Commit graph

532 commits

Author SHA1 Message Date
Linus Torvalds
617a814f14 ALong with the usual shower of singleton patches, notable patch series in
this pull request are:
 
 "Align kvrealloc() with krealloc()" from Danilo Krummrich.  Adds
 consistency to the APIs and behaviour of these two core allocation
 functions.  This also simplifies/enables Rustification.
 
 "Some cleanups for shmem" from Baolin Wang.  No functional changes - mode
 code reuse, better function naming, logic simplifications.
 
 "mm: some small page fault cleanups" from Josef Bacik.  No functional
 changes - code cleanups only.
 
 "Various memory tiering fixes" from Zi Yan.  A small fix and a little
 cleanup.
 
 "mm/swap: remove boilerplate" from Yu Zhao.  Code cleanups and
 simplifications and .text shrinkage.
 
 "Kernel stack usage histogram" from Pasha Tatashin and Shakeel Butt.  This
 is a feature, it adds new feilds to /proc/vmstat such as
 
     $ grep kstack /proc/vmstat
     kstack_1k 3
     kstack_2k 188
     kstack_4k 11391
     kstack_8k 243
     kstack_16k 0
 
 which tells us that 11391 processes used 4k of stack while none at all
 used 16k.  Useful for some system tuning things, but partivularly useful
 for "the dynamic kernel stack project".
 
 "kmemleak: support for percpu memory leak detect" from Pavel Tikhomirov.
 Teaches kmemleak to detect leaksage of percpu memory.
 
 "mm: memcg: page counters optimizations" from Roman Gushchin.  "3
 independent small optimizations of page counters".
 
 "mm: split PTE/PMD PT table Kconfig cleanups+clarifications" from David
 Hildenbrand.  Improves PTE/PMD splitlock detection, makes powerpc/8xx work
 correctly by design rather than by accident.
 
 "mm: remove arch_make_page_accessible()" from David Hildenbrand.  Some
 folio conversions which make arch_make_page_accessible() unneeded.
 
 "mm, memcg: cg2 memory{.swap,}.peak write handlers" fro David Finkel.
 Cleans up and fixes our handling of the resetting of the cgroup/process
 peak-memory-use detector.
 
 "Make core VMA operations internal and testable" from Lorenzo Stoakes.
 Rationalizaion and encapsulation of the VMA manipulation APIs.  With a
 view to better enable testing of the VMA functions, even from a
 userspace-only harness.
 
 "mm: zswap: fixes for global shrinker" from Takero Funaki.  Fix issues in
 the zswap global shrinker, resulting in improved performance.
 
 "mm: print the promo watermark in zoneinfo" from Kaiyang Zhao.  Fill in
 some missing info in /proc/zoneinfo.
 
 "mm: replace follow_page() by folio_walk" from David Hildenbrand.  Code
 cleanups and rationalizations (conversion to folio_walk()) resulting in
 the removal of follow_page().
 
 "improving dynamic zswap shrinker protection scheme" from Nhat Pham.  Some
 tuning to improve zswap's dynamic shrinker.  Significant reductions in
 swapin and improvements in performance are shown.
 
 "mm: Fix several issues with unaccepted memory" from Kirill Shutemov.
 Improvements to the new unaccepted memory feature,
 
 "mm/mprotect: Fix dax puds" from Peter Xu.  Implements mprotect on DAX
 PUDs.  This was missing, although nobody seems to have notied yet.
 
 "Introduce a store type enum for the Maple tree" from Sidhartha Kumar.
 Cleanups and modest performance improvements for the maple tree library
 code.
 
 "memcg: further decouple v1 code from v2" from Shakeel Butt.  Move more
 cgroup v1 remnants away from the v2 memcg code.
 
 "memcg: initiate deprecation of v1 features" from Shakeel Butt.  Adds
 various warnings telling users that memcg v1 features are deprecated.
 
 "mm: swap: mTHP swap allocator base on swap cluster order" from Chris Li.
 Greatly improves the success rate of the mTHP swap allocation.
 
 "mm: introduce numa_memblks" from Mike Rapoport.  Moves various disparate
 per-arch implementations of numa_memblk code into generic code.
 
 "mm: batch free swaps for zap_pte_range()" from Barry Song.  Greatly
 improves the performance of munmap() of swap-filled ptes.
 
 "support large folio swap-out and swap-in for shmem" from Baolin Wang.
 With this series we no longer split shmem large folios into simgle-page
 folios when swapping out shmem.
 
 "mm/hugetlb: alloc/free gigantic folios" from Yu Zhao.  Nice performance
 improvements and code reductions for gigantic folios.
 
 "support shmem mTHP collapse" from Baolin Wang.  Adds support for
 khugepaged's collapsing of shmem mTHP folios.
 
 "mm: Optimize mseal checks" from Pedro Falcato.  Fixes an mprotect()
 performance regression due to the addition of mseal().
 
 "Increase the number of bits available in page_type" from Matthew Wilcox.
 Increases the number of bits available in page_type!
 
 "Simplify the page flags a little" from Matthew Wilcox.  Many legacy page
 flags are now folio flags, so the page-based flags and their
 accessors/mutators can be removed.
 
 "mm: store zero pages to be swapped out in a bitmap" from Usama Arif.  An
 optimization which permits us to avoid writing/reading zero-filled zswap
 pages to backing store.
 
 "Avoid MAP_FIXED gap exposure" from Liam Howlett.  Fixes a race window
 which occurs when a MAP_FIXED operqtion is occurring during an unrelated
 vma tree walk.
 
 "mm: remove vma_merge()" from Lorenzo Stoakes.  Major rotorooting of the
 vma_merge() functionality, making ot cleaner, more testable and better
 tested.
 
 "misc fixups for DAMON {self,kunit} tests" from SeongJae Park.  Minor
 fixups of DAMON selftests and kunit tests.
 
 "mm: memory_hotplug: improve do_migrate_range()" from Kefeng Wang.  Code
 cleanups and folio conversions.
 
 "Shmem mTHP controls and stats improvements" from Ryan Roberts.  Cleanups
 for shmem controls and stats.
 
 "mm: count the number of anonymous THPs per size" from Barry Song.  Expose
 additional anon THP stats to userspace for improved tuning.
 
 "mm: finish isolate/putback_lru_page()" from Kefeng Wang: more folio
 conversions and removal of now-unused page-based APIs.
 
 "replace per-quota region priorities histogram buffer with per-context
 one" from SeongJae Park.  DAMON histogram rationalization.
 
 "Docs/damon: update GitHub repo URLs and maintainer-profile" from SeongJae
 Park.  DAMON documentation updates.
 
 "mm/vdpa: correct misuse of non-direct-reclaim __GFP_NOFAIL and improve
 related doc and warn" from Jason Wang: fixes usage of page allocator
 __GFP_NOFAIL and GFP_ATOMIC flags.
 
 "mm: split underused THPs" from Yu Zhao.  Improve THP=always policy - this
 was overprovisioning THPs in sparsely accessed memory areas.
 
 "zram: introduce custom comp backends API" frm Sergey Senozhatsky.  Add
 support for zram run-time compression algorithm tuning.
 
 "mm: Care about shadow stack guard gap when getting an unmapped area" from
 Mark Brown.  Fix up the various arch_get_unmapped_area() implementations
 to better respect guard areas.
 
 "Improve mem_cgroup_iter()" from Kinsey Ho.  Improve the reliability of
 mem_cgroup_iter() and various code cleanups.
 
 "mm: Support huge pfnmaps" from Peter Xu.  Extends the usage of huge
 pfnmap support.
 
 "resource: Fix region_intersects() vs add_memory_driver_managed()" from
 Huang Ying.  Fix a bug in region_intersects() for systems with CXL memory.
 
 "mm: hwpoison: two more poison recovery" from Kefeng Wang.  Teaches a
 couple more code paths to correctly recover from the encountering of
 poisoned memry.
 
 "mm: enable large folios swap-in support" from Barry Song.  Support the
 swapin of mTHP memory into appropriately-sized folios, rather than into
 single-page folios.
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Merge tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:
 "Along with the usual shower of singleton patches, notable patch series
  in this pull request are:

   - "Align kvrealloc() with krealloc()" from Danilo Krummrich. Adds
     consistency to the APIs and behaviour of these two core allocation
     functions. This also simplifies/enables Rustification.

   - "Some cleanups for shmem" from Baolin Wang. No functional changes -
     mode code reuse, better function naming, logic simplifications.

   - "mm: some small page fault cleanups" from Josef Bacik. No
     functional changes - code cleanups only.

   - "Various memory tiering fixes" from Zi Yan. A small fix and a
     little cleanup.

   - "mm/swap: remove boilerplate" from Yu Zhao. Code cleanups and
     simplifications and .text shrinkage.

   - "Kernel stack usage histogram" from Pasha Tatashin and Shakeel
     Butt. This is a feature, it adds new feilds to /proc/vmstat such as

       $ grep kstack /proc/vmstat
       kstack_1k 3
       kstack_2k 188
       kstack_4k 11391
       kstack_8k 243
       kstack_16k 0

     which tells us that 11391 processes used 4k of stack while none at
     all used 16k. Useful for some system tuning things, but
     partivularly useful for "the dynamic kernel stack project".

   - "kmemleak: support for percpu memory leak detect" from Pavel
     Tikhomirov. Teaches kmemleak to detect leaksage of percpu memory.

   - "mm: memcg: page counters optimizations" from Roman Gushchin. "3
     independent small optimizations of page counters".

   - "mm: split PTE/PMD PT table Kconfig cleanups+clarifications" from
     David Hildenbrand. Improves PTE/PMD splitlock detection, makes
     powerpc/8xx work correctly by design rather than by accident.

   - "mm: remove arch_make_page_accessible()" from David Hildenbrand.
     Some folio conversions which make arch_make_page_accessible()
     unneeded.

   - "mm, memcg: cg2 memory{.swap,}.peak write handlers" fro David
     Finkel. Cleans up and fixes our handling of the resetting of the
     cgroup/process peak-memory-use detector.

   - "Make core VMA operations internal and testable" from Lorenzo
     Stoakes. Rationalizaion and encapsulation of the VMA manipulation
     APIs. With a view to better enable testing of the VMA functions,
     even from a userspace-only harness.

   - "mm: zswap: fixes for global shrinker" from Takero Funaki. Fix
     issues in the zswap global shrinker, resulting in improved
     performance.

   - "mm: print the promo watermark in zoneinfo" from Kaiyang Zhao. Fill
     in some missing info in /proc/zoneinfo.

   - "mm: replace follow_page() by folio_walk" from David Hildenbrand.
     Code cleanups and rationalizations (conversion to folio_walk())
     resulting in the removal of follow_page().

   - "improving dynamic zswap shrinker protection scheme" from Nhat
     Pham. Some tuning to improve zswap's dynamic shrinker. Significant
     reductions in swapin and improvements in performance are shown.

   - "mm: Fix several issues with unaccepted memory" from Kirill
     Shutemov. Improvements to the new unaccepted memory feature,

   - "mm/mprotect: Fix dax puds" from Peter Xu. Implements mprotect on
     DAX PUDs. This was missing, although nobody seems to have notied
     yet.

   - "Introduce a store type enum for the Maple tree" from Sidhartha
     Kumar. Cleanups and modest performance improvements for the maple
     tree library code.

   - "memcg: further decouple v1 code from v2" from Shakeel Butt. Move
     more cgroup v1 remnants away from the v2 memcg code.

   - "memcg: initiate deprecation of v1 features" from Shakeel Butt.
     Adds various warnings telling users that memcg v1 features are
     deprecated.

   - "mm: swap: mTHP swap allocator base on swap cluster order" from
     Chris Li. Greatly improves the success rate of the mTHP swap
     allocation.

   - "mm: introduce numa_memblks" from Mike Rapoport. Moves various
     disparate per-arch implementations of numa_memblk code into generic
     code.

   - "mm: batch free swaps for zap_pte_range()" from Barry Song. Greatly
     improves the performance of munmap() of swap-filled ptes.

   - "support large folio swap-out and swap-in for shmem" from Baolin
     Wang. With this series we no longer split shmem large folios into
     simgle-page folios when swapping out shmem.

   - "mm/hugetlb: alloc/free gigantic folios" from Yu Zhao. Nice
     performance improvements and code reductions for gigantic folios.

   - "support shmem mTHP collapse" from Baolin Wang. Adds support for
     khugepaged's collapsing of shmem mTHP folios.

   - "mm: Optimize mseal checks" from Pedro Falcato. Fixes an mprotect()
     performance regression due to the addition of mseal().

   - "Increase the number of bits available in page_type" from Matthew
     Wilcox. Increases the number of bits available in page_type!

   - "Simplify the page flags a little" from Matthew Wilcox. Many legacy
     page flags are now folio flags, so the page-based flags and their
     accessors/mutators can be removed.

   - "mm: store zero pages to be swapped out in a bitmap" from Usama
     Arif. An optimization which permits us to avoid writing/reading
     zero-filled zswap pages to backing store.

   - "Avoid MAP_FIXED gap exposure" from Liam Howlett. Fixes a race
     window which occurs when a MAP_FIXED operqtion is occurring during
     an unrelated vma tree walk.

   - "mm: remove vma_merge()" from Lorenzo Stoakes. Major rotorooting of
     the vma_merge() functionality, making ot cleaner, more testable and
     better tested.

   - "misc fixups for DAMON {self,kunit} tests" from SeongJae Park.
     Minor fixups of DAMON selftests and kunit tests.

   - "mm: memory_hotplug: improve do_migrate_range()" from Kefeng Wang.
     Code cleanups and folio conversions.

   - "Shmem mTHP controls and stats improvements" from Ryan Roberts.
     Cleanups for shmem controls and stats.

   - "mm: count the number of anonymous THPs per size" from Barry Song.
     Expose additional anon THP stats to userspace for improved tuning.

   - "mm: finish isolate/putback_lru_page()" from Kefeng Wang: more
     folio conversions and removal of now-unused page-based APIs.

   - "replace per-quota region priorities histogram buffer with
     per-context one" from SeongJae Park. DAMON histogram
     rationalization.

   - "Docs/damon: update GitHub repo URLs and maintainer-profile" from
     SeongJae Park. DAMON documentation updates.

   - "mm/vdpa: correct misuse of non-direct-reclaim __GFP_NOFAIL and
     improve related doc and warn" from Jason Wang: fixes usage of page
     allocator __GFP_NOFAIL and GFP_ATOMIC flags.

   - "mm: split underused THPs" from Yu Zhao. Improve THP=always policy.
     This was overprovisioning THPs in sparsely accessed memory areas.

   - "zram: introduce custom comp backends API" frm Sergey Senozhatsky.
     Add support for zram run-time compression algorithm tuning.

   - "mm: Care about shadow stack guard gap when getting an unmapped
     area" from Mark Brown. Fix up the various arch_get_unmapped_area()
     implementations to better respect guard areas.

   - "Improve mem_cgroup_iter()" from Kinsey Ho. Improve the reliability
     of mem_cgroup_iter() and various code cleanups.

   - "mm: Support huge pfnmaps" from Peter Xu. Extends the usage of huge
     pfnmap support.

   - "resource: Fix region_intersects() vs add_memory_driver_managed()"
     from Huang Ying. Fix a bug in region_intersects() for systems with
     CXL memory.

   - "mm: hwpoison: two more poison recovery" from Kefeng Wang. Teaches
     a couple more code paths to correctly recover from the encountering
     of poisoned memry.

   - "mm: enable large folios swap-in support" from Barry Song. Support
     the swapin of mTHP memory into appropriately-sized folios, rather
     than into single-page folios"

* tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (416 commits)
  zram: free secondary algorithms names
  uprobes: turn xol_area->pages[2] into xol_area->page
  uprobes: introduce the global struct vm_special_mapping xol_mapping
  Revert "uprobes: use vm_special_mapping close() functionality"
  mm: support large folios swap-in for sync io devices
  mm: add nr argument in mem_cgroup_swapin_uncharge_swap() helper to support large folios
  mm: fix swap_read_folio_zeromap() for large folios with partial zeromap
  mm/debug_vm_pgtable: Use pxdp_get() for accessing page table entries
  set_memory: add __must_check to generic stubs
  mm/vma: return the exact errno in vms_gather_munmap_vmas()
  memcg: cleanup with !CONFIG_MEMCG_V1
  mm/show_mem.c: report alloc tags in human readable units
  mm: support poison recovery from copy_present_page()
  mm: support poison recovery from do_cow_fault()
  resource, kunit: add test case for region_intersects()
  resource: make alloc_free_mem_region() works for iomem_resource
  mm: z3fold: deprecate CONFIG_Z3FOLD
  vfio/pci: implement huge_fault support
  mm/arm64: support large pfn mappings
  mm/x86: support large pfn mappings
  ...
2024-09-21 07:29:05 -07:00
Yuesong Li
0692fad55d mm:page-writeback: use folio_next_index() helper in writeback_iter()
Simplify code pattern of 'folio->index + folio_nr_pages(folio)' by using
the existing helper folio_next_index().

Link: https://lkml.kernel.org/r/20240821063112.4053157-1-liyuesong@vivo.com
Signed-off-by: Yuesong Li <liyuesong@vivo.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-03 21:15:46 -07:00
Qais Yousef
ae04f69de0 sched/rt: Rename realtime_{prio, task}() to rt_or_dl_{prio, task}()
Some find the name realtime overloaded. Use rt_or_dl() as an
alternative, hopefully better, name.

Suggested-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Qais Yousef <qyousef@layalina.io>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240610192018.1567075-4-qyousef@layalina.io
2024-08-07 18:32:38 +02:00
Qais Yousef
130fd056dd sched/rt: Clean up usage of rt_task()
rt_task() checks if a task has RT priority. But depends on your
dictionary, this could mean it belongs to RT class, or is a 'realtime'
task, which includes RT and DL classes.

Since this has caused some confusion already on discussion [1], it
seemed a clean up is due.

I define the usage of rt_task() to be tasks that belong to RT class.
Make sure that it returns true only for RT class and audit the users and
replace the ones required the old behavior with the new realtime_task()
which returns true for RT and DL classes. Introduce similar
realtime_prio() to create similar distinction to rt_prio() and update
the users that required the old behavior to use the new function.

Move MAX_DL_PRIO to prio.h so it can be used in the new definitions.

Document the functions to make it more obvious what is the difference
between them. PI-boosted tasks is a factor that must be taken into
account when choosing which function to use.

Rename task_is_realtime() to realtime_task_policy() as the old name is
confusing against the new realtime_task().

No functional changes were intended.

[1] https://lore.kernel.org/lkml/20240506100509.GL40213@noisy.programming.kicks-ass.net/

Signed-off-by: Qais Yousef <qyousef@layalina.io>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Reviewed-by: "Steven Rostedt (Google)" <rostedt@goodmis.org>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20240610192018.1567075-2-qyousef@layalina.io
2024-08-07 18:32:37 +02:00
Joel Granados
78eb4ea25c sysctl: treewide: constify the ctl_table argument of proc_handlers
const qualify the struct ctl_table argument in the proc_handler function
signatures. This is a prerequisite to moving the static ctl_table
structs into .rodata data which will ensure that proc_handler function
pointers cannot be modified.

This patch has been generated by the following coccinelle script:

```
  virtual patch

  @r1@
  identifier ctl, write, buffer, lenp, ppos;
  identifier func !~ "appldata_(timer|interval)_handler|sched_(rt|rr)_handler|rds_tcp_skbuf_handler|proc_sctp_do_(hmac_alg|rto_min|rto_max|udp_port|alpha_beta|auth|probe_interval)";
  @@

  int func(
  - struct ctl_table *ctl
  + const struct ctl_table *ctl
    ,int write, void *buffer, size_t *lenp, loff_t *ppos);

  @r2@
  identifier func, ctl, write, buffer, lenp, ppos;
  @@

  int func(
  - struct ctl_table *ctl
  + const struct ctl_table *ctl
    ,int write, void *buffer, size_t *lenp, loff_t *ppos)
  { ... }

  @r3@
  identifier func;
  @@

  int func(
  - struct ctl_table *
  + const struct ctl_table *
    ,int , void *, size_t *, loff_t *);

  @r4@
  identifier func, ctl;
  @@

  int func(
  - struct ctl_table *ctl
  + const struct ctl_table *ctl
    ,int , void *, size_t *, loff_t *);

  @r5@
  identifier func, write, buffer, lenp, ppos;
  @@

  int func(
  - struct ctl_table *
  + const struct ctl_table *
    ,int write, void *buffer, size_t *lenp, loff_t *ppos);

```

* Code formatting was adjusted in xfs_sysctl.c to comply with code
  conventions. The xfs_stats_clear_proc_handler,
  xfs_panic_mask_proc_handler and xfs_deprecated_dointvec_minmax where
  adjusted.

* The ctl_table argument in proc_watchdog_common was const qualified.
  This is called from a proc_handler itself and is calling back into
  another proc_handler, making it necessary to change it as part of the
  proc_handler migration.

Co-developed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Co-developed-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Joel Granados <j.granados@samsung.com>
2024-07-24 20:59:29 +02:00
Jan Kara
68ed2a394a mm: avoid overflows in dirty throttling logic
The dirty throttling logic is interspersed with assumptions that dirty
limits in PAGE_SIZE units fit into 32-bit (so that various multiplications
fit into 64-bits).  If limits end up being larger, we will hit overflows,
possible divisions by 0 etc.  Fix these problems by never allowing so
large dirty limits as they have dubious practical value anyway.  For
dirty_bytes / dirty_background_bytes interfaces we can just refuse to set
so large limits.  For dirty_ratio / dirty_background_ratio it isn't so
simple as the dirty limit is computed from the amount of available memory
which can change due to memory hotplug etc.  So when converting dirty
limits from ratios to numbers of pages, we just don't allow the result to
exceed UINT_MAX.

This is root-only triggerable problem which occurs when the operator
sets dirty limits to >16 TB.

Link: https://lkml.kernel.org/r/20240621144246.11148-2-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Zach O'Keefe <zokeefe@google.com>
Reviewed-By: Zach O'Keefe <zokeefe@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 19:30:15 -07:00
Jan Kara
8dfcffa370 Revert "mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again"
Patch series "mm: Avoid possible overflows in dirty throttling".

Dirty throttling logic assumes dirty limits in page units fit into
32-bits.  This patch series makes sure this is true (see patch 2/2 for
more details).


This patch (of 2):

This reverts commit 9319b64790.

The commit is broken in several ways.  Firstly, the removed (u64) cast
from the multiplication will introduce a multiplication overflow on 32-bit
archs if wb_thresh * bg_thresh >= 1<<32 (which is actually common - the
default settings with 4GB of RAM will trigger this).  Secondly, the
div64_u64() is unnecessarily expensive on 32-bit archs.  We have
div64_ul() in case we want to be safe & cheap.  Thirdly, if dirty
thresholds are larger than 1<<32 pages, then dirty balancing is going to
blow up in many other spectacular ways anyway so trying to fix one
possible overflow is just moot.

Link: https://lkml.kernel.org/r/20240621144017.30993-1-jack@suse.cz
Link: https://lkml.kernel.org/r/20240621144246.11148-1-jack@suse.cz
Fixes: 9319b64790 ("mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-By: Zach O'Keefe <zokeefe@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 19:30:15 -07:00
Kemeng Shi
8246291ecc writeback: factor out balance_wb_limits to remove repeated code
Factor out balance_wb_limits to remove repeated code

[shikemeng@huaweicloud.com: add comment]
  Link: https://lkml.kernel.org/r/20240606033547.344376-1-shikemeng@huaweicloud.com
[akpm@linux-foundation.org: s/fileds/fields/ in comment]
Link: https://lkml.kernel.org/r/20240514125254.142203-9-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 19:29:54 -07:00
Kemeng Shi
236d0f16eb writeback: factor out wb_dirty_exceeded to remove repeated code
Factor out wb_dirty_exceeded to remove repeated code

Link: https://lkml.kernel.org/r/20240514125254.142203-8-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 19:29:54 -07:00
Kemeng Shi
8c9918dedf writeback: factor out balance_domain_limits to remove repeated code
Factor out balance_domain_limits to remove repeated code.

Link: https://lkml.kernel.org/r/20240514125254.142203-7-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 19:29:54 -07:00
Kemeng Shi
2530e2399b writeback: factor out wb_dirty_freerun to remove more repeated freerun code
Factor out wb_dirty_freerun to remove more repeated freerun code.

Link: https://lkml.kernel.org/r/20240514125254.142203-6-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 19:29:54 -07:00
Kemeng Shi
9bb48a7038 writeback: factor out code of freerun to remove repeated code
Factor out code of freerun into new helper functions domain_poll_intv and
domain_dirty_freerun to remove repeated code.

Link: https://lkml.kernel.org/r/20240514125254.142203-5-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 19:29:54 -07:00
Kemeng Shi
6e20832968 writeback: factor out domain_over_bg_thresh to remove repeated code
Factor out domain_over_bg_thresh from wb_over_bg_thresh to remove repeated
code.

Link: https://lkml.kernel.org/r/20240514125254.142203-4-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 19:29:54 -07:00
Kemeng Shi
ba62d5cfe1 writeback: add general function domain_dirty_avail to calculate dirty and avail of domain
Add general function domain_dirty_avail to calculate dirty and avail for
either dirty limit or background writeback in either global domain or wb
domain.

Link: https://lkml.kernel.org/r/20240514125254.142203-3-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 19:29:53 -07:00
Kemeng Shi
7c0c629be5 writeback: factor out wb_bg_dirty_limits to remove repeated code
Patch series "Add helper functions to remove repeated code and improve
readability of cgroup writeback", v2.

This series adds a lot of helpers to remove repeated code between domain
and wb; dirty limit and dirty background; global domain and wb domain. 
The helpers also improve readability.  More details can be found in the
respective patches.

A simple domain hierarchy is tested:
global domain (> 20G)
	|
cgroup domain1(10G)
	|
	wb1
	|
	fio

Test steps:
/* make it easy to observe */
echo 300000 > /proc/sys/vm/dirty_expire_centisecs
echo 3000 > /proc/sys/vm/dirty_writeback_centisecs

/* create cgroup domain */
cd /sys/fs/cgroup
echo "+memory +io" > cgroup.subtree_control
mkdir group1
cd group1
echo 10G > memory.high
echo 10G > memory.max
echo $$ > cgroup.procs
mkfs.ext4 -F /dev/vdb
mount /dev/vdb /bdi1/

/* run fio to generate dirty pages */
fio -name test -filename=/bdi1/file -size=xxx -ioengine=libaio -bs=4K \
-iodepth=1 -rw=write -direct=0 --time_based -runtime=600 -invalidate=0

When fio size is 1G, the wb is in freerun state and dirty pages are only
written back when dirty inode is expired after 30 seconds.  When fio size
is 2G, the dirty pages keep being written back and bandwidth of fio is
limited.


This patch (of 8):

Similar to wb_dirty_limits which calculates dirty and thresh of wb,
wb_bg_dirty_limits calculates background dirty and background thresh of
wb.  With wb_bg_dirty_limits, we could remove repeated code in
wb_over_bg_thresh.

Link: https://lkml.kernel.org/r/20240514125254.142203-1-shikemeng@huaweicloud.com
Link: https://lkml.kernel.org/r/20240514125254.142203-2-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03 19:29:53 -07:00
Linus Torvalds
61307b7be4 The usual shower of singleton fixes and minor series all over MM,
documented (hopefully adequately) in the respective changelogs.  Notable
 series include:
 
 - Lucas Stach has provided some page-mapping
   cleanup/consolidation/maintainability work in the series "mm/treewide:
   Remove pXd_huge() API".
 
 - In the series "Allow migrate on protnone reference with
   MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
   MPOL_PREFERRED_MANY mode, yielding almost doubled performance in one
   test.
 
 - In their series "Memory allocation profiling" Kent Overstreet and
   Suren Baghdasaryan have contributed a means of determining (via
   /proc/allocinfo) whereabouts in the kernel memory is being allocated:
   number of calls and amount of memory.
 
 - Matthew Wilcox has provided the series "Various significant MM
   patches" which does a number of rather unrelated things, but in largely
   similar code sites.
 
 - In his series "mm: page_alloc: freelist migratetype hygiene" Johannes
   Weiner has fixed the page allocator's handling of migratetype requests,
   with resulting improvements in compaction efficiency.
 
 - In the series "make the hugetlb migration strategy consistent" Baolin
   Wang has fixed a hugetlb migration issue, which should improve hugetlb
   allocation reliability.
 
 - Liu Shixin has hit an I/O meltdown caused by readahead in a
   memory-tight memcg.  Addressed in the series "Fix I/O high when memory
   almost met memcg limit".
 
 - In the series "mm/filemap: optimize folio adding and splitting" Kairui
   Song has optimized pagecache insertion, yielding ~10% performance
   improvement in one test.
 
 - Baoquan He has cleaned up and consolidated the early zone
   initialization code in the series "mm/mm_init.c: refactor
   free_area_init_core()".
 
 - Baoquan has also redone some MM initializatio code in the series
   "mm/init: minor clean up and improvement".
 
 - MM helper cleanups from Christoph Hellwig in his series "remove
   follow_pfn".
 
 - More cleanups from Matthew Wilcox in the series "Various page->flags
   cleanups".
 
 - Vlastimil Babka has contributed maintainability improvements in the
   series "memcg_kmem hooks refactoring".
 
 - More folio conversions and cleanups in Matthew Wilcox's series
 
 	"Convert huge_zero_page to huge_zero_folio"
 	"khugepaged folio conversions"
 	"Remove page_idle and page_young wrappers"
 	"Use folio APIs in procfs"
 	"Clean up __folio_put()"
 	"Some cleanups for memory-failure"
 	"Remove page_mapping()"
 	"More folio compat code removal"
 
 - David Hildenbrand chipped in with "fs/proc/task_mmu: convert hugetlb
   functions to work on folis".
 
 - Code consolidation and cleanup work related to GUP's handling of
   hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".
 
 - Rick Edgecombe has developed some fixes to stack guard gaps in the
   series "Cover a guard gap corner case".
 
 - Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the series
   "mm/ksm: fix ksm exec support for prctl".
 
 - Baolin Wang has implemented NUMA balancing for multi-size THPs.  This
   is a simple first-cut implementation for now.  The series is "support
   multi-size THP numa balancing".
 
 - Cleanups to vma handling helper functions from Matthew Wilcox in the
   series "Unify vma_address and vma_pgoff_address".
 
 - Some selftests maintenance work from Dev Jain in the series
   "selftests/mm: mremap_test: Optimizations and style fixes".
 
 - Improvements to the swapping of multi-size THPs from Ryan Roberts in
   the series "Swap-out mTHP without splitting".
 
 - Kefeng Wang has significantly optimized the handling of arm64's
   permission page faults in the series
 
 	"arch/mm/fault: accelerate pagefault when badaccess"
 	"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"
 
 - GUP cleanups from David Hildenbrand in "mm/gup: consistently call it
   GUP-fast".
 
 - hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault path to
   use struct vm_fault".
 
 - selftests build fixes from John Hubbard in the series "Fix
   selftests/mm build without requiring "make headers"".
 
 - Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
   series "Improved Memory Tier Creation for CPUless NUMA Nodes".  Fixes
   the initialization code so that migration between different memory types
   works as intended.
 
 - David Hildenbrand has improved follow_pte() and fixed an errant driver
   in the series "mm: follow_pte() improvements and acrn follow_pte()
   fixes".
 
 - David also did some cleanup work on large folio mapcounts in his
   series "mm: mapcount for large folios + page_mapcount() cleanups".
 
 - Folio conversions in KSM in Alex Shi's series "transfer page to folio
   in KSM".
 
 - Barry Song has added some sysfs stats for monitoring multi-size THP's
   in the series "mm: add per-order mTHP alloc and swpout counters".
 
 - Some zswap cleanups from Yosry Ahmed in the series "zswap same-filled
   and limit checking cleanups".
 
 - Matthew Wilcox has been looking at buffer_head code and found the
   documentation to be lacking.  The series is "Improve buffer head
   documentation".
 
 - Multi-size THPs get more work, this time from Lance Yang.  His series
   "mm/madvise: enhance lazyfreeing with mTHP in madvise_free" optimizes
   the freeing of these things.
 
 - Kemeng Shi has added more userspace-visible writeback instrumentation
   in the series "Improve visibility of writeback".
 
 - Kemeng Shi then sent some maintenance work on top in the series "Fix
   and cleanups to page-writeback".
 
 - Matthew Wilcox reduces mmap_lock traffic in the anon vma code in the
   series "Improve anon_vma scalability for anon VMAs".  Intel's test bot
   reported an improbable 3x improvement in one test.
 
 - SeongJae Park adds some DAMON feature work in the series
 
 	"mm/damon: add a DAMOS filter type for page granularity access recheck"
 	"selftests/damon: add DAMOS quota goal test"
 
 - Also some maintenance work in the series
 
 	"mm/damon/paddr: simplify page level access re-check for pageout"
 	"mm/damon: misc fixes and improvements"
 
 - David Hildenbrand has disabled some known-to-fail selftests ni the
   series "selftests: mm: cow: flag vmsplice() hugetlb tests as XFAIL".
 
 - memcg metadata storage optimizations from Shakeel Butt in "memcg:
   reduce memory consumption by memcg stats".
 
 - DAX fixes and maintenance work from Vishal Verma in the series
   "dax/bus.c: Fixups for dax-bus locking".
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Merge tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull mm updates from Andrew Morton:
 "The usual shower of singleton fixes and minor series all over MM,
  documented (hopefully adequately) in the respective changelogs.
  Notable series include:

   - Lucas Stach has provided some page-mapping cleanup/consolidation/
     maintainability work in the series "mm/treewide: Remove pXd_huge()
     API".

   - In the series "Allow migrate on protnone reference with
     MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
     MPOL_PREFERRED_MANY mode, yielding almost doubled performance in
     one test.

   - In their series "Memory allocation profiling" Kent Overstreet and
     Suren Baghdasaryan have contributed a means of determining (via
     /proc/allocinfo) whereabouts in the kernel memory is being
     allocated: number of calls and amount of memory.

   - Matthew Wilcox has provided the series "Various significant MM
     patches" which does a number of rather unrelated things, but in
     largely similar code sites.

   - In his series "mm: page_alloc: freelist migratetype hygiene"
     Johannes Weiner has fixed the page allocator's handling of
     migratetype requests, with resulting improvements in compaction
     efficiency.

   - In the series "make the hugetlb migration strategy consistent"
     Baolin Wang has fixed a hugetlb migration issue, which should
     improve hugetlb allocation reliability.

   - Liu Shixin has hit an I/O meltdown caused by readahead in a
     memory-tight memcg. Addressed in the series "Fix I/O high when
     memory almost met memcg limit".

   - In the series "mm/filemap: optimize folio adding and splitting"
     Kairui Song has optimized pagecache insertion, yielding ~10%
     performance improvement in one test.

   - Baoquan He has cleaned up and consolidated the early zone
     initialization code in the series "mm/mm_init.c: refactor
     free_area_init_core()".

   - Baoquan has also redone some MM initializatio code in the series
     "mm/init: minor clean up and improvement".

   - MM helper cleanups from Christoph Hellwig in his series "remove
     follow_pfn".

   - More cleanups from Matthew Wilcox in the series "Various
     page->flags cleanups".

   - Vlastimil Babka has contributed maintainability improvements in the
     series "memcg_kmem hooks refactoring".

   - More folio conversions and cleanups in Matthew Wilcox's series:
	"Convert huge_zero_page to huge_zero_folio"
	"khugepaged folio conversions"
	"Remove page_idle and page_young wrappers"
	"Use folio APIs in procfs"
	"Clean up __folio_put()"
	"Some cleanups for memory-failure"
	"Remove page_mapping()"
	"More folio compat code removal"

   - David Hildenbrand chipped in with "fs/proc/task_mmu: convert
     hugetlb functions to work on folis".

   - Code consolidation and cleanup work related to GUP's handling of
     hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".

   - Rick Edgecombe has developed some fixes to stack guard gaps in the
     series "Cover a guard gap corner case".

   - Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the
     series "mm/ksm: fix ksm exec support for prctl".

   - Baolin Wang has implemented NUMA balancing for multi-size THPs.
     This is a simple first-cut implementation for now. The series is
     "support multi-size THP numa balancing".

   - Cleanups to vma handling helper functions from Matthew Wilcox in
     the series "Unify vma_address and vma_pgoff_address".

   - Some selftests maintenance work from Dev Jain in the series
     "selftests/mm: mremap_test: Optimizations and style fixes".

   - Improvements to the swapping of multi-size THPs from Ryan Roberts
     in the series "Swap-out mTHP without splitting".

   - Kefeng Wang has significantly optimized the handling of arm64's
     permission page faults in the series
	"arch/mm/fault: accelerate pagefault when badaccess"
	"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"

   - GUP cleanups from David Hildenbrand in "mm/gup: consistently call
     it GUP-fast".

   - hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault
     path to use struct vm_fault".

   - selftests build fixes from John Hubbard in the series "Fix
     selftests/mm build without requiring "make headers"".

   - Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
     series "Improved Memory Tier Creation for CPUless NUMA Nodes".
     Fixes the initialization code so that migration between different
     memory types works as intended.

   - David Hildenbrand has improved follow_pte() and fixed an errant
     driver in the series "mm: follow_pte() improvements and acrn
     follow_pte() fixes".

   - David also did some cleanup work on large folio mapcounts in his
     series "mm: mapcount for large folios + page_mapcount() cleanups".

   - Folio conversions in KSM in Alex Shi's series "transfer page to
     folio in KSM".

   - Barry Song has added some sysfs stats for monitoring multi-size
     THP's in the series "mm: add per-order mTHP alloc and swpout
     counters".

   - Some zswap cleanups from Yosry Ahmed in the series "zswap
     same-filled and limit checking cleanups".

   - Matthew Wilcox has been looking at buffer_head code and found the
     documentation to be lacking. The series is "Improve buffer head
     documentation".

   - Multi-size THPs get more work, this time from Lance Yang. His
     series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free"
     optimizes the freeing of these things.

   - Kemeng Shi has added more userspace-visible writeback
     instrumentation in the series "Improve visibility of writeback".

   - Kemeng Shi then sent some maintenance work on top in the series
     "Fix and cleanups to page-writeback".

   - Matthew Wilcox reduces mmap_lock traffic in the anon vma code in
     the series "Improve anon_vma scalability for anon VMAs". Intel's
     test bot reported an improbable 3x improvement in one test.

   - SeongJae Park adds some DAMON feature work in the series
	"mm/damon: add a DAMOS filter type for page granularity access recheck"
	"selftests/damon: add DAMOS quota goal test"

   - Also some maintenance work in the series
	"mm/damon/paddr: simplify page level access re-check for pageout"
	"mm/damon: misc fixes and improvements"

   - David Hildenbrand has disabled some known-to-fail selftests ni the
     series "selftests: mm: cow: flag vmsplice() hugetlb tests as
     XFAIL".

   - memcg metadata storage optimizations from Shakeel Butt in "memcg:
     reduce memory consumption by memcg stats".

   - DAX fixes and maintenance work from Vishal Verma in the series
     "dax/bus.c: Fixups for dax-bus locking""

* tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits)
  memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order
  selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime
  mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp
  mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault
  selftests: cgroup: add tests to verify the zswap writeback path
  mm: memcg: make alloc_mem_cgroup_per_node_info() return bool
  mm/damon/core: fix return value from damos_wmark_metric_value
  mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED
  selftests: cgroup: remove redundant enabling of memory controller
  Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree
  Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT
  Docs/mm/damon/design: use a list for supported filters
  Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command
  Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file
  selftests/damon: classify tests for functionalities and regressions
  selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None'
  selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts
  selftests/damon/_damon_sysfs: check errors from nr_schemes file reads
  mm/damon/core: initialize ->esz_bp from damos_quota_init_priv()
  selftests/damon: add a test for DAMOS quota goal
  ...
2024-05-19 09:21:03 -07:00
Kemeng Shi
dc6e0ae5b1 mm: remove stale comment __folio_mark_dirty
The __folio_mark_dirty will not mark inode dirty any longer.  Remove the
stale comment of it.

Link: https://lkml.kernel.org/r/20240425131724.36778-5-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Howard Cochran <hcochran@kernelspring.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05 17:53:53 -07:00
Kemeng Shi
3b3e412e5f mm: call __wb_calc_thresh instead of wb_calc_thresh in wb_over_bg_thresh
Call __wb_calc_thresh to calculate wb bg_thresh of gdtc in
wb_over_bg_thresh to remove unnecessary wrap in wb_calc_thresh.

Link: https://lkml.kernel.org/r/20240425131724.36778-4-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Howard Cochran <hcochran@kernelspring.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05 17:53:52 -07:00
Kemeng Shi
fabd2e42bc mm: correct calculation of wb's bg_thresh in cgroup domain
wb_calc_thresh() is calculating wb's share of bg_thresh in the global
domain.  However in case of cgroup writeback this is not the right
thing to do.  Consider the following domain hierarchy:

                global domain (> 20G)
                /                 \
          cgroup1 (10G)     cgroup2 (10G)
                |                 |
bdi            wb1               wb2

and assume wb1 and wb2 have the same bandwidth and the background
threshold is set at 10%.  The bg_thresh of cgroup1 and cgroup2 is going
to be 1G.  Now because wb_calc_thresh(mdtc->wb, mdtc->bg_thresh)
calculates per-wb threshold in the global domain as (wb bandwidth) /
(domain bandwidth) it returns bg_thresh for wb1 as 0.5G although it has
nobody to compete against in cgroup1.

Fix the problem by calculating wb's share of bg_thresh in the cgroup
domain.

Test as following:
/* make it easier to observe the issue */
echo 300000 > /proc/sys/vm/dirty_expire_centisecs
echo 100 > /proc/sys/vm/dirty_writeback_centisecs

/* run fio in wb1 */
cd /sys/fs/cgroup
echo "+memory +io" > cgroup.subtree_control
mkdir group1
cd group1
echo 10G > memory.high
echo 10G > memory.max
echo $$ > cgroup.procs
mkfs.ext4 -F /dev/vdb
mount /dev/vdb /bdi1/
fio -name test -filename=/bdi1/file -size=600M -ioengine=libaio -bs=4K \
-iodepth=1 -rw=write -direct=0 --time_based -runtime=600 -invalidate=0

/* run fio in wb2 with a new shell */
cd /sys/fs/cgroup
mkdir group2
cd group2
echo 10G > memory.high
echo 10G > memory.max
echo $$ > cgroup.procs
mkfs.ext4 -F /dev/vdc
mount /dev/vdc /bdi2/
fio -name test -filename=/bdi2/file -size=600M -ioengine=libaio -bs=4K \
-iodepth=1 -rw=write -direct=0 --time_based -runtime=600 -invalidate=0

Before fix, the wrttien pages of wb1 and wb2 reported from
toos/writeback/wb_monitor.py keep growing. After fix, rare written pages
are accumulated.
There is no obvious change in fio result.

[jack@suse.cz: changelog rewording]
Link: https://lkml.kernel.org/r/20240425131724.36778-3-shikemeng@huaweicloud.com
Fixes: 74d3694433 ("writeback: Fix performance regression in wb_over_bg_thresh()")
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Howard Cochran <hcochran@kernelspring.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05 17:53:52 -07:00
Kemeng Shi
13fc441284 mm: enable __wb_calc_thresh to calculate dirty background threshold
Patch series "Fix and cleanups to page-writeback", v2.

This series contains some random cleanups and a fix to correct calculation
of wb's bg_thresh in cgroup domain.  More details can be found respective
patches.


This patch (of 4):

Originally, __wb_calc_thresh always calculate wb's share of dirty
throttling threshold.  By getting thresh of wb_domain from caller,
__wb_calc_thresh could be used for both dirty throttling and dirty
background threshold.

This is a preparation to correct threshold calculation of wb in cgroup.

Link: https://lkml.kernel.org/r/20240425131724.36778-1-shikemeng@huaweicloud.com
Link: https://lkml.kernel.org/r/20240425131724.36778-2-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Howard Cochran <hcochran@kernelspring.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05 17:53:52 -07:00
Kemeng Shi
826881a7f6 writeback: rename nr_reclaimable to nr_dirty in balance_dirty_pages
Commit 8d92890bd6 ("mm/writeback: discard NR_UNSTABLE_NFS, use
NR_WRITEBACK instead") removed NR_UNSTABLE_NFS and nr_reclaimable only
contains dirty page now.  Rename nr_reclaimable to nr_dirty properly.

Link: https://lkml.kernel.org/r/20240423034643.141219-6-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Brian Foster <bfoster@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: SeongJae Park <sj@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05 17:53:52 -07:00
Kemeng Shi
4b5bbc39d7 writeback: support retrieving per group debug writeback stats of bdi
Add /sys/kernel/debug/bdi/xxx/wb_stats to show per group writeback stats
of bdi.

Following domain hierarchy is tested:
                global domain (320G)
                /                 \
        cgroup domain1(10G)     cgroup domain2(10G)
                |                 |
bdi            wb1               wb2

/* per wb writeback info of bdi is collected */
cat wb_stats
WbCgIno:                    1
WbWriteback:                0 kB
WbReclaimable:              0 kB
WbDirtyThresh:              0 kB
WbDirtied:                  0 kB
WbWritten:                  0 kB
WbWriteBandwidth:      102400 kBps
b_dirty:                    0
b_io:                       0
b_more_io:                  0
b_dirty_time:               0
state:                      1

WbCgIno:                 4091
WbWriteback:             1792 kB
WbReclaimable:         820512 kB
WbDirtyThresh:        6004692 kB
WbDirtied:            1820448 kB
WbWritten:             999488 kB
WbWriteBandwidth:      169020 kBps
b_dirty:                    0
b_io:                       0
b_more_io:                  1
b_dirty_time:               0
state:                      5

WbCgIno:                 4131
WbWriteback:             1120 kB
WbReclaimable:         820064 kB
WbDirtyThresh:        6004728 kB
WbDirtied:            1822688 kB
WbWritten:            1002400 kB
WbWriteBandwidth:      153520 kBps
b_dirty:                    0
b_io:                       0
b_more_io:                  1
b_dirty_time:               0
state:                      5

[shikemeng@huaweicloud.com: fix build problems]
  Link: https://lkml.kernel.org/r/20240423034643.141219-4-shikemeng@huaweicloud.com
Link: https://lkml.kernel.org/r/20240423034643.141219-3-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Brian Foster <bfoster@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: SeongJae Park <sj@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05 17:53:51 -07:00
Matthew Wilcox (Oracle)
3d84d89792 doc: improve the description of __folio_mark_dirty
Patch series "Improve buffer head documentation", v3.

Turn buffer head documentation into its own document, and make many
general improvements to the docs.  Obviously there is much more that could
be done.  Tested with make htmldocs.


This patch (of 8):

I've learned why it's safe to call __folio_mark_dirty() from
mark_buffer_dirty() without holding the folio lock, so update the
description to explain why.

Link: https://lkml.kernel.org/r/20240416031754.4076917-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20240416031754.4076917-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05 17:53:39 -07:00
David Howells
5a550a0c60 mm: Export writeback_iter()
Export writeback_iter() so that it can be used by netfslib as a module.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: Matthew Wilcox (Oracle) <willy@infradead.org>
cc: Christoph Hellwig <hch@lst.de>
cc: linux-mm@kvack.org
2024-05-01 18:07:35 +01:00
Joel Granados
7998df0b64 memory: remove the now superfluous sentinel element from ctl_table array
This commit comes at the tail end of a greater effort to remove the empty
elements at the end of the ctl_table arrays (sentinels) which will reduce
the overall build time size of the kernel and run time memory bloat by ~64
bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)

Remove sentinel from all files under mm/ that register a sysctl table.

Link: https://lkml.kernel.org/r/20240328-jag-sysctl_remset_misc-v1-1-47c1463b3af2@samsung.com
Signed-off-by: Joel Granados <j.granados@samsung.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25 20:56:32 -07:00
Matthew Wilcox (Oracle)
c44ed5b759 writeback: remove a use of write_cache_pages() from do_writepages()
Use the new writeback_iter() directly instead of indirecting through a
callback.

[hch@lst.de: ported to the while based iter style]
Link: https://lkml.kernel.org/r/20240215063649.2164017-15-hch@lst.de
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:38 -08:00
Christoph Hellwig
cdc150b575 writeback: add a writeback iterator
Refactor the code left in write_cache_pages into an iterator that the file
system can call to get the next folio for a writeback operation:

	struct folio *folio = NULL;

	while ((folio = writeback_iter(mapping, wbc, folio, &error))) {
		error = <do per-folio writeback>;
	}

The twist here is that the error value is passed by reference, so that the
iterator can restore it when breaking out of the loop.

Handling of the magic AOP_WRITEPAGE_ACTIVATE value stays outside the
iterator and needs is just kept in the write_cache_pages legacy wrapper. 
in preparation for eventually killing it off.

Heavily based on a for_each* based iterator from Matthew Wilcox.

Link: https://lkml.kernel.org/r/20240215063649.2164017-14-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:37 -08:00
Matthew Wilcox (Oracle)
a2cbc13638 writeback: move the folio_prepare_writeback loop out of write_cache_pages()
Move the loop for should-we-write-this-folio to writeback_get_folio.

[hch@lst.de: fold loop into existing helper instead of a separate one per Jan]
Link: https://lkml.kernel.org/r/20240215063649.2164017-13-hch@lst.de
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:37 -08:00
Matthew Wilcox (Oracle)
e6d0ab87c8 writeback: use the folio_batch queue iterator
Instead of keeping our own local iterator variable, use the one just added
to folio_batch.

Link: https://lkml.kernel.org/r/20240215063649.2164017-12-hch@lst.de
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:37 -08:00
Matthew Wilcox (Oracle)
807d1fe360 writeback: simplify the loops in write_cache_pages()
Collapse the two nested loops into one.  This is needed as a step towards
turning this into an iterator.

Note that this drops the "index <= end" check in the previous outer loop
and just relies on filemap_get_folios_tag() to return 0 entries when index
> end.  This actually has a subtle implication when end == -1 because then
the returned index will be -1 as well and thus if there is page present on
index -1, we could be looping indefinitely.  But as the comment in
filemap_get_folios_tag documents this as already broken anyway we should
not worry about it here either.  The fix for that would probably a change
to the filemap_get_folios_tag() calling convention.

[hch@lst.de: update the commit log per Jan]
Link: https://lkml.kernel.org/r/20240215063649.2164017-10-hch@lst.de
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:36 -08:00
Matthew Wilcox (Oracle)
751e0d559c writeback: factor writeback_get_batch() out of write_cache_pages()
This simple helper will be the basis of the writeback iterator.  To make
this work, we need to remember the current index and end positions in
writeback_control.

[hch@lst.de: heavily rebased, add helpers to get the tag and end index, don't keep the end index in struct writeback_control]
Link: https://lkml.kernel.org/r/20240215063649.2164017-9-hch@lst.de
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:36 -08:00
Matthew Wilcox (Oracle)
b1793929b7 writeback: factor folio_prepare_writeback() out of write_cache_pages()
Reduce write_cache_pages() by about 30 lines; much of it is commentary,
but it all bundles nicely into an obvious function.

[hch@lst.de: rename should_writeback_folio to folio_prepare_writeback per Jan]
Link: https://lkml.kernel.org/r/20240215063649.2164017-8-hch@lst.de
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:36 -08:00
Christoph Hellwig
f946e0d22e writeback: rework the loop termination condition in write_cache_pages
Rework the way we deal with the cleanup after the writepage call.

First handle the magic AOP_WRITEPAGE_ACTIVATE separately from real error
returns to get it out of the way of the actual error handling path.

The split the handling on intgrity vs non-integrity branches first, and
return early using a goto for the non-ingegrity early loop condition to
remove the need for the done and done_index local variables, and for
assigning the error to ret when we can just return error directly.

Link: https://lkml.kernel.org/r/20240215063649.2164017-7-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:36 -08:00
Christoph Hellwig
5d899d43ed writeback: only update ->writeback_index for range_cyclic writeback
mapping->writeback_index is only [1] used as the starting point for
range_cyclic writeback, so there is no point in updating it for other
types of writeback.

[1] except for btrfs_defrag_file which does really odd things with
mapping->writeback_index.  But btrfs doesn't use write_cache_pages at all,
so this isn't relevant here.

Link: https://lkml.kernel.org/r/20240215063649.2164017-6-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:36 -08:00
Christoph Hellwig
9810325854 writeback: also update wbc->nr_to_write on writeback failure
When exiting write_cache_pages early due to a non-integrity write failure,
wbc->nr_to_write currently doesn't account for the folio we just failed to
write.  This doesn't matter because the callers always ingore the value on
a failure, but moving the update to common code will allow to simplify the
code, so do it.

Link: https://lkml.kernel.org/r/20240215063649.2164017-5-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:35 -08:00
Christoph Hellwig
a02829f011 writeback: fix done_index when hitting the wbc->nr_to_write
When write_cache_pages finishes writing out a folio, it fails to update
done_index to account for the number of pages in the folio just written. 
That means when range_cyclic writeback is restarted, it will be restarted
at this folio instead of after it as it should.  Fix that by updating
done_index before breaking out of the loop.

Link: https://lkml.kernel.org/r/20240215063649.2164017-4-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:35 -08:00
Christoph Hellwig
6768907eb2 writeback: don't call mapping_set_error on AOP_WRITEPAGE_ACTIVATE
Patch series "convert write_cache_pages() to an iterator", v8.

This is an evolution of the series Matthew Wilcox originally sent in June
2023, which has changed quite a bit since and now has a while based
iterator.


This patch (of 14):

mapping_set_error should only be called on 0 returns (which it ignores) or
a negative error code.

writepage_cb ends up being able to call writepage_cb on the magic
AOP_WRITEPAGE_ACTIVATE return value from ->writepage which means success
but the caller needs to unlock the page.  Ignore that and just call
mapping_set_error on negative errors.

(no fixes tag as this goes back more than 20 years over various renames
and refactors so I've given up chasing down the original introduction)

Link: https://lkml.kernel.org/r/20240215063649.2164017-1-hch@lst.de
Link: https://lkml.kernel.org/r/20240215063649.2164017-2-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:35 -08:00
Linus Torvalds
a5b6244cf8 block-6.8-2024-02-10
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Merge tag 'block-6.8-2024-02-10' of git://git.kernel.dk/linux

Pull block fixes from Jens Axboe:

 - NVMe pull request via Keith:
     - Update a potentially stale firmware attribute (Maurizio)
     - Fixes for the recent verbose error logging (Keith, Chaitanya)
     - Protection information payload size fix for passthrough (Francis)

 - Fix for a queue freezing issue in virtblk (Yi)

 - blk-iocost underflow fix (Tejun)

 - blk-wbt task detection fix (Jan)

* tag 'block-6.8-2024-02-10' of git://git.kernel.dk/linux:
  virtio-blk: Ensure no requests in virtqueues before deleting vqs.
  blk-iocost: Fix an UBSAN shift-out-of-bounds warning
  nvme: use ns->head->pi_size instead of t10_pi_tuple structure size
  nvme-core: fix comment to reflect right functions
  nvme: move passthrough logging attribute to head
  blk-wbt: Fix detection of dirty-throttled tasks
  nvme-host: fix the updating of the firmware version
2024-02-10 08:02:48 -08:00
Jan Kara
f814bdda77 blk-wbt: Fix detection of dirty-throttled tasks
The detection of dirty-throttled tasks in blk-wbt has been subtly broken
since its beginning in 2016. Namely if we are doing cgroup writeback and
the throttled task is not in the root cgroup, balance_dirty_pages() will
set dirty_sleep for the non-root bdi_writeback structure. However
blk-wbt checks dirty_sleep only in the root cgroup bdi_writeback
structure. Thus detection of recently throttled tasks is not working in
this case (we noticed this when we switched to cgroup v2 and suddently
writeback was slow).

Since blk-wbt has no easy way to get to proper bdi_writeback and
furthermore its intention has always been to work on the whole device
rather than on individual cgroups, just move the dirty_sleep timestamp
from bdi_writeback to backing_dev_info. That fixes the checking for
recently throttled task and saves memory for everybody as a bonus.

CC: stable@vger.kernel.org
Fixes: b57d74aff9 ("writeback: track if we're sleeping on progress in balance_dirty_pages()")
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240123175826.21452-1-jack@suse.cz
[axboe: fixup indentation errors]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-06 09:44:03 -07:00
Zach O'Keefe
9319b64790 mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again
(struct dirty_throttle_control *)->thresh is an unsigned long, but is
passed as the u32 divisor argument to div_u64().  On architectures where
unsigned long is 64 bytes, the argument will be implicitly truncated.

Use div64_u64() instead of div_u64() so that the value used in the "is
this a safe division" check is the same as the divisor.

Also, remove redundant cast of the numerator to u64, as that should happen
implicitly.

This would be difficult to exploit in memcg domain, given the ratio-based
arithmetic domain_drity_limits() uses, but is much easier in global
writeback domain with a BDI_CAP_STRICTLIMIT-backing device, using e.g. 
vm.dirty_bytes=(1<<32)*PAGE_SIZE so that dtc->thresh == (1<<32)

Link: https://lkml.kernel.org/r/20240118181954.1415197-1-zokeefe@google.com
Fixes: f6789593d5 ("mm/page-writeback.c: fix divide by zero in bdi_dirty_limits()")
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Cc: Maxim Patlasov <MPatlasov@parallels.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-01-25 23:52:20 -08:00
Linus Torvalds
fb46e22a9e Many singleton patches against the MM code. The patch series which
are included in this merge do the following:
 
 - Peng Zhang has done some mapletree maintainance work in the
   series
 
 	"maple_tree: add mt_free_one() and mt_attr() helpers"
 	"Some cleanups of maple tree"
 
 - In the series "mm: use memmap_on_memory semantics for dax/kmem"
   Vishal Verma has altered the interworking between memory-hotplug
   and dax/kmem so that newly added 'device memory' can more easily
   have its memmap placed within that newly added memory.
 
 - Matthew Wilcox continues folio-related work (including a few
   fixes) in the patch series
 
 	"Add folio_zero_tail() and folio_fill_tail()"
 	"Make folio_start_writeback return void"
 	"Fix fault handler's handling of poisoned tail pages"
 	"Convert aops->error_remove_page to ->error_remove_folio"
 	"Finish two folio conversions"
 	"More swap folio conversions"
 
 - Kefeng Wang has also contributed folio-related work in the series
 
 	"mm: cleanup and use more folio in page fault"
 
 - Jim Cromie has improved the kmemleak reporting output in the
   series "tweak kmemleak report format".
 
 - In the series "stackdepot: allow evicting stack traces" Andrey
   Konovalov to permits clients (in this case KASAN) to cause
   eviction of no longer needed stack traces.
 
 - Charan Teja Kalla has fixed some accounting issues in the page
   allocator's atomic reserve calculations in the series "mm:
   page_alloc: fixes for high atomic reserve caluculations".
 
 - Dmitry Rokosov has added to the samples/ dorectory some sample
   code for a userspace memcg event listener application.  See the
   series "samples: introduce cgroup events listeners".
 
 - Some mapletree maintanance work from Liam Howlett in the series
   "maple_tree: iterator state changes".
 
 - Nhat Pham has improved zswap's approach to writeback in the
   series "workload-specific and memory pressure-driven zswap
   writeback".
 
 - DAMON/DAMOS feature and maintenance work from SeongJae Park in
   the series
 
 	"mm/damon: let users feed and tame/auto-tune DAMOS"
 	"selftests/damon: add Python-written DAMON functionality tests"
 	"mm/damon: misc updates for 6.8"
 
 - Yosry Ahmed has improved memcg's stats flushing in the series
   "mm: memcg: subtree stats flushing and thresholds".
 
 - In the series "Multi-size THP for anonymous memory" Ryan Roberts
   has added a runtime opt-in feature to transparent hugepages which
   improves performance by allocating larger chunks of memory during
   anonymous page faults.
 
 - Matthew Wilcox has also contributed some cleanup and maintenance
   work against eh buffer_head code int he series "More buffer_head
   cleanups".
 
 - Suren Baghdasaryan has done work on Andrea Arcangeli's series
   "userfaultfd move option".  UFFDIO_MOVE permits userspace heap
   compaction algorithms to move userspace's pages around rather than
   UFFDIO_COPY'a alloc/copy/free.
 
 - Stefan Roesch has developed a "KSM Advisor", in the series
   "mm/ksm: Add ksm advisor".  This is a governor which tunes KSM's
   scanning aggressiveness in response to userspace's current needs.
 
 - Chengming Zhou has optimized zswap's temporary working memory
   use in the series "mm/zswap: dstmem reuse optimizations and
   cleanups".
 
 - Matthew Wilcox has performed some maintenance work on the
   writeback code, both code and within filesystems.  The series is
   "Clean up the writeback paths".
 
 - Andrey Konovalov has optimized KASAN's handling of alloc and
   free stack traces for secondary-level allocators, in the series
   "kasan: save mempool stack traces".
 
 - Andrey also performed some KASAN maintenance work in the series
   "kasan: assorted clean-ups".
 
 - David Hildenbrand has gone to town on the rmap code.  Cleanups,
   more pte batching, folio conversions and more.  See the series
   "mm/rmap: interface overhaul".
 
 - Kinsey Ho has contributed some maintenance work on the MGLRU
   code in the series "mm/mglru: Kconfig cleanup".
 
 - Matthew Wilcox has contributed lruvec page accounting code
   cleanups in the series "Remove some lruvec page accounting
   functions".
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Merge tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:
 "Many singleton patches against the MM code. The patch series which are
  included in this merge do the following:

   - Peng Zhang has done some mapletree maintainance work in the series

	'maple_tree: add mt_free_one() and mt_attr() helpers'
	'Some cleanups of maple tree'

   - In the series 'mm: use memmap_on_memory semantics for dax/kmem'
     Vishal Verma has altered the interworking between memory-hotplug
     and dax/kmem so that newly added 'device memory' can more easily
     have its memmap placed within that newly added memory.

   - Matthew Wilcox continues folio-related work (including a few fixes)
     in the patch series

	'Add folio_zero_tail() and folio_fill_tail()'
	'Make folio_start_writeback return void'
	'Fix fault handler's handling of poisoned tail pages'
	'Convert aops->error_remove_page to ->error_remove_folio'
	'Finish two folio conversions'
	'More swap folio conversions'

   - Kefeng Wang has also contributed folio-related work in the series

	'mm: cleanup and use more folio in page fault'

   - Jim Cromie has improved the kmemleak reporting output in the series
     'tweak kmemleak report format'.

   - In the series 'stackdepot: allow evicting stack traces' Andrey
     Konovalov to permits clients (in this case KASAN) to cause eviction
     of no longer needed stack traces.

   - Charan Teja Kalla has fixed some accounting issues in the page
     allocator's atomic reserve calculations in the series 'mm:
     page_alloc: fixes for high atomic reserve caluculations'.

   - Dmitry Rokosov has added to the samples/ dorectory some sample code
     for a userspace memcg event listener application. See the series
     'samples: introduce cgroup events listeners'.

   - Some mapletree maintanance work from Liam Howlett in the series
     'maple_tree: iterator state changes'.

   - Nhat Pham has improved zswap's approach to writeback in the series
     'workload-specific and memory pressure-driven zswap writeback'.

   - DAMON/DAMOS feature and maintenance work from SeongJae Park in the
     series

	'mm/damon: let users feed and tame/auto-tune DAMOS'
	'selftests/damon: add Python-written DAMON functionality tests'
	'mm/damon: misc updates for 6.8'

   - Yosry Ahmed has improved memcg's stats flushing in the series 'mm:
     memcg: subtree stats flushing and thresholds'.

   - In the series 'Multi-size THP for anonymous memory' Ryan Roberts
     has added a runtime opt-in feature to transparent hugepages which
     improves performance by allocating larger chunks of memory during
     anonymous page faults.

   - Matthew Wilcox has also contributed some cleanup and maintenance
     work against eh buffer_head code int he series 'More buffer_head
     cleanups'.

   - Suren Baghdasaryan has done work on Andrea Arcangeli's series
     'userfaultfd move option'. UFFDIO_MOVE permits userspace heap
     compaction algorithms to move userspace's pages around rather than
     UFFDIO_COPY'a alloc/copy/free.

   - Stefan Roesch has developed a 'KSM Advisor', in the series 'mm/ksm:
     Add ksm advisor'. This is a governor which tunes KSM's scanning
     aggressiveness in response to userspace's current needs.

   - Chengming Zhou has optimized zswap's temporary working memory use
     in the series 'mm/zswap: dstmem reuse optimizations and cleanups'.

   - Matthew Wilcox has performed some maintenance work on the writeback
     code, both code and within filesystems. The series is 'Clean up the
     writeback paths'.

   - Andrey Konovalov has optimized KASAN's handling of alloc and free
     stack traces for secondary-level allocators, in the series 'kasan:
     save mempool stack traces'.

   - Andrey also performed some KASAN maintenance work in the series
     'kasan: assorted clean-ups'.

   - David Hildenbrand has gone to town on the rmap code. Cleanups, more
     pte batching, folio conversions and more. See the series 'mm/rmap:
     interface overhaul'.

   - Kinsey Ho has contributed some maintenance work on the MGLRU code
     in the series 'mm/mglru: Kconfig cleanup'.

   - Matthew Wilcox has contributed lruvec page accounting code cleanups
     in the series 'Remove some lruvec page accounting functions'"

* tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (361 commits)
  mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER
  mm, treewide: introduce NR_PAGE_ORDERS
  selftests/mm: add separate UFFDIO_MOVE test for PMD splitting
  selftests/mm: skip test if application doesn't has root privileges
  selftests/mm: conform test to TAP format output
  selftests: mm: hugepage-mmap: conform to TAP format output
  selftests/mm: gup_test: conform test to TAP format output
  mm/selftests: hugepage-mremap: conform test to TAP format output
  mm/vmstat: move pgdemote_* out of CONFIG_NUMA_BALANCING
  mm: zsmalloc: return -ENOSPC rather than -EINVAL in zs_malloc while size is too large
  mm/memcontrol: remove __mod_lruvec_page_state()
  mm/khugepaged: use a folio more in collapse_file()
  slub: use a folio in __kmalloc_large_node
  slub: use folio APIs in free_large_kmalloc()
  slub: use alloc_pages_node() in alloc_slab_page()
  mm: remove inc/dec lruvec page state functions
  mm: ratelimit stat flush from workingset shrinker
  kasan: stop leaking stack trace handles
  mm/mglru: remove CONFIG_TRANSPARENT_HUGEPAGE
  mm/mglru: add dummy pmd_dirty()
  ...
2024-01-09 11:18:47 -08:00
Jingbo Xu
fa151a39a6 mm: fix arithmetic for max_prop_frac when setting max_ratio
Since now bdi->max_ratio is part per million, fix the wrong arithmetic for
max_prop_frac when setting max_ratio.  Otherwise the miscalculated
max_prop_frac will affect the incrementing of writeout completion count
when max_ratio is not 100%.

Link: https://lkml.kernel.org/r/20231219142508.86265-3-jefflexu@linux.alibaba.com
Fixes: efc3e6ad53 ("mm: split off __bdi_set_max_ratio() function")
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Stefan Roesch <shr@devkernel.io>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29 11:06:47 -08:00
Jingbo Xu
e0646b7590 mm: fix arithmetic for bdi min_ratio
Since now bdi->min_ratio is part per million, fix the wrong arithmetic. 
Otherwise it will fail with -EINVAL when setting a reasonable min_ratio,
as it tries to set min_ratio to (min_ratio * BDI_RATIO_SCALE) in
percentage unit, which exceeds 100% anyway.

    # cat /sys/class/bdi/253\:0/min_ratio
    0
    # cat /sys/class/bdi/253\:0/max_ratio
    100
    # echo 1 > /sys/class/bdi/253\:0/min_ratio
    -bash: echo: write error: Invalid argument

Link: https://lkml.kernel.org/r/20231219142508.86265-2-jefflexu@linux.alibaba.com
Fixes: 8021fb3232 ("mm: split off __bdi_set_min_ratio() function")
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reported-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Stefan Roesch <shr@devkernel.io>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29 11:06:47 -08:00
Matthew Wilcox (Oracle)
b5612c3686 mm: return void from folio_start_writeback() and related functions
Nobody now checks the return value from any of these functions, so
add an assertion at the beginning of the function and return void.

Link: https://lkml.kernel.org/r/20231108204605.745109-5-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Steve French <sfrench@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10 16:51:37 -08:00
Christoph Hellwig
762321dab9 filemap: add a per-mapping stable writes flag
folio_wait_stable waits for writeback to finish before modifying the
contents of a folio again, e.g. to support check summing of the data
in the block integrity code.

Currently this behavior is controlled by the SB_I_STABLE_WRITES flag
on the super_block, which means it is uniform for the entire file system.
This is wrong for the block device pseudofs which is shared by all
block devices, or file systems that can use multiple devices like XFS
witht the RT subvolume or btrfs (although btrfs currently reimplements
folio_wait_stable anyway).

Add a per-address_space AS_STABLE_WRITES flag to control the behavior
in a more fine grained way.  The existing SB_I_STABLE_WRITES is kept
to initialize AS_STABLE_WRITES to the existing default which covers
most cases.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231025141020.192413-2-hch@lst.de
Tested-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-11-20 15:05:18 +01:00
Matthew Wilcox (Oracle)
2580d55458 mm: use folio_xor_flags_has_waiters() in folio_end_writeback()
Match how folio_unlock() works by combining the test for PG_waiters with
the clearing of PG_writeback.  This should have a small performance win,
and removes the last user of folio_wake().

Link: https://lkml.kernel.org/r/20231004165317.1061855-18-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-18 14:34:17 -07:00
Matthew Wilcox (Oracle)
7d0795d098 mm: make __end_folio_writeback() return void
Rather than check the result of test-and-clear, just check that we have
the writeback bit set at the start.  This wouldn't catch every case, but
it's good enough (and enables the next patch).

Link: https://lkml.kernel.org/r/20231004165317.1061855-17-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-18 14:34:17 -07:00
Jianguo Bao
ab428b4c45 mm/writeback: update filemap_dirty_folio() comment
Change to use new address space operation dirty_folio().

Link: https://lkml.kernel.org/r/20230917-trycontrib1-v1-1-db22630b8839@gmail.com
Fixes: 6f31a5a261 ("fs: Add aops->dirty_folio")
Signed-off-by: Jianguo Bau <roidinev@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-04 10:32:32 -07:00
Christoph Hellwig
ed2da9246f mm: remove folio_account_redirty
Fold folio_account_redirty into folio_redirty_for_writepage now
that all other users except for the also unused account_page_redirty
wrapper are gone.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:16 +02:00
Matthew Wilcox (Oracle)
8344a3d44b writeback: account the number of pages written back
nr_to_write is a count of pages, so we need to decrease it by the number
of pages in the folio we just wrote, not by 1.  Most callers specify
either LONG_MAX or 1, so are unaffected, but writeback_sb_inodes() might
end up writing 512x as many pages as it asked for.

Dave added:

: XFS is the only filesystem this would affect, right?  AFAIA, nothing
: else enables large folios and uses writeback through
: write_cache_pages() at this point...
: 
: In which case, I'd be surprised if much difference, if any, gets
: noticed by anyone.

Link: https://lkml.kernel.org/r/20230628185548.981888-1-willy@infradead.org
Fixes: 793917d997 ("mm/readahead: Add large folio readahead")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-07-08 09:29:30 -07:00