Commit Graph

467 Commits

Author SHA1 Message Date
zhenwei pi 67f22ba775 mm/memory-failure: disable unpoison once hw error happens
Currently unpoison_memory(unsigned long pfn) is designed for soft
poison(hwpoison-inject) only.  Since 17fae1294a, the KPTE gets cleared
on a x86 platform once hardware memory corrupts.

Unpoisoning a hardware corrupted page puts page back buddy only, the
kernel has a chance to access the page with *NOT PRESENT* KPTE.  This
leads BUG during accessing on the corrupted KPTE.

Suggested by David&Naoya, disable unpoison mechanism when a real HW error
happens to avoid BUG like this:

 Unpoison: Software-unpoisoned page 0x61234
 BUG: unable to handle page fault for address: ffff888061234000
 #PF: supervisor write access in kernel mode
 #PF: error_code(0x0002) - not-present page
 PGD 2c01067 P4D 2c01067 PUD 107267063 PMD 10382b063 PTE 800fffff9edcb062
 Oops: 0002 [#1] PREEMPT SMP NOPTI
 CPU: 4 PID: 26551 Comm: stress Kdump: loaded Tainted: G   M       OE     5.18.0.bm.1-amd64 #7
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ...
 RIP: 0010:clear_page_erms+0x7/0x10
 Code: ...
 RSP: 0000:ffffc90001107bc8 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: 0000000000000901 RCX: 0000000000001000
 RDX: ffffea0001848d00 RSI: ffffea0001848d40 RDI: ffff888061234000
 RBP: ffffea0001848d00 R08: 0000000000000901 R09: 0000000000001276
 R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000001
 R13: 0000000000000000 R14: 0000000000140dca R15: 0000000000000001
 FS:  00007fd8b2333740(0000) GS:ffff88813fd00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: ffff888061234000 CR3: 00000001023d2005 CR4: 0000000000770ee0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 PKRU: 55555554
 Call Trace:
  <TASK>
  prep_new_page+0x151/0x170
  get_page_from_freelist+0xca0/0xe20
  ? sysvec_apic_timer_interrupt+0xab/0xc0
  ? asm_sysvec_apic_timer_interrupt+0x1b/0x20
  __alloc_pages+0x17e/0x340
  __folio_alloc+0x17/0x40
  vma_alloc_folio+0x84/0x280
  __handle_mm_fault+0x8d4/0xeb0
  handle_mm_fault+0xd5/0x2a0
  do_user_addr_fault+0x1d0/0x680
  ? kvm_read_and_reset_apf_flags+0x3b/0x50
  exc_page_fault+0x78/0x170
  asm_exc_page_fault+0x27/0x30

Link: https://lkml.kernel.org/r/20220615093209.259374-2-pizhenwei@bytedance.com
Fixes: 847ce401df ("HWPOISON: Add unpoisoning support")
Fixes: 17fae1294a ("x86/{mce,mm}: Unmap the entire page if the whole page is affected and poisoned")
Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>	[5.8+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-06-16 19:11:32 -07:00
Linus Torvalds 98931dd95f Yang Shi has improved the behaviour of khugepaged collapsing of readonly
file-backed transparent hugepages.
 
 Johannes Weiner has arranged for zswap memory use to be tracked and
 managed on a per-cgroup basis.
 
 Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for runtime
 enablement of the recent huge page vmemmap optimization feature.
 
 Baolin Wang contributes a series to fix some issues around hugetlb
 pagetable invalidation.
 
 Zhenwei Pi has fixed some interactions between hwpoisoned pages and
 virtualization.
 
 Tong Tiangen has enabled the use of the presently x86-only
 page_table_check debugging feature on arm64 and riscv.
 
 David Vernet has done some fixup work on the memcg selftests.
 
 Peter Xu has taught userfaultfd to handle write protection faults against
 shmem- and hugetlbfs-backed files.
 
 More DAMON development from SeongJae Park - adding online tuning of the
 feature and support for monitoring of fixed virtual address ranges.  Also
 easier discovery of which monitoring operations are available.
 
 Nadav Amit has done some optimization of TLB flushing during mprotect().
 
 Neil Brown continues to labor away at improving our swap-over-NFS support.
 
 David Hildenbrand has some fixes to anon page COWing versus
 get_user_pages().
 
 Peng Liu fixed some errors in the core hugetlb code.
 
 Joao Martins has reduced the amount of memory consumed by device-dax's
 compound devmaps.
 
 Some cleanups of the arch-specific pagemap code from Anshuman Khandual.
 
 Muchun Song has found and fixed some errors in the TLB flushing of
 transparent hugepages.
 
 Roman Gushchin has done more work on the memcg selftests.
 
 And, of course, many smaller fixes and cleanups.  Notably, the customary
 million cleanup serieses from Miaohe Lin.
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Merge tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:
 "Almost all of MM here. A few things are still getting finished off,
  reviewed, etc.

   - Yang Shi has improved the behaviour of khugepaged collapsing of
     readonly file-backed transparent hugepages.

   - Johannes Weiner has arranged for zswap memory use to be tracked and
     managed on a per-cgroup basis.

   - Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for
     runtime enablement of the recent huge page vmemmap optimization
     feature.

   - Baolin Wang contributes a series to fix some issues around hugetlb
     pagetable invalidation.

   - Zhenwei Pi has fixed some interactions between hwpoisoned pages and
     virtualization.

   - Tong Tiangen has enabled the use of the presently x86-only
     page_table_check debugging feature on arm64 and riscv.

   - David Vernet has done some fixup work on the memcg selftests.

   - Peter Xu has taught userfaultfd to handle write protection faults
     against shmem- and hugetlbfs-backed files.

   - More DAMON development from SeongJae Park - adding online tuning of
     the feature and support for monitoring of fixed virtual address
     ranges. Also easier discovery of which monitoring operations are
     available.

   - Nadav Amit has done some optimization of TLB flushing during
     mprotect().

   - Neil Brown continues to labor away at improving our swap-over-NFS
     support.

   - David Hildenbrand has some fixes to anon page COWing versus
     get_user_pages().

   - Peng Liu fixed some errors in the core hugetlb code.

   - Joao Martins has reduced the amount of memory consumed by
     device-dax's compound devmaps.

   - Some cleanups of the arch-specific pagemap code from Anshuman
     Khandual.

   - Muchun Song has found and fixed some errors in the TLB flushing of
     transparent hugepages.

   - Roman Gushchin has done more work on the memcg selftests.

  ... and, of course, many smaller fixes and cleanups. Notably, the
  customary million cleanup serieses from Miaohe Lin"

* tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (381 commits)
  mm: kfence: use PAGE_ALIGNED helper
  selftests: vm: add the "settings" file with timeout variable
  selftests: vm: add "test_hmm.sh" to TEST_FILES
  selftests: vm: check numa_available() before operating "merge_across_nodes" in ksm_tests
  selftests: vm: add migration to the .gitignore
  selftests/vm/pkeys: fix typo in comment
  ksm: fix typo in comment
  selftests: vm: add process_mrelease tests
  Revert "mm/vmscan: never demote for memcg reclaim"
  mm/kfence: print disabling or re-enabling message
  include/trace/events/percpu.h: cleanup for "percpu: improve percpu_alloc_percpu event trace"
  include/trace/events/mmflags.h: cleanup for "tracing: incorrect gfp_t conversion"
  mm: fix a potential infinite loop in start_isolate_page_range()
  MAINTAINERS: add Muchun as co-maintainer for HugeTLB
  zram: fix Kconfig dependency warning
  mm/shmem: fix shmem folio swapoff hang
  cgroup: fix an error handling path in alloc_pagecache_max_30M()
  mm: damon: use HPAGE_PMD_SIZE
  tracing: incorrect isolate_mote_t cast in mm_vmscan_lru_isolate
  nodemask.h: fix compilation error with GCC12
  ...
2022-05-26 12:32:41 -07:00
Linus Torvalds 88a618920e It was a moderately busy cycle for documentation; highlights include:
- After a long period of inactivity, the Japanese translations are seeing
    some much-needed maintenance and updating.
 
  - Reworked IOMMU documentation
 
  - Some new documentation for static-analysis tools
 
  - A new overall structure for the memory-management documentation.  This
    is an LSFMM outcome that, it is hoped, will help encourage developers to
    fill in the many gaps.  Optimism is eternal...but hopefully it will
    work.
 
  - More Chinese translations.
 
 Plus the usual typo fixes, updates, etc.
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Merge tag 'docs-5.19' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It was a moderately busy cycle for documentation; highlights include:

   - After a long period of inactivity, the Japanese translations are
     seeing some much-needed maintenance and updating.

   - Reworked IOMMU documentation

   - Some new documentation for static-analysis tools

   - A new overall structure for the memory-management documentation.
     This is an LSFMM outcome that, it is hoped, will help encourage
     developers to fill in the many gaps. Optimism is eternal...but
     hopefully it will work.

   - More Chinese translations.

  Plus the usual typo fixes, updates, etc"

* tag 'docs-5.19' of git://git.lwn.net/linux: (70 commits)
  docs: pdfdocs: Add space for chapter counts >= 100 in TOC
  docs/zh_CN: Add dev-tools/gdb-kernel-debugging.rst Chinese translation
  input: Docs: correct ntrig.rst typo
  input: Docs: correct atarikbd.rst typos
  MAINTAINERS: Become the docs/zh_CN maintainer
  docs/zh_CN: fix devicetree usage-model translation
  mm,doc: Add new documentation structure
  Documentation: drop more IDE boot options and ide-cd.rst
  Documentation/process: use scripts/get_maintainer.pl on patches
  MAINTAINERS: Add entry for DOCUMENTATION/JAPANESE
  docs/trans/ja_JP/howto: Don't mention specific kernel versions
  docs/ja_JP/SubmittingPatches: Request summaries for commit references
  docs/ja_JP/SubmittingPatches: Add Suggested-by as a standard signature
  docs/ja_JP/SubmittingPatches: Randy has moved
  docs/ja_JP/SubmittingPatches: Suggest the use of scripts/get_maintainer.pl
  docs/ja_JP/SubmittingPatches: Update GregKH links
  Documentation/sysctl: document max_rcu_stall_to_panic
  Documentation: add missing angle bracket in cgroup-v2 doc
  Documentation: dev-tools: use literal block instead of code-block
  docs/zh_CN: add vm numa translation
  ...
2022-05-25 11:17:41 -07:00
Linus Torvalds 2e17ce1106 slab changes for 5.19
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Merge tag 'slab-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

Pull slab updates from Vlastimil Babka:

 - Conversion of slub_debug stack traces to stackdepot, allowing more
   useful debugfs-based inspection for e.g. memory leak debugging.
   Allocation and free debugfs info now includes full traces and is
   sorted by the unique trace frequency.

   The stackdepot conversion was already attempted last year but
   reverted by ae14c63a9f. The memory overhead (while not actually
   enabled on boot) has been meanwhile solved by making the large
   stackdepot allocation dynamic. The xfstest issues haven't been
   reproduced on current kernel locally nor in -next, so the slab cache
   layout changes that originally made that bug manifest were probably
   not the root cause.

 - Refactoring of dma-kmalloc caches creation.

 - Trivial cleanups such as removal of unused parameters, fixes and
   clarifications of comments.

 - Hyeonggon Yoo joins as a reviewer.

* tag 'slab-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
  MAINTAINERS: add myself as reviewer for slab
  mm/slub: remove unused kmem_cache_order_objects max
  mm: slab: fix comment for __assume_kmalloc_alignment
  mm: slab: fix comment for ARCH_KMALLOC_MINALIGN
  mm/slub: remove unneeded return value of slab_pad_check
  mm/slab_common: move dma-kmalloc caches creation into new_kmalloc_cache()
  mm/slub: remove meaningless node check in ___slab_alloc()
  mm/slub: remove duplicate flag in allocate_slab()
  mm/slub: remove unused parameter in setup_object*()
  mm/slab.c: fix comments
  slab, documentation: add description of debugfs files for SLUB caches
  mm/slub: sort debugfs output by frequency of stack traces
  mm/slub: distinguish and print stack traces in debugfs files
  mm/slub: use stackdepot to save stack trace in objects
  mm/slub: move struct track init out of set_track()
  lib/stackdepot: allow requesting early initialization dynamically
  mm/slub, kunit: Make slub_kunit unaffected by user specified flags
  mm/slab: remove some unused functions
2022-05-25 10:24:04 -07:00
Fabio M. De Francesco 110bf7a523 Documentation/vm: rework "Temporary Virtual Mappings" section
Extend and rework the "Temporary Virtual Mappings" section of the
highmem.rst documentation.

Despite the local kmaps were introduced by Thomas Gleixner in October
2020, documentation was still missing information about them.  These
additions rely largely on Gleixner's patches, Jonathan Corbet's LWN
articles, comments by Ira Weiny and Matthew Wilcox, and in-code comments
from ./include/linux/highmem.h.

1) Add a paragraph to document kmap_local_page().
2) Reorder the list of functions by decreasing order of preference
   of use.
3) Rework part of the kmap() entry in list.

Link: https://lkml.kernel.org/r/20220428212455.892-5-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-13 16:48:55 -07:00
Fabio M. De Francesco 85a85e7601 Documentation/vm: move "Using kmap-atomic" to highmem.h
The use of kmap_atomic() is new code is being deprecated in favor of
kmap_local_page().  For this reason the "Using kmap_atomic" section in
highmem.rst is obsolete and unnecessary, but it can still help developers
if it were moved to kdocs in highmem.h.

Therefore, move the relevant parts of this section from highmem.rst and
merge them with the kdocs in highmem.h.

Link: https://lkml.kernel.org/r/20220428212455.892-4-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-13 16:48:55 -07:00
Fabio M. De Francesco 174270c2d6 Documentation/vm: include kdocs from highmem*.h into highmem.rst
kernel-docs that are in include/linux/highmem.h and in
include/linux/highmem-internal.h should be included in highmem.rst.

Use kdocs directives to include the above-mentioned comments into
highmem.rst.

Link: https://lkml.kernel.org/r/20220428212455.892-3-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-13 16:48:55 -07:00
Akira Yokosawa d1ed51fcdb docs: vm/page_owner: tweak literal block in STANDARD FORMAT SPECIFIERS
A semantic conflict between commit 5603f9bdea ("docs: vm/page_owner: use
literal blocks for param description") and a change queued for v5.19
authored by Jiajian Ye ("tools/vm/page_owner_sort.c: support sorting
blocks by multiple keys") results in a warning from "make htmldocs"
saying:

  [...]/vm/page_owner.rst:176: WARNING: Literal block expected; none found.

This is because a literal block in ReST ends at a line which has the same
indent as the paragraph preceding it.  In this case the one with no
indent.

Indent the two "For --xxxx option:" lines by two columns and make the
whole section a literal block.

While at it, fix indents by white spaces of "ator" keys.

Link: https://lkml.kernel.org/r/fdfecc82-d41e-6d8a-738d-4beb6faa27fb@gmail.com
Signed-of-by: Akira Yokosawa <akiyks@gmail.com>
Reported-by: Shenghong Han <hanshenghong2019@email.szu.edu.cn>
Cc: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Yongqiang Liu <liuyongqiang13@huawei.com>
Cc: Yuhong Feng <yuhongf@szu.edu.cn>
Cc: Haowen Bai <baihaowen@meizu.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-13 07:20:18 -07:00
Matthew Wilcox (Oracle) 481cc97349 mm,doc: Add new documentation structure
Closely following the outline of Mel Gorman's book "Understanding the
Linux Virtual Memory Manager", add a new outline.  Preserve the current
contents of the mm underneath the new outline so we can transition those
documents to a more sensible place later.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20220507134947.444287-1-willy@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-05-09 16:41:24 -06:00
Joao Martins 4917f55b4e mm/sparse-vmemmap: improve memory savings for compound devmaps
A compound devmap is a dev_pagemap with @vmemmap_shift > 0 and it means
that pages are mapped at a given huge page alignment and utilize uses
compound pages as opposed to order-0 pages.

Take advantage of the fact that most tail pages look the same (except the
first two) to minimize struct page overhead.  Allocate a separate page for
the vmemmap area which contains the head page and separate for the next 64
pages.  The rest of the subsections then reuse this tail vmemmap page to
initialize the rest of the tail pages.

Sections are arch-dependent (e.g.  on x86 it's 64M, 128M or 512M) and when
initializing compound devmap with big enough @vmemmap_shift (e.g.  1G PUD)
it may cross multiple sections.  The vmemmap code needs to consult @pgmap
so that multiple sections that all map the same tail data can refer back
to the first copy of that data for a given gigantic page.

On compound devmaps with 2M align, this mechanism lets 6 pages be saved
out of the 8 necessary PFNs necessary to set the subsection's 512 struct
pages being mapped.  On a 1G compound devmap it saves 4094 pages.

Altmap isn't supported yet, given various restrictions in altmap pfn
allocator, thus fallback to the already in use vmemmap_populate().  It is
worth noting that altmap for devmap mappings was there to relieve the
pressure of inordinate amounts of memmap space to map terabytes of pmem. 
With compound pages the motivation for altmaps for pmem gets reduced.

Link: https://lkml.kernel.org/r/20220420155310.9712-5-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-28 23:16:16 -07:00
Joao Martins 60a427db0f mm/hugetlb_vmemmap: move comment block to Documentation/vm
In preparation for device-dax for using hugetlbfs compound page tail
deduplication technique, move the comment block explanation into a common
place in Documentation/vm.

Link: https://lkml.kernel.org/r/20220420155310.9712-4-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-28 23:16:15 -07:00
Yixuan Cao f09654bb88 tools/vm/page_owner_sort.c: provide allocator labelling and update --cull and --sort options
An application is suspected of having memory leak when its memory
consumption is high and keeps increasing.  There are several commonly used
memory allocators: slab, cma, vmalloc, etc.  The memory leak
identification can be sped up if the page information allocated by an
allocator can be analyzed separately.

This patch provides supports for memory allocator labelling for slab,
vmalloc, and cma.  The pages allocated by slab and cma can be confirmed
from the "PFN" line according to the kernel codes, and the label of the
vmalloc allocator can be obtained by analyzing the stack trace.  Thanks
for Vlastimil Babka's constructive suggestions.

Based on Yinan Zhang's study, the call chain of vmalloc() is vmalloc() ->
...  -> __vmalloc_node_range() -> __vmalloc_area_node(). 
__vmalloc_area_node() requests memory through the interface of buddy
allocation system.  In the current version, __vmalloc_area_node() uses
four interfaces: alloc_pages_bulk_array_mempolicy(),
alloc_pages_bulk_array_node(), alloc_pages() and alloc_pages_node().  By
disassembling the code, we find that __vmalloc_area_node() is expanded in
__vmalloc_node_range().  So __vmalloc_area_node is not in the stack trace.

On the test machine, the stack trace of pages allocated by vmalloc has the
following four forms:

__alloc_pages_bulk+0x230/0x6a0
__vmalloc_node_range+0x19c/0x598

alloc_pages_bulk_array_mempolicy+0xbc/0x278
__vmalloc_node_range+0x1e8/0x598

__alloc_pages+0x160/0x2b0
__vmalloc_node_range+0x234/0x598

alloc_pages+0xac/0x150
__vmalloc_node_range+0x44c/0x598

Therefore, in two consecutive lines of stacktrace, if the first line
contains the word "alloc_pages" and the second line contains the word
"__vmalloc_node_range", it can be determined that the page is allocated by
vmalloc.  And the function offset and size are not the same on different
machines, so there is no need to match them.

At the same time, this patch updates the --cull and --sort options to
support allocator-based merge statistics and sorting.  The added functions
are fully compatible with the original work.  When using, you can use
"allocator", or abbreviated as "ator".  Relevant updates have also been
made in the documentation(Documentation/vm/page_owner.rst).

Example:
./page_owner_sort <input> <output> --cull=st,pid,name,allocator
./page_owner_sort <input> <output> --sort=ator,pid,name

This work is coauthored by Jiajian Ye, Yinan Zhang, Shenghong Han,
Chongxi Zhao, Yuhong Feng and Yongqiang Liu.

Link: https://lkml.kernel.org/r/20220410132932.9402-1-caoyixuan2019@email.szu.edu.cn
Signed-off-by: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Cc: Haowen Bai <baihaowen@meizu.com>
Cc: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Sean Anderson <seanga2@gmail.com>
Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn>
Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Yongqiang Liu <liuyongqiang13@huawei.com>
Cc: Yuhong Feng <yuhongf@szu.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-28 23:15:57 -07:00
Jiajian Ye ebbeae3638 tools/vm/page_owner_sort.c: support sorting blocks by multiple keys
When viewing page owner information, we may want to sort blocks of
information by multiple keys, since one single key does not uniquely
identify a block. Therefore, following adjustments are made:

1. Add a new --sort option to support sorting blocks of information by
multiple keys.

	./page_owner_sort <input> <output> --sort=<order>
	./page_owner_sort <input> <output> --sort <order>

<order> is a single argument in the form of a comma-separated list,
which offers a way to specify sorting order.

Sorting syntax is [+|-]key[,[+|-]key[,...]]. The ascending or descending
order can be specified by adding the + (ascending, default) or - (descend
-ing) prefix to the key:

	./page_owner_sort <input> <output> [option] --sort -key1,+key2,key3...

For example, to sort the blocks first by task command name in lexicographic
order and then by pid in ascending numerical order, use the following:

	./page_owner_sort <input> <output> --sort=name,+pid

To sort the blocks first by pid in ascending order and then by timestamp
of the page when it is allocated in descending order, use the following:

	./page_owner_sort <input> <output> --sort=pid,-alloc_ts

2. Add explanations of a newly added --sort option in the function usage()
and the document(Documentation/vm/page_owner.rst).

This work is coauthored by
	Yixuan Cao
	Shenghong Han
	Yinan Zhang
	Chongxi Zhao
	Yuhong Feng
	Yongqiang Liu

Link: https://lkml.kernel.org/r/20220401024856.767-3-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn>
Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Yongqiang Liu <liuyongqiang13@huawei.com>
Cc: Yuhong Feng <yuhongf@szu.edu.cn>
Cc: Haowen Bai <baihaowen@meizu.com>
Cc: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-28 23:15:57 -07:00
Jiajian Ye 75382a2dca tools/vm/page_owner_sort.c: support for multi-value selection in single argument
When viewing page owner information, we may want to select blocks whose
PID/TGID/TASK_COMM_NAME appears in a user-specified list for data analysis
and aggregation.  But currently page_owner_sort only supports selecting
blocks associated with only one specified PID/TGID/TASK_COMM_NAME.

Therefore, following adjustments are made to fix the problem:

1. Enhance selecting function to support the selection of multiple
   PIDs/TGIDs/TASK_COMM_NAMEs.

The enhanced usages are as follows:

--pid <pidlist>         Select by pid. This selects the blocks whose PID
                        numbers appear in <pidlist>.
--tgid <tgidlist>       Select by tgid. This selects the blocks whose
                        TGID numbers appear in <tgidlist>.
--name <cmdlist>        Select by task command name. This selects the
                        blocks whose task command name appear in <cmdlist>.

Where <pidlist>, <tgidlist>, <cmdlist> are single arguments in the form of
a comma-separated list,which offers a way to specify individual selecting
rules.

For example, if you want to select blocks whose tgids are 1, 2 or 3, you
have to use 4 commands as follows:

        ./page_owner_sort <input> <output1> --tgid=1
        ./page_owner_sort <input> <output2> --tgid=2
        ./page_owner_sort <input> <output3> --tgid=3
        cat <output1> <output2> <output3> > <output>

With this patch, you can use only 1 command to obtain the same result as
above:

        ./page_owner_sort <input> <output1> --tgid=1,2,3

2. Update explanations of --pid, --tgid and --name in the function
   usage() and the document(Documents/vm/page_owner.rst).

This work is coauthored by
        Yixuan Cao
        Shenghong Han
        Yinan Zhang
        Chongxi Zhao
        Yuhong Feng
        Yongqiang Liu

Link: https://lkml.kernel.org/r/20220401024856.767-2-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn>
Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Yongqiang Liu <liuyongqiang13@huawei.com>
Cc: Yuhong Feng <yuhongf@szu.edu.cn>
Cc: Haowen Bai <baihaowen@meizu.com>
Cc: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-28 23:15:56 -07:00
Akira Yokosawa 5603f9bdea docs: vm/page_owner: use literal blocks for param description
Sphinx generates hard-to-read lists of parameters at the bottom of the
page.  Fix them by putting literal-block markers of "::" in front of
them.

Link: https://lkml.kernel.org/r/cfd3bcc0-b51d-0c68-c065-ca1c4c202447@gmail.com
Signed-off-by: Akira Yokosawa <akiyks@gmail.com>
Fixes: 57f2b54a93 ("Documentation/vm/page_owner.rst: update the documentation")
Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn>
Cc: Haowen Bai <baihaowen@meizu.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Alex Shi <seakeel@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-04-27 13:28:48 -07:00
Bagas Sanjaya e01159c713 Documentation: arch_pgtable_helpers: demote pgtable list headings
All page title headings in arch_pgtable_helpers.txt except
"Architecture Page Table Helpers" should have been subheadings instead.

Demote them to chapter headings.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-04-16 02:44:49 -06:00
Oliver Glitta 9f04b55f00 slab, documentation: add description of debugfs files for SLUB caches
Add description of debugfs files alloc_traces and free_traces
to SLUB cache documentation.

[ vbabka@suse.cz: some rewording ]

Signed-off-by: Oliver Glitta <glittao@gmail.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: linux-doc@vger.kernel.org
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
2022-04-06 11:09:48 +02:00
Yinan Zhang c89b3ad2de doc/vm/page_owner.rst: remove content related to -c option
-c option has been removed from page_owner_sort.c.

Remove the usage of -c option from Documentation.

This work is coauthored by
        Shenghong Han
        Yixuan Cao
        Chongxi Zhao
        Jiajian Ye
        Yuhong Feng
        Yongqiang Liu

Link: https://lkml.kernel.org/r/20220326085920.1470081-2-zhangyinan2019@email.szu.edu.cn
Signed-off-by: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Sean Anderson <seanga2@gmail.com>
Cc: Tang Bin <tangbin@cmss.chinamobile.com>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Cc: Georgi Djakov <georgi.djakov@linaro.org>
Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Cc: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Yuhong Feng <yuhongf@szu.edu.cn>
Cc: Yongqiang Liu <liuyongqiang13@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-04-01 11:46:09 -07:00
Hugh Dickins 577e9846f8 mm/munlock: update Documentation/vm/unevictable-lru.rst
Update Documentation/vm/unevictable-lru.rst to reflect the changes made
by the mm/munlock series: keeping an mlock_count instead of page_mlock()
(formerly try_to_munlock()) and munlock_vma_pages_all() etc.  Also make
other little updates or cleanups wherever noticed.

But, I apologize, this is already out of date, in that "folio" appears
nowhere: 5.18 will be in a transitional state from "page" to "folio",
and documenting its current mix of the two does not help to understand
"the Unevictable LRU".  Should be revisited when naming is more settled.

Link: https://lkml.kernel.org/r/3753962-d491-bf60-f59f-51bfe84fd6a0@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: David Hildenbrand <david@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-04-01 11:46:09 -07:00
Linus Torvalds 636f64db07 - More noinstr fixes
- Add an erratum workaround for Intel CPUs which, in certain
 circumstances, end up consuming an unrelated uncorrectable memory error
 when using fast string copy insns
 
 - Remove the MCE tolerance level control as it is not really needed or
 used anymore
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Merge tag 'ras_core_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RAS updates from Borislav Petkov:

 - More noinstr fixes

 - Add an erratum workaround for Intel CPUs which, in certain
   circumstances, end up consuming an unrelated uncorrectable memory
   error when using fast string copy insns

 - Remove the MCE tolerance level control as it is not really needed or
   used anymore

* tag 'ras_core_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Remove the tolerance level control
  x86/mce: Work around an erratum on fast string copy instructions
  x86/mce: Use arch atomic and bit helpers
2022-03-25 12:34:53 -07:00
Jiajian Ye 9c8a0a8e59 tools/vm/page_owner_sort.c: support for user-defined culling rules
When viewing page owner information, we may want to cull blocks of
information with our own rules.  So it is important to enhance culling
function to provide the support for customizing culling rules.
Therefore, following adjustments are made:

1. Add --cull option to support the culling of blocks of information
   with user-defined culling rules.

	./page_owner_sort <input> <output> --cull=<rules>
	./page_owner_sort <input> <output> --cull <rules>

  <rules> is a single argument in the form of a comma-separated list to
  specify individual culling rules, by the sequence of keys k1,k2, ....
  Mixed use of abbreviated and complete-form of keys is allowed.

  For reference, please see the document(Documentation/vm/page_owner.rst).

Now, assuming two blocks in the input file are as follows:

	Page allocated via order 0, mask xxxx, pid 1, tgid 1 (task_name_demo)
	PFN xxxx
	 prep_new_page+0xd0/0xf8
	 get_page_from_freelist+0x4a0/0x1290
	 __alloc_pages+0x168/0x340
	 alloc_pages+0xb0/0x158

	Page allocated via order 0, mask xxxx, pid 32, tgid 32 (task_name_demo)
	PFN xxxx
	 prep_new_page+0xd0/0xf8
	 get_page_from_freelist+0x4a0/0x1290
	 __alloc_pages+0x168/0x340
	 alloc_pages+0xb0/0x158

If we want to cull the blocks by stacktrace and task command name, we can
use this command:

	./page_owner_sort <input> <output> --cull=stacktrace,name

The output would be like:

	2 times, 2 pages, task_comm_name: task_name_demo
	 prep_new_page+0xd0/0xf8
	 get_page_from_freelist+0x4a0/0x1290
	 __alloc_pages+0x168/0x340
	 alloc_pages+0xb0/0x158

As we can see, these two blocks are culled successfully, for they share
the same pid and task command name.

However, if we want to cull the blocks by pid, stacktrace and task command
name, we can this command:

	./page_owner_sort <input> <output> --cull=stacktrace,name,pid

The output would be like:

	1 times, 1 pages, PID 1, task_comm_name: task_name_demo
	 prep_new_page+0xd0/0xf8
	 get_page_from_freelist+0x4a0/0x1290
	 __alloc_pages+0x168/0x340
	 alloc_pages+0xb0/0x158

	1 times, 1 pages, PID 32, task_comm_name: task_name_demo
	 prep_new_page+0xd0/0xf8
	 get_page_from_freelist+0x4a0/0x1290
	 __alloc_pages+0x168/0x340
	 alloc_pages+0xb0/0x158

As we can see, these two blocks are failed to cull, for their PIDs are
different.

2. Add explanations of --cull options to the document.

This work is coauthored by
	Yixuan Cao
	Shenghong Han
	Yinan Zhang
	Chongxi Zhao
	Yuhong Feng

Link: https://lkml.kernel.org/r/20220312145834.624-1-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn>
Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Cc: Yuhong Feng <yuhongf@szu.edu.cn>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:45 -07:00
Jiajian Ye 8ea8613a61 tools/vm/page_owner_sort.c: support for selecting by PID, TGID or task command name
When viewing page owner information, we may also need to select the blocks
by PID, TGID or task command name, which helps to get more accurate page
allocation information as needed.

Therefore, following adjustments are made:

1. Add three new options, including --pid, --tgid and --name, to support
   the selection of information blocks by a specific pid, tgid and task
   command name. In addtion, multiple options are allowed to be used at
   the same time.

	./page_owner_sort [input] [output] --pid <PID>
	./page_owner_sort [input] [output] --tgid <TGID>
	./page_owner_sort [input] [output] --name <TASK_COMMAND_NAME>

   Assuming a scenario when a multi-threaded program, ./demo (PID =
   5280), is running, and ./demo creates a child process (PID = 5281).

	$ps
	PID   TTY        TIME   CMD
	5215  pts/0    00:00:00  bash
	5280  pts/0    00:00:00  ./demo
	5281  pts/0    00:00:00  ./demo
	5282  pts/0    00:00:00  ps

   It would be better to filter out the records with tgid=5280 and the
   task name "demo" when debugging the parent process, and the specific
   usage is

	./page_owner_sort [input] [output] --tgid 5280 --name demo

2. Add explanations of three new options, including --pid, --tgid and
   --name, to the document.

This work is coauthored by
	Shenghong Han <hanshenghong2019@email.szu.edu.cn>,
	Yixuan Cao <caoyixuan2019@email.szu.edu.cn>,
	Yinan Zhang <zhangyinan2019@email.szu.edu.cn>,
	Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>,
	Yuhong Feng <yuhongf@szu.edu.cn>.

Link: https://lkml.kernel.org/r/1646835223-7584-1-git-send-email-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Sean Anderson <seanga2@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:45 -07:00
Jiajian Ye 194d52d771 tools/vm/page_owner_sort: support for sorting by task command name
When viewing page owner information, we may also need to the block to be
sorted by task command name.  Therefore, the following adjustments are
made:

1. Add a member variable to record task command name of block.

2. Add a new -n option to sort the information of blocks by task command
   name.

3. Add -n option explanation in the document.

Link: https://lkml.kernel.org/r/20220306030640.43054-2-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Sean Anderson <seanga2@gmail.com>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Cc: <zhaochongxi2019@email.szu.edu.cn>
Cc: <hanshenghong2019@email.szu.edu.cn>
Cc: <zhangyinan2019@email.szu.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:45 -07:00
Jiajian Ye cf3c2c8678 tools/vm/page_owner_sort.c: support sorting by tgid and update documentation
When the "page owner" information is read, the information sorted
by TGID is expected.

As a result, the following adjustments have been made:

1. Add a new -P option to sort the information of blocks by TGID in
   ascending order.

2. Adjust the order of member variables in block_list strust to avoid
   one 4 byte hole.

3. Add -P option explanation in the document.

Link: https://lkml.kernel.org/r/20220301151438.166118-3-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:45 -07:00
Jiajian Ye 59d7cb27d5 tools/vm/page_owner_sort.c: fix comments
Two adjustments are made:

1. Correct a grammatical error: replace the "what" in "Do the job what
   you want to debug" with "that".

2. Replace "has not been" with "has been" in the description of the -f
   option: According to Commit b1c9ba071e7d ("tools/vm/page_owner_sort.c:
   fix the instructions for use"), the description of the "-f" option is
   "Filter out the information of blocks whose memory has been released."

Link: https://lkml.kernel.org/r/20220301151438.166118-1-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:45 -07:00
Shuah Khan 2e9449856b Documentation/vm/page_owner.rst: fix unexpected indentation warns
Fix Unexpected indentation warns in page_owner:

  Documentation/vm/page_owner.rst:92: WARNING: Unexpected indentation.
  Documentation/vm/page_owner.rst:96: WARNING: Unexpected indentation.
  Documentation/vm/page_owner.rst:107: WARNING: Unexpected indentation.

Link: https://lkml.kernel.org/r/20211215001929.47866-1-skhan@linuxfoundation.org
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:44 -07:00
Shenghong Han 57f2b54a93 Documentation/vm/page_owner.rst: update the documentation
Update the documentation of ``page_owner``.

[akpm@linux-foundation.org: small grammatical tweaks]

Link: https://lkml.kernel.org/r/20211214134736.2569-1-hanshenghong2019@email.szu.edu.cn
Signed-off-by: Shenghong Han <hanshenghong2019@email.szu.edu.cn>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Georgi Djakov <georgi.djakov@linaro.org>
Cc: Liam Mark <lmark@codeaurora.org>
Cc: Tang Bin <tangbin@cmss.chinamobile.com>
Cc: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Cc: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:44 -07:00
Linus Torvalds 3bf03b9a08 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - A few misc subsystems: kthread, scripts, ntfs, ocfs2, block, and vfs

 - Most the MM patches which precede the patches in Willy's tree: kasan,
   pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
   sparsemem, vmalloc, pagealloc, memory-failure, mlock, hugetlb,
   userfaultfd, vmscan, compaction, mempolicy, oom-kill, migration, thp,
   cma, autonuma, psi, ksm, page-poison, madvise, memory-hotplug, rmap,
   zswap, uaccess, ioremap, highmem, cleanups, kfence, hmm, and damon.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (227 commits)
  mm/damon/sysfs: remove repeat container_of() in damon_sysfs_kdamond_release()
  Docs/ABI/testing: add DAMON sysfs interface ABI document
  Docs/admin-guide/mm/damon/usage: document DAMON sysfs interface
  selftests/damon: add a test for DAMON sysfs interface
  mm/damon/sysfs: support DAMOS stats
  mm/damon/sysfs: support DAMOS watermarks
  mm/damon/sysfs: support schemes prioritization
  mm/damon/sysfs: support DAMOS quotas
  mm/damon/sysfs: support DAMON-based Operation Schemes
  mm/damon/sysfs: support the physical address space monitoring
  mm/damon/sysfs: link DAMON for virtual address spaces monitoring
  mm/damon: implement a minimal stub for sysfs-based DAMON interface
  mm/damon/core: add number of each enum type values
  mm/damon/core: allow non-exclusive DAMON start/stop
  Docs/damon: update outdated term 'regions update interval'
  Docs/vm/damon/design: update DAMON-Idle Page Tracking interference handling
  Docs/vm/damon: call low level monitoring primitives the operations
  mm/damon: remove unnecessary CONFIG_DAMON option
  mm/damon/paddr,vaddr: remove damon_{p,v}a_{target_valid,set_operations}()
  mm/damon/dbgfs-test: fix is_target_id() change
  ...
2022-03-22 16:11:53 -07:00
SeongJae Park 4c1f287f8c Docs/damon: update outdated term 'regions update interval'
Before DAMON is merged in the mainline, the concept of 'regions update
interval' has generalized to be used as the time interval for update of
any monitoring operations related data structure, but the document has not
updated properly.  This commit updates the document for better
consistency.

Link: https://lkml.kernel.org/r/20220222170100.17068-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park 742cc2bfce Docs/vm/damon/design: update DAMON-Idle Page Tracking interference handling
In DAMON's early development stage before it be merged in the mainline, it
was first designed to work exclusively with Idle page tracking to avoid
any interference between each other.  Later, but still before be merged in
the mainline, because Idle page tracking is fully under the control of
sysadmins, we made the resolving of conflict as the responsibility of
sysadmins.  The document is not updated for the change, though.  This
commit updates the document for that.

Link: https://lkml.kernel.org/r/20220222170100.17068-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park 561f4fc497 Docs/vm/damon: call low level monitoring primitives the operations
Patch series "Docs/damon: Update documents for better consistency".

Some of DAMON document are not properly updated for latest version.  This
patchset updates such parts.

This patch (of 3):

DAMON code calls the low level monitoring primitives implementations the
monitoring operations.  The documentation would have no problem at still
calling those primitives implementation because there is no real
difference in the concepts, but making it more consistent with the code
would make it better.  This commit therefore convert sentences in the doc
specifically pointing the implementations of the primitives to call it
monitoring operations.

Link: https://lkml.kernel.org/r/20220222170100.17068-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20220222170100.17068-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
Jonathan Corbet 18ab307823 docs: fix RST error in vm/page_owner.rst
Commit f7df2b1cf0 ("tools/vm/page_owner_sort.c: count and sort by mem")
added a literal text block without the necessary markup, leading to these
warnings in the docs build:

  Documentation/vm/page_owner.rst:92: WARNING: Unexpected indentation.
  Documentation/vm/page_owner.rst:96: WARNING: Unexpected indentation.
  Documentation/vm/page_owner.rst:107: WARNING: Unexpected indentation.

Add the necessary colons and make the build quieter.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24 12:57:10 -07:00
Yixuan Cao 024314d6d5 Documentation/vm/page_owner.rst: fix language
There are some words that need to be fixed.

Thanks for Shuah Khan's constructive suggestions.
The text has been fixed as follows.

a. So, if you'd like to use it, you need
to add "page_owner=on" into your boot cmdline.

Here, "into" has been replaced with "to".

b. ...page owner is disabled in runtime due to no
enabling, boot option, runtime overhead is marginal.

Here, "no" has been replaced with "not".

Signed-off-by: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20220223134104.2663-1-caoyixuan2019@email.szu.edu.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-24 12:17:12 -07:00
Borislav Petkov 7f1b8e0d63 x86/mce: Remove the tolerance level control
This is pretty much unused and not really useful. What is more, all
relevant MCA hardware has recoverable machine checks support so there's
no real need to tweak MCA tolerance levels in order to *maybe* extend
machine lifetime.

So rip it out.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/YcDq8PxvKtTENl/e@zn.tnic
2022-02-23 11:09:25 +01:00
Paul Menzel 854d0982ee docs/vm: Fix typo in *harden*
Fixes: df4e817b71 ("mm: page table check")
Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
Link: https://lore.kernel.org/r/20220117111338.115455-1-pmenzel@molgen.mpg.de
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-01-27 11:22:34 -07:00
Christoph Hellwig 0b364446d7 frontswap: remove frontswap_shrink
frontswap_shrink is never called, so remove it.

Link: https://lkml.kernel.org/r/20211224062246.1258487-5-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-22 08:33:38 +02:00
Christoph Hellwig 3d6035f136 frontswap: remove frontswap_writethrough
frontswap_writethrough is never called, so remove it.

Link: https://lkml.kernel.org/r/20211224062246.1258487-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-22 08:33:38 +02:00
Christoph Hellwig 0a4ee51818 mm: remove cleancache
Patch series "remove Xen tmem leftovers".

Since the removal of the Xen tmem driver in 2019, the cleancache hooks
are entirely unused, as are large parts of frontswap.  This series
against linux-next (with the folio changes included) removes
cleancaches, and cuts down frontswap to the bits actually used by zswap.

This patch (of 13):

The cleancache subsystem is unused since the removal of Xen tmem driver
in commit 814bbf49dc ("xen: remove tmem driver").

[akpm@linux-foundation.org: remove now-unreachable code]

Link: https://lkml.kernel.org/r/20211224062246.1258487-1-hch@lst.de
Link: https://lkml.kernel.org/r/20211224062246.1258487-2-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-22 08:33:38 +02:00
Linus Torvalds f56caedaf9 Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "146 patches.

  Subsystems affected by this patch series: kthread, ia64, scripts,
  ntfs, squashfs, ocfs2, vfs, and mm (slab-generic, slab, kmemleak,
  dax, kasan, debug, pagecache, gup, shmem, frontswap, memremap,
  memcg, selftests, pagemap, dma, vmalloc, memory-failure, hugetlb,
  userfaultfd, vmscan, mempolicy, oom-kill, hugetlbfs, migration, thp,
  ksm, page-poison, percpu, rmap, zswap, zram, cleanups, hmm, and
  damon)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (146 commits)
  mm/damon: hide kernel pointer from tracepoint event
  mm/damon/vaddr: hide kernel pointer from damon_va_three_regions() failure log
  mm/damon/vaddr: use pr_debug() for damon_va_three_regions() failure logging
  mm/damon/dbgfs: remove an unnecessary variable
  mm/damon: move the implementation of damon_insert_region to damon.h
  mm/damon: add access checking for hugetlb pages
  Docs/admin-guide/mm/damon/usage: update for schemes statistics
  mm/damon/dbgfs: support all DAMOS stats
  Docs/admin-guide/mm/damon/reclaim: document statistics parameters
  mm/damon/reclaim: provide reclamation statistics
  mm/damon/schemes: account how many times quota limit has exceeded
  mm/damon/schemes: account scheme actions that successfully applied
  mm/damon: remove a mistakenly added comment for a future feature
  Docs/admin-guide/mm/damon/usage: update for kdamond_pid and (mk|rm)_contexts
  Docs/admin-guide/mm/damon/usage: mention tracepoint at the beginning
  Docs/admin-guide/mm/damon/usage: remove redundant information
  Docs/admin-guide/mm/damon/usage: update for scheme quotas and watermarks
  mm/damon: convert macro functions to static inline functions
  mm/damon: modify damon_rand() macro to static inline function
  mm/damon: move damon_rand() definition into damon.h
  ...
2022-01-15 20:37:06 +02:00
Baolin Wang 5d39a7ebc8 mm: migrate: correct the hugetlb migration stats
Correct the migration stats for hugetlb with using compound_nr() instead
of thp_nr_pages(), meanwhile change 'nr_failed_pages' to record the
number of normal pages failed to migrate, including THP and hugetlb, and
'nr_succeeded' will record the number of normal pages migrated
successfully.

[baolin.wang@linux.alibaba.com: fix docs, per Mike]
  Link: https://lkml.kernel.org/r/141bdfc6-f898-3cc3-f692-726c5f6cb74d@linux.alibaba.com

Link: https://lkml.kernel.org/r/71a4b6c22f208728fe8c78ad26375436c4ff9704.1636275127.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 16:30:30 +02:00
Pasha Tatashin df4e817b71 mm: page table check
Check user page table entries at the time they are added and removed.

Allows to synchronously catch memory corruption issues related to double
mapping.

When a pte for an anonymous page is added into page table, we verify
that this pte does not already point to a file backed page, and vice
versa if this is a file backed page that is being added we verify that
this page does not have an anonymous mapping

We also enforce that read-only sharing for anonymous pages is allowed
(i.e.  cow after fork).  All other sharing must be for file pages.

Page table check allows to protect and debug cases where "struct page"
metadata became corrupted for some reason.  For example, when refcnt or
mapcount become invalid.

Link: https://lkml.kernel.org/r/20211221154650.1047963-4-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Xu <weixugc@google.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 16:30:28 +02:00
Pasha Tatashin 08d5b29eac mm: ptep_clear() page table helper
We have ptep_get_and_clear() and ptep_get_and_clear_full() helpers to
clear PTE from user page tables, but there is no variant for simple
clear of a present PTE from user page tables without using a low level
pte_clear() which can be either native or para-virtualised.

Add a new ptep_clear() that can be used in common code to clear PTEs
from page table.  We will need this call later in order to add a hook
for page table check.

Link: https://lkml.kernel.org/r/20211221154650.1047963-3-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Xu <weixugc@google.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 16:30:28 +02:00
Shuah Khan 4b8fec2867 docs/vm: add vmalloced-kernel-stacks document
Add a new document to explain Virtually Mapped Kernel Stack Support.
This is a compilation of information from the code and original patch
series that introduced the Virtually Mapped Kernel Stacks feature.

This document summarizes the feature and provides details on allocation,
free, and stack overflow handling.  Provides reference to available
tests.

Link: https://lkml.kernel.org/r/20211215002004.47981-1-skhan@linuxfoundation.org
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 16:30:28 +02:00
Anshuman Khandual 236476180c mm/debug_vm_pgtable: update comments regarding migration swap entries
Commit 4dd845b5a3 ("mm/swapops: rework swap entry manipulation code")
had changed migtation entry related helpers.  Just update
debug_vm_pgatble() synced documentation to reflect those changes.

Link: https://lkml.kernel.org/r/1641880417-24848-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-15 16:30:26 +02:00
Anssi Hannula dc10ec9879 docs/vm: clarify overcommit amount sysctl behavior
Documentation/vm/overcommit-accounting.rst says that the overcommit
amount can be set via vm.overcommit_ratio and vm.overcommit_kbytes.

Add a clarification that those only take effect in overcommit handling
mode 2 ("Don't overcommit"), i.e. they do not act as an "additional"
limit that is always enforced.

Signed-off-by: Anssi Hannula <anssi.hannula@iki.fi>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20211211194159.3137362-1-anssi.hannula@iki.fi
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-12-16 15:53:22 -07:00
Alistair Popple ab09243aa9 mm/migrate.c: remove MIGRATE_PFN_LOCKED
MIGRATE_PFN_LOCKED is used to indicate to migrate_vma_prepare() that a
source page was already locked during migrate_vma_collect().  If it
wasn't then the a second attempt is made to lock the page.  However if
the first attempt failed it's unlikely a second attempt will succeed,
and the retry adds complexity.  So clean this up by removing the retry
and MIGRATE_PFN_LOCKED flag.

Destination pages are also meant to have the MIGRATE_PFN_LOCKED flag
set, but nothing actually checks that.

Link: https://lkml.kernel.org/r/20211025041608.289017-1-apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-11 09:34:35 -08:00
Linus Torvalds 512b7931ad Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "257 patches.

  Subsystems affected by this patch series: scripts, ocfs2, vfs, and
  mm (slab-generic, slab, slub, kconfig, dax, kasan, debug, pagecache,
  gup, swap, memcg, pagemap, mprotect, mremap, iomap, tracing, vmalloc,
  pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, tools,
  memblock, oom-kill, hugetlbfs, migration, thp, readahead, nommu, ksm,
  vmstat, madvise, memory-hotplug, rmap, zsmalloc, highmem, zram,
  cleanups, kfence, and damon)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (257 commits)
  mm/damon: remove return value from before_terminate callback
  mm/damon: fix a few spelling mistakes in comments and a pr_debug message
  mm/damon: simplify stop mechanism
  Docs/admin-guide/mm/pagemap: wordsmith page flags descriptions
  Docs/admin-guide/mm/damon/start: simplify the content
  Docs/admin-guide/mm/damon/start: fix a wrong link
  Docs/admin-guide/mm/damon/start: fix wrong example commands
  mm/damon/dbgfs: add adaptive_targets list check before enable monitor_on
  mm/damon: remove unnecessary variable initialization
  Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIM
  mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM)
  selftests/damon: support watermarks
  mm/damon/dbgfs: support watermarks
  mm/damon/schemes: activate schemes based on a watermarks mechanism
  tools/selftests/damon: update for regions prioritization of schemes
  mm/damon/dbgfs: support prioritization weights
  mm/damon/vaddr,paddr: support pageout prioritization
  mm/damon/schemes: prioritize regions within the quotas
  mm/damon/selftests: support schemes quotas
  mm/damon/dbgfs: support quotas of schemes
  ...
2021-11-06 14:08:17 -07:00
SeongJae Park c638072107 Docs/DAMON: document physical memory monitoring support
This updates the DAMON documents for the physical memory address space
monitoring support.

Link: https://lkml.kernel.org/r/20211012205711.29216-8-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Amit Shah <amit@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rienjes <rientjes@google.com>
Cc: David Woodhouse <dwmw@amazon.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Leonard Foerster <foersleo@amazon.de>
Cc: Marco Elver <elver@google.com>
Cc: Markus Boehme <markubo@amazon.de>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06 13:30:45 -07:00
SeongJae Park 876d0aac2e docs/vm/damon: remove broken reference
Building DAMON documents warns for a reference to nonexisting doc, as
below:

    $ time make htmldocs
    [...]
    Documentation/vm/damon/index.rst:24: WARNING: toctree contains reference to nonexisting document 'vm/damon/plans'

This fixes the warning by removing the wrong reference.

Link: https://lkml.kernel.org/r/20210917123958.3819-4-sj@kernel.org
Signed-off-by: SeongJae Park <sjpark@amazon.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06 13:30:44 -07:00
SeongJae Park ad782c48df Documentation/vm: move user guides to admin-guide/mm/
Most memory management user guide documents are in 'admin-guide/mm/',
but two of those are in 'vm/'.  This moves the two docs into
'admin-guide/mm' for easier documents finding.

Link: https://lkml.kernel.org/r/20210917123958.3819-2-sj@kernel.org
Signed-off-by: SeongJae Park <sjpark@amazon.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06 13:30:44 -07:00