the recently added Kexec Handover feature.
 
 - The 10 patch series "mm: make mm->flags a bitmap and 64-bit on all
   arches" from Lorenzo Stoakes turns mm_struct.flags into a bitmap.  To
   end the constant struggle with space shortage on 32-bit conflicting with
   64-bit's needs.
 
 - The 2 patch series "mm/swapfile.c and swap.h cleanup" from Chris Li
   cleans up some swap code.
 
 - The 7 patch series "selftests/mm: Fix false positives and skip
   unsupported tests" from Donet Tom fixes a few things in our selftests
   code.
 
 - The 7 patch series "prctl: extend PR_SET_THP_DISABLE to only provide
   THPs when advised" from David Hildenbrand "allows individual processes
   to opt-out of THP=always into THP=madvise, without affecting other
   workloads on the system".
 
   It's a long story - the [1/N] changelog spells out the considerations.
 
 - The 11 patch series "Add and use memdesc_flags_t" from Matthew Wilcox
   gets us started on the memdesc project.  Please see
   https://kernelnewbies.org/MatthewWilcox/Memdescs and
   https://blogs.oracle.com/linux/post/introducing-memdesc.
 
 - The 3 patch series "Tiny optimization for large read operations" from
   Chi Zhiling improves the efficiency of the pagecache read path.
 
 - The 5 patch series "Better split_huge_page_test result check" from Zi
   Yan improves our folio splitting selftest code.
 
 - The 2 patch series "test that rmap behaves as expected" from Wei Yang
   adds some rmap selftests.
 
 - The 3 patch series "remove write_cache_pages()" from Christoph Hellwig
   removes that function and converts its two remaining callers.
 
 - The 2 patch series "selftests/mm: uffd-stress fixes" from Dev Jain
   fixes some UFFD selftests issues.
 
 - The 3 patch series "introduce kernel file mapped folios" from Boris
   Burkov introduces the concept of "kernel file pages".  Using these
   permits btrfs to account its metadata pages to the root cgroup, rather
   than to the cgroups of random inappropriate tasks.
 
 - The 2 patch series "mm/pageblock: improve readability of some
   pageblock handling" from Wei Yang provides some readability improvements
   to the page allocator code.
 
 - The 11 patch series "mm/damon: support ARM32 with LPAE" from SeongJae
   Park teaches DAMON to understand arm32 highmem.
 
 - The 4 patch series "tools: testing: Use existing atomic.h for
   vma/maple tests" from Brendan Jackman performs some code cleanups and
   deduplication under tools/testing/.
 
 - The 2 patch series "maple_tree: Fix testing for 32bit compiles" from
   Liam Howlett fixes a couple of 32-bit issues in
   tools/testing/radix-tree.c.
 
 - The 2 patch series "kasan: unify kasan_enabled() and remove
   arch-specific implementations" from Sabyrzhan Tasbolatov moves KASAN
   arch-specific initialization code into a common arch-neutral
   implementation.
 
 - The 3 patch series "mm: remove zpool" from Johannes Weiner removes
   zspool - an indirection layer which now only redirects to a single thing
   (zsmalloc).
 
 - The 2 patch series "mm: task_stack: Stack handling cleanups" from
   Pasha Tatashin makes a couple of cleanups in the fork code.
 
 - The 37 patch series "mm: remove nth_page()" from David Hildenbrand
   makes rather a lot of adjustments at various nth_page() callsites,
   eventually permitting the removal of that undesirable helper function.
 
 - The 2 patch series "introduce kasan.write_only option in hw-tags" from
   Yeoreum Yun creates a KASAN read-only mode for ARM, using that
   architecture's memory tagging feature.  It is felt that a read-only mode
   KASAN is suitable for use in production systems rather than debug-only.
 
 - The 3 patch series "mm: hugetlb: cleanup hugetlb folio allocation"
   from Kefeng Wang does some tidying in the hugetlb folio allocation code.
 
 - The 12 patch series "mm: establish const-correctness for pointer
   parameters" from Max Kellermann makes quite a number of the MM API
   functions more accurate about the constness of their arguments.  This
   was getting in the way of subsystems (in this case CEPH) when they
   attempt to improving their own const/non-const accuracy.
 
 - The 7 patch series "Cleanup free_pages() misuse" from Vishal Moola
   fixes a number of code sites which were confused over when to use
   free_pages() vs __free_pages().
 
 - The 3 patch series "Add Rust abstraction for Maple Trees" from Alice
   Ryhl makes the mapletree code accessible to Rust.  Required by nouveau
   and by its forthcoming successor: the new Rust Nova driver.
 
 - The 2 patch series "selftests/mm: split_huge_page_test:
   split_pte_mapped_thp improvements" from David Hildenbrand adds a fix and
   some cleanups to the thp selftesting code.
 
 - The 14 patch series "mm, swap: introduce swap table as swap cache
   (phase I)" from Chris Li and Kairui Song is the first step along the
   path to implementing "swap tables" - a new approach to swap allocation
   and state tracking which is expected to yield speed and space
   improvements.  This patchset itself yields a 5-20% performance benefit
   in some situations.
 
 - The 3 patch series "Some ptdesc cleanups" from Matthew Wilcox utilizes
   the new memdesc layer to clean up the ptdesc code a little.
 
 - The 3 patch series "Fix va_high_addr_switch.sh test failure" from
   Chunyu Hu fixes some issues in our 5-level pagetable selftesting code.
 
 - The 2 patch series "Minor fixes for memory allocation profiling" from
   Suren Baghdasaryan addresses a couple of minor issues in relatively new
   memory allocation profiling feature.
 
 - The 3 patch series "Small cleanups" from Matthew Wilcox has a few
   cleanups in preparation for more memdesc work.
 
 - The 2 patch series "mm/damon: add addr_unit for DAMON_LRU_SORT and
   DAMON_RECLAIM" from Quanmin Yan makes some changes to DAMON in
   furtherance of supporting arm highmem.
 
 - The 2 patch series "selftests/mm: Add -Wunreachable-code and fix
   warnings" from Muhammad Anjum adds that compiler check to selftests code
   and fixes the fallout, by removing dead code.
 
 - The 10 patch series "Improvements to Victim Process Thawing and OOM
   Reaper Traversal Order" from zhongjinji makes a number of improvements
   in the OOM killer: mainly thawing a more appropriate group of victim
   threads so they can release resources.
 
 - The 5 patch series "mm/damon: misc fixups and improvements for 6.18"
   from SeongJae Park is a bunch of small and unrelated fixups for DAMON.
 
 - The 7 patch series "mm/damon: define and use DAMON initialization
   check function" from SeongJae Park implement reliability and
   maintainability improvements to a recently-added bug fix.
 
 - The 2 patch series "mm/damon/stat: expose auto-tuned intervals and
   non-idle ages" from SeongJae Park provides additional transparency to
   userspace clients of the DAMON_STAT information.
 
 - The 2 patch series "Expand scope of khugepaged anonymous collapse"
   from Dev Jain removes some constraints on khubepaged's collapsing of
   anon VMAs.  It also increases the success rate of MADV_COLLAPSE against
   an anon vma.
 
 - The 2 patch series "mm: do not assume file == vma->vm_file in
   compat_vma_mmap_prepare()" from Lorenzo Stoakes moves us further towards
   removal of file_operations.mmap().  This patchset concentrates upon
   clearing up the treatment of stacked filesystems.
 
 - The 6 patch series "mm: Improve mlock tracking for large folios" from
   Kiryl Shutsemau provides some fixes and improvements to mlock's tracking
   of large folios.  /proc/meminfo's "Mlocked" field became more accurate.
 
 - The 2 patch series "mm/ksm: Fix incorrect accounting of KSM counters
   during fork" from Donet Tom fixes several user-visible KSM stats
   inaccuracies across forks and adds selftest code to verify these
   counters.
 
 - The 2 patch series "mm_slot: fix the usage of mm_slot_entry" from Wei
   Yang addresses some potential but presently benign issues in KSM's
   mm_slot handling.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaN3cywAKCRDdBJ7gKXxA
 jtaPAQDmIuIu7+XnVUK5V11hsQ/5QtsUeLHV3OsAn4yW5/3dEQD/UddRU08ePN+1
 2VRB0EwkLAdfMWW7TfiNZ+yhuoiL/AA=
 =4mhY
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - "mm, swap: improve cluster scan strategy" from Kairui Song improves
   performance and reduces the failure rate of swap cluster allocation

 - "support large align and nid in Rust allocators" from Vitaly Wool
   permits Rust allocators to set NUMA node and large alignment when
   perforning slub and vmalloc reallocs

 - "mm/damon/vaddr: support stat-purpose DAMOS" from Yueyang Pan extend
   DAMOS_STAT's handling of the DAMON operations sets for virtual
   address spaces for ops-level DAMOS filters

 - "execute PROCMAP_QUERY ioctl under per-vma lock" from Suren
   Baghdasaryan reduces mmap_lock contention during reads of
   /proc/pid/maps

 - "mm/mincore: minor clean up for swap cache checking" from Kairui Song
   performs some cleanup in the swap code

 - "mm: vm_normal_page*() improvements" from David Hildenbrand provides
   code cleanup in the pagemap code

 - "add persistent huge zero folio support" from Pankaj Raghav provides
   a block layer speedup by optionalls making the
   huge_zero_pagepersistent, instead of releasing it when its refcount
   falls to zero

 - "kho: fixes and cleanups" from Mike Rapoport adds a few touchups to
   the recently added Kexec Handover feature

 - "mm: make mm->flags a bitmap and 64-bit on all arches" from Lorenzo
   Stoakes turns mm_struct.flags into a bitmap. To end the constant
   struggle with space shortage on 32-bit conflicting with 64-bit's
   needs

 - "mm/swapfile.c and swap.h cleanup" from Chris Li cleans up some swap
   code

 - "selftests/mm: Fix false positives and skip unsupported tests" from
   Donet Tom fixes a few things in our selftests code

 - "prctl: extend PR_SET_THP_DISABLE to only provide THPs when advised"
   from David Hildenbrand "allows individual processes to opt-out of
   THP=always into THP=madvise, without affecting other workloads on the
   system".

   It's a long story - the [1/N] changelog spells out the considerations

 - "Add and use memdesc_flags_t" from Matthew Wilcox gets us started on
   the memdesc project. Please see

      https://kernelnewbies.org/MatthewWilcox/Memdescs and
      https://blogs.oracle.com/linux/post/introducing-memdesc

 - "Tiny optimization for large read operations" from Chi Zhiling
   improves the efficiency of the pagecache read path

 - "Better split_huge_page_test result check" from Zi Yan improves our
   folio splitting selftest code

 - "test that rmap behaves as expected" from Wei Yang adds some rmap
   selftests

 - "remove write_cache_pages()" from Christoph Hellwig removes that
   function and converts its two remaining callers

 - "selftests/mm: uffd-stress fixes" from Dev Jain fixes some UFFD
   selftests issues

 - "introduce kernel file mapped folios" from Boris Burkov introduces
   the concept of "kernel file pages". Using these permits btrfs to
   account its metadata pages to the root cgroup, rather than to the
   cgroups of random inappropriate tasks

 - "mm/pageblock: improve readability of some pageblock handling" from
   Wei Yang provides some readability improvements to the page allocator
   code

 - "mm/damon: support ARM32 with LPAE" from SeongJae Park teaches DAMON
   to understand arm32 highmem

 - "tools: testing: Use existing atomic.h for vma/maple tests" from
   Brendan Jackman performs some code cleanups and deduplication under
   tools/testing/

 - "maple_tree: Fix testing for 32bit compiles" from Liam Howlett fixes
   a couple of 32-bit issues in tools/testing/radix-tree.c

 - "kasan: unify kasan_enabled() and remove arch-specific
   implementations" from Sabyrzhan Tasbolatov moves KASAN arch-specific
   initialization code into a common arch-neutral implementation

 - "mm: remove zpool" from Johannes Weiner removes zspool - an
   indirection layer which now only redirects to a single thing
   (zsmalloc)

 - "mm: task_stack: Stack handling cleanups" from Pasha Tatashin makes a
   couple of cleanups in the fork code

 - "mm: remove nth_page()" from David Hildenbrand makes rather a lot of
   adjustments at various nth_page() callsites, eventually permitting
   the removal of that undesirable helper function

 - "introduce kasan.write_only option in hw-tags" from Yeoreum Yun
   creates a KASAN read-only mode for ARM, using that architecture's
   memory tagging feature. It is felt that a read-only mode KASAN is
   suitable for use in production systems rather than debug-only

 - "mm: hugetlb: cleanup hugetlb folio allocation" from Kefeng Wang does
   some tidying in the hugetlb folio allocation code

 - "mm: establish const-correctness for pointer parameters" from Max
   Kellermann makes quite a number of the MM API functions more accurate
   about the constness of their arguments. This was getting in the way
   of subsystems (in this case CEPH) when they attempt to improving
   their own const/non-const accuracy

 - "Cleanup free_pages() misuse" from Vishal Moola fixes a number of
   code sites which were confused over when to use free_pages() vs
   __free_pages()

 - "Add Rust abstraction for Maple Trees" from Alice Ryhl makes the
   mapletree code accessible to Rust. Required by nouveau and by its
   forthcoming successor: the new Rust Nova driver

 - "selftests/mm: split_huge_page_test: split_pte_mapped_thp
   improvements" from David Hildenbrand adds a fix and some cleanups to
   the thp selftesting code

 - "mm, swap: introduce swap table as swap cache (phase I)" from Chris
   Li and Kairui Song is the first step along the path to implementing
   "swap tables" - a new approach to swap allocation and state tracking
   which is expected to yield speed and space improvements. This
   patchset itself yields a 5-20% performance benefit in some situations

 - "Some ptdesc cleanups" from Matthew Wilcox utilizes the new memdesc
   layer to clean up the ptdesc code a little

 - "Fix va_high_addr_switch.sh test failure" from Chunyu Hu fixes some
   issues in our 5-level pagetable selftesting code

 - "Minor fixes for memory allocation profiling" from Suren Baghdasaryan
   addresses a couple of minor issues in relatively new memory
   allocation profiling feature

 - "Small cleanups" from Matthew Wilcox has a few cleanups in
   preparation for more memdesc work

 - "mm/damon: add addr_unit for DAMON_LRU_SORT and DAMON_RECLAIM" from
   Quanmin Yan makes some changes to DAMON in furtherance of supporting
   arm highmem

 - "selftests/mm: Add -Wunreachable-code and fix warnings" from Muhammad
   Anjum adds that compiler check to selftests code and fixes the
   fallout, by removing dead code

 - "Improvements to Victim Process Thawing and OOM Reaper Traversal
   Order" from zhongjinji makes a number of improvements in the OOM
   killer: mainly thawing a more appropriate group of victim threads so
   they can release resources

 - "mm/damon: misc fixups and improvements for 6.18" from SeongJae Park
   is a bunch of small and unrelated fixups for DAMON

 - "mm/damon: define and use DAMON initialization check function" from
   SeongJae Park implement reliability and maintainability improvements
   to a recently-added bug fix

 - "mm/damon/stat: expose auto-tuned intervals and non-idle ages" from
   SeongJae Park provides additional transparency to userspace clients
   of the DAMON_STAT information

 - "Expand scope of khugepaged anonymous collapse" from Dev Jain removes
   some constraints on khubepaged's collapsing of anon VMAs. It also
   increases the success rate of MADV_COLLAPSE against an anon vma

 - "mm: do not assume file == vma->vm_file in compat_vma_mmap_prepare()"
   from Lorenzo Stoakes moves us further towards removal of
   file_operations.mmap(). This patchset concentrates upon clearing up
   the treatment of stacked filesystems

 - "mm: Improve mlock tracking for large folios" from Kiryl Shutsemau
   provides some fixes and improvements to mlock's tracking of large
   folios. /proc/meminfo's "Mlocked" field became more accurate

 - "mm/ksm: Fix incorrect accounting of KSM counters during fork" from
   Donet Tom fixes several user-visible KSM stats inaccuracies across
   forks and adds selftest code to verify these counters

 - "mm_slot: fix the usage of mm_slot_entry" from Wei Yang addresses
   some potential but presently benign issues in KSM's mm_slot handling

* tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (372 commits)
  mm: swap: check for stable address space before operating on the VMA
  mm: convert folio_page() back to a macro
  mm/khugepaged: use start_addr/addr for improved readability
  hugetlbfs: skip VMAs without shareable locks in hugetlb_vmdelete_list
  alloc_tag: fix boot failure due to NULL pointer dereference
  mm: silence data-race in update_hiwater_rss
  mm/memory-failure: don't select MEMORY_ISOLATION
  mm/khugepaged: remove definition of struct khugepaged_mm_slot
  mm/ksm: get mm_slot by mm_slot_entry() when slot is !NULL
  hugetlb: increase number of reserving hugepages via cmdline
  selftests/mm: add fork inheritance test for ksm_merging_pages counter
  mm/ksm: fix incorrect KSM counter handling in mm_struct during fork
  drivers/base/node: fix double free in register_one_node()
  mm: remove PMD alignment constraint in execmem_vmalloc()
  mm/memory_hotplug: fix typo 'esecially' -> 'especially'
  mm/rmap: improve mlock tracking for large folios
  mm/filemap: map entire large folio faultaround
  mm/fault: try to map the entire file folio in finish_fault()
  mm/rmap: mlock large folios in try_to_unmap_one()
  mm/rmap: fix a mlock race condition in folio_referenced_one()
  ...
2025-10-02 18:18:33 -07:00
Miaohe Lin
5ce1dbfdd8 mm/hwpoison: decouple hwpoison_filter from mm/memory-failure.c
mm/memory-failure.c defines and uses hwpoison_filter_* parameters but the
values of those parameters can only be modified via mm/hwpoison-inject.c
from userspace.  They have a potentially different life time.  Decouple
those parameters from mm/memory-failure.c to fix this broken layering.

Link: https://lkml.kernel.org/r/20250904062258.3336092-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-21 14:22:21 -07:00
Thomas Gleixner
ec45783fce memcg: optimize exit to user space
memcg uses TIF_NOTIFY_RESUME to handle reclaiming on exit to user space. 
TIF_NOTIFY_RESUME is a multiplexing TIF bit, which is utilized by other
entities as well.

This results in a unconditional mem_cgroup_handle_over_high() call for
every invocation of resume_user_mode_work(), which is a pointless exercise
as most of the time there is no reclaim work to do.

Especially since RSEQ is used by glibc, TIF_NOTIFY_RESUME is raised quite
frequently and the empty calls show up in exit path profiling.

Optimize this by doing a quick check of the reclaim condition before
invoking it.

[akpm@linux-foundation.org: remove now-unneeded test of memcg_nr_pages_over_high==0, per Shakeel]
Link: https://lkml.kernel.org/r/87tt2b6zgs.ffs@tglx
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-13 16:55:01 -07:00
Kuniyuki Iwashima
bb178c6bc0 net-memcg: Pass struct sock to mem_cgroup_sk_(un)?charge().
We will store a flag in the lowest bit of sk->sk_memcg.

Then, we cannot pass the raw pointer to mem_cgroup_charge_skmem()
and mem_cgroup_uncharge_skmem().

Let's pass struct sock to the functions.

While at it, they are renamed to match other functions starting
with mem_cgroup_sk_.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Link: https://patch.msgid.link/20250815201712.1745332-9-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-19 19:20:59 -07:00
Kuniyuki Iwashima
f7161b234f net-memcg: Introduce mem_cgroup_from_sk().
We will store a flag in the lowest bit of sk->sk_memcg.

Then, directly dereferencing sk->sk_memcg will be illegal, and we
do not want to allow touching the raw sk->sk_memcg in many places.

Let's introduce mem_cgroup_from_sk().

Other places accessing the raw sk->sk_memcg will be converted later.

Note that we cannot define the helper as an inline function in
memcontrol.h as we cannot access any fields of struct sock there
due to circular dependency, so it is placed in sock.h.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Link: https://patch.msgid.link/20250815201712.1745332-7-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-19 19:20:59 -07:00
Kuniyuki Iwashima
68889dfd54 mptcp: Fix up subflow's memcg when CONFIG_SOCK_CGROUP_DATA=n.
When sk_alloc() allocates a socket, mem_cgroup_sk_alloc() sets
sk->sk_memcg based on the current task.

MPTCP subflow socket creation is triggered from userspace or
an in-kernel worker.

In the latter case, sk->sk_memcg is not what we want.  So, we fix
it up from the parent socket's sk->sk_memcg in mptcp_attach_cgroup().

Although the code is placed under #ifdef CONFIG_MEMCG, it is buried
under #ifdef CONFIG_SOCK_CGROUP_DATA.

The two configs are orthogonal.  If CONFIG_MEMCG is enabled without
CONFIG_SOCK_CGROUP_DATA, the subflow's memory usage is not charged
correctly.

Let's move the code out of the wrong ifdef guard.

Note that sk->sk_memcg is freed in sk_prot_free() and the parent
sk holds the refcnt of memcg->css here, so we don't need to use
css_tryget().

Fixes: 3764b0c565 ("mptcp: attach subflow socket to parent cgroup")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Link: https://patch.msgid.link/20250815201712.1745332-2-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-19 19:20:58 -07:00
Linus Torvalds
6aee5aed2e cgroup: Changes for v6.17
- Allow css_rstat_updated() in NMI context to enable memory accounting for
   allocations in NMI context.
 
 - /proc/cgroups doesn't contain useful information for cgroup2 and was
   updated to only show v1 controllers. This unfortunately broke something in
   the wild. Add an option to bring back the old behavior to ease transition.
 
 - selftest updates and other cleanups.
 -----BEGIN PGP SIGNATURE-----
 
 iIQEABYKACwWIQTfIjM1kS57o3GsC/uxYfJx3gVYGQUCaIqlxQ4cdGpAa2VybmVs
 Lm9yZwAKCRCxYfJx3gVYGcTMAQDUlGf50ATWB9hDU7zUG4lVn8s8n8/+x8QFGHn4
 e4NERQD9FpU/jLN+cwGgspKo+L9qpu/1g+t36cJLcOuEKKoaQwI=
 =FLwx
 -----END PGP SIGNATURE-----

Merge tag 'cgroup-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:

 - Allow css_rstat_updated() in NMI context to enable memory accounting
   for allocations in NMI context.

 - /proc/cgroups doesn't contain useful information for cgroup2 and was
   updated to only show v1 controllers. This unfortunately broke
   something in the wild. Add an option to bring back the old behavior
   to ease transition.

 - selftest updates and other cleanups.

* tag 'cgroup-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: Add compatibility option for content of /proc/cgroups
  selftests/cgroup: fix cpu.max tests
  cgroup: llist: avoid memory tears for llist_node
  selftests: cgroup: Fix missing newline in test_zswap_writeback_one
  selftests: cgroup: Allow longer timeout for kmem_dead_cgroups cleanup
  memcg: cgroup: call css_rstat_updated irrespective of in_nmi()
  cgroup: remove per-cpu per-subsystem locks
  cgroup: make css_rstat_updated nmi safe
  cgroup: support to enable nmi-safe css_rstat_updated
  selftests: cgroup: Fix compilation on pre-cgroupns kernels
  selftests: cgroup: Optionally set up v1 environment
  selftests: cgroup: Add support for named v1 hierarchies in test_core
  selftests: cgroup_util: Add helpers for testing named v1 hierarchies
  Documentation: cgroup: add section explaining controller availability
  cgroup: Drop sock_cgroup_classid() dummy implementation
2025-07-31 16:04:19 -07:00
Kuniyuki Iwashima
378bdb9740 memcg: convert memcg->socket_pressure to u64
memcg->socket_pressure is initialised with jiffies when the memcg is
created.

Once vmpressure detects that the cgroup is under memory pressure, the
field is updated with jiffies + HZ to signal the fact to the socket layer
and suppress memory allocation for one second.

Otherwise, the field is not updated.

mem_cgroup_under_socket_pressure() uses time_before() to check if jiffies
is less than memcg->socket_pressure, and this has a bug on 32-bit kernel.

  if (time_before(jiffies, memcg->socket_pressure))
          return true;

As time_before() casts the final result to long, the acceptable delta
between two timestamps is 2 ^ (BITS_PER_LONG - 1).

On 32-bit kernel with CONFIG_HZ=1000, this is about 24 days.

  >>> (2 ** 31) / 1000 / 60 / 60 / 24
  24.855134814814818

Once 24 days have passed since the last update of socket_pressure,
mem_cgroup_under_socket_pressure() starts to lie until the next 24 days
pass.

We don't need to worry about this on 64-bit machines unless they serve for
300 million years.

  >>> (2 ** 63) / 1000 / 60 / 60 / 24 / 365
  292471208.6775361

Let's convert memcg->socket_pressure to u64.

Performance teting:

I don't have a real 32-bit machine so this is a result on QEMU, but
with/without the u64 jiffie patch, the time spent in
mem_cgroup_under_socket_pressure() was 1~5us and I didn't see any
measurable delta.

no patch applied:
iperf3   273 [000]   137.296248:
probe:mem_cgroup_under_socket_pressure: (c13660d0)
                c13660d1 mem_cgroup_under_socket_pressure+0x1
([kernel.kallsyms])
iperf3   273 [000]   137.296249:
probe:mem_cgroup_under_socket_pressure__return: (c13660d0 <- c1d8fd7f)
iperf3   273 [000]   137.296251:
probe:mem_cgroup_under_socket_pressure: (c13660d0)
                c13660d1 mem_cgroup_under_socket_pressure+0x1
([kernel.kallsyms])
iperf3   273 [000]   137.296253:
probe:mem_cgroup_under_socket_pressure__return: (c13660d0 <- c1d8fd7f)


u64 jiffies patch applied:
iperf3   308 [001]   330.669370:
probe:mem_cgroup_under_socket_pressure: (c12ddba0)
                c12ddba1 mem_cgroup_under_socket_pressure+0x1
([kernel.kallsyms])
iperf3   308 [001]   330.669371:
probe:mem_cgroup_under_socket_pressure__return: (c12ddba0 <- c1ce98bf)
iperf3   308 [001]   330.669382:
probe:mem_cgroup_under_socket_pressure: (c12ddba0)
                c12ddba1 mem_cgroup_under_socket_pressure+0x1
([kernel.kallsyms])
iperf3   308 [001]   330.669384:
probe:mem_cgroup_under_socket_pressure__return: (c12ddba0 <- c1ce98bf)

So the u64 approach is good enough.

Link: https://lkml.kernel.org/r/20250717194645.1096500-1-kuniyu@google.com
Fixes: 8e8ae64524 ("mm: memcontrol: hook up vmpressure to socket pressure")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reported-by: Neal Cardwell <ncardwell@google.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <ncardwell@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-24 19:12:32 -07:00
Davidlohr Bueso
2b7226af73 mm/memcg: make memory.reclaim interface generic
This adds a general call for both parsing as well as the common reclaim
semantics.  memcg is still the only user and no change in semantics.

[akpm@linux-foundation.org: fix CONFIG_NUMA=n build]
Link: https://lkml.kernel.org/r/20250623185851.830632-3-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-19 18:59:52 -07:00
Chen Yu
db6cc3f4ac Revert "sched/numa: add statistics of numa balance task"
This reverts commit ad6b26b6a0.

This commit introduces per-memcg/task NUMA balance statistics, but
unfortunately it introduced a NULL pointer exception due to the following
race condition: After a swap task candidate was chosen, its mm_struct
pointer was set to NULL due to task exit.  Later, when performing the
actual task swapping, the p->mm caused the problem.

CPU0                                   CPU1
:
...
task_numa_migrate
     task_numa_find_cpu
      task_numa_compare
        # a normal task p is chosen
        env->best_task = p

                                          # p exit:
                                          exit_signals(p);
                                             p->flags |= PF_EXITING
                                          exit_mm
                                             p->mm = NULL;

      migrate_swap_stop
        __migrate_swap_task((arg->src_task, arg->dst_cpu)
         count_memcg_event_mm(p->mm, NUMA_TASK_SWAP)# p->mm is NULL

task_lock() should be held and the PF_EXITING flag needs to be checked to
prevent this from happening.  After discussion, the conclusion was that
adding a lock is not worthwhile for some statistics calculations.  Revert
the change and rely on the tracepoint for this purpose.

Link: https://lkml.kernel.org/r/20250704135620.685752-1-yu.c.chen@intel.com
Link: https://lkml.kernel.org/r/20250708064917.BBD13C4CEED@smtp.kernel.org
Fixes: ad6b26b6a0 ("sched/numa: add statistics of numa balance task")
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Reported-by: Jirka Hladky <jhladky@redhat.com>
Closes: https://lore.kernel.org/all/CAE4VaGBLJxpd=NeRJXpSCuw=REhC5LWJpC29kDy-Zh2ZDyzQZA@mail.gmail.com/
Reported-by: Srikanth Aithal <Srikanth.Aithal@amd.com>
Reported-by: Suneeth D <Suneeth.D@amd.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Hladky <jhladky@redhat.com>
Cc: Libo Chen <libo.chen@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09 21:07:56 -07:00