mirror of https://github.com/torvalds/linux.git
1042 Commits
| Author | SHA1 | Message | Date |
|---|---|---|---|
Linus Torvalds
|
7cd122b552 |
Some filesystems use a kinda-sorta controlled dentry refcount leak to pin
dentries of created objects in dcache (and undo it when removing those).
Reference is grabbed and not released, but it's not actually _stored_
anywhere. That works, but it's hard to follow and verify; among other
things, we have no way to tell _which_ of the increments is intended
to be an unpaired one. Worse, on removal we need to decide whether
the reference had already been dropped, which can be non-trivial if
that removal is on umount and we need to figure out if this dentry is
pinned due to e.g. unlink() not done. Usually that is handled by using
kill_litter_super() as ->kill_sb(), but there are open-coded special
cases of the same (consider e.g. /proc/self).
Things get simpler if we introduce a new dentry flag (DCACHE_PERSISTENT)
marking those "leaked" dentries. Having it set claims responsibility
for +1 in refcount.
The end result this series is aiming for:
* get these unbalanced dget() and dput() replaced with new primitives that
would, in addition to adjusting refcount, set and clear persistency flag.
* instead of having kill_litter_super() mess with removing the remaining
"leaked" references (e.g. for all tmpfs files that hadn't been removed
prior to umount), have the regular shrink_dcache_for_umount() strip
DCACHE_PERSISTENT of all dentries, dropping the corresponding
reference if it had been set. After that kill_litter_super() becomes
an equivalent of kill_anon_super().
Doing that in a single step is not feasible - it would affect too many places
in too many filesystems. It has to be split into a series.
This work has really started early in 2024; quite a few preliminary pieces
have already gone into mainline. This chunk is finally getting to the
meat of that stuff - infrastructure and most of the conversions to it.
Some pieces are still sitting in the local branches, but the bulk of
that stuff is here.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull persistent dentry infrastructure and conversion from Al Viro:
"Some filesystems use a kinda-sorta controlled dentry refcount leak to
pin dentries of created objects in dcache (and undo it when removing
those). A reference is grabbed and not released, but it's not actually
_stored_ anywhere.
That works, but it's hard to follow and verify; among other things, we
have no way to tell _which_ of the increments is intended to be an
unpaired one. Worse, on removal we need to decide whether the
reference had already been dropped, which can be non-trivial if that
removal is on umount and we need to figure out if this dentry is
pinned due to e.g. unlink() not done. Usually that is handled by using
kill_litter_super() as ->kill_sb(), but there are open-coded special
cases of the same (consider e.g. /proc/self).
Things get simpler if we introduce a new dentry flag
(DCACHE_PERSISTENT) marking those "leaked" dentries. Having it set
claims responsibility for +1 in refcount.
The end result this series is aiming for:
- get these unbalanced dget() and dput() replaced with new primitives
that would, in addition to adjusting refcount, set and clear
persistency flag.
- instead of having kill_litter_super() mess with removing the
remaining "leaked" references (e.g. for all tmpfs files that hadn't
been removed prior to umount), have the regular
shrink_dcache_for_umount() strip DCACHE_PERSISTENT of all dentries,
dropping the corresponding reference if it had been set. After that
kill_litter_super() becomes an equivalent of kill_anon_super().
Doing that in a single step is not feasible - it would affect too many
places in too many filesystems. It has to be split into a series.
This work has really started early in 2024; quite a few preliminary
pieces have already gone into mainline. This chunk is finally getting
to the meat of that stuff - infrastructure and most of the conversions
to it.
Some pieces are still sitting in the local branches, but the bulk of
that stuff is here"
* tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
d_make_discardable(): warn if given a non-persistent dentry
kill securityfs_recursive_remove()
convert securityfs
get rid of kill_litter_super()
convert rust_binderfs
convert nfsctl
convert rpc_pipefs
convert hypfs
hypfs: swich hypfs_create_u64() to returning int
hypfs: switch hypfs_create_str() to returning int
hypfs: don't pin dentries twice
convert gadgetfs
gadgetfs: switch to simple_remove_by_name()
convert functionfs
functionfs: switch to simple_remove_by_name()
functionfs: fix the open/removal races
functionfs: need to cancel ->reset_work in ->kill_sb()
functionfs: don't bother with ffs->ref in ffs_data_{opened,closed}()
functionfs: don't abuse ffs_data_closed() on fs shutdown
convert selinuxfs
...
|
|
|
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
|
|
|
Linus Torvalds
|
f2e74ecfba |
vfs-6.19-rc1.folio
-----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaSmOZQAKCRCRxhvAZXjc onGBAQDtqeO0jZzS7q9UxlJ84Wj/H9w+9INpO4jMxtWK4svhUAEAghG4qVxRvkE2 Qh+wrpTPIC7OCQ78k8psDRmkj9cn8QA= =FCVN -----END PGP SIGNATURE----- Merge tag 'vfs-6.19-rc1.folio' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull folio updates from Christian Brauner: "Add a new folio_next_pos() helper function that returns the file position of the first byte after the current folio. This is a common operation in filesystems when needing to know the end of the current folio. The helper is lifted from btrfs which already had its own version, and is now used across multiple filesystems and subsystems: - btrfs - buffer - ext4 - f2fs - gfs2 - iomap - netfs - xfs - mm This fixes a long-standing bug in ocfs2 on 32-bit systems with files larger than 2GiB. Presumably this is not a common configuration, but the fix is backported anyway. The other filesystems did not have bugs, they were just mildly inefficient. This also introduce uoff_t as the unsigned version of loff_t. A recent commit inadvertently changed a comparison from being unsigned (on 64-bit systems) to being signed (which it had always been on 32-bit systems), leading to sporadic fstests failures. Generally file sizes are restricted to being a signed integer, but in places where -1 is passed to indicate "up to the end of the file", it is convenient to have an unsigned type to ensure comparisons are always unsigned regardless of architecture" * tag 'vfs-6.19-rc1.folio' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: Add uoff_t mm: Use folio_next_pos() xfs: Use folio_next_pos() netfs: Use folio_next_pos() iomap: Use folio_next_pos() gfs2: Use folio_next_pos() f2fs: Use folio_next_pos() ext4: Use folio_next_pos() buffer: Use folio_next_pos() btrfs: Use folio_next_pos() filemap: Add folio_next_pos() |
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Matthew Wilcox (Oracle)
|
37d369fa97
|
fs: Add uoff_t
In a recent commit, I inadvertently changed a comparison from being an unsigned comparison (on 64-bit systems) to being a signed comparison (which it had always been on 32-bit systems). This led to a sporadic fstests failure. To make sure this comparison is always unsigned, introduce a new type, uoff_t which is the unsigned version of loff_t. Generally file sizes are restricted to being a signed integer, but in these two places it is convenient to pass -1 to indicate "up to the end of the file". Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://patch.msgid.link/20251123220518.1447261-1-willy@infradead.org Signed-off-by: Christian Brauner <brauner@kernel.org> |
|
Shakeel Butt
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c1bd09994c |
memcg: remove __lruvec_stat_mod_folio
__lruvec_stat_mod_folio() is already safe against irqs, so there is no need to have a separate interface (i.e. lruvec_stat_mod_folio) which wraps calls to it with irq disabling and reenabling. Let's rename __lruvec_stat_mod_folio() to lruvec_stat_mod_folio(). Link: https://lkml.kernel.org/r/20251110232008.1352063-5-shakeel.butt@linux.dev Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
|
Baolin Wang
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8826f09616 |
mm: shmem: allow fallback to smaller large orders for tmpfs mmap() access
After commit
|
|
Lorenzo Stoakes
|
68aa2fdbf5 |
mm: introduce leaf entry type and use to simplify leaf entry logic
The kernel maintains leaf page table entries which contain either:
The kernel maintains leaf page table entries which contain either:
- Nothing ('none' entries)
- Present entries*
- Everything else that will cause a fault which the kernel handles
* Present entries are either entries the hardware can navigate without page
fault or special cases like NUMA hint protnone or PMD with cleared
present bit which contain hardware-valid entries modulo the present bit.
In the 'everything else' group we include swap entries, but we also
include a number of other things such as migration entries, device private
entries and marker entries.
Unfortunately this 'everything else' group expresses everything through a
swp_entry_t type, and these entries are referred to swap entries even
though they may well not contain a... swap entry.
This is compounded by the rather mind-boggling concept of a non-swap swap
entry (checked via non_swap_entry()) and the means by which we twist and
turn to satisfy this.
This patch lays the foundation for reducing this confusion.
We refer to 'everything else' as a 'software-define leaf entry' or
'softleaf'. for short And in fact we scoop up the 'none' entries into
this concept also so we are left with:
- Present entries.
- Softleaf entries (which may be empty).
This allows for radical simplification across the board - one can simply
convert any leaf page table entry to a leaf entry via softleaf_from_pte().
If the entry is present, we return an empty leaf entry, so it is assumed
the caller is aware that they must differentiate between the two
categories of page table entries, checking for the former via
pte_present().
As a result, we can eliminate a number of places where we would otherwise
need to use predicates to see if we can proceed with leaf page table entry
conversion and instead just go ahead and do it unconditionally.
We do so where we can, adjusting surrounding logic as necessary to
integrate the new softleaf_t logic as far as seems reasonable at this
stage.
We typedef swp_entry_t to softleaf_t for the time being until the
conversion can be complete, meaning everything remains compatible
regardless of which type is used. We will eventually remove swp_entry_t
when the conversion is complete.
We introduce a new header file to keep things clear - leafops.h - this
imports swapops.h so can direct replace swapops imports without issue, and
we do so in all the files that require it.
Additionally, add new leafops.h file to core mm maintainers entry.
Link: https://lkml.kernel.org/r/c879383aac77d96a03e4d38f7daba893cd35fc76.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Wei Xu <weixugc@google.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Linus Torvalds
|
e7c375b181 |
vfs-6.18-rc7.fixes
-----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaRtBJwAKCRCRxhvAZXjc ou5CAQCJb5y2ULKklblICU1wR7Nr15WvTW7VVOcv44RJ22S3NgEAy4DLDBFBw8zC 8e7Hp8gxbjsq8ZJmU088aobFcqbZOwk= =TAnu -----END PGP SIGNATURE----- Merge tag 'vfs-6.18-rc7.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs Pull vfs fixes from Christian Brauner: - Fix unitialized variable in statmount_string() - Fix hostfs mounting when passing host root during boot - Fix dynamic lookup to fail on cell lookup failure - Fix missing file type when reading bfs inodes from disk - Enforce checking of sb_min_blocksize() calls and update all callers accordingly - Restore write access before closing files opened by open_exec() in binfmt_misc - Always freeze efivarfs during suspend/hibernate cycles - Fix statmount()'s and listmount()'s grab_requested_mnt_ns() helper to actually allow mount namespace file descriptor in addition to mount namespace ids - Fix tmpfs remount when noswap is specified - Switch Landlock to iput_not_last() to remove false-positives from might_sleep() annotations in iput() - Remove dead node_to_mnt_ns() code - Ensure that per-queue kobjects are successfully created * tag 'vfs-6.18-rc7.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: landlock: fix splats from iput() after it started calling might_sleep() fs: add iput_not_last() shmem: fix tmpfs reconfiguration (remount) when noswap is set fs/namespace: correctly handle errors returned by grab_requested_mnt_ns power: always freeze efivarfs binfmt_misc: restore write access before closing files opened by open_exec() block: add __must_check attribute to sb_min_blocksize() virtio-fs: fix incorrect check for fsvq->kobj xfs: check the return value of sb_min_blocksize() in xfs_fs_fill_super isofs: check the return value of sb_min_blocksize() in isofs_fill_super exfat: check return value of sb_min_blocksize in exfat_read_boot_sector vfat: fix missing sb_min_blocksize() return value checks mnt: Remove dead code which might prevent from building bfs: Reconstruct file type when loading from disk afs: Fix dynamic lookup to fail on cell lookup failure hostfs: Fix only passing host root in boot stage with new mount fs: Fix uninitialized 'offp' in statmount_string() |
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Dmitry Ilvokhin
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e97d7c5165 |
mm: shmem/tmpfs hugepage defaults config choice
Allow to override defaults for shemem and tmpfs at config time. This is consistent with how transparent hugepages can be configured. Same results can be achieved with the existing 'transparent_hugepage_shmem' and 'transparent_hugepage_tmpfs' settings in the kernel command line, but it is more convenient to define basic settings at config time instead of changing kernel command line later. Defaults for shmem and tmpfs were not changed. They are remained the same as before: 'never' for both cases. Options 'deny' and 'force' are omitted intentionally since these are special values and supposed to be used for emergencies or testing and are not expected to be permanent ones. Primary motivation for adding config option is to enable policy enforcement at build time. In large-scale production environments (Meta's for example), the kernel configuration is often maintained centrally close to the kernel code itself and owned by the kernel engineers, while boot parameters are managed independently (e.g. by provisioning systems). In such setups, the kernel build defines the supported and expected behavior in a single place, but there is no reliable or uniform control over the kernel command line options. A build-time default allows kernel integrators to enforce a predictable hugepage policy for shmem/tmpfs on a base layer, ensuring reproducible behavior and avoiding configuration drift caused by possible boot-time differences. In short, primary benefit is mostly operational: it provides a way to codify preferred policy in the kernel configuration, which is versioned, reviewed, and tested as part of the kernel build process, rather than depending on potentially variable boot parameters. [d@ilvokhin.com: v2] Link: https://lkml.kernel.org/r/aQECPpjd-fU_TC79@shell.ilvokhin.com Link: https://lkml.kernel.org/r/aPpv8sAa2sYgNu3L@shell.ilvokhin.com Signed-off-by: Dmitry Ilvokhin <d@ilvokhin.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Acked-by: Kiryl Shutsemau <kas@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mike Rapoport <rppt@kernel.org> 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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Kairui Song
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a983471cfc |
mm, swap: cleanup swap entry allocation parameter
We no longer need this GFP parameter after commit
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Lorenzo Stoakes
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89646d9c74 |
mm: add shmem_zero_setup_desc()
Add the ability to set up a shared anonymous mapping based on a VMA descriptor rather than a VMA. This is a prerequisite for converting to the char mm driver to use the mmap_prepare hook. Link: https://lkml.kernel.org/r/d9181517a7e3d6b014a5697c6990d3722c2c9fcd.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Lorenzo Stoakes
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ab3c8e7b86 |
mm/shmem: update shmem to use mmap_prepare
Patch series "expand mmap_prepare functionality, port more users", v5.
Since commit
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Ryan Roberts
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9ac09bb9fe |
mm: consistently use current->mm in mm_get_unmapped_area()
mm_get_unmapped_area() is a wrapper around arch_get_unmapped_area() / arch_get_unmapped_area_topdown(), both of which search current->mm for some free space. Neither take an mm_struct - they implicitly operate on current->mm. But the wrapper takes an mm_struct and uses it to decide whether to search bottom up or top down. All callers pass in current->mm for this, so everything is working consistently. But it feels like an accident waiting to happen; eventually someone will call that function with a different mm, expecting to find free space in it, but what gets returned is free space in the current mm. So let's simplify by removing the parameter and have the wrapper use current->mm to decide which end to start at. Now everything is consistent and self-documenting. Link: https://lkml.kernel.org/r/20251003155306.2147572-1-ryan.roberts@arm.com Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Dev Jain <dev.jain@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> 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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Al Viro
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2313598222 |
convert ramfs and tmpfs
Quite a bit is already done by infrastructure changes (simple_link(),
simple_unlink()) - all that is left is replacing d_instantiate() +
pinning dget() (in ->symlink() and ->mknod()) with d_make_persistent(),
and, in case of shmem, using simple_unlink() and simple_link() in
->unlink() and ->link() resp., instead of open-coding those there.
Since d_make_persistent() accepts (and hashes) unhashed ones, shmem
situation gets simpler - we no longer care whether ->lookup() has hashed
the sucker.
With that done, we don't need kill_litter_super() for these filesystems
anymore - by the umount time all remaining dentries will be marked
persistent and kill_litter_super() will boil down to call of
kill_anon_super().
The same goes for devtmpfs and rootfs - they are handled by
ramfs or by shmem, depending upon config.
NB: strictly speaking, both devtmpfs and rootfs ought to use
ramfs_kill_sb() if they end up using ramfs; that's a separate
story and the only impact of "just use kill_{litter,anon}_super()"
is that we fail to free their sb->s_fs_info... on reboot.
That's orthogonal to the changes in this series - kill_litter_super()
is identical to kill_anon_super() for those at this point.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Mike Yuan
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3cd1548a27
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shmem: fix tmpfs reconfiguration (remount) when noswap is set
In systemd we're trying to switch the internal credentials setup logic
to new mount API [1], and I noticed fsconfig(FSCONFIG_CMD_RECONFIGURE)
consistently fails on tmpfs with noswap option. This can be trivially
reproduced with the following:
```
int fs_fd = fsopen("tmpfs", 0);
fsconfig(fs_fd, FSCONFIG_SET_FLAG, "noswap", NULL, 0);
fsconfig(fs_fd, FSCONFIG_CMD_CREATE, NULL, NULL, 0);
fsmount(fs_fd, 0, 0);
fsconfig(fs_fd, FSCONFIG_CMD_RECONFIGURE, NULL, NULL, 0); <------ EINVAL
```
After some digging the culprit is shmem_reconfigure() rejecting
!(ctx->seen & SHMEM_SEEN_NOSWAP) && sbinfo->noswap, which is bogus
as ctx->seen serves as a mask for whether certain options are touched
at all. On top of that, noswap option doesn't use fsparam_flag_no,
hence it's not really possible to "reenable" swap to begin with.
Drop the check and redundant SHMEM_SEEN_NOSWAP flag.
[1] https://github.com/systemd/systemd/pull/39637
Fixes:
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Kairui Song
|
fc745ff317 |
mm/shmem: fix THP allocation and fallback loop
The order check and fallback loop is updating the index value on every
loop. This will cause the index to be wrongly aligned by a larger value
while the loop shrinks the order.
This may result in inserting and returning a folio of the wrong index and
cause data corruption with some userspace workloads [1].
[kasong@tencent.com: introduce a temporary variable to improve code]
Link: https://lkml.kernel.org/r/20251023065913.36925-1-ryncsn@gmail.com
Link: https://lore.kernel.org/linux-mm/CAMgjq7DqgAmj25nDUwwu1U2cSGSn8n4-Hqpgottedy0S6YYeUw@mail.gmail.com/ [1]
Link: https://lkml.kernel.org/r/20251022105719.18321-1-ryncsn@gmail.com
Link: https://lore.kernel.org/linux-mm/CAMgjq7DqgAmj25nDUwwu1U2cSGSn8n4-Hqpgottedy0S6YYeUw@mail.gmail.com/ [1]
Fixes:
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Matthew Wilcox (Oracle)
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60a70e6143
|
mm: Use folio_next_pos()
This is one instruction more efficient than open-coding folio_pos() + folio_size(). It's the equivalent of (x + y) << z rather than x << z + y << z. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://patch.msgid.link/20251024170822.1427218-11-willy@infradead.org Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Hugh Dickins <hughd@google.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-mm@kvack.org Signed-off-by: Christian Brauner <brauner@kernel.org> |
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Linus Torvalds
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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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Jackie Liu
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5919f12821 |
mm/shmem: remove unused entry_order after large swapin rework
After commit
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Kairui Song
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8578e0c00d |
mm, swap: use the swap table for the swap cache and switch API
Introduce basic swap table infrastructures, which are now just a fixed-sized flat array inside each swap cluster, with access wrappers. Each cluster contains a swap table of 512 entries. Each table entry is an opaque atomic long. It could be in 3 types: a shadow type (XA_VALUE), a folio type (pointer), or NULL. In this first step, it only supports storing a folio or shadow, and it is a drop-in replacement for the current swap cache. Convert all swap cache users to use the new sets of APIs. Chris Li has been suggesting using a new infrastructure for swap cache for better performance, and that idea combined well with the swap table as the new backing structure. Now the lock contention range is reduced to 2M clusters, which is much smaller than the 64M address_space. And we can also drop the multiple address_space design. All the internal works are done with swap_cache_get_* helpers. Swap cache lookup is still lock-less like before, and the helper's contexts are same with original swap cache helpers. They still require a pin on the swap device to prevent the backing data from being freed. Swap cache updates are now protected by the swap cluster lock instead of the XArray lock. This is mostly handled internally, but new __swap_cache_* helpers require the caller to lock the cluster. So, a few new cluster access and locking helpers are also introduced. A fully cluster-based unified swap table can be implemented on top of this to take care of all count tracking and synchronization work, with dynamic allocation. It should reduce the memory usage while making the performance even better. Link: https://lkml.kernel.org/r/20250916160100.31545-12-ryncsn@gmail.com Co-developed-by: Chris Li <chrisl@kernel.org> Signed-off-by: Chris Li <chrisl@kernel.org> Signed-off-by: Kairui Song <kasong@tencent.com> Acked-by: Chris Li <chrisl@kernel.org> Suggested-by: Chris Li <chrisl@kernel.org> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: kernel test robot <oliver.sang@intel.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Zi Yan <ziy@nvidia.com> Cc: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Kairui Song
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094dc8b059 |
mm, swap: wrap swap cache replacement with a helper
There are currently three swap cache users that are trying to replace an existing folio with a new one: huge memory splitting, migration, and shmem replacement. What they are doing is quite similar. Introduce a common helper for this. In later commits, this can be easily switched to use the swap table by updating this helper. The newly added helper also makes the swap cache API better defined, and make debugging easier by adding a few more debug checks. Migration and shmem replace are meant to clone the folio, including content, swap entry value, and flags. And splitting will adjust each sub folio's swap entry according to order, which could be non-uniform in the future. So document it clearly that it's the caller's responsibility to set up the new folio's swap entries and flags before calling the helper. The helper will just follow the new folio's entry value. This also prepares for replacing high-order folios in the swap cache. Currently, only splitting to order 0 is allowed for swap cache folios. Using the new helper, we can handle high-order folio splitting better. Link: https://lkml.kernel.org/r/20250916160100.31545-11-ryncsn@gmail.com Signed-off-by: Kairui Song <kasong@tencent.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Chris Li <chrisl@kernel.org> Suggested-by: Chris Li <chrisl@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: kernel test robot <oliver.sang@intel.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Zi Yan <ziy@nvidia.com> Cc: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Kairui Song
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84a7a9823e |
mm/shmem, swap: remove redundant error handling for replacing folio
Shmem may replace a folio in the swap cache if the cached one doesn't fit the swapin's GFP zone. When doing so, shmem has already double checked that the swap cache folio is locked, still has the swap cache flag set, and contains the wanted swap entry. So it is impossible to fail due to an XArray mismatch. There is even a comment for that. Delete the defensive error handling path, and add a WARN_ON instead: if that happened, something has broken the basic principle of how the swap cache works, we should catch and fix that. Link: https://lkml.kernel.org/r/20250916160100.31545-10-ryncsn@gmail.com Signed-off-by: Kairui Song <kasong@tencent.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Suggested-by: Chris Li <chrisl@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: kernel test robot <oliver.sang@intel.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Zi Yan <ziy@nvidia.com> Cc: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Kairui Song
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fd8d4f862f |
mm, swap: cleanup swap cache API and add kerneldoc
In preparation for replacing the swap cache backend with the swap table, clean up and add proper kernel doc for all swap cache APIs. Now all swap cache APIs are well-defined with consistent names. No feature change, only renaming and documenting. Link: https://lkml.kernel.org/r/20250916160100.31545-9-ryncsn@gmail.com Signed-off-by: Kairui Song <kasong@tencent.com> Acked-by: Chris Li <chrisl@kernel.org> Reviewed-by: Barry Song <baohua@kernel.org> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Acked-by: David Hildenbrand <david@redhat.com> Suggested-by: Chris Li <chrisl@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: kernel test robot <oliver.sang@intel.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Zi Yan <ziy@nvidia.com> Cc: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Kairui Song
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f28124617f |
mm, swap: use unified helper for swap cache look up
The swap cache lookup helper swap_cache_get_folio currently does readahead updates as well, so callers that are not doing swapin from any VMA or mapping are forced to reuse filemap helpers instead, and have to access the swap cache space directly. So decouple readahead update with swap cache lookup. Move the readahead update part into a standalone helper. Let the caller call the readahead update helper if they do readahead. And convert all swap cache lookups to use swap_cache_get_folio. After this commit, there are only three special cases for accessing swap cache space now: huge memory splitting, migration, and shmem replacing, because they need to lock the XArray. The following commits will wrap their accesses to the swap cache too, with special helpers. And worth noting, currently dropbehind is not supported for anon folio, and we will never see a dropbehind folio in swap cache. The unified helper can be updated later to handle that. While at it, add proper kernedoc for touched helpers. No functional change. Link: https://lkml.kernel.org/r/20250916160100.31545-3-ryncsn@gmail.com Signed-off-by: Kairui Song <kasong@tencent.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Barry Song <baohua@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Chris Li <chrisl@kernel.org> Acked-by: Nhat Pham <nphamcs@gmail.com> Suggested-by: Chris Li <chrisl@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: kernel test robot <oliver.sang@intel.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Zi Yan <ziy@nvidia.com> Cc: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Baolin Wang
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69e0a3b490 |
mm: shmem: fix the strategy for the tmpfs 'huge=' options
After commit |
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Max Kellermann
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8eccb066f2 |
mm: constify shmem related test functions for improved const-correctness
Patch series "mm: establish const-correctness for pointer parameters", v6. This series is to improved const-correctness in the low-level memory-management subsystem, which provides a basis for further constification further up the call stack (e.g. filesystems). I started this work when I tried to constify the Ceph filesystem code, but found that to be impossible because many "mm" functions accept non-const pointers, even though they modify nothing. This patch (of 12): We select certain test functions which either invoke each other, functions that are already const-ified, or no further functions. It is therefore relatively trivial to const-ify them, which provides a basis for further const-ification further up the call stack. Link: https://lkml.kernel.org/r/20250901205021.3573313-1-max.kellermann@ionos.com Link: https://lkml.kernel.org/r/20250901205021.3573313-2-max.kellermann@ionos.com Signed-off-by: Max Kellermann <max.kellermann@ionos.com> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Borislav Betkov <bp@alien8.de> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Christian Zankel <chris@zankel.net> Cc: David Rientjes <rientjes@google.com> Cc: David S. Miller <davem@davemloft.net> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Bottomley <james.bottomley@HansenPartnership.com> Cc: Jan Kara <jack@suse.cz> Cc: Jocelyn Falempe <jfalempe@redhat.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mark Brown <broonie@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: "Nysal Jan K.A" <nysal@linux.ibm.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russel King <linux@armlinux.org.uk> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Huth <thuth@redhat.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Wei Xu <weixugc@google.com> Cc: Yuanchu Xie <yuanchu@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Mateusz Guzik
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f99b391778
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fs: rename generic_delete_inode() and generic_drop_inode()
generic_delete_inode() is rather misleading for what the routine is doing. inode_just_drop() should be much clearer. The new naming is inconsistent with generic_drop_inode(), so rename that one as well with inode_ as the suffix. No functional changes. Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> |
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Baolin Wang
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6d11dec130 |
mm: shmem: drop the unnecessary folio_nr_pages()
We've got the number of pages in the folio earlier, thus remove the redundant folio_nr_pages() call. Link: https://lkml.kernel.org/r/67c80182ebd949e3894908e01e224697c143aabb.1756200587.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Baolin Wang
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ab1c34c834 |
mm: shmem: use 'folio' for shmem_partial_swap_usage()
It is more straightforward to use the term `folio'. No functional changes. Link: https://lkml.kernel.org/r/a2d39608d99cba1130cacd9cffbafc6949193c08.1756200587.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Baokun Li
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63ec0c26b6 |
tmpfs: preserve SB_I_VERSION on remount
Now tmpfs enables i_version by default and tmpfs does not modify it. But
SB_I_VERSION can also be modified via sb_flags, and reconfigure_super()
always overwrites the existing flags with the latest ones. This means
that if tmpfs is remounted without specifying iversion, the default
i_version will be unexpectedly disabled.
To ensure iversion remains enabled, SB_I_VERSION is now always set for
fc->sb_flags in shmem_init_fs_context(), instead of for sb->s_flags in
shmem_fill_super().
Link: https://lkml.kernel.org/r/20250819061803.1496443-1-libaokun@huaweicloud.com
Fixes:
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|
David Hildenbrand
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8cdc4d2701 |
mm/huge_memory: respect MADV_COLLAPSE with PR_THP_DISABLE_EXCEPT_ADVISED
Let's allow for making MADV_COLLAPSE succeed on areas that neither have VM_HUGEPAGE nor VM_NOHUGEPAGE when we have THP disabled unless explicitly advised (PR_THP_DISABLE_EXCEPT_ADVISED). MADV_COLLAPSE is a clear advice that we want to collapse. Note that we still respect the VM_NOHUGEPAGE flag, just like MADV_COLLAPSE always does. So consequently, MADV_COLLAPSE is now only refused on VM_NOHUGEPAGE with PR_THP_DISABLE_EXCEPT_ADVISED, including for shmem. Link: https://lkml.kernel.org/r/20250815135549.130506-4-usamaarif642@gmail.com Co-developed-by: Usama Arif <usamaarif642@gmail.com> Signed-off-by: Usama Arif <usamaarif642@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Barry Song <baohua@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jann Horn <jannh@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mariano Pache <npache@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Rik van Riel <riel@surriel.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: SeongJae Park <sj@kernel.org> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yafang <laoar.shao@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Linus Torvalds
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da23ea194d |
Significant patch series in this pull request:
- The 4 patch series "mseal cleanups" from Lorenzo Stoakes erforms some
mseal cleaning with no intended functional change.
- The 3 patch series "Optimizations for khugepaged" from David
Hildenbrand improves khugepaged throughput by batching PTE operations
for large folios. This gain is mainly for arm64.
- The 8 patch series "x86: enable EXECMEM_ROX_CACHE for ftrace and
kprobes" from Mike Rapoport provides a bugfix, additional debug code and
cleanups to the execmem code.
- The 7 patch series "mm/shmem, swap: bugfix and improvement of mTHP
swap in" from Kairui Song provides bugfixes, cleanups and performance
improvememnts to the mTHP swapin code.
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Merge tag 'mm-stable-2025-08-03-12-35' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull more MM updates from Andrew Morton:
"Significant patch series in this pull request:
- "mseal cleanups" (Lorenzo Stoakes)
Some mseal cleaning with no intended functional change.
- "Optimizations for khugepaged" (David Hildenbrand)
Improve khugepaged throughput by batching PTE operations for large
folios. This gain is mainly for arm64.
- "x86: enable EXECMEM_ROX_CACHE for ftrace and kprobes" (Mike Rapoport)
A bugfix, additional debug code and cleanups to the execmem code.
- "mm/shmem, swap: bugfix and improvement of mTHP swap in" (Kairui Song)
Bugfixes, cleanups and performance improvememnts to the mTHP swapin
code"
* tag 'mm-stable-2025-08-03-12-35' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (38 commits)
mm: mempool: fix crash in mempool_free() for zero-minimum pools
mm: correct type for vmalloc vm_flags fields
mm/shmem, swap: fix major fault counting
mm/shmem, swap: rework swap entry and index calculation for large swapin
mm/shmem, swap: simplify swapin path and result handling
mm/shmem, swap: never use swap cache and readahead for SWP_SYNCHRONOUS_IO
mm/shmem, swap: tidy up swap entry splitting
mm/shmem, swap: tidy up THP swapin checks
mm/shmem, swap: avoid redundant Xarray lookup during swapin
x86/ftrace: enable EXECMEM_ROX_CACHE for ftrace allocations
x86/kprobes: enable EXECMEM_ROX_CACHE for kprobes allocations
execmem: drop writable parameter from execmem_fill_trapping_insns()
execmem: add fallback for failures in vmalloc(VM_ALLOW_HUGE_VMAP)
execmem: move execmem_force_rw() and execmem_restore_rox() before use
execmem: rework execmem_cache_free()
execmem: introduce execmem_alloc_rw()
execmem: drop unused execmem_update_copy()
mm: fix a UAF when vma->mm is freed after vma->vm_refcnt got dropped
mm/rmap: add anon_vma lifetime debug check
mm: remove mm/io-mapping.c
...
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Kairui Song
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de55be4237 |
mm/shmem, swap: fix major fault counting
If the swapin failed, don't update the major fault count. There is a long existing comment for doing it this way, now with previous cleanups, we can finally fix it. Link: https://lkml.kernel.org/r/20250728075306.12704-9-ryncsn@gmail.com Signed-off-by: Kairui Song <kasong@tencent.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Kairui Song
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93c0476e70 |
mm/shmem, swap: rework swap entry and index calculation for large swapin
Instead of calculating the swap entry differently in different swapin paths, calculate it early before the swap cache lookup and use that for the lookup and later swapin. And after swapin have brought a folio, simply round it down against the size of the folio. This is simple and effective enough to verify the swap value. A folio's swap entry is always aligned by its size. Any kind of parallel split or race is acceptable because the final shmem_add_to_page_cache ensures that all entries covered by the folio are correct, and thus there will be no data corruption. This also prevents false positive cache lookup. If a shmem read request's index points to the middle of a large swap entry, previously, shmem will try the swap cache lookup using the large swap entry's starting value (which is the first sub swap entry of this large entry). This will lead to false positive lookup results if only the first few swap entries are cached but the actual requested swap entry pointed by the index is uncached. This is not a rare event, as swap readahead always tries to cache order 0 folios when possible. And this shouldn't cause any increased repeated faults. Instead, no matter how the shmem mapping is split in parallel, as long as the mapping still contains the right entries, the swapin will succeed. The final object size and stack usage are also reduced due to simplified code: ./scripts/bloat-o-meter mm/shmem.o.old mm/shmem.o add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-145 (-145) Function old new delta shmem_swapin_folio 4056 3911 -145 Total: Before=33242, After=33097, chg -0.44% Stack usage (Before vs After): mm/shmem.c:2314:12:shmem_swapin_folio 264 static mm/shmem.c:2314:12:shmem_swapin_folio 256 static And while at it, round down the index too if swap entry is round down. The index is used either for folio reallocation or confirming the mapping content. In either case, it should be aligned with the swap folio. Link: https://lkml.kernel.org/r/20250728075306.12704-8-ryncsn@gmail.com Signed-off-by: Kairui Song <kasong@tencent.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Kairui Song
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1326359f22 |
mm/shmem, swap: simplify swapin path and result handling
Slightly tidy up the different handling of swap in and error handling for SWP_SYNCHRONOUS_IO and non-SWP_SYNCHRONOUS_IO devices. Now swapin will always use either shmem_swap_alloc_folio or shmem_swapin_cluster, then check the result. Simplify the control flow and avoid a redundant goto label. Link: https://lkml.kernel.org/r/20250728075306.12704-7-ryncsn@gmail.com Signed-off-by: Kairui Song <kasong@tencent.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Kairui Song
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69805ea79d |
mm/shmem, swap: never use swap cache and readahead for SWP_SYNCHRONOUS_IO
For SWP_SYNCHRONOUS_IO devices, if a cache bypassing THP swapin failed due to reasons like memory pressure, partially conflicting swap cache or ZSWAP enabled, shmem will fallback to cached order 0 swapin. Right now the swap cache still has a non-trivial overhead, and readahead is not helpful for SWP_SYNCHRONOUS_IO devices, so we should always skip the readahead and swap cache even if the swapin falls back to order 0. So handle the fallback logic without falling back to the cached read. Link: https://lkml.kernel.org/r/20250728075306.12704-6-ryncsn@gmail.com Signed-off-by: Kairui Song <kasong@tencent.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Kairui Song
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91ab656ece |
mm/shmem, swap: tidy up swap entry splitting
Instead of keeping different paths of splitting the entry before the swap in start, move the entry splitting after the swapin has put the folio in swap cache (or set the SWAP_HAS_CACHE bit). This way we only need one place and one unified way to split the large entry. Whenever swapin brought in a folio smaller than the shmem swap entry, split the entry and recalculate the entry and index for verification. This removes duplicated codes and function calls, reduces LOC, and the split is less racy as it's guarded by swap cache now. So it will have a lower chance of repeated faults due to raced split. The compiler is also able to optimize the coder further: bloat-o-meter results with GCC 14: With DEBUG_SECTION_MISMATCH (-fno-inline-functions-called-once): ./scripts/bloat-o-meter mm/shmem.o.old mm/shmem.o add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-143 (-143) Function old new delta shmem_swapin_folio 2358 2215 -143 Total: Before=32933, After=32790, chg -0.43% With !DEBUG_SECTION_MISMATCH: add/remove: 0/1 grow/shrink: 1/0 up/down: 1069/-749 (320) Function old new delta shmem_swapin_folio 2871 3940 +1069 shmem_split_large_entry.isra 749 - -749 Total: Before=32806, After=33126, chg +0.98% Since shmem_split_large_entry is only called in one place now. The compiler will either generate more compact code, or inlined it for better performance. Link: https://lkml.kernel.org/r/20250728075306.12704-5-ryncsn@gmail.com Signed-off-by: Kairui Song <kasong@tencent.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Kairui Song
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c262ffd72c |
mm/shmem, swap: tidy up THP swapin checks
Move all THP swapin related checks under CONFIG_TRANSPARENT_HUGEPAGE, so they will be trimmed off by the compiler if not needed. And add a WARN if shmem sees a order > 0 entry when CONFIG_TRANSPARENT_HUGEPAGE is disabled, that should never happen unless things went very wrong. There should be no observable feature change except the new added WARN. Link: https://lkml.kernel.org/r/20250728075306.12704-4-ryncsn@gmail.com Signed-off-by: Kairui Song <kasong@tencent.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Kairui Song
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0cfc0e7e3d |
mm/shmem, swap: avoid redundant Xarray lookup during swapin
Patch series "mm/shmem, swap: bugfix and improvement of mTHP swap in", v6. The current THP swapin path have several problems. It may potentially hang, may cause redundant faults due to false positive swap cache lookup, and it issues redundant Xarray walks. !CONFIG_TRANSPARENT_HUGEPAGE builds may also contain unnecessary THP checks. This series fixes all of the mentioned issues, the code should be more robust and prepared for the swap table series. Now 4 walks is reduced to 3 (get order & confirm, confirm, insert folio), !CONFIG_TRANSPARENT_HUGEPAGE build overhead is also minimized, and comes with a sanity check now. The performance is slightly better after this series, sequential swap in of 24G data from ZRAM, using transparent_hugepage_tmpfs=always (24 samples each): Before: avg: 10.66s, stddev: 0.04 After patch 1: avg: 10.58s, stddev: 0.04 After patch 2: avg: 10.65s, stddev: 0.05 After patch 3: avg: 10.65s, stddev: 0.04 After patch 4: avg: 10.67s, stddev: 0.04 After patch 5: avg: 9.79s, stddev: 0.04 After patch 6: avg: 9.79s, stddev: 0.05 After patch 7: avg: 9.78s, stddev: 0.05 After patch 8: avg: 9.79s, stddev: 0.04 Several patches improve the performance by a little, which is about ~8% faster in total. Build kernel test showed very slightly improvement, testing with make -j48 with defconfig in a 768M memcg also using ZRAM as swap, and transparent_hugepage_tmpfs=always (6 test runs): Before: avg: 3334.66s, stddev: 43.76 After patch 1: avg: 3349.77s, stddev: 18.55 After patch 2: avg: 3325.01s, stddev: 42.96 After patch 3: avg: 3354.58s, stddev: 14.62 After patch 4: avg: 3336.24s, stddev: 32.15 After patch 5: avg: 3325.13s, stddev: 22.14 After patch 6: avg: 3285.03s, stddev: 38.95 After patch 7: avg: 3287.32s, stddev: 26.37 After patch 8: avg: 3295.87s, stddev: 46.24 This patch (of 7): Currently shmem calls xa_get_order to get the swap radix entry order, requiring a full tree walk. This can be easily combined with the swap entry value checking (shmem_confirm_swap) to avoid the duplicated lookup and abort early if the entry is gone already. Which should improve the performance. Link: https://lkml.kernel.org/r/20250728075306.12704-1-ryncsn@gmail.com Link: https://lkml.kernel.org/r/20250728075306.12704-3-ryncsn@gmail.com Signed-off-by: Kairui Song <kasong@tencent.com> Reviewed-by: Kemeng Shi <shikemeng@huaweicloud.com> Reviewed-by: Dev Jain <dev.jain@arm.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Baolin Wang
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8d58d65621 |
mm: shmem: fix the shmem large folio allocation for the i915 driver
After commit |
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Kairui Song
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5c241ed8d0 |
mm/shmem, swap: improve cached mTHP handling and fix potential hang
The current swap-in code assumes that, when a swap entry in shmem mapping
is order 0, its cached folios (if present) must be order 0 too, which
turns out not always correct.
The problem is shmem_split_large_entry is called before verifying the
folio will eventually be swapped in, one possible race is:
CPU1 CPU2
shmem_swapin_folio
/* swap in of order > 0 swap entry S1 */
folio = swap_cache_get_folio
/* folio = NULL */
order = xa_get_order
/* order > 0 */
folio = shmem_swap_alloc_folio
/* mTHP alloc failure, folio = NULL */
<... Interrupted ...>
shmem_swapin_folio
/* S1 is swapped in */
shmem_writeout
/* S1 is swapped out, folio cached */
shmem_split_large_entry(..., S1)
/* S1 is split, but the folio covering it has order > 0 now */
Now any following swapin of S1 will hang: `xa_get_order` returns 0, and
folio lookup will return a folio with order > 0. The
`xa_get_order(&mapping->i_pages, index) != folio_order(folio)` will always
return false causing swap-in to return -EEXIST.
And this looks fragile. So fix this up by allowing seeing a larger folio
in swap cache, and check the whole shmem mapping range covered by the
swapin have the right swap value upon inserting the folio. And drop the
redundant tree walks before the insertion.
This will actually improve performance, as it avoids two redundant Xarray
tree walks in the hot path, and the only side effect is that in the
failure path, shmem may redundantly reallocate a few folios causing
temporary slight memory pressure.
And worth noting, it may seems the order and value check before inserting
might help reducing the lock contention, which is not true. The swap
cache layer ensures raced swapin will either see a swap cache folio or
failed to do a swapin (we have SWAP_HAS_CACHE bit even if swap cache is
bypassed), so holding the folio lock and checking the folio flag is
already good enough for avoiding the lock contention. The chance that a
folio passes the swap entry value check but the shmem mapping slot has
changed should be very low.
Link: https://lkml.kernel.org/r/20250728075306.12704-1-ryncsn@gmail.com
Link: https://lkml.kernel.org/r/20250728075306.12704-2-ryncsn@gmail.com
Fixes:
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Linus Torvalds
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beace86e61 |
Summary of significant series in this pull request:
- The 4 patch series "mm: ksm: prevent KSM from breaking merging of new
VMAs" from Lorenzo Stoakes addresses an issue with KSM's
PR_SET_MEMORY_MERGE mode: newly mapped VMAs were not eligible for
merging with existing adjacent VMAs.
- The 4 patch series "mm/damon: introduce DAMON_STAT for simple and
practical access monitoring" from SeongJae Park adds a new kernel module
which simplifies the setup and usage of DAMON in production
environments.
- The 6 patch series "stop passing a writeback_control to swap/shmem
writeout" from Christoph Hellwig is a cleanup to the writeback code
which removes a couple of pointers from struct writeback_control.
- The 7 patch series "drivers/base/node.c: optimization and cleanups"
from Donet Tom contains largely uncorrelated cleanups to the NUMA node
setup and management code.
- The 4 patch series "mm: userfaultfd: assorted fixes and cleanups" from
Tal Zussman does some maintenance work on the userfaultfd code.
- The 5 patch series "Readahead tweaks for larger folios" from Ryan
Roberts implements some tuneups for pagecache readahead when it is
reading into order>0 folios.
- The 4 patch series "selftests/mm: Tweaks to the cow test" from Mark
Brown provides some cleanups and consistency improvements to the
selftests code.
- The 4 patch series "Optimize mremap() for large folios" from Dev Jain
does that. A 37% reduction in execution time was measured in a
memset+mremap+munmap microbenchmark.
- The 5 patch series "Remove zero_user()" from Matthew Wilcox expunges
zero_user() in favor of the more modern memzero_page().
- The 3 patch series "mm/huge_memory: vmf_insert_folio_*() and
vmf_insert_pfn_pud() fixes" from David Hildenbrand addresses some warts
which David noticed in the huge page code. These were not known to be
causing any issues at this time.
- The 3 patch series "mm/damon: use alloc_migrate_target() for
DAMOS_MIGRATE_{HOT,COLD" from SeongJae Park provides some cleanup and
consolidation work in DAMON.
- The 3 patch series "use vm_flags_t consistently" from Lorenzo Stoakes
uses vm_flags_t in places where we were inappropriately using other
types.
- The 3 patch series "mm/memfd: Reserve hugetlb folios before
allocation" from Vivek Kasireddy increases the reliability of large page
allocation in the memfd code.
- The 14 patch series "mm: Remove pXX_devmap page table bit and pfn_t
type" from Alistair Popple removes several now-unneeded PFN_* flags.
- The 5 patch series "mm/damon: decouple sysfs from core" from SeongJae
Park implememnts some cleanup and maintainability work in the DAMON
sysfs layer.
- The 5 patch series "madvise cleanup" from Lorenzo Stoakes does quite a
lot of cleanup/maintenance work in the madvise() code.
- The 4 patch series "madvise anon_name cleanups" from Vlastimil Babka
provides additional cleanups on top or Lorenzo's effort.
- The 11 patch series "Implement numa node notifier" from Oscar Salvador
creates a standalone notifier for NUMA node memory state changes.
Previously these were lumped under the more general memory on/offline
notifier.
- The 6 patch series "Make MIGRATE_ISOLATE a standalone bit" from Zi Yan
cleans up the pageblock isolation code and fixes a potential issue which
doesn't seem to cause any problems in practice.
- The 5 patch series "selftests/damon: add python and drgn based DAMON
sysfs functionality tests" from SeongJae Park adds additional drgn- and
python-based DAMON selftests which are more comprehensive than the
existing selftest suite.
- The 5 patch series "Misc rework on hugetlb faulting path" from Oscar
Salvador fixes a rather obscure deadlock in the hugetlb fault code and
follows that fix with a series of cleanups.
- The 3 patch series "cma: factor out allocation logic from
__cma_declare_contiguous_nid" from Mike Rapoport rationalizes and cleans
up the highmem-specific code in the CMA allocator.
- The 28 patch series "mm/migration: rework movable_ops page migration
(part 1)" from David Hildenbrand provides cleanups and
future-preparedness to the migration code.
- The 2 patch series "mm/damon: add trace events for auto-tuned
monitoring intervals and DAMOS quota" from SeongJae Park adds some
tracepoints to some DAMON auto-tuning code.
- The 6 patch series "mm/damon: fix misc bugs in DAMON modules" from
SeongJae Park does that.
- The 6 patch series "mm/damon: misc cleanups" from SeongJae Park also
does what it claims.
- The 4 patch series "mm: folio_pte_batch() improvements" from David
Hildenbrand cleans up the large folio PTE batching code.
- The 13 patch series "mm/damon/vaddr: Allow interleaving in
migrate_{hot,cold} actions" from SeongJae Park facilitates dynamic
alteration of DAMON's inter-node allocation policy.
- The 3 patch series "Remove unmap_and_put_page()" from Vishal Moola
provides a couple of page->folio conversions.
- The 4 patch series "mm: per-node proactive reclaim" from Davidlohr
Bueso implements a per-node control of proactive reclaim - beyond the
current memcg-based implementation.
- The 14 patch series "mm/damon: remove damon_callback" from SeongJae
Park replaces the damon_callback interface with a more general and
powerful damon_call()+damos_walk() interface.
- The 10 patch series "mm/mremap: permit mremap() move of multiple VMAs"
from Lorenzo Stoakes implements a number of mremap cleanups (of course)
in preparation for adding new mremap() functionality: newly permit the
remapping of multiple VMAs when the user is specifying MREMAP_FIXED. It
still excludes some specialized situations where this cannot be
performed reliably.
- The 3 patch series "drop hugetlb_free_pgd_range()" from Anthony Yznaga
switches some sparc hugetlb code over to the generic version and removes
the thus-unneeded hugetlb_free_pgd_range().
- The 4 patch series "mm/damon/sysfs: support periodic and automated
stats update" from SeongJae Park augments the present
userspace-requested update of DAMON sysfs monitoring files. Automatic
update is now provided, along with a tunable to control the update
interval.
- The 4 patch series "Some randome fixes and cleanups to swapfile" from
Kemeng Shi does what is claims.
- The 4 patch series "mm: introduce snapshot_page" from Luiz Capitulino
and David Hildenbrand provides (and uses) a means by which debug-style
functions can grab a copy of a pageframe and inspect it locklessly
without tripping over the races inherent in operating on the live
pageframe directly.
- The 6 patch series "use per-vma locks for /proc/pid/maps reads" from
Suren Baghdasaryan addresses the large contention issues which can be
triggered by reads from that procfs file. Latencies are reduced by more
than half in some situations. The series also introduces several new
selftests for the /proc/pid/maps interface.
- The 6 patch series "__folio_split() clean up" from Zi Yan cleans up
__folio_split()!
- The 7 patch series "Optimize mprotect() for large folios" from Dev
Jain provides some quite large (>3x) speedups to mprotect() when dealing
with large folios.
- The 2 patch series "selftests/mm: reuse FORCE_READ to replace "asm
volatile("" : "+r" (XXX));" and some cleanup" from wang lian does some
cleanup work in the selftests code.
- The 3 patch series "tools/testing: expand mremap testing" from Lorenzo
Stoakes extends the mremap() selftest in several ways, including adding
more checking of Lorenzo's recently added "permit mremap() move of
multiple VMAs" feature.
- The 22 patch series "selftests/damon/sysfs.py: test all parameters"
from SeongJae Park extends the DAMON sysfs interface selftest so that it
tests all possible user-requested parameters. Rather than the present
minimal subset.
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Merge tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
"As usual, many cleanups. The below blurbiage describes 42 patchsets.
21 of those are partially or fully cleanup work. "cleans up",
"cleanup", "maintainability", "rationalizes", etc.
I never knew the MM code was so dirty.
"mm: ksm: prevent KSM from breaking merging of new VMAs" (Lorenzo Stoakes)
addresses an issue with KSM's PR_SET_MEMORY_MERGE mode: newly
mapped VMAs were not eligible for merging with existing adjacent
VMAs.
"mm/damon: introduce DAMON_STAT for simple and practical access monitoring" (SeongJae Park)
adds a new kernel module which simplifies the setup and usage of
DAMON in production environments.
"stop passing a writeback_control to swap/shmem writeout" (Christoph Hellwig)
is a cleanup to the writeback code which removes a couple of
pointers from struct writeback_control.
"drivers/base/node.c: optimization and cleanups" (Donet Tom)
contains largely uncorrelated cleanups to the NUMA node setup and
management code.
"mm: userfaultfd: assorted fixes and cleanups" (Tal Zussman)
does some maintenance work on the userfaultfd code.
"Readahead tweaks for larger folios" (Ryan Roberts)
implements some tuneups for pagecache readahead when it is reading
into order>0 folios.
"selftests/mm: Tweaks to the cow test" (Mark Brown)
provides some cleanups and consistency improvements to the
selftests code.
"Optimize mremap() for large folios" (Dev Jain)
does that. A 37% reduction in execution time was measured in a
memset+mremap+munmap microbenchmark.
"Remove zero_user()" (Matthew Wilcox)
expunges zero_user() in favor of the more modern memzero_page().
"mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes" (David Hildenbrand)
addresses some warts which David noticed in the huge page code.
These were not known to be causing any issues at this time.
"mm/damon: use alloc_migrate_target() for DAMOS_MIGRATE_{HOT,COLD" (SeongJae Park)
provides some cleanup and consolidation work in DAMON.
"use vm_flags_t consistently" (Lorenzo Stoakes)
uses vm_flags_t in places where we were inappropriately using other
types.
"mm/memfd: Reserve hugetlb folios before allocation" (Vivek Kasireddy)
increases the reliability of large page allocation in the memfd
code.
"mm: Remove pXX_devmap page table bit and pfn_t type" (Alistair Popple)
removes several now-unneeded PFN_* flags.
"mm/damon: decouple sysfs from core" (SeongJae Park)
implememnts some cleanup and maintainability work in the DAMON
sysfs layer.
"madvise cleanup" (Lorenzo Stoakes)
does quite a lot of cleanup/maintenance work in the madvise() code.
"madvise anon_name cleanups" (Vlastimil Babka)
provides additional cleanups on top or Lorenzo's effort.
"Implement numa node notifier" (Oscar Salvador)
creates a standalone notifier for NUMA node memory state changes.
Previously these were lumped under the more general memory
on/offline notifier.
"Make MIGRATE_ISOLATE a standalone bit" (Zi Yan)
cleans up the pageblock isolation code and fixes a potential issue
which doesn't seem to cause any problems in practice.
"selftests/damon: add python and drgn based DAMON sysfs functionality tests" (SeongJae Park)
adds additional drgn- and python-based DAMON selftests which are
more comprehensive than the existing selftest suite.
"Misc rework on hugetlb faulting path" (Oscar Salvador)
fixes a rather obscure deadlock in the hugetlb fault code and
follows that fix with a series of cleanups.
"cma: factor out allocation logic from __cma_declare_contiguous_nid" (Mike Rapoport)
rationalizes and cleans up the highmem-specific code in the CMA
allocator.
"mm/migration: rework movable_ops page migration (part 1)" (David Hildenbrand)
provides cleanups and future-preparedness to the migration code.
"mm/damon: add trace events for auto-tuned monitoring intervals and DAMOS quota" (SeongJae Park)
adds some tracepoints to some DAMON auto-tuning code.
"mm/damon: fix misc bugs in DAMON modules" (SeongJae Park)
does that.
"mm/damon: misc cleanups" (SeongJae Park)
also does what it claims.
"mm: folio_pte_batch() improvements" (David Hildenbrand)
cleans up the large folio PTE batching code.
"mm/damon/vaddr: Allow interleaving in migrate_{hot,cold} actions" (SeongJae Park)
facilitates dynamic alteration of DAMON's inter-node allocation
policy.
"Remove unmap_and_put_page()" (Vishal Moola)
provides a couple of page->folio conversions.
"mm: per-node proactive reclaim" (Davidlohr Bueso)
implements a per-node control of proactive reclaim - beyond the
current memcg-based implementation.
"mm/damon: remove damon_callback" (SeongJae Park)
replaces the damon_callback interface with a more general and
powerful damon_call()+damos_walk() interface.
"mm/mremap: permit mremap() move of multiple VMAs" (Lorenzo Stoakes)
implements a number of mremap cleanups (of course) in preparation
for adding new mremap() functionality: newly permit the remapping
of multiple VMAs when the user is specifying MREMAP_FIXED. It still
excludes some specialized situations where this cannot be performed
reliably.
"drop hugetlb_free_pgd_range()" (Anthony Yznaga)
switches some sparc hugetlb code over to the generic version and
removes the thus-unneeded hugetlb_free_pgd_range().
"mm/damon/sysfs: support periodic and automated stats update" (SeongJae Park)
augments the present userspace-requested update of DAMON sysfs
monitoring files. Automatic update is now provided, along with a
tunable to control the update interval.
"Some randome fixes and cleanups to swapfile" (Kemeng Shi)
does what is claims.
"mm: introduce snapshot_page" (Luiz Capitulino and David Hildenbrand)
provides (and uses) a means by which debug-style functions can grab
a copy of a pageframe and inspect it locklessly without tripping
over the races inherent in operating on the live pageframe
directly.
"use per-vma locks for /proc/pid/maps reads" (Suren Baghdasaryan)
addresses the large contention issues which can be triggered by
reads from that procfs file. Latencies are reduced by more than
half in some situations. The series also introduces several new
selftests for the /proc/pid/maps interface.
"__folio_split() clean up" (Zi Yan)
cleans up __folio_split()!
"Optimize mprotect() for large folios" (Dev Jain)
provides some quite large (>3x) speedups to mprotect() when dealing
with large folios.
"selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup" (wang lian)
does some cleanup work in the selftests code.
"tools/testing: expand mremap testing" (Lorenzo Stoakes)
extends the mremap() selftest in several ways, including adding
more checking of Lorenzo's recently added "permit mremap() move of
multiple VMAs" feature.
"selftests/damon/sysfs.py: test all parameters" (SeongJae Park)
extends the DAMON sysfs interface selftest so that it tests all
possible user-requested parameters. Rather than the present minimal
subset"
* tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (370 commits)
MAINTAINERS: add missing headers to mempory policy & migration section
MAINTAINERS: add missing file to cgroup section
MAINTAINERS: add MM MISC section, add missing files to MISC and CORE
MAINTAINERS: add missing zsmalloc file
MAINTAINERS: add missing files to page alloc section
MAINTAINERS: add missing shrinker files
MAINTAINERS: move memremap.[ch] to hotplug section
MAINTAINERS: add missing mm_slot.h file THP section
MAINTAINERS: add missing interval_tree.c to memory mapping section
MAINTAINERS: add missing percpu-internal.h file to per-cpu section
mm/page_alloc: remove trace_mm_alloc_contig_migrate_range_info()
selftests/damon: introduce _common.sh to host shared function
selftests/damon/sysfs.py: test runtime reduction of DAMON parameters
selftests/damon/sysfs.py: test non-default parameters runtime commit
selftests/damon/sysfs.py: generalize DAMON context commit assertion
selftests/damon/sysfs.py: generalize monitoring attributes commit assertion
selftests/damon/sysfs.py: generalize DAMOS schemes commit assertion
selftests/damon/sysfs.py: test DAMOS filters commitment
selftests/damon/sysfs.py: generalize DAMOS scheme commit assertion
selftests/damon/sysfs.py: test DAMOS destinations commitment
...
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Linus Torvalds
|
57fcb7d930 |
vfs-6.17-rc1.fileattr
-----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaINCpgAKCRCRxhvAZXjc oqfFAQDcy3rROUF3W34KcSi7rDmaKVSX53d1tUoqH+1zDRpSlwEAriKDNC1ybudp YAnxVzkRHjHs1296WIuwKq5lfhJ60Q4= =geAl -----END PGP SIGNATURE----- Merge tag 'vfs-6.17-rc1.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull fileattr updates from Christian Brauner: "This introduces the new file_getattr() and file_setattr() system calls after lengthy discussions. Both system calls serve as successors and extensible companions to the FS_IOC_FSGETXATTR and FS_IOC_FSSETXATTR system calls which have started to show their age in addition to being named in a way that makes it easy to conflate them with extended attribute related operations. These syscalls allow userspace to set filesystem inode attributes on special files. One of the usage examples is the XFS quota projects. XFS has project quotas which could be attached to a directory. All new inodes in these directories inherit project ID set on parent directory. The project is created from userspace by opening and calling FS_IOC_FSSETXATTR on each inode. This is not possible for special files such as FIFO, SOCK, BLK etc. Therefore, some inodes are left with empty project ID. Those inodes then are not shown in the quota accounting but still exist in the directory. This is not critical but in the case when special files are created in the directory with already existing project quota, these new inodes inherit extended attributes. This creates a mix of special files with and without attributes. Moreover, special files with attributes don't have a possibility to become clear or change the attributes. This, in turn, prevents userspace from re-creating quota project on these existing files. In addition, these new system calls allow the implementation of additional attributes that we couldn't or didn't want to fit into the legacy ioctls anymore" * tag 'vfs-6.17-rc1.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: tighten a sanity check in file_attr_to_fileattr() tree-wide: s/struct fileattr/struct file_kattr/g fs: introduce file_getattr and file_setattr syscalls fs: prepare for extending file_get/setattr() fs: make vfs_fileattr_[get|set] return -EOPNOTSUPP selinux: implement inode_file_[g|s]etattr hooks lsm: introduce new hooks for setting/getting inode fsxattr fs: split fileattr related helpers into separate file |
|
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Linus Torvalds
|
7879d7aff0 |
vfs-6.17-rc1.misc
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Merge tag 'vfs-6.17-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc VFS updates from Christian Brauner:
"This contains the usual selections of misc updates for this cycle.
Features:
- Add ext4 IOCB_DONTCACHE support
This refactors the address_space_operations write_begin() and
write_end() callbacks to take const struct kiocb * as their first
argument, allowing IOCB flags such as IOCB_DONTCACHE to propagate
to the filesystem's buffered I/O path.
Ext4 is updated to implement handling of the IOCB_DONTCACHE flag
and advertises support via the FOP_DONTCACHE file operation flag.
Additionally, the i915 driver's shmem write paths are updated to
bypass the legacy write_begin/write_end interface in favor of
directly calling write_iter() with a constructed synchronous kiocb.
Another i915 change replaces a manual write loop with
kernel_write() during GEM shmem object creation.
Cleanups:
- don't duplicate vfs_open() in kernel_file_open()
- proc_fd_getattr(): don't bother with S_ISDIR() check
- fs/ecryptfs: replace snprintf with sysfs_emit in show function
- vfs: Remove unnecessary list_for_each_entry_safe() from
evict_inodes()
- filelock: add new locks_wake_up_waiter() helper
- fs: Remove three arguments from block_write_end()
- VFS: change old_dir and new_dir in struct renamedata to dentrys
- netfs: Remove unused declaration netfs_queue_write_request()
Fixes:
- eventpoll: Fix semi-unbounded recursion
- eventpoll: fix sphinx documentation build warning
- fs/read_write: Fix spelling typo
- fs: annotate data race between poll_schedule_timeout() and
pollwake()
- fs/pipe: set FMODE_NOWAIT in create_pipe_files()
- docs/vfs: update references to i_mutex to i_rwsem
- fs/buffer: remove comment about hard sectorsize
- fs/buffer: remove the min and max limit checks in __getblk_slow()
- fs/libfs: don't assume blocksize <= PAGE_SIZE in
generic_check_addressable
- fs_context: fix parameter name in infofc() macro
- fs: Prevent file descriptor table allocations exceeding INT_MAX"
* tag 'vfs-6.17-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (24 commits)
netfs: Remove unused declaration netfs_queue_write_request()
eventpoll: fix sphinx documentation build warning
ext4: support uncached buffered I/O
mm/pagemap: add write_begin_get_folio() helper function
fs: change write_begin/write_end interface to take struct kiocb *
drm/i915: Refactor shmem_pwrite() to use kiocb and write_iter
drm/i915: Use kernel_write() in shmem object create
eventpoll: Fix semi-unbounded recursion
vfs: Remove unnecessary list_for_each_entry_safe() from evict_inodes()
fs/libfs: don't assume blocksize <= PAGE_SIZE in generic_check_addressable
fs/buffer: remove the min and max limit checks in __getblk_slow()
fs: Prevent file descriptor table allocations exceeding INT_MAX
fs: Remove three arguments from block_write_end()
fs/ecryptfs: replace snprintf with sysfs_emit in show function
fs: annotate suspected data race between poll_schedule_timeout() and pollwake()
docs/vfs: update references to i_mutex to i_rwsem
fs/buffer: remove comment about hard sectorsize
fs_context: fix parameter name in infofc() macro
VFS: change old_dir and new_dir in struct renamedata to dentrys
proc_fd_getattr(): don't bother with S_ISDIR() check
...
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Linus Torvalds
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11fe69fbd5 |
Current exclusion rules for ->d_flags stores are rather unpleasant.
The basic rules are simple: * stores to dentry->d_flags are OK under dentry->d_lock. * stores to dentry->d_flags are OK in the dentry constructor, before becomes potentially visible to other threads. Unfortunately, there's a couple of exceptions to that, and that's where the headache comes from. Main PITA comes from d_set_d_op(); that primitive sets ->d_op of dentry and adjusts the flags that correspond to presence of individual methods. It's very easy to misuse; existing uses _are_ safe, but proof of correctness is brittle. Use in __d_alloc() is safe (we are within a constructor), but we might as well precalculate the initial value of ->d_flags when we set the default ->d_op for given superblock and set ->d_flags directly instead of messing with that helper. The reasons why other uses are safe are bloody convoluted; I'm not going to reproduce it here. See https://lore.kernel.org/all/20250224010624.GT1977892@ZenIV/ for gory details, if you care. The critical part is using d_set_d_op() only just prior to d_splice_alias(), which makes a combination of d_splice_alias() with setting ->d_op, etc. a natural replacement primitive. Better yet, if we go that way, it's easy to take setting ->d_op and modifying ->d_flags under ->d_lock, which eliminates the headache as far as ->d_flags exclusion rules are concerned. Other exceptions are minor and easy to deal with. What this series does: * d_set_d_op() is no longer available; new primitive (d_splice_alias_ops()) is provided, equivalent to combination of d_set_d_op() and d_splice_alias(). * new field of struct super_block - ->s_d_flags. Default value of ->d_flags to be used when allocating dentries on this filesystem. * new primitive for setting ->s_d_op: set_default_d_op(). Replaces stores to ->s_d_op at mount time. All in-tree filesystems converted; out-of-tree ones will get caught by compiler (->s_d_op is renamed, so stores to it will be caught). ->s_d_flags is set by the same primitive to match the ->s_d_op. * a lot of filesystems had ->s_d_op->d_delete equal to always_delete_dentry; that is equivalent to setting DCACHE_DONTCACHE in ->d_flags, so such filesystems can bloody well set that bit in ->s_d_flags and drop ->d_delete() from dentry_operations. In quite a few cases that results in empty dentry_operations, which means that we can get rid of those. * kill simple_dentry_operations - not needed anymore. * massage d_alloc_parallel() to get rid of the other exception wrt ->d_flags stores - we can set DCACHE_PAR_LOOKUP as soon as we allocate the new dentry; no need to delay that until we commit to using the sucker. As the result, ->d_flags stores are all either under ->d_lock or done before the dentry becomes visible in any shared data structures. -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCaIQ/tQAKCRBZ7Krx/gZQ 66AhAQDgQ+S224x5YevNXc9mDoGUBMF4OG0n0fIla9rfdL4I6wEAqpOWMNDcVPCZ GwYOvJ9YuqNdz+MyprAI18Yza4GOmgs= =rTYB -----END PGP SIGNATURE----- Merge tag 'pull-dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull dentry d_flags updates from Al Viro: "The current exclusion rules for dentry->d_flags stores are rather unpleasant. The basic rules are simple: - stores to dentry->d_flags are OK under dentry->d_lock - stores to dentry->d_flags are OK in the dentry constructor, before becomes potentially visible to other threads Unfortunately, there's a couple of exceptions to that, and that's where the headache comes from. The main PITA comes from d_set_d_op(); that primitive sets ->d_op of dentry and adjusts the flags that correspond to presence of individual methods. It's very easy to misuse; existing uses _are_ safe, but proof of correctness is brittle. Use in __d_alloc() is safe (we are within a constructor), but we might as well precalculate the initial value of 'd_flags' when we set the default ->d_op for given superblock and set 'd_flags' directly instead of messing with that helper. The reasons why other uses are safe are bloody convoluted; I'm not going to reproduce it here. See [1] for gory details, if you care. The critical part is using d_set_d_op() only just prior to d_splice_alias(), which makes a combination of d_splice_alias() with setting ->d_op, etc a natural replacement primitive. Better yet, if we go that way, it's easy to take setting ->d_op and modifying 'd_flags' under ->d_lock, which eliminates the headache as far as 'd_flags' exclusion rules are concerned. Other exceptions are minor and easy to deal with. What this series does: - d_set_d_op() is no longer available; instead a new primitive (d_splice_alias_ops()) is provided, equivalent to combination of d_set_d_op() and d_splice_alias(). - new field of struct super_block - 's_d_flags'. This sets the default value of 'd_flags' to be used when allocating dentries on this filesystem. - new primitive for setting 's_d_op': set_default_d_op(). This replaces stores to 's_d_op' at mount time. All in-tree filesystems converted; out-of-tree ones will get caught by the compiler ('s_d_op' is renamed, so stores to it will be caught). 's_d_flags' is set by the same primitive to match the 's_d_op'. - a lot of filesystems had sb->s_d_op->d_delete equal to always_delete_dentry; that is equivalent to setting DCACHE_DONTCACHE in 'd_flags', so such filesystems can bloody well set that bit in 's_d_flags' and drop 'd_delete()' from dentry_operations. In quite a few cases that results in empty dentry_operations, which means that we can get rid of those. - kill simple_dentry_operations - not needed anymore - massage d_alloc_parallel() to get rid of the other exception wrt 'd_flags' stores - we can set DCACHE_PAR_LOOKUP as soon as we allocate the new dentry; no need to delay that until we commit to using the sucker. As the result, 'd_flags' stores are all either under ->d_lock or done before the dentry becomes visible in any shared data structures" Link: https://lore.kernel.org/all/20250224010624.GT1977892@ZenIV/ [1] * tag 'pull-dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (21 commits) configfs: use DCACHE_DONTCACHE debugfs: use DCACHE_DONTCACHE efivarfs: use DCACHE_DONTCACHE instead of always_delete_dentry() 9p: don't bother with always_delete_dentry ramfs, hugetlbfs, mqueue: set DCACHE_DONTCACHE kill simple_dentry_operations devpts, sunrpc, hostfs: don't bother with ->d_op shmem: no dentry retention past the refcount reaching zero d_alloc_parallel(): set DCACHE_PAR_LOOKUP earlier make d_set_d_op() static simple_lookup(): just set DCACHE_DONTCACHE tracefs: Add d_delete to remove negative dentries set_default_d_op(): calculate the matching value for ->d_flags correct the set of flags forbidden at d_set_d_op() time split d_flags calculation out of d_set_d_op() new helper: set_default_d_op() fuse: no need for special dentry_operations for root dentry switch procfs from d_set_d_op() to d_splice_alias_ops() new helper: d_splice_alias_ops() procfs: kill ->proc_dops ... |
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Hugh Dickins
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6344a6d9ce |
mm/shmem: writeout free swap if swap_writeout() reactivates
If swap_writeout() returns AOP_WRITEPAGE_ACTIVATE (for example, because zswap cannot compress and memcg disables writeback), there is no virtue in keeping that folio in swap cache and holding the swap allocation: shmem_writeout() switch it back to shmem page cache before returning. Folio lock is held, and folio->memcg_data remains set throughout, so there is no need to get into any memcg or memsw charge complications: swap_free_nr() and delete_from_swap_cache() do as much as is needed (but beware the race with shmem_free_swap() when inode truncated or evicted). Doing the same for an anonymous folio is harder, since it will usually have been unmapped, with references to the swap left in the page tables. Adding a function to remap the folio would be fun, but not worthwhile unless it has other uses, or an urgent bug with anon is demonstrated. [hughd@google.com: use shmem_recalc_inode() rather than open coding, per Baolin] Link: https://lkml.kernel.org/r/101a7d89-290c-545d-8a6d-b1174ed8b1e5@google.com Link: https://lkml.kernel.org/r/5c911f7a-af7a-5029-1dd4-2e00b66d565c@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Tested-by: David Rientjes <rientjes@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <21cnbao@gmail.com> Cc: Chris Li <chrisl@kernel.org> Cc: Kairui Song <ryncsn@gmail.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Shakeel Butt <shakeel.butt@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Hugh Dickins
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ea693aaa5c |
mm/shmem: hold shmem_swaplist spinlock (not mutex) much less
A flamegraph (from an MGLRU load) showed shmem_writeout()'s use of the global shmem_swaplist_mutex worryingly hot: improvement is long overdue. 3.1 commit |
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Taotao Chen
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e9d8e2bf23
|
fs: change write_begin/write_end interface to take struct kiocb *
Change the address_space_operations callbacks write_begin() and write_end() to take struct kiocb * as the first argument instead of struct file *. Update all affected function prototypes, implementations, call sites, and related documentation across VFS, filesystems, and block layer. Part of a series refactoring address_space_operations write_begin and write_end callbacks to use struct kiocb for passing write context and flags. Signed-off-by: Taotao Chen <chentaotao@didiglobal.com> Link: https://lore.kernel.org/20250716093559.217344-4-chentaotao@didiglobal.com Signed-off-by: Christian Brauner <brauner@kernel.org> |
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Lorenzo Stoakes
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bfbe71109f |
mm: update core kernel code to use vm_flags_t consistently
The core kernel code is currently very inconsistent in its use of vm_flags_t vs. unsigned long. This prevents us from changing the type of vm_flags_t in the future and is simply not correct, so correct this. While this results in rather a lot of churn, it is a critical pre-requisite for a future planned change to VMA flag type. Additionally, update VMA userland tests to account for the changes. To make review easier and to break things into smaller parts, driver and architecture-specific changes is left for a subsequent commit. The code has been adjusted to cascade the changes across all calling code as far as is needed. We will adjust architecture-specific and driver code in a subsequent patch. Overall, this patch does not introduce any functional change. Link: https://lkml.kernel.org/r/d1588e7bb96d1ea3fe7b9df2c699d5b4592d901d.1750274467.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Kees Cook <kees@kernel.org> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Jan Kara <jack@suse.cz> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Acked-by: Zi Yan <ziy@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Jann Horn <jannh@google.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Christoph Hellwig
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624043dbd5 |
mm: stop passing a writeback_control structure to swap_writeout
swap_writeout only needs the swap_iocb cookie from the writeback_control structure, so pass it explicitly. Link: https://lkml.kernel.org/r/20250610054959.2057526-6-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |