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2335 commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Alexander Potapenko
|
d155aab90f |
mm/kfence: fix KASAN hardware tag faults during late enablement
When KASAN hardware tags are enabled, re-enabling KFENCE late (via
/sys/module/kfence/parameters/sample_interval) causes KASAN faults.
This happens because the KFENCE pool and metadata are allocated via the
page allocator, which tags the memory, while KFENCE continues to access it
using untagged pointers during initialization.
Use __GFP_SKIP_KASAN for late KFENCE pool and metadata allocations to
ensure the memory remains untagged, consistent with early allocations from
memblock. To support this, add __GFP_SKIP_KASAN to the allowlist in
__alloc_contig_verify_gfp_mask().
Link: https://lkml.kernel.org/r/20260220144940.2779209-1-glider@google.com
Fixes:
|
||
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 ... |
||
|
Linus Torvalds
|
44331bd6a6 |
Three MM hotfixes, all three are cc:stable.
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Merge tag 'mm-hotfixes-stable-2026-02-13-07-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM fixes from Andrew Morton:
"Three MM hotfixes, all three are cc:stable"
* tag 'mm-hotfixes-stable-2026-02-13-07-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
procfs: fix possible double mmput() in do_procmap_query()
mm/page_alloc: skip debug_check_no_{obj,locks}_freed with FPI_TRYLOCK
mm/hugetlb: restore failed global reservations to subpool
|
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Mikhail Gavrilov
|
ac1ea21959 |
mm/page_alloc: clear page->private in free_pages_prepare()
Several subsystems (slub, shmem, ttm, etc.) use page->private but don't
clear it before freeing pages. When these pages are later allocated as
high-order pages and split via split_page(), tail pages retain stale
page->private values.
This causes a use-after-free in the swap subsystem. The swap code uses
page->private to track swap count continuations, assuming freshly
allocated pages have page->private == 0. When stale values are present,
swap_count_continued() incorrectly assumes the continuation list is valid
and iterates over uninitialized page->lru containing LIST_POISON values,
causing a crash:
KASAN: maybe wild-memory-access in range [0xdead000000000100-0xdead000000000107]
RIP: 0010:__do_sys_swapoff+0x1151/0x1860
Fix this by clearing page->private in free_pages_prepare(), ensuring all
freed pages have clean state regardless of previous use.
Link: https://lkml.kernel.org/r/20260207173615.146159-1-mikhail.v.gavrilov@gmail.com
Fixes:
|
||
Harry Yoo
|
338ad1e84d |
mm/page_alloc: skip debug_check_no_{obj,locks}_freed with FPI_TRYLOCK
When CONFIG_DEBUG_OBJECTS_FREE is enabled,
debug_check_no_{obj,locks}_freed() functions are called.
Since both of them spin on a lock, they are not safe to be called if the
FPI_TRYLOCK flag is specified. This leads to a lockdep splat:
================================
WARNING: inconsistent lock state
6.19.0-rc5-slab-for-next+ #326 Tainted: G N
--------------------------------
inconsistent {INITIAL USE} -> {IN-NMI} usage.
kunit_try_catch/9046 [HC2[2]:SC0[0]:HE0:SE1] takes:
ffffffff84ed6bf8 (&obj_hash[i].lock){-.-.}-{2:2}, at: __debug_check_no_obj_freed+0xe0/0x300
{INITIAL USE} state was registered at:
lock_acquire+0xd9/0x2f0
_raw_spin_lock_irqsave+0x4c/0x80
__debug_object_init+0x9d/0x1f0
debug_object_init+0x34/0x50
__init_work+0x28/0x40
init_cgroup_housekeeping+0x151/0x210
init_cgroup_root+0x3d/0x140
cgroup_init_early+0x30/0x240
start_kernel+0x3e/0xcd0
x86_64_start_reservations+0x18/0x30
x86_64_start_kernel+0xf3/0x140
common_startup_64+0x13e/0x148
irq event stamp: 2998
hardirqs last enabled at (2997): [<ffffffff8298b77a>] exc_nmi+0x11a/0x240
hardirqs last disabled at (2998): [<ffffffff8298b991>] sysvec_irq_work+0x11/0x110
softirqs last enabled at (1416): [<ffffffff813c1f72>] __irq_exit_rcu+0x132/0x1c0
softirqs last disabled at (1303): [<ffffffff813c1f72>] __irq_exit_rcu+0x132/0x1c0
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&obj_hash[i].lock);
<Interrupt>
lock(&obj_hash[i].lock);
*** DEADLOCK ***
Rename free_pages_prepare() to __free_pages_prepare(), add an fpi_t
parameter, and skip those checks if FPI_TRYLOCK is set. To keep the fpi_t
definition in mm/page_alloc.c, add a wrapper function free_pages_prepare()
that always passes FPI_NONE and use it in mm/compaction.c.
Link: https://lkml.kernel.org/r/20260209062639.16577-1-harry.yoo@oracle.com
Fixes:
|
||
|
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.
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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
...
|
||
|
Linus Torvalds
|
148f95f75c |
slab updates for 7.0
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||
Kefeng Wang
|
9a8e0c31b3 |
mm: page_alloc: optimize pfn_range_valid_contig()
The alloc_contig_pages() spends a significant amount of time within
pfn_range_valid_contig().
- set_max_huge_pages
- 99.98% alloc_pool_huge_folio
only_alloc_fresh_hugetlb_folio.isra.0
- alloc_contig_frozen_pages_noprof
- 87.00% pfn_range_valid_contig
pfn_to_online_page
- 12.91% alloc_contig_frozen_range_noprof
4.51% replace_free_hugepage_folios
- 4.02% prep_new_page
prep_compound_page
- 2.98% undo_isolate_page_range
- 2.79% unset_migratetype_isolate
- 2.75% __move_freepages_block_isolate
2.71% __move_freepages_block
- 0.98% start_isolate_page_range
0.66% set_migratetype_isolate
To optimize this process, use the new helper page_is_unmovable() to avoid
more unnecessary iterations for compound pages, such as THP not on LRU,
and high-order buddy pages, which significantly improving the efficiency
of contiguous memory allocation.
A simple test on machine with 114G free memory, allocate 120 * 1G
HugeTLB folios(104 successfully returned),
time echo 120 > /sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages
Before: 0m3.605s
After: 0m0.602s
Link: https://lkml.kernel.org/r/20260112150954.1802953-3-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
||
Jiayuan Chen
|
a45088376d |
mm/vmscan: add tracepoint and reason for kswapd_failures reset
Currently, kswapd_failures is reset in multiple places (kswapd, direct reclaim, PCP freeing, memory-tiers), but there's no way to trace when and why it was reset, making it difficult to debug memory reclaim issues. This patch: 1. Introduce kswapd_clear_hopeless() as a wrapper function to centralize kswapd_failures reset logic. 2. Introduce kswapd_test_hopeless() to encapsulate hopeless node checks, replacing all open-coded kswapd_failures comparisons. 3. Add kswapd_clear_hopeless_reason enum to distinguish reset sources: - KSWAPD_CLEAR_HOPELESS_KSWAPD: reset from kswapd context - KSWAPD_CLEAR_HOPELESS_DIRECT: reset from direct reclaim - KSWAPD_CLEAR_HOPELESS_PCP: reset from PCP page freeing - KSWAPD_CLEAR_HOPELESS_OTHER: reset from other paths 4. Add tracepoints for better observability: - mm_vmscan_kswapd_clear_hopeless: traces each reset with reason - mm_vmscan_kswapd_reclaim_fail: traces each kswapd reclaim failure Test results: $ trace-cmd record -e vmscan:mm_vmscan_kswapd_clear_hopeless -e vmscan:mm_vmscan_kswapd_reclaim_fail $ # generate memory pressure $ trace-cmd report cpus=4 kswapd0-71 [000] 27.216563: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=1 kswapd0-71 [000] 27.217169: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=2 kswapd0-71 [000] 27.217764: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=3 kswapd0-71 [000] 27.218353: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=4 kswapd0-71 [000] 27.218993: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=5 kswapd0-71 [000] 27.219744: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=6 kswapd0-71 [000] 27.220488: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=7 kswapd0-71 [000] 27.221206: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=8 kswapd0-71 [000] 27.221806: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=9 kswapd0-71 [000] 27.222634: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=10 kswapd0-71 [000] 27.223286: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=11 kswapd0-71 [000] 27.223894: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=12 kswapd0-71 [000] 27.224712: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=13 kswapd0-71 [000] 27.225424: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=14 kswapd0-71 [000] 27.226082: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=15 kswapd0-71 [000] 27.226810: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=16 kswapd1-72 [002] 27.386869: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=1 kswapd1-72 [002] 27.387435: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=2 kswapd1-72 [002] 27.388016: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=3 kswapd1-72 [002] 27.388586: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=4 kswapd1-72 [002] 27.389155: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=5 kswapd1-72 [002] 27.389723: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=6 kswapd1-72 [002] 27.390292: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=7 kswapd1-72 [002] 27.392364: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=8 kswapd1-72 [002] 27.392934: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=9 kswapd1-72 [002] 27.393504: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=10 kswapd1-72 [002] 27.394073: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=11 kswapd1-72 [002] 27.394899: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=12 kswapd1-72 [002] 27.395472: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=13 kswapd1-72 [002] 27.396055: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=14 kswapd1-72 [002] 27.396628: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=15 kswapd1-72 [002] 27.397199: mm_vmscan_kswapd_reclaim_fail: nid=1 failures=16 kworker/u18:0-40 [002] 27.410151: mm_vmscan_kswapd_clear_hopeless: nid=0 reason=DIRECT kswapd0-71 [000] 27.439454: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=1 kswapd0-71 [000] 27.440048: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=2 kswapd0-71 [000] 27.440634: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=3 kswapd0-71 [000] 27.441211: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=4 kswapd0-71 [000] 27.441787: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=5 kswapd0-71 [000] 27.442363: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=6 kswapd0-71 [000] 27.443030: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=7 kswapd0-71 [000] 27.443725: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=8 kswapd0-71 [000] 27.444315: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=9 kswapd0-71 [000] 27.444898: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=10 kswapd0-71 [000] 27.445476: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=11 kswapd0-71 [000] 27.446053: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=12 kswapd0-71 [000] 27.446646: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=13 kswapd0-71 [000] 27.447230: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=14 kswapd0-71 [000] 27.447812: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=15 kswapd0-71 [000] 27.448391: mm_vmscan_kswapd_reclaim_fail: nid=0 failures=16 ann-423 [003] 28.028285: mm_vmscan_kswapd_clear_hopeless: nid=0 reason=PCP Link: https://lkml.kernel.org/r/20260120024402.387576-3-jiayuan.chen@linux.dev Signed-off-by: Jiayuan Chen <jiayuan.chen@shopee.com> Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Suggested-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> [tracing] Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: David Hildenbrand <david@kernel.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wei Xu <weixugc@google.com> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
Manish Kumar
|
d468d8f86d |
mm: drop filename from page_alloc.c header comment
The file name in the header comment is redundant and not useful, as the location is already known from the path. Remove it to align with kernel coding style. No functional change. Link: https://lkml.kernel.org/r/20260115193100.116109-1-manish1588@gmail.com Signed-off-by: Manish Kumar <manish1588@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
Vlastimil Babka
|
ab2f752ac3 |
slab: remove defer_deactivate_slab()
There are no more cpu slabs so we don't need their deferred deactivation. The function is now only used from places where we allocate a new slab but then can't spin on node list_lock to put it on the partial list. Instead of the deferred action we can free it directly via __free_slab(), we just need to tell it to use _nolock() freeing of the underlying pages and take care of the accounting. Since free_frozen_pages_nolock() variant does not yet exist for code outside of the page allocator, create it as a trivial wrapper for __free_frozen_pages(..., FPI_TRYLOCK). Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Reviewed-by: Hao Li <hao.li@linux.dev> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
|
Kefeng Wang
|
e0c1326779 |
mm: page_alloc: add alloc_contig_frozen_{range,pages}()
In order to allocate given range of pages or allocate compound pages
without incrementing their refcount, adding two new helper
alloc_contig_frozen_{range,pages}() which may be beneficial to some users
(eg hugetlb).
The new alloc_contig_{range,pages} only take !__GFP_COMP gfp now, and the
free_contig_range() is refactored to only free non-compound pages, the
only caller to free compound pages in cma_free_folio() is changed
accordingly, and the free_contig_frozen_range() is provided to match the
alloc_contig_frozen_range(), which is used to free frozen pages.
Link: https://lkml.kernel.org/r/20260109093136.1491549-5-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
||
|
Kefeng Wang
|
a9deb800b8 |
mm: page_alloc: add __split_page()
Factor out the splitting of non-compound page from make_alloc_exact() and split_page() into a new helper function __split_page(). While at it, convert the VM_BUG_ON_PAGE() into a VM_WARN_ON_PAGE(). Link: https://lkml.kernel.org/r/20260109093136.1491549-3-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Muchun Song <muchun.song@linux.dev> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> Cc: Mark Brown <broonie@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Kefeng Wang
|
01152bd2e4 |
mm: debug_vm_pgtable: add debug_vm_pgtable_free_huge_page()
Patch series "mm: hugetlb: allocate frozen gigantic folio", v6. Introduce alloc_contig_frozen_pages() and cma_alloc_frozen_compound() which avoid atomic operation about page refcount, and then convert to allocate frozen gigantic folio by the new helpers in hugetlb to cleanup the alloc_gigantic_folio(). This patch (of 6): Add a new helper to free huge page to be consistency to debug_vm_pgtable_alloc_huge_page(), and use HPAGE_PUD_ORDER instead of open-code. Also move the free_contig_range() under CONFIG_ALLOC_CONTIG since all caller are built with CONFIG_ALLOC_CONTIG. Link: https://lkml.kernel.org/r/20260109093136.1491549-2-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Muchun Song <muchun.song@linux.dev> Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> Cc: Mark Brown <broonie@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Vlastimil Babka
|
2c4c3e2989 |
mm/page_alloc: simplify __alloc_pages_slowpath() flow
The actions done before entering the main retry loop include waking up
kswapds and an allocation attempt with the precise alloc_flags. Then in
the loop we keep waking up kswapds, and we retry the allocation with flags
potentially further adjusted by being allowed to use reserves (due to e.g.
becoming an OOM killer victim).
We can adjust the retry loop to keep only one instance of waking up
kswapds and allocation attempt. Introduce the can_retry_reserves variable
for retrying once when we become eligible for reserves. It is still
useful not to evaluate reserve_flags immediately for the first allocation
attempt, because it's better to first try succeed in a non-preferred zone
above the min watermark before allocating immediately from the preferred
zone below min watermark.
Additionally move the cpuset update checks introduced by
|
||
|
Vlastimil Babka
|
53a9b4646f |
mm/page_alloc: refactor the initial compaction handling
The initial direct compaction done in some cases in __alloc_pages_slowpath() stands out from the main retry loop of reclaim + compaction. We can simplify this by instead skipping the initial reclaim attempt via a new local variable compact_first, and handle the compact_prority as necessary to match the original behavior. No functional change intended. Link: https://lkml.kernel.org/r/20260106-thp-thisnode-tweak-v3-2-f5d67c21a193@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Suggested-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Joshua Hahn <joshua.hahnjy@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: David Hildenbrand (Red Hat) <david@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Vlastimil Babka
|
6698721815 |
mm/page_alloc: ignore the exact initial compaction result
Patch series "tweaks for __alloc_pages_slowpath()", v3. This patch (of 3): For allocations that are of costly order and __GFP_NORETRY (and can perform compaction) we attempt direct compaction first. If that fails, we continue with a single round of direct reclaim+compaction (as for other __GFP_NORETRY allocations, except the compaction is of lower priority), with two exceptions that fail immediately: - __GFP_THISNODE is specified, to prevent zone_reclaim_mode-like behavior for e.g. THP page faults - compaction failed because it was deferred (i.e. has been failing recently so further attempts are not done for a while) or skipped, which means there are insufficient free base pages to defragment to begin with Upon closer inspection, the second condition has a somewhat flawed reasoning. If there are not enough base pages and reclaim could create them, we instead fail. When there are enough base pages and compaction has already ran and failed, we proceed and hope that reclaim and the subsequent compaction attempt will succeed. But it's unclear why they should and whether it will be as inexpensive as intended. It might make therefore more sense to just fail unconditionally after the initial compaction attempt. However that would change the semantics of __GFP_NORETRY to attempt reclaim at least once. Alternatively we can remove the compaction result checks and proceed with the single reclaim and (lower priority) compaction attempt, leaving only the __GFP_THISNODE exception for failing immediately. Link: https://lkml.kernel.org/r/20260106-thp-thisnode-tweak-v3-0-f5d67c21a193@suse.cz Link: https://lkml.kernel.org/r/20260106-thp-thisnode-tweak-v3-1-f5d67c21a193@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: David Hildenbrand (Red Hat) <david@kernel.org> Cc: David Rientjes <rientjes@google.com> 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: Mike Rapoport <rppt@kernel.org> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
Gregory Price
|
3bb64898f0 |
page_alloc: allow migration of smaller hugepages during contig_alloc
We presently skip regions with hugepages entirely when trying to do
contiguous page allocation. This will cause otherwise-movable 2MB HugeTLB
pages to be considered unmovable, and makes 1GB gigantic page allocation
less reliable on systems utilizing both.
Commit
|
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|
Vlastimil Babka
|
9c9828d3ea |
mm, page_alloc, thp: prevent reclaim for __GFP_THISNODE THP allocations
Since commit |
||
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> |
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|
Linus Torvalds
|
c03e9c42ae |
dma-mapping fixes for Linux 6.19
- minor fixes for the corner cases of the SWIOTLB pool management (Robin Murphy) -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQSrngzkoBtlA8uaaJ+Jp1EFxbsSRAUCaW+NbgAKCRCJp1EFxbsS RKU3AQCIpNwIYN6evmnTXO/Y+AFRjsrb1pE1cUyHn5QTY4/o4wEA6BiSgMCrZEbv HTEs1ZSHgLOwBwZre1Z11icGg3BkRgY= =6fBC -----END PGP SIGNATURE----- Merge tag 'dma-mapping-6.19-2026-01-20' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux Pull dma-mapping fixes from Marek Szyprowski: - minor fixes for the corner cases of the SWIOTLB pool management (Robin Murphy) * tag 'dma-mapping-6.19-2026-01-20' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: dma/pool: Avoid allocating redundant pools mm_zone: Generalise has_managed_dma() dma/pool: Improve pool lookup |
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|
Vlastimil Babka
|
038a102535 |
mm/page_alloc: prevent pcp corruption with SMP=n
The kernel test robot has reported: BUG: spinlock trylock failure on UP on CPU#0, kcompactd0/28 lock: 0xffff888807e35ef0, .magic: dead4ead, .owner: kcompactd0/28, .owner_cpu: 0 CPU: 0 UID: 0 PID: 28 Comm: kcompactd0 Not tainted 6.18.0-rc5-00127-ga06157804399 #1 PREEMPT 8cc09ef94dcec767faa911515ce9e609c45db470 Call Trace: <IRQ> __dump_stack (lib/dump_stack.c:95) dump_stack_lvl (lib/dump_stack.c:123) dump_stack (lib/dump_stack.c:130) spin_dump (kernel/locking/spinlock_debug.c:71) do_raw_spin_trylock (kernel/locking/spinlock_debug.c:?) _raw_spin_trylock (include/linux/spinlock_api_smp.h:89 kernel/locking/spinlock.c:138) __free_frozen_pages (mm/page_alloc.c:2973) ___free_pages (mm/page_alloc.c:5295) __free_pages (mm/page_alloc.c:5334) tlb_remove_table_rcu (include/linux/mm.h:? include/linux/mm.h:3122 include/asm-generic/tlb.h:220 mm/mmu_gather.c:227 mm/mmu_gather.c:290) ? __cfi_tlb_remove_table_rcu (mm/mmu_gather.c:289) ? rcu_core (kernel/rcu/tree.c:?) rcu_core (include/linux/rcupdate.h:341 kernel/rcu/tree.c:2607 kernel/rcu/tree.c:2861) rcu_core_si (kernel/rcu/tree.c:2879) handle_softirqs (arch/x86/include/asm/jump_label.h:36 include/trace/events/irq.h:142 kernel/softirq.c:623) __irq_exit_rcu (arch/x86/include/asm/jump_label.h:36 kernel/softirq.c:725) irq_exit_rcu (kernel/softirq.c:741) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1052) </IRQ> <TASK> RIP: 0010:_raw_spin_unlock_irqrestore (arch/x86/include/asm/preempt.h:95 include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) free_pcppages_bulk (mm/page_alloc.c:1494) drain_pages_zone (include/linux/spinlock.h:391 mm/page_alloc.c:2632) __drain_all_pages (mm/page_alloc.c:2731) drain_all_pages (mm/page_alloc.c:2747) kcompactd (mm/compaction.c:3115) kthread (kernel/kthread.c:465) ? __cfi_kcompactd (mm/compaction.c:3166) ? __cfi_kthread (kernel/kthread.c:412) ret_from_fork (arch/x86/kernel/process.c:164) ? __cfi_kthread (kernel/kthread.c:412) ret_from_fork_asm (arch/x86/entry/entry_64.S:255) </TASK> Matthew has analyzed the report and identified that in drain_page_zone() we are in a section protected by spin_lock(&pcp->lock) and then get an interrupt that attempts spin_trylock() on the same lock. The code is designed to work this way without disabling IRQs and occasionally fail the trylock with a fallback. However, the SMP=n spinlock implementation assumes spin_trylock() will always succeed, and thus it's normally a no-op. Here the enabled lock debugging catches the problem, but otherwise it could cause a corruption of the pcp structure. The problem has been introduced by commit |
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Aboorva Devarajan
|
b9efe36b5e |
mm/page_alloc: make percpu_pagelist_high_fraction reads lock-free
When page isolation loops indefinitely during memory offline, reading /proc/sys/vm/percpu_pagelist_high_fraction blocks on pcp_batch_high_lock, causing hung task warnings. Make procfs reads lock-free since percpu_pagelist_high_fraction is a simple integer with naturally atomic reads, writers still serialize via the mutex. This prevents hung task warnings when reading the procfs file during long-running memory offline operations. [akpm@linux-foundation.org: add comment, per Michal] Link: https://lkml.kernel.org/r/aS_y9AuJQFydLEXo@tiehlicka Link: https://lkml.kernel.org/r/20251201060009.1420792-1-aboorvad@linux.ibm.com Signed-off-by: Aboorva Devarajan <aboorvad@linux.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
Robin Murphy
|
6626734dd2 |
mm_zone: Generalise has_managed_dma()
It would be useful to be able to check for potential DMA pages beyond just ZONE_DMA - generalise the existing has_managed_dma() function to allow checking other zones too. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Tested-by: Vladimir Kondratiev <vladimir.kondratiev@mobileye.com> Reviewed-by: Baoquan He <bhe@redhat.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/r/bd002d2351074e57be1ca08f03f333debac658fb.1768230104.git.robin.murphy@arm.com |
||
Joshua Hahn
|
0c75714095 |
mm/page_alloc: report 1 as zone_batchsize for !CONFIG_MMU
Commit |
||
Alexander Gordeev
|
7838a4eb8a |
mm/page_alloc: change all pageblocks migrate type on coalescing
When a page is freed it coalesces with a buddy into a higher order page
while possible. When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.
However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.
That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.
[ 308.986589] ------------[ cut here ]------------
[ 308.987227] page type is 0, passed migratetype is 1 (nr=256)
[ 308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[ 308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[ 308.987439] Unloaded tainted modules: hmac_s390(E):2
[ 308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G E 6.18.0-gcc-bpf-debug #431 PREEMPT
[ 308.987657] Tainted: [E]=UNSIGNED_MODULE
[ 308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[ 308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[ 308.987676] R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[ 308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[ 308.987688] 0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[ 308.987692] 0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[ 308.987696] 0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[ 308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2 larl %r2,000003499883abd4
00000349976fa5f6: c0e5ffe3f4b5 brasl %r14,0000034997378f60
#00000349976fa5fc: af000000 mc 0,0
>00000349976fa600: a7f4ff4c brc 15,00000349976fa498
00000349976fa604: b9040026 lgr %r2,%r6
00000349976fa608: c0300088317f larl %r3,0000034998800906
00000349976fa60e: c0e5fffdb6e1 brasl %r14,00000349976b13d0
00000349976fa614: af000000 mc 0,0
[ 308.987734] Call Trace:
[ 308.987738] [<00000349976fa600>] expand+0x240/0x270
[ 308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[ 308.987749] [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[ 308.987754] [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[ 308.987759] [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[ 308.987763] [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[ 308.987768] [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[ 308.987774] [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[ 308.987781] [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[ 308.987786] [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[ 308.987791] [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[ 308.987799] [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[ 308.987804] [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[ 308.987809] [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[ 308.987813] [<000003499734d70e>] do_exception+0x1de/0x540
[ 308.987822] [<0000034998387390>] __do_pgm_check+0x130/0x220
[ 308.987830] [<000003499839a934>] pgm_check_handler+0x114/0x160
[ 308.987838] 3 locks held by mempig_verify/5224:
[ 308.987842] #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[ 308.987859] #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[ 308.987871] #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[ 308.987886] Last Breaking-Event-Address:
[ 308.987890] [<0000034997379096>] __warn_printk+0x136/0x140
[ 308.987897] irq event stamp: 52330356
[ 308.987901] hardirqs last enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[ 308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[ 308.987913] softirqs last enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[ 308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[ 308.987929] ---[ end trace 0000000000000000 ]---
[ 308.987936] ------------[ cut here ]------------
[ 308.987940] page type is 0, passed migratetype is 1 (nr=256)
[ 308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[ 308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[ 308.988070] Unloaded tainted modules: hmac_s390(E):2
[ 308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G W E 6.18.0-gcc-bpf-debug #431 PREEMPT
[ 308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[ 308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[ 308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[ 308.988118] R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[ 308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[ 308.988133] 0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[ 308.988139] 0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[ 308.988144] 0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[ 308.988153] Krnl Code: 00000349976f9e22: c020008a06d9 larl %r2,000003499883abd4
00000349976f9e28: c0e5ffe3f89c brasl %r14,0000034997378f60
#00000349976f9e2e: af000000 mc 0,0
>00000349976f9e32: a7f4ff4e brc 15,00000349976f9cce
00000349976f9e36: b904002b lgr %r2,%r11
00000349976f9e3a: c030008a06e7 larl %r3,000003499883ac08
00000349976f9e40: c0e5fffdbac8 brasl %r14,00000349976b13d0
00000349976f9e46: af000000 mc 0,0
[ 308.988184] Call Trace:
[ 308.988188] [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[ 308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[ 308.988202] [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[ 308.988208] [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[ 308.988214] [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[ 308.988221] [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[ 308.988227] [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[ 308.988233] [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[ 308.988240] [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[ 308.988247] [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[ 308.988253] [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[ 308.988260] [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[ 308.988267] [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[ 308.988273] [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[ 308.988279] [<000003499734d70e>] do_exception+0x1de/0x540
[ 308.988286] [<0000034998387390>] __do_pgm_check+0x130/0x220
[ 308.988293] [<000003499839a934>] pgm_check_handler+0x114/0x160
[ 308.988300] 3 locks held by mempig_verify/5224:
[ 308.988305] #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[ 308.988322] #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[ 308.988334] #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[ 308.988346] Last Breaking-Event-Address:
[ 308.988350] [<0000034997379096>] __warn_printk+0x136/0x140
[ 308.988356] irq event stamp: 52330356
[ 308.988360] hardirqs last enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[ 308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[ 308.988373] softirqs last enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[ 308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[ 308.988388] ---[ end trace 0000000000000000 ]---
Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes:
|
||
|
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.
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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
|
||
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Linus Torvalds
|
b687034b1a |
slab updates for 6.19
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Merge tag 'slab-for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab updates from Vlastimil Babka:
- mempool_alloc_bulk() support for upcoming users in the block layer
that need to allocate multiple objects at once with the mempool's
guaranteed progress semantics, which is not achievable with an
allocation single objects in a loop. Along with refactoring and
various improvements (Christoph Hellwig)
- Preparations for the upcoming separation of struct slab from struct
page, mostly by removing the struct folio layer, as the purpose of
struct folio has shifted since it became used in slab code (Matthew
Wilcox)
- Modernisation of slab's boot param API usage, which removes some
unexpected parsing corner cases (Petr Tesarik)
- Refactoring of freelist_aba_t (now struct freelist_counters) and
associated functions for double cmpxchg, enabled by -fms-extensions
(Vlastimil Babka)
- Cleanups and improvements related to sheaves caching layer, that were
part of the full conversion to sheaves, which is planned for the next
release (Vlastimil Babka)
* tag 'slab-for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: (42 commits)
slab: Remove unnecessary call to compound_head() in alloc_from_pcs()
mempool: clarify behavior of mempool_alloc_preallocated()
mempool: drop the file name in the top of file comment
mempool: de-typedef
mempool: remove mempool_{init,create}_kvmalloc_pool
mempool: legitimize the io_schedule_timeout in mempool_alloc_from_pool
mempool: add mempool_{alloc,free}_bulk
mempool: factor out a mempool_alloc_from_pool helper
slab: Remove references to folios from virt_to_slab()
kasan: Remove references to folio in __kasan_mempool_poison_object()
memcg: Convert mem_cgroup_from_obj_folio() to mem_cgroup_from_obj_slab()
mempool: factor out a mempool_adjust_gfp helper
mempool: add error injection support
mempool: improve kerneldoc comments
mm: improve kerneldoc comments for __alloc_pages_bulk
fault-inject: make enum fault_flags available unconditionally
usercopy: Remove folio references from check_heap_object()
slab: Remove folio references from kfree_nolock()
slab: Remove folio references from kfree_rcu_sheaf()
slab: Remove folio references from build_detached_freelist()
...
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fujunjie
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a493c7a650 |
mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity
calculate_totalreserve_pages() currently finds the maximum lowmem_reserve[j] for a zone by scanning the full forward range [j = zone_idx .. MAX_NR_ZONES). However, for a given zone i, the lowmem_reserve[j] array (for j > i) is naturally expected to form a monotonically non-decreasing sequence in j, not as an implementation detail, but as a consequence that naturally arises from the semantics of lowmem_reserve[]. For zone "i", lowmem_reserve[j] expresses how many pages in zone i must effectively be kept in reserve when deciding whether an allocation class that may allocate from zones up to j is allowed to fall back into i. It protects less flexible allocation classes (which cannot use higher zones) from being starved by more flexible ones. Viewed from this semantics, it is natural to expect a partial ordering in j: as j increases, the allocation class gains access to a strictly larger set of fallback zones. Therefore lowmem_reserve[j] is expected to be monotonically non-decreasing in j: more flexible allocation classes must not be allowed to deplete low zones more aggressively than less flexible ones. In other words, if lowmem_reserve[j] were ever observed to *decrease* as j grows, that would be unexpected from the reserve semantics' point of view and would likely indicate a semantic change or a misconfiguration. The current implementation in setup_per_zone_lowmem_reserve() reflects this policy by accumulating managed pages from higher zones and applying the configured ratio, which results in a non-decreasing sequence. This patch makes calculate_totalreserve_pages() rely on that monotonicity explicitly and finds the maximum reserve value by scanning backward and stopping at the first non-zero entry. This avoids unnecessary iteration and reflects the conceptual model more directly. No functional behavior changes. To maintain this assumption explicitly, a comment is added next to setup_per_zone_lowmem_reserve() documenting the monotonicity expectation and noting that calculate_totalreserve_pages() relies on it. Link: https://lkml.kernel.org/r/tencent_EB0FED91B01B1F8B6DAEE96719C5F5797F07@qq.com Signed-off-by: fujunjie <fujunjie1@qq.com> Acked-by: Zi Yan <ziy@nvidia.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
Shakeel Butt
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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> |
||
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Linus Torvalds
|
5bebe8de19 |
mm/huge_memory: Fix initialization of huge zero folio
The recent fix to properly initialize the tags of the huge zero folio
had an unfortunate not-so-subtle side effect: it caused the actual
*contents* of the huge zero folio to not be initialized at all when the
hardware didn't support the memory tagging.
The reason was the unfortunate semantics of tag_clear_highpage(): on
hardware that didn't do the tagging, it would silently just not do
anything at all. And since this is done only on arm64 with MTE support,
that basically meant most hardware.
It wasn't necessarily immediately obvious since the huge zero page isn't
necessarily very heavily used - or because it might already be zero
because all-zeroes is the most common pattern. But it ends up causing
random odd user space failures when you do hit it.
The unfortunate semantics have been around for a while, but became a
real bug only when we started actively using __GFP_ZEROTAGS in the
generic get_huge_zero_folio() function - before that, it had only ever
been used in code that checked that the hardware supported it.
Fix this by simply changing the semantics of tag_clear_highpage() to
return whether it actually successfully did something or not. While at
it, also make it initialize multiple pages in one go, since that's
actually what the only caller wants it to do and it simplifies the whole
logic.
Fixes:
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Baokun Li
|
ee040cbd6e |
mm/page_alloc: don't warn about large allocations with __GFP_NOFAIL
Filesystems use __GFP_NOFAIL to allocate block-sized folios for metadata reads at critical points, since they cannot afford to go read-only, shut down, or enter an inconsistent state due to memory pressure. Currently, attempting to allocate page units greater than order-1 with the __GFP_NOFAIL flag triggers a WARN_ON() in __alloc_pages_slowpath(). However, filesystems supporting large block sizes (blocksize > PAGE_SIZE) can easily require allocations larger than order-1. As Matthew Wilcox noted in [1], if we have a filesystem with 64KiB sectors, there will be many clean folios in the page cache that are 64KiB or larger. He also explained in [2] why kvmalloc isn't a valid approach here. With gfp flags and order already included in the OOM report, both Vlastimil Babka and Michal Hocko suggested that we can take the risk of removing this warning first and then observe whether a large number of related OOM reports appear. If that happens, we can consider adding special handling in other places. Link: https://lkml.kernel.org/r/20251105085652.4081123-1-libaokun@huaweicloud.com Signed-off-by: Baokun Li <libaokun1@huawei.com> Suggested-by: Matthew Wilcox <willy@infradead.org> Link: https://lore.kernel.org/all/aQPX1-XWQjKaMTZB@casper.infradead.org [1] Link: https://lore.kernel.org/all/aQTHMI3t5mNXp0M1@casper.infradead.org [2] Suggested-by: Vlastimil Babka <vbabka@suse.cz> Link: https://lore.kernel.org/all/188a95ba-6384-4319-bb74-c0d9ec6c4079@suse.cz Suggested-by: Michal Hocko <mhocko@suse.com> Link: https://lore.kernel.org/all/aQotQBjnDDeL_wHx@tiehlicka Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Brendan Jackman <jackmanb@google.com> Cc: ErKun Yang <yangerkun@huawei.com> Cc: Jan Kara <jack@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: "zhangyi (F)" <yi.zhang@huawei.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
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Vlastimil Babka
|
0f21b91101 |
mm/page_alloc: simplify and cleanup pcp locking
The pcp locking relies on pcp_spin_trylock() which has to be used together with pcp_trylock_prepare()/pcp_trylock_finish() to work properly on !SMP !RT configs. This is tedious and error-prone. We can remove pcp_spin_lock() and underlying pcpu_spin_lock() because we don't use it. Afterwards pcp_spin_unlock() is only used together with pcp_spin_trylock(). Therefore we can add the UP_flags parameter to them both and handle pcp_trylock_prepare()/finish() within. Additionally for the configs where pcp_trylock_prepare()/finish() are no-op (SMP || RT) make them pass &UP_flags to a no-op inline function. This ensures typechecking and makes the local variable "used" so we can remove the __maybe_unused attributes. In my compile testing, bloat-o-meter reported no change on SMP config, so the compiler is capable of optimizing away the no-ops same as before, and we have simplified the code using pcp_spin_trylock(). Link: https://lkml.kernel.org/r/20251015-b4-pcp-lock-cleanup-v2-1-740d999595d5@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Joshua Hahn <joshua.hahnjy@gmail.com> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
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Joshua Hahn
|
91e6912966 |
mm/page_alloc: batch page freeing in free_frozen_page_commit
Before returning, free_frozen_page_commit calls free_pcppages_bulk using nr_pcp_free to determine how many pages can appropritately be freed, based on the tunable parameters stored in pcp. While this number is an accurate representation of how many pages should be freed in total, it is not an appropriate number of pages to free at once using free_pcppages_bulk, since we have seen the value consistently go above 2000 in the Meta fleet on larger machines. As such, perform batched page freeing in free_pcppages_bulk by using pcp->batch. In order to ensure that other processes are not starved of the zone lock, free both the zone lock and pcp lock to yield to other threads. Note that because free_frozen_page_commit now performs a spinlock inside the function (and can fail), the function may now return with a freed pcp. To handle this, return true if the pcp is locked on exit and false otherwise. In addition, since free_frozen_page_commit must now be aware of what UP flags were stored at the time of the spin lock, and because we must be able to report new UP flags to the callers, add a new unsigned long* parameter UP_flags to keep track of this. The following are a few synthetic benchmarks, made on three machines. The first is a large machine with 754GiB memory and 316 processors. The second is a relatively smaller machine with 251GiB memory and 176 processors. The third and final is the smallest of the three, which has 62GiB memory and 36 processors. On all machines, I kick off a kernel build with -j$(nproc). Negative delta is better (faster compilation) Large machine (754GiB memory, 316 processors) make -j$(nproc) +------------+---------------+-----------+ | Metric (s) | Variation (%) | Delta(%) | +------------+---------------+-----------+ | real | 0.8070 | - 1.4865 | | user | 0.2823 | + 0.4081 | | sys | 5.0267 | -11.8737 | +------------+---------------+-----------+ Medium machine (251GiB memory, 176 processors) make -j$(nproc) +------------+---------------+----------+ | Metric (s) | Variation (%) | Delta(%) | +------------+---------------+----------+ | real | 0.2806 | +0.0351 | | user | 0.0994 | +0.3170 | | sys | 0.6229 | -0.6277 | +------------+---------------+----------+ Small machine (62GiB memory, 36 processors) make -j$(nproc) +------------+---------------+----------+ | Metric (s) | Variation (%) | Delta(%) | +------------+---------------+----------+ | real | 0.1503 | -2.6585 | | user | 0.0431 | -2.2984 | | sys | 0.1870 | -3.2013 | +------------+---------------+----------+ Here, variation is the coefficient of variation, i.e. standard deviation / mean. [joshua.hahnjy@gmail.com: simplify checks] Link: https://lkml.kernel.org/r/20251014192827.851389-1-joshua.hahnjy@gmail.com Link: https://lkml.kernel.org/r/20251014145011.3427205-4-joshua.hahnjy@gmail.com Signed-off-by: Joshua Hahn <joshua.hahnjy@gmail.com> Suggested-by: Chris Mason <clm@fb.com> Co-developed-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Brendan Jackman <jackmanb@google.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Michal Hocko <mhocko@suse.com> Cc: SeongJae Park <sj@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
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Joshua Hahn
|
fc4b909c36 |
mm/page_alloc: batch page freeing in decay_pcp_high
It is possible for pcp->count - pcp->high to exceed pcp->batch by a lot. When this happens, we should perform batching to ensure that free_pcppages_bulk isn't called with too many pages to free at once and starve out other threads that need the pcp or zone lock. Since we are still only freeing the difference between the initial pcp->count and pcp->high values, there should be no change to how many pages are freed. Link: https://lkml.kernel.org/r/20251014145011.3427205-3-joshua.hahnjy@gmail.com Signed-off-by: Joshua Hahn <joshua.hahnjy@gmail.com> Suggested-by: Chris Mason <clm@fb.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Co-developed-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Brendan Jackman <jackmanb@google.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Michal Hocko <mhocko@suse.com> Cc: SeongJae Park <sj@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
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Joshua Hahn
|
0acc67c403 |
mm/page_alloc/vmstat: simplify refresh_cpu_vm_stats change detection
Patch series "mm/page_alloc: Batch callers of free_pcppages_bulk", v5. Motivation & Approach ===================== While testing workloads with high sustained memory pressure on large machines in the Meta fleet (1Tb memory, 316 CPUs), we saw an unexpectedly high number of softlockups. Further investigation showed that the zone lock in free_pcppages_bulk was being held for a long time, and was called to free 2k+ pages over 100 times just during boot. This causes starvation in other processes for the zone lock, which can lead to the system stalling as multiple threads cannot make progress without the locks. We can see these issues manifesting as warnings: [ 4512.591979] rcu: INFO: rcu_sched self-detected stall on CPU [ 4512.604370] rcu: 20-....: (9312 ticks this GP) idle=a654/1/0x4000000000000000 softirq=309340/309344 fqs=5426 [ 4512.626401] rcu: hardirqs softirqs csw/system [ 4512.638793] rcu: number: 0 145 0 [ 4512.651177] rcu: cputime: 30 10410 174 ==> 10558(ms) [ 4512.666657] rcu: (t=21077 jiffies g=783665 q=1242213 ncpus=316) While these warnings don't indicate a crash or a kernel panic, they do point to the underlying issue of lock contention. To prevent starvation in both locks, batch the freeing of pages using pcp->batch. Because free_pcppages_bulk is called with the pcp lock and acquires the zone lock, relinquishing and reacquiring the locks are only effective when both of them are broken together (unless the system was built with queued spinlocks). Thus, instead of modifying free_pcppages_bulk to break both locks, batch the freeing from its callers instead. A similar fix has been implemented in the Meta fleet, and we have seen significantly less softlockups. Testing ======= The following are a few synthetic benchmarks, made on three machines. The first is a large machine with 754GiB memory and 316 processors. The second is a relatively smaller machine with 251GiB memory and 176 processors. The third and final is the smallest of the three, which has 62GiB memory and 36 processors. On all machines, I kick off a kernel build with -j$(nproc). Negative delta is better (faster compilation). Large machine (754GiB memory, 316 processors) make -j$(nproc) +------------+---------------+-----------+ | Metric (s) | Variation (%) | Delta(%) | +------------+---------------+-----------+ | real | 0.8070 | - 1.4865 | | user | 0.2823 | + 0.4081 | | sys | 5.0267 | -11.8737 | +------------+---------------+-----------+ Medium machine (251GiB memory, 176 processors) make -j$(nproc) +------------+---------------+----------+ | Metric (s) | Variation (%) | Delta(%) | +------------+---------------+----------+ | real | 0.2806 | +0.0351 | | user | 0.0994 | +0.3170 | | sys | 0.6229 | -0.6277 | +------------+---------------+----------+ Small machine (62GiB memory, 36 processors) make -j$(nproc) +------------+---------------+----------+ | Metric (s) | Variation (%) | Delta(%) | +------------+---------------+----------+ | real | 0.1503 | -2.6585 | | user | 0.0431 | -2.2984 | | sys | 0.1870 | -3.2013 | +------------+---------------+----------+ Here, variation is the coefficient of variation, i.e. standard deviation / mean. Based on these results, it seems like there are varying degrees to how much lock contention this reduces. For the largest and smallest machines that I ran the tests on, it seems like there is quite some significant reduction. There is also some performance increases visible from userspace. Interestingly, the performance gains don't scale with the size of the machine, but rather there seems to be a dip in the gain there is for the medium-sized machine. One possible theory is that because the high watermark depends on both memory and the number of local CPUs, what impacts zone contention the most is not these individual values, but rather the ratio of mem:processors. This patch (of 5): Currently, refresh_cpu_vm_stats returns an int, indicating how many changes were made during its updates. Using this information, callers like vmstat_update can heuristically determine if more work will be done in the future. However, all of refresh_cpu_vm_stats's callers either (a) ignore the result, only caring about performing the updates, or (b) only care about whether changes were made, but not *how many* changes were made. Simplify the code by returning a bool instead to indicate if updates were made. In addition, simplify fold_diff and decay_pcp_high to return a bool for the same reason. Link: https://lkml.kernel.org/r/20251014145011.3427205-1-joshua.hahnjy@gmail.com Link: https://lkml.kernel.org/r/20251014145011.3427205-2-joshua.hahnjy@gmail.com Signed-off-by: Joshua Hahn <joshua.hahnjy@gmail.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: SeongJae Park <sj@kernel.org> Cc: Brendan Jackman <jackmanb@google.com> Cc: Chris Mason <clm@fb.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Michal Hocko <mhocko@suse.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Joshua Hahn
|
2783088ef2 |
mm/page_alloc: prevent reporting pcp->batch = 0
zone_batchsize returns the appropriate value that should be used for pcp->batch. If it finds a zone with less than 4096 pages or PAGE_SIZE > 1M, however, it leads to some incorrect math. In the above case, we will get an intermediary value of 1, which is then rounded down to the nearest power of two, and 1 is subtracted from it. Since 1 is already a power of two, we will get batch = 1-1 = 0: batch = rounddown_pow_of_two(batch + batch/2) - 1; A pcp->batch value of 0 is nonsensical. If this were actually set, then functions like drain_zone_pages would become no-ops, since they could only free 0 pages at a time. Of the two callers of zone_batchsize, the one that is actually used to set pcp->batch works around this by setting pcp->batch to the maximum of 1 and zone_batchsize. However, the other caller, zone_pcp_init, incorrectly prints out the batch size of the zone to be 0. This is probably rare in a typical zone, but the DMA zone can often have less than 4096 pages, which means it will print out "LIFO batch:0". Before: [ 0.001216] DMA zone: 3998 pages, LIFO batch:0 After: [ 0.001210] DMA zone: 3998 pages, LIFO batch:1 Instead of dealing with the error handling and the mismatch between the reported and actual zone batchsize, just return 1 if the zone_batchsize is 1 page or less before the rounding. Link: https://lkml.kernel.org/r/20251009192933.3756712-3-joshua.hahnjy@gmail.com Signed-off-by: Joshua Hahn <joshua.hahnjy@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Brendan Jackman <jackmanb@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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|
Joshua Hahn
|
4dcf65bf5b |
mm/page_alloc: clarify batch tuning in zone_batchsize
Patch series "mm/page_alloc: pcp->batch cleanups", v2. Two small cleanups for mm/page_alloc. Patch 1 cleans up a misleading comment about how pcp->batch is calculated, and folds in the calculation to increase clarity. No functional change intended. Patch 2 corrects zones from reporting that their pcp->batch is 0 when it is actually 1. Namely, corrects ZONE_DMA from reporting that its batch size is 0. This patch (of 2): Recently while working on another patch about batching free_pcppages_bulk [1], I was curious why pcp->batch was always 63 on my machine. This led me to zone_batchsize(), where I found this set of lines to determine what the batch size should be for the host: batch = min(zone_managed_pages(zone) >> 10, SZ_1M / PAGE_SIZE); batch /= 4; /* We effectively *= 4 below */ if (batch < 1) batch = 1; All of this is good, except the comment above which says "We effectively *= 4 below". Nowhere else in the function zone_batchsize(), is there a corresponding multipliation by 4. Looking into the history of this, it seems like Dave Hansen had also noticed this back in 2013 [1]. Turns out there *used* to be a corresponding *= 4, which was turned into a *= 6 later on to be used in pageset_setup_from_batch_size(), which no longer exists. Despite this mismatch not being corrected in the comments, it seems that getting rid of the /= 4 leads to a performance regression on machines with less than 250G memory and 176 processors. As such, let us preserve the functionality but clean up the comments. Fold the /= 4 into the calculation above: bitshift by 10+2=12, and instead of dividing 1MB, divide 256KB and adjust the comments accordingly. No functional change intended. Link: https://lkml.kernel.org/r/20251009192933.3756712-1-joshua.hahnjy@gmail.com Link: https://lkml.kernel.org/r/20251009192933.3756712-2-joshua.hahnjy@gmail.com Link: https://lore.kernel.org/all/20251002204636.4016712-1-joshua.hahnjy@gmail.com/ [1] Signed-off-by: Joshua Hahn <joshua.hahnjy@gmail.com> Suggested-by: Dave Hansen <dave.hansen@intel.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Brendan Jackman <jackmanb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Christoph Hellwig
|
e9939cebc0 |
mm: improve kerneldoc comments for __alloc_pages_bulk
Describe the semantincs in more detail, as the filling empty slots in an array scheme is not quite obvious. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20251113084022.1255121-3-hch@lst.de Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
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|
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() ... |
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Alexei Starovoitov
|
d7242af864 |
mm: Introduce alloc_frozen_pages_nolock()
Split alloc_pages_nolock() and introduce alloc_frozen_pages_nolock() to be used by alloc_slab_page(). Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
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Alexei Starovoitov
|
99253de51f |
mm: Allow GFP_ACCOUNT to be used in alloc_pages_nolock().
Change alloc_pages_nolock() to default to __GFP_COMP when allocating pages, since upcoming reentrant alloc_slab_page() needs __GFP_COMP. Also allow __GFP_ACCOUNT flag to be specified, since most of BPF infra needs __GFP_ACCOUNT except BPF streams. Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
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Johannes Weiner
|
19c5fb83f2 |
mm: page_alloc: avoid kswapd thrashing due to NUMA restrictions
On NUMA systems without bindings, allocations check all nodes for free space, then wake up the kswapds on all nodes and retry. This ensures all available space is evenly used before reclaim begins. However, when one process or certain allocations have node restrictions, they can cause kswapds on only a subset of nodes to be woken up. Since kswapd hysteresis targets watermarks that are *higher* than needed for allocation, even *unrestricted* allocations can now get suckered onto such nodes that are already pressured. This ends up concentrating all allocations on them, even when there are idle nodes available for the unrestricted requests. This was observed with two numa nodes, where node0 is normal and node1 is ZONE_MOVABLE to facilitate hotplugging: a kernel allocation wakes kswapd on node0 only (since node1 is not eligible); once kswapd0 is active, the watermarks hover between low and high, and then even the movable allocations end up on node0, only to be kicked out again; meanwhile node1 is empty and idle. Similar behavior is possible when a process with NUMA bindings is causing selective kswapd wakeups. To fix this, on NUMA systems augment the (misleading) watermark test with a check for whether kswapd is already active during the first iteration through the zonelist. If this fails to place the request, kswapd must be running everywhere already, and the watermark test is good enough to decide placement. With this patch, unrestricted requests successfully make use of node1, even while kswapd is reclaiming node0 for restricted allocations. [gourry@gourry.net: don't retry if no kswapds were active] Link: https://lkml.kernel.org/r/20250919162134.1098208-1-hannes@cmpxchg.org Signed-off-by: Gregory Price <gourry@gourry.net> Tested-by: Joshua Hahn <joshua.hahnjy@gmail.com> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Zi Yan <ziy@nvidia.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Matthew Wilcox (Oracle)
|
9d003dec97 |
mm: remove page->order
We already use page->private for storing the order of a page while it's in the buddy allocator system; extend that to also storing the order while it's in the pcp_llist. Link: https://lkml.kernel.org/r/20250910142923.2465470-4-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Suren Baghdasaryan
|
7ffc923e25 |
alloc_tag: avoid warnings when freeing non-compound "tail" pages
When freeing "tail" pages of a non-compount high-order page, we properly subtract the allocation tag counters, however later when these pages are released, alloc_tag_sub() will issue warnings because tags for these pages are NULL. This issue was originally anticipated by Vlastimil in his review [1] and then recently reported by David. Prevent warnings by marking the tags empty. Link: https://lkml.kernel.org/r/20250915212756.3998938-4-surenb@google.com Link: https://lore.kernel.org/all/6db0f0c8-81cb-4d04-9560-ba73d63db4b8@suse.cz/ [1] Signed-off-by: Suren Baghdasaryan <surenb@google.com> Suggested-by: David Wang <00107082@163.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Usama Arif <usamaarif642@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Sourav Panda <souravpanda@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Chanwon Park
|
e7a5f249e6 |
mm: re-enable kswapd when memory pressure subsides or demotion is toggled
If kswapd fails to reclaim pages from a node MAX_RECLAIM_RETRIES in a
row, kswapd on that node gets disabled. That is, the system won't wakeup
kswapd for that node until page reclamation is observed at least once.
That reclamation is mostly done by direct reclaim, which in turn enables
kswapd back.
However, on systems with CXL memory nodes, workloads with high anon page
usage can disable kswapd indefinitely, without triggering direct
reclaim. This can be reproduced with following steps:
numa node 0 (32GB memory, 48 CPUs)
numa node 2~5 (512GB CXL memory, 128GB each)
(numa node 1 is disabled)
swap space 8GB
1) Set /sys/kernel/mm/demotion_enabled to 0.
2) Set /proc/sys/kernel/numa_balancing to 0.
3) Run a process that allocates and random accesses 500GB of anon
pages.
4) Let the process exit normally.
During 3), free memory on node 0 gets lower than low watermark, and
kswapd runs and depletes swap space. Then, kswapd fails consecutively
and gets disabled. Allocation afterwards happens on CXL memory, so node
0 never gains more memory pressure to trigger direct reclaim.
After 4), kswapd on node 0 remains disabled, and tasks running on that
node are unable to swap. If you turn on NUMA_BALANCING_MEMORY_TIERING
and demotion now, it won't work properly since kswapd is disabled.
To mitigate this problem, reset kswapd_failures to 0 on following
conditions:
a) ZONE_BELOW_HIGH bit of a zone in hopeless node with a fallback
memory node gets cleared.
b) demotion_enabled is changed from false to true.
Rationale for a):
ZONE_BELOW_HIGH bit being cleared might be a sign that the node may
be reclaimable afterwards. This won't help much if the memory-hungry
process keeps running without freeing anything, but at least the node
will go back to reclaimable state when the process exits.
Rationale for b):
When demotion_enabled is false, kswapd can only reclaim anon pages by
swapping them out to swap space. If demotion_enabled is turned on,
kswapd can demote anon pages to another node for reclaiming. So, the
original failure count for determining reclaimability is no longer
valid.
Since kswapd_failures resets may be missed by ++ operation, it is
changed from int to atomic_t.
[akpm@linux-foundation.org: tweak whitespace]
Link: https://lkml.kernel.org/r/aL6qGi69jWXfPc4D@pcw-MS-7D22
Signed-off-by: Chanwon Park <flyinrm@gmail.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
||
Wei Yang
|
4805ef3707 |
mm/page_alloc: check the correct buddy if it is a starting block
find_large_buddy() search buddy based on start_pfn, which maybe different
from page's pfn, e.g. when page is not pageblock aligned, because
prep_move_freepages_block() always align start_pfn to pageblock.
This means when we found a starting block at start_pfn, it may check on
the wrong page theoretically. And not split the free page as it is
supposed to, causing a freelist migratetype mismatch.
The good news is the page passed to __move_freepages_block_isolate() has
only two possible cases:
* page is pageblock aligned
* page is __first_valid_page() of this block
So it is safe for the first case, and it won't get a buddy larger than
pageblock for the second case.
To fix the issue, check the returned pfn of find_large_buddy() to decide
whether to split the free page:
1. if it is not a PageBuddy pfn, no split;
2. if it is a PageBuddy pfn but order <= pageblock_order, no split;
3. if it is a PageBuddy pfn with order > pageblock_order, start_pfn is
either in the starting block or tail block, split the PageBuddy at
pageblock_order level.
Link: https://lkml.kernel.org/r/20250905140358.28849-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
||
Vishal Moola (Oracle)
|
162f6c69ea |
mm/page_alloc: add kernel-docs for free_pages()
Patch series "Cleanup free_pages() misuse", v3. free_pages() is supposed to be called when we only have a virtual address. __free_pages() is supposed to be called when we have a page. There are a number of callers that use page_address() to get a page's virtual address then call free_pages() on it when they should just call __free_pages() directly. Add kernel-docs for free_pages() to help callers better understand which function they should be calling, and replace the obvious cases of misuse. This patch (of 7): Add kernel-docs to free_pages(). This will help callers understand when to use it instead of __free_pages(). Link: https://lkml.kernel.org/r/20250903185921.1785167-1-vishal.moola@gmail.com Link: https://lkml.kernel.org/r/20250903185921.1785167-2-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: SeongJae Park <sj@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Andy Lutomirski <luto@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Justin Sanders <justin@coraid.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Will Deacon <will@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
David Hildenbrand
|
0bf2edf041 |
mm/page_alloc: reject unreasonable folio/compound page sizes in alloc_contig_range_noprof()
Let's reject them early, which in turn makes folio_alloc_gigantic() reject them properly. To avoid converting from order to nr_pages, let's just add MAX_FOLIO_ORDER and calculate MAX_FOLIO_NR_PAGES based on that. While at it, let's just make the order a "const unsigned order". Link: https://lkml.kernel.org/r/20250901150359.867252-7-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Acked-by: SeongJae Park <sj@kernel.org> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Wei Yang
|
204dfefe03 |
mm/page_alloc: find_large_buddy() from start_pfn aligned order
We iterate pfn from order 0 to MAX_PAGE_ORDER aligned to find large buddy. While if the order is less than start_pfn aligned order, we would get the same pfn and do the same check again. Iterate from start_pfn aligned order to reduce duplicated work. [richard.weiyang@gmail.com: add comment on assignment of order] Link: https://lkml.kernel.org/r/20250828091618.7869-1-richard.weiyang@gmail.com Link: https://lkml.kernel.org/r/20250902025807.11467-1-richard.weiyang@gmail.com Link: https://lkml.kernel.org/r/20250828091618.7869-1-richard.weiyang@gmail.com Link: https://lkml.kernel.org/r/20250902025807.11467-1-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |