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Author SHA1 Message Date
Qi Zheng
6dfd0d2cb3 mm: khugepaged: collapse_pte_mapped_thp() use pte_offset_map_rw_nolock() 
In collapse_pte_mapped_thp(), we may modify the pte and pmd entry after
acquiring the ptl, so convert it to using pte_offset_map_rw_nolock().  At
this time, the pte_same() check is not performed after the PTL held.  So
we should get pgt_pmd and do pmd_same() check after the ptl held.

Link: https://lkml.kernel.org/r/055e42db68da00ac8ecab94bd2633c7cd965eb1c.1727332572.git.zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-05 16:56:27 -08:00
Qi Zheng
c85507857b mm: khugepaged: __collapse_huge_page_swapin() use pte_offset_map_ro_nolock() 
In __collapse_huge_page_swapin(), we just use the ptl for pte_same() check
in do_swap_page().  In other places, we directly use
pte_offset_map_lock(), so convert it to using pte_offset_map_ro_nolock().

Link: https://lkml.kernel.org/r/dc97a6c3cb9ea80cab30c5626eeea79959d93258.1727332572.git.zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-05 16:56:27 -08:00
Nanyong Sun
f2f484085e mm: move mm flags to mm_types.h 
The types of mm flags are now far beyond the core dump related features. 
This patch moves mm flags from linux/sched/coredump.h to linux/mm_types.h.
The linux/sched/coredump.h has include the mm_types.h, so the C files
related to coredump does not need to change head file inclusion.  In
addition, the inclusion of sched/coredump.h now can be deleted from the C
files that irrelevant to core dump.

Link: https://lkml.kernel.org/r/20240926074922.2721274-1-sunnanyong@huawei.com
Signed-off-by: Nanyong Sun <sunnanyong@huawei.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-05 16:56:26 -08:00
Baolin Wang
d2d243df44 mm: shmem: fix khugepaged activation policy for shmem 
Shmem has a separate interface (different from anonymous pages) to control
huge page allocation, that means shmem THP can be enabled while anonymous
THP is disabled.  However, in this case, khugepaged will not start to
collapse shmem THP, which is unreasonable.

To fix this issue, we should call start_stop_khugepaged() to activate or
deactivate the khugepaged thread when setting shmem mTHP interfaces. 
Moreover, add a new helper shmem_hpage_pmd_enabled() to help to check
whether shmem THP is enabled, which will determine if khugepaged should be
activated.

Link: https://lkml.kernel.org/r/9b9c6cbc4499bf44c6455367fd9e0f6036525680.1726978977.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reported-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-05 16:56:20 -08:00
Baolin Wang
d60fcaf00d mm: khugepaged: fix the incorrect statistics when collapsing large file folios 
Khugepaged already supports collapsing file large folios (including shmem
mTHP) by commit 7de856ffd0 ("mm: khugepaged: support shmem mTHP
collapse"), and the control parameters in khugepaged:
'khugepaged_max_ptes_swap' and 'khugepaged_max_ptes_none', still compare
based on PTE granularity to determine whether a file collapse is needed. 
However, the statistics for 'present' and 'swap' in
hpage_collapse_scan_file() do not take into account the large folios,
which may lead to incorrect judgments regarding the
khugepaged_max_ptes_swap/none parameters, resulting in unnecessary file
collapses.

To fix this issue, take into account the large folios' statistics for
'present' and 'swap' variables in the hpage_collapse_scan_file().

Link: https://lkml.kernel.org/r/c76305d96d12d030a1a346b50503d148364246d2.1728901391.git.baolin.wang@linux.alibaba.com
Fixes: 7de856ffd0 ("mm: khugepaged: support shmem mTHP collapse")
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Barry Song <baohua@kernel.org>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-10-17 00:28:10 -07:00
Yang Shi
37f0b47c51 mm: khugepaged: fix the arguments order in khugepaged_collapse_file trace point 
The "addr" and "is_shmem" arguments have different order in TP_PROTO and
TP_ARGS.  This resulted in the incorrect trace result:

text-hugepage-644429 [276] 392092.878683: mm_khugepaged_collapse_file:
mm=0xffff20025d52c440, hpage_pfn=0x200678c00, index=512, addr=1, is_shmem=0,
filename=text-hugepage, nr=512, result=failed

The value of "addr" is wrong because it was treated as bool value, the
type of is_shmem.

Fix the order in TP_PROTO to keep "addr" is before "is_shmem" since the
original patch review suggested this order to achieve best packing.

And use "lx" for "addr" instead of "ld" in TP_printk because address is
typically shown in hex.

After the fix, the trace result looks correct:

text-hugepage-7291  [004]   128.627251: mm_khugepaged_collapse_file:
mm=0xffff0001328f9500, hpage_pfn=0x20016ea00, index=512, addr=0x400000,
is_shmem=0, filename=text-hugepage, nr=512, result=failed

Link: https://lkml.kernel.org/r/20241012011702.1084846-1-yang@os.amperecomputing.com
Fixes: 4c9473e87e ("mm/khugepaged: add tracepoint to collapse_file()")
Signed-off-by: Yang Shi <yang@os.amperecomputing.com>
Cc: Gautam Menghani <gautammenghani201@gmail.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: <stable@vger.kernel.org>    [6.2+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-10-17 00:28:09 -07:00
Rik van Riel
e1e4cfd01a mm,tmpfs: consider end of file write in shmem_is_huge 
Take the end of a file write into consideration when deciding whether or
not to use huge pages for tmpfs files when the tmpfs filesystem is mounted
with huge=within_size

This allows large writes that append to the end of a file to automatically
use large pages.

Doing 4MB sequential writes without fallocate to a 16GB tmpfs file with
fio.  The numbers without THP or with huge=always stay the same, but the
performance with huge=within_size now matches that of huge=always.

huge		before		after
4kB pages	1560 MB/s	1560 MB/s
within_size	1560 MB/s	4720 MB/s
always:		4720 MB/s	4720 MB/s

[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/20240903111928.7171e60c@imladris.surriel.com
Signed-off-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-09-09 16:39:12 -07:00
Usama Arif
dafff3f4c8 mm: split underused THPs 
This is an attempt to mitigate the issue of running out of memory when THP
is always enabled.  During runtime whenever a THP is being faulted in
(__do_huge_pmd_anonymous_page) or collapsed by khugepaged
(collapse_huge_page), the THP is added to _deferred_list.  Whenever memory
reclaim happens in linux, the kernel runs the deferred_split shrinker
which goes through the _deferred_list.

If the folio was partially mapped, the shrinker attempts to split it.  If
the folio is not partially mapped, the shrinker checks if the THP was
underused, i.e.  how many of the base 4K pages of the entire THP were
zero-filled.  If this number goes above a certain threshold (decided by
/sys/kernel/mm/transparent_hugepage/khugepaged/max_ptes_none), the
shrinker will attempt to split that THP.  Then at remap time, the pages
that were zero-filled are mapped to the shared zeropage, hence saving
memory.

Link: https://lkml.kernel.org/r/20240830100438.3623486-6-usamaarif642@gmail.com
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Suggested-by: Rik van Riel <riel@surriel.com>
Co-authored-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Alexander Zhu <alexlzhu@fb.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nico Pache <npache@redhat.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Shuang Zhai <zhais@google.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Shuang Zhai <szhai2@cs.rochester.edu>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-09-09 16:39:04 -07:00
Kefeng Wang
775d28fd45 mm: remove isolate_lru_page() 
There are no more callers of isolate_lru_page(), remove it.

[wangkefeng.wang@huawei.com: convert page to folio in comment and document, per Matthew]
  Link: https://lkml.kernel.org/r/20240826144114.1928071-1-wangkefeng.wang@huawei.com
Link: https://lkml.kernel.org/r/20240826065814.1336616-6-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-09-09 16:38:59 -07:00
Baolin Wang
7de856ffd0 mm: khugepaged: support shmem mTHP collapse 
Shmem already supports the allocation of mTHP, but khugepaged does not yet
support collapsing mTHP folios.  Now khugepaged is ready to support mTHP,
and this patch enables the collapse of shmem mTHP.

Link: https://lkml.kernel.org/r/b9da76aab4276eb6e5d12c479af2b5eea5b4575d.1724140601.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <21cnbao@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-09-03 21:15:39 -07:00
Baolin Wang
dfa98f56d9 mm: khugepaged: support shmem mTHP copy 
Iterate each subpage in the large folio to copy, as preparation for
supporting shmem mTHP collapse.

Link: https://lkml.kernel.org/r/222d615b7c837eabb47a238126c5fdeff8aa5283.1724140601.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <21cnbao@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-09-03 21:15:39 -07:00
Baolin Wang
d6b8f296e8 mm: khugepaged: use the number of pages in the folio to check the reference count 
Use the number of pages in the folio to check the reference count as
preparation for supporting shmem mTHP collapse.

Link: https://lkml.kernel.org/r/9ea49262308de28957596cc6e8edc2d3a4f54659.1724140601.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Barry Song <21cnbao@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-09-03 21:15:39 -07:00
Baolin Wang
fda6d4de06 mm: khugepaged: expand the is_refcount_suitable() to support file folios 
Patch series "support shmem mTHP collapse", v2.

Shmem already supports mTHP allocation[1], and this patchset adds support
for shmem mTHP collapse, as well as adding relevant test cases.


This patch (of 5):

Expand the is_refcount_suitable() to support reference checks for file
folios, as preparation for supporting shmem mTHP collapse.

Link: https://lkml.kernel.org/r/cover.1724140601.git.baolin.wang@linux.alibaba.com
Link: https://lkml.kernel.org/r/eae4cb3195ebbb654bfb7967cb7261d4e4e7c7fa.1724140601.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Barry Song <21cnbao@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-09-03 21:15:39 -07:00
Linus Torvalds
fbc90c042c - 875fa64577da ("mm/hugetlb_vmemmap: fix race with speculative PFN 
walkers") is known to cause a performance regression
   (https://lore.kernel.org/all/3acefad9-96e5-4681-8014-827d6be71c7a@linux.ibm.com/T/#mfa809800a7862fb5bdf834c6f71a3a5113eb83ff).
   Yu has a fix which I'll send along later via the hotfixes branch.
 
 - In the series "mm: Avoid possible overflows in dirty throttling" Jan
   Kara addresses a couple of issues in the writeback throttling code.
   These fixes are also targetted at -stable kernels.
 
 - Ryusuke Konishi's series "nilfs2: fix potential issues related to
   reserved inodes" does that.  This should actually be in the
   mm-nonmm-stable tree, along with the many other nilfs2 patches.  My bad.
 
 - More folio conversions from Kefeng Wang in the series "mm: convert to
   folio_alloc_mpol()"
 
 - Kemeng Shi has sent some cleanups to the writeback code in the series
   "Add helper functions to remove repeated code and improve readability of
   cgroup writeback"
 
 - Kairui Song has made the swap code a little smaller and a little
   faster in the series "mm/swap: clean up and optimize swap cache index".
 
 - In the series "mm/memory: cleanly support zeropage in
   vm_insert_page*(), vm_map_pages*() and vmf_insert_mixed()" David
   Hildenbrand has reworked the rather sketchy handling of the use of the
   zeropage in MAP_SHARED mappings.  I don't see any runtime effects here -
   more a cleanup/understandability/maintainablity thing.
 
 - Dev Jain has improved selftests/mm/va_high_addr_switch.c's handling of
   higher addresses, for aarch64.  The (poorly named) series is
   "Restructure va_high_addr_switch".
 
 - The core TLB handling code gets some cleanups and possible slight
   optimizations in Bang Li's series "Add update_mmu_tlb_range() to
   simplify code".
 
 - Jane Chu has improved the handling of our
   fake-an-unrecoverable-memory-error testing feature MADV_HWPOISON in the
   series "Enhance soft hwpoison handling and injection".
 
 - Jeff Johnson has sent a billion patches everywhere to add
   MODULE_DESCRIPTION() to everything.  Some landed in this pull.
 
 - In the series "mm: cleanup MIGRATE_SYNC_NO_COPY mode", Kefeng Wang has
   simplified migration's use of hardware-offload memory copying.
 
 - Yosry Ahmed performs more folio API conversions in his series "mm:
   zswap: trivial folio conversions".
 
 - In the series "large folios swap-in: handle refault cases first",
   Chuanhua Han inches us forward in the handling of large pages in the
   swap code.  This is a cleanup and optimization, working toward the end
   objective of full support of large folio swapin/out.
 
 - In the series "mm,swap: cleanup VMA based swap readahead window
   calculation", Huang Ying has contributed some cleanups and a possible
   fixlet to his VMA based swap readahead code.
 
 - In the series "add mTHP support for anonymous shmem" Baolin Wang has
   taught anonymous shmem mappings to use multisize THP.  By default this
   is a no-op - users must opt in vis sysfs controls.  Dramatic
   improvements in pagefault latency are realized.
 
 - David Hildenbrand has some cleanups to our remaining use of
   page_mapcount() in the series "fs/proc: move page_mapcount() to
   fs/proc/internal.h".
 
 - David also has some highmem accounting cleanups in the series
   "mm/highmem: don't track highmem pages manually".
 
 - Build-time fixes and cleanups from John Hubbard in the series
   "cleanups, fixes, and progress towards avoiding "make headers"".
 
 - Cleanups and consolidation of the core pagemap handling from Barry
   Song in the series "mm: introduce pmd|pte_needs_soft_dirty_wp helpers
   and utilize them".
 
 - Lance Yang's series "Reclaim lazyfree THP without splitting" has
   reduced the latency of the reclaim of pmd-mapped THPs under fairly
   common circumstances.  A 10x speedup is seen in a microbenchmark.
 
   It does this by punting to aother CPU but I guess that's a win unless
   all CPUs are pegged.
 
 - hugetlb_cgroup cleanups from Xiu Jianfeng in the series
   "mm/hugetlb_cgroup: rework on cftypes".
 
 - Miaohe Lin's series "Some cleanups for memory-failure" does just that
   thing.
 
 - Is anyone reading this stuff?  If so, email me!
 
 - Someone other than SeongJae has developed a DAMON feature in Honggyu
   Kim's series "DAMON based tiered memory management for CXL memory".
   This adds DAMON features which may be used to help determine the
   efficiency of our placement of CXL/PCIe attached DRAM.
 
 - DAMON user API centralization and simplificatio work in SeongJae
   Park's series "mm/damon: introduce DAMON parameters online commit
   function".
 
 - In the series "mm: page_type, zsmalloc and page_mapcount_reset()"
   David Hildenbrand does some maintenance work on zsmalloc - partially
   modernizing its use of pageframe fields.
 
 - Kefeng Wang provides more folio conversions in the series "mm: remove
   page_maybe_dma_pinned() and page_mkclean()".
 
 - More cleanup from David Hildenbrand, this time in the series
   "mm/memory_hotplug: use PageOffline() instead of PageReserved() for
   !ZONE_DEVICE".  It "enlightens memory hotplug more about PageOffline()
   pages" and permits the removal of some virtio-mem hacks.
 
 - Barry Song's series "mm: clarify folio_add_new_anon_rmap() and
   __folio_add_anon_rmap()" is a cleanup to the anon folio handling in
   preparation for mTHP (multisize THP) swapin.
 
 - Kefeng Wang's series "mm: improve clear and copy user folio"
   implements more folio conversions, this time in the area of large folio
   userspace copying.
 
 - The series "Docs/mm/damon/maintaier-profile: document a mailing tool
   and community meetup series" tells people how to get better involved
   with other DAMON developers.  From SeongJae Park.
 
 - A large series ("kmsan: Enable on s390") from Ilya Leoshkevich does
   that.
 
 - David Hildenbrand sends along more cleanups, this time against the
   migration code.  The series is "mm/migrate: move NUMA hinting fault
   folio isolation + checks under PTL".
 
 - Jan Kara has found quite a lot of strangenesses and minor errors in
   the readahead code.  He addresses this in the series "mm: Fix various
   readahead quirks".
 
 - SeongJae Park's series "selftests/damon: test DAMOS tried regions and
   {min,max}_nr_regions" adds features and addresses errors in DAMON's self
   testing code.
 
 - Gavin Shan has found a userspace-triggerable WARN in the pagecache
   code.  The series "mm/filemap: Limit page cache size to that supported
   by xarray" addresses this.  The series is marked cc:stable.
 
 - Chengming Zhou's series "mm/ksm: cmp_and_merge_page() optimizations
   and cleanup" cleans up and slightly optimizes KSM.
 
 - Roman Gushchin has separated the memcg-v1 and memcg-v2 code - lots of
   code motion.  The series (which also makes the memcg-v1 code
   Kconfigurable) are
 
   "mm: memcg: separate legacy cgroup v1 code and put under config
   option" and
   "mm: memcg: put cgroup v1-specific memcg data under CONFIG_MEMCG_V1"
 
 - Dan Schatzberg's series "Add swappiness argument to memory.reclaim"
   adds an additional feature to this cgroup-v2 control file.
 
 - The series "Userspace controls soft-offline pages" from Jiaqi Yan
   permits userspace to stop the kernel's automatic treatment of excessive
   correctable memory errors.  In order to permit userspace to monitor and
   handle this situation.
 
 - Kefeng Wang's series "mm: migrate: support poison recover from migrate
   folio" teaches the kernel to appropriately handle migration from
   poisoned source folios rather than simply panicing.
 
 - SeongJae Park's series "Docs/damon: minor fixups and improvements"
   does those things.
 
 - In the series "mm/zsmalloc: change back to per-size_class lock"
   Chengming Zhou improves zsmalloc's scalability and memory utilization.
 
 - Vivek Kasireddy's series "mm/gup: Introduce memfd_pin_folios() for
   pinning memfd folios" makes the GUP code use FOLL_PIN rather than bare
   refcount increments.  So these paes can first be moved aside if they
   reside in the movable zone or a CMA block.
 
 - Andrii Nakryiko has added a binary ioctl()-based API to /proc/pid/maps
   for much faster reading of vma information.  The series is "query VMAs
   from /proc/<pid>/maps".
 
 - In the series "mm: introduce per-order mTHP split counters" Lance Yang
   improves the kernel's presentation of developer information related to
   multisize THP splitting.
 
 - Michael Ellerman has developed the series "Reimplement huge pages
   without hugepd on powerpc (8xx, e500, book3s/64)".  This permits
   userspace to use all available huge page sizes.
 
 - In the series "revert unconditional slab and page allocator fault
   injection calls" Vlastimil Babka removes a performance-affecting and not
   very useful feature from slab fault injection.
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Merge tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - In the series "mm: Avoid possible overflows in dirty throttling" Jan
   Kara addresses a couple of issues in the writeback throttling code.
   These fixes are also targetted at -stable kernels.

 - Ryusuke Konishi's series "nilfs2: fix potential issues related to
   reserved inodes" does that. This should actually be in the
   mm-nonmm-stable tree, along with the many other nilfs2 patches. My
   bad.

 - More folio conversions from Kefeng Wang in the series "mm: convert to
   folio_alloc_mpol()"

 - Kemeng Shi has sent some cleanups to the writeback code in the series
   "Add helper functions to remove repeated code and improve readability
   of cgroup writeback"

 - Kairui Song has made the swap code a little smaller and a little
   faster in the series "mm/swap: clean up and optimize swap cache
   index".

 - In the series "mm/memory: cleanly support zeropage in
   vm_insert_page*(), vm_map_pages*() and vmf_insert_mixed()" David
   Hildenbrand has reworked the rather sketchy handling of the use of
   the zeropage in MAP_SHARED mappings. I don't see any runtime effects
   here - more a cleanup/understandability/maintainablity thing.

 - Dev Jain has improved selftests/mm/va_high_addr_switch.c's handling
   of higher addresses, for aarch64. The (poorly named) series is
   "Restructure va_high_addr_switch".

 - The core TLB handling code gets some cleanups and possible slight
   optimizations in Bang Li's series "Add update_mmu_tlb_range() to
   simplify code".

 - Jane Chu has improved the handling of our
   fake-an-unrecoverable-memory-error testing feature MADV_HWPOISON in
   the series "Enhance soft hwpoison handling and injection".

 - Jeff Johnson has sent a billion patches everywhere to add
   MODULE_DESCRIPTION() to everything. Some landed in this pull.

 - In the series "mm: cleanup MIGRATE_SYNC_NO_COPY mode", Kefeng Wang
   has simplified migration's use of hardware-offload memory copying.

 - Yosry Ahmed performs more folio API conversions in his series "mm:
   zswap: trivial folio conversions".

 - In the series "large folios swap-in: handle refault cases first",
   Chuanhua Han inches us forward in the handling of large pages in the
   swap code. This is a cleanup and optimization, working toward the end
   objective of full support of large folio swapin/out.

 - In the series "mm,swap: cleanup VMA based swap readahead window
   calculation", Huang Ying has contributed some cleanups and a possible
   fixlet to his VMA based swap readahead code.

 - In the series "add mTHP support for anonymous shmem" Baolin Wang has
   taught anonymous shmem mappings to use multisize THP. By default this
   is a no-op - users must opt in vis sysfs controls. Dramatic
   improvements in pagefault latency are realized.

 - David Hildenbrand has some cleanups to our remaining use of
   page_mapcount() in the series "fs/proc: move page_mapcount() to
   fs/proc/internal.h".

 - David also has some highmem accounting cleanups in the series
   "mm/highmem: don't track highmem pages manually".

 - Build-time fixes and cleanups from John Hubbard in the series
   "cleanups, fixes, and progress towards avoiding "make headers"".

 - Cleanups and consolidation of the core pagemap handling from Barry
   Song in the series "mm: introduce pmd|pte_needs_soft_dirty_wp helpers
   and utilize them".

 - Lance Yang's series "Reclaim lazyfree THP without splitting" has
   reduced the latency of the reclaim of pmd-mapped THPs under fairly
   common circumstances. A 10x speedup is seen in a microbenchmark.

   It does this by punting to aother CPU but I guess that's a win unless
   all CPUs are pegged.

 - hugetlb_cgroup cleanups from Xiu Jianfeng in the series
   "mm/hugetlb_cgroup: rework on cftypes".

 - Miaohe Lin's series "Some cleanups for memory-failure" does just that
   thing.

 - Someone other than SeongJae has developed a DAMON feature in Honggyu
   Kim's series "DAMON based tiered memory management for CXL memory".
   This adds DAMON features which may be used to help determine the
   efficiency of our placement of CXL/PCIe attached DRAM.

 - DAMON user API centralization and simplificatio work in SeongJae
   Park's series "mm/damon: introduce DAMON parameters online commit
   function".

 - In the series "mm: page_type, zsmalloc and page_mapcount_reset()"
   David Hildenbrand does some maintenance work on zsmalloc - partially
   modernizing its use of pageframe fields.

 - Kefeng Wang provides more folio conversions in the series "mm: remove
   page_maybe_dma_pinned() and page_mkclean()".

 - More cleanup from David Hildenbrand, this time in the series
   "mm/memory_hotplug: use PageOffline() instead of PageReserved() for
   !ZONE_DEVICE". It "enlightens memory hotplug more about PageOffline()
   pages" and permits the removal of some virtio-mem hacks.

 - Barry Song's series "mm: clarify folio_add_new_anon_rmap() and
   __folio_add_anon_rmap()" is a cleanup to the anon folio handling in
   preparation for mTHP (multisize THP) swapin.

 - Kefeng Wang's series "mm: improve clear and copy user folio"
   implements more folio conversions, this time in the area of large
   folio userspace copying.

 - The series "Docs/mm/damon/maintaier-profile: document a mailing tool
   and community meetup series" tells people how to get better involved
   with other DAMON developers. From SeongJae Park.

 - A large series ("kmsan: Enable on s390") from Ilya Leoshkevich does
   that.

 - David Hildenbrand sends along more cleanups, this time against the
   migration code. The series is "mm/migrate: move NUMA hinting fault
   folio isolation + checks under PTL".

 - Jan Kara has found quite a lot of strangenesses and minor errors in
   the readahead code. He addresses this in the series "mm: Fix various
   readahead quirks".

 - SeongJae Park's series "selftests/damon: test DAMOS tried regions and
   {min,max}_nr_regions" adds features and addresses errors in DAMON's
   self testing code.

 - Gavin Shan has found a userspace-triggerable WARN in the pagecache
   code. The series "mm/filemap: Limit page cache size to that supported
   by xarray" addresses this. The series is marked cc:stable.

 - Chengming Zhou's series "mm/ksm: cmp_and_merge_page() optimizations
   and cleanup" cleans up and slightly optimizes KSM.

 - Roman Gushchin has separated the memcg-v1 and memcg-v2 code - lots of
   code motion. The series (which also makes the memcg-v1 code
   Kconfigurable) are "mm: memcg: separate legacy cgroup v1 code and put
   under config option" and "mm: memcg: put cgroup v1-specific memcg
   data under CONFIG_MEMCG_V1"

 - Dan Schatzberg's series "Add swappiness argument to memory.reclaim"
   adds an additional feature to this cgroup-v2 control file.

 - The series "Userspace controls soft-offline pages" from Jiaqi Yan
   permits userspace to stop the kernel's automatic treatment of
   excessive correctable memory errors. In order to permit userspace to
   monitor and handle this situation.

 - Kefeng Wang's series "mm: migrate: support poison recover from
   migrate folio" teaches the kernel to appropriately handle migration
   from poisoned source folios rather than simply panicing.

 - SeongJae Park's series "Docs/damon: minor fixups and improvements"
   does those things.

 - In the series "mm/zsmalloc: change back to per-size_class lock"
   Chengming Zhou improves zsmalloc's scalability and memory
   utilization.

 - Vivek Kasireddy's series "mm/gup: Introduce memfd_pin_folios() for
   pinning memfd folios" makes the GUP code use FOLL_PIN rather than
   bare refcount increments. So these paes can first be moved aside if
   they reside in the movable zone or a CMA block.

 - Andrii Nakryiko has added a binary ioctl()-based API to
   /proc/pid/maps for much faster reading of vma information. The series
   is "query VMAs from /proc/<pid>/maps".

 - In the series "mm: introduce per-order mTHP split counters" Lance
   Yang improves the kernel's presentation of developer information
   related to multisize THP splitting.

 - Michael Ellerman has developed the series "Reimplement huge pages
   without hugepd on powerpc (8xx, e500, book3s/64)". This permits
   userspace to use all available huge page sizes.

 - In the series "revert unconditional slab and page allocator fault
   injection calls" Vlastimil Babka removes a performance-affecting and
   not very useful feature from slab fault injection.

* tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (411 commits)
  mm/mglru: fix ineffective protection calculation
  mm/zswap: fix a white space issue
  mm/hugetlb: fix kernel NULL pointer dereference when migrating hugetlb folio
  mm/hugetlb: fix possible recursive locking detected warning
  mm/gup: clear the LRU flag of a page before adding to LRU batch
  mm/numa_balancing: teach mpol_to_str about the balancing mode
  mm: memcg1: convert charge move flags to unsigned long long
  alloc_tag: fix page_ext_get/page_ext_put sequence during page splitting
  lib: reuse page_ext_data() to obtain codetag_ref
  lib: add missing newline character in the warning message
  mm/mglru: fix overshooting shrinker memory
  mm/mglru: fix div-by-zero in vmpressure_calc_level()
  mm/kmemleak: replace strncpy() with strscpy()
  mm, page_alloc: put should_fail_alloc_page() back behing CONFIG_FAIL_PAGE_ALLOC
  mm, slab: put should_failslab() back behind CONFIG_SHOULD_FAILSLAB
  mm: ignore data-race in __swap_writepage
  hugetlbfs: ensure generic_hugetlb_get_unmapped_area() returns higher address than mmap_min_addr
  mm: shmem: rename mTHP shmem counters
  mm: swap_state: use folio_alloc_mpol() in __read_swap_cache_async()
  mm/migrate: putback split folios when numa hint migration fails
  ...
 2024-07-21 17:15:46 -07:00
Ryan Roberts
00f5810420 mm: fix khugepaged activation policy 
Since the introduction of mTHP, the docuementation has stated that
khugepaged would be enabled when any mTHP size is enabled, and disabled
when all mTHP sizes are disabled.  There are 2 problems with this; 1. 
this is not what was implemented by the code and 2.  this is not the
desirable behavior.

Desirable behavior is for khugepaged to be enabled when any PMD-sized THP
is enabled, anon or file.  (Note that file THP is still controlled by the
top-level control so we must always consider that, as well as the PMD-size
mTHP control for anon).  khugepaged only supports collapsing to PMD-sized
THP so there is no value in enabling it when PMD-sized THP is disabled. 
So let's change the code and documentation to reflect this policy.

Further, per-size enabled control modification events were not previously
forwarded to khugepaged to give it an opportunity to start or stop. 
Consequently the following was resulting in khugepaged eroneously not
being activated:

  echo never > /sys/kernel/mm/transparent_hugepage/enabled
  echo always > /sys/kernel/mm/transparent_hugepage/hugepages-2048kB/enabled

[ryan.roberts@arm.com: v3]
  Link: https://lkml.kernel.org/r/20240705102849.2479686-1-ryan.roberts@arm.com
Link: https://lkml.kernel.org/r/20240705102849.2479686-1-ryan.roberts@arm.com
Link: https://lkml.kernel.org/r/20240704091051.2411934-1-ryan.roberts@arm.com
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Fixes: 3485b88390 ("mm: thp: introduce multi-size THP sysfs interface")
Closes: https://lore.kernel.org/linux-mm/7a0bbe69-1e3d-4263-b206-da007791a5c4@redhat.com/
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lance Yang <ioworker0@gmail.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-07-12 15:52:20 -07:00
Barry Song
15bde4abab mm: extend rmap flags arguments for folio_add_new_anon_rmap 
Patch series "mm: clarify folio_add_new_anon_rmap() and
__folio_add_anon_rmap()", v2.

This patchset is preparatory work for mTHP swapin.

folio_add_new_anon_rmap() assumes that new anon rmaps are always
exclusive.  However, this assumption doesn’t hold true for cases like
do_swap_page(), where a new anon might be added to the swapcache and is
not necessarily exclusive.

The patchset extends the rmap flags to allow folio_add_new_anon_rmap() to
handle both exclusive and non-exclusive new anon folios.  The
do_swap_page() function is updated to use this extended API with rmap
flags.  Consequently, all new anon folios now consistently use
folio_add_new_anon_rmap().  The special case for !folio_test_anon() in
__folio_add_anon_rmap() can be safely removed.

In conclusion, new anon folios always use folio_add_new_anon_rmap(),
regardless of exclusivity.  Old anon folios continue to use
__folio_add_anon_rmap() via folio_add_anon_rmap_pmd() and
folio_add_anon_rmap_ptes().


This patch (of 3):

In the case of a swap-in, a new anonymous folio is not necessarily
exclusive.  This patch updates the rmap flags to allow a new anonymous
folio to be treated as either exclusive or non-exclusive.  To maintain the
existing behavior, we always use EXCLUSIVE as the default setting.

[akpm@linux-foundation.org: cleanup and constifications per David and akpm]
[v-songbaohua@oppo.com: fix missing doc for flags of folio_add_new_anon_rmap()]
  Link: https://lkml.kernel.org/r/20240619210641.62542-1-21cnbao@gmail.com
[v-songbaohua@oppo.com: enhance doc for extend rmap flags arguments for folio_add_new_anon_rmap]
  Link: https://lkml.kernel.org/r/20240622030256.43775-1-21cnbao@gmail.com
Link: https://lkml.kernel.org/r/20240617231137.80726-1-21cnbao@gmail.com
Link: https://lkml.kernel.org/r/20240617231137.80726-2-21cnbao@gmail.com
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Tested-by: Shuai Yuan <yuanshuai@oppo.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-07-03 19:30:18 -07:00
Hongfu Li
9b94b5a2f9 khugepaged: simplify the allocation of slab caches 
Use the new KMEM_CACHE() macro instead of direct kmem_cache_create
to simplify the creation of SLAB caches.

Link: https://lkml.kernel.org/r/20240618014517.25954-1-lihongfu@kylinos.cn
Signed-off-by: Hongfu Li <lihongfu@kylinos.cn>
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-07-03 19:30:15 -07:00
Mateusz Guzik
8e3447822d
vfs: remove redundant smp_mb for thp handling in do_dentry_open 
opening for write performs:

if (f->f_mode & FMODE_WRITE) {
[snip]
        smp_mb();
        if (filemap_nr_thps(inode->i_mapping)) {
[snip]
        }
}

filemap_nr_thps on kernels built without CONFIG_READ_ONLY_THP_FOR
expands to 0, allowing the compiler to eliminate the entire thing, with
exception of the fence (and the branch leading there).

So happens required synchronisation between i_writecount and nr_thps
changes is already provided by the full fence coming from
get_write_access -> atomic_inc_unless_negative, thus the smp_mb instance
above can be removed regardless of CONFIG_READ_ONLY_THP_FOR.

While I updated commentary in places claiming to match the now-removed
fence, I did not try to patch them to act on the compile option.

I did not bother benchmarking it, not issuing a spurious full fence in
the fast path does not warrant justification from perf standpoint.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/r/20240624085402.493630-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
 2024-06-25 11:15:48 +02:00
Matthew Wilcox
e0ffb29bc5 mm: simplify thp_vma_allowable_order 
Combine the three boolean arguments into one flags argument for
readability.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-05-05 17:53:53 -07:00
David Hildenbrand
1bafe96e89 mm/khugepaged: replace page_mapcount() check by folio_likely_mapped_shared() 
We want to limit the use of page_mapcount() to places where absolutely
required, to prepare for kernel configs where we won't keep track of
per-page mapcounts in large folios.

khugepaged is one of the remaining "more challenging" page_mapcount()
users, but we might be able to move away from page_mapcount() without
resulting in a significant behavior change that would warrant
special-casing based on kernel configs.

In 2020, we first added support to khugepaged for collapsing COW-shared
pages via commit 9445689f3b ("khugepaged: allow to collapse a page
shared across fork"), followed by support for collapsing PTE-mapped THP in
commit 5503fbf2b0 ("khugepaged: allow to collapse PTE-mapped compound
pages") and limiting the memory waste via the "page_count() > 1" check in
commit 71a2c112a0 ("khugepaged: introduce 'max_ptes_shared' tunable").

As a default, khugepaged will allow up to half of the PTEs to map shared
pages: where page_mapcount() > 1.  MADV_COLLAPSE ignores the khugepaged
setting.

khugepaged does currently not care about swapcache page references, and
does not check under folio lock: so in some corner cases the "shared vs. 
exclusive" detection might be a bit off, making us detect "exclusive" when
it's actually "shared".

Most of our anonymous folios in the system are usually exclusive.  We
frequently see sharing of anonymous folios for a short period of time,
after which our short-lived suprocesses either quit or exec().

There are some famous examples, though, where child processes exist for a
long time, and where memory is COW-shared with a lot of processes
(webservers, webbrowsers, sshd, ...) and COW-sharing is crucial for
reducing the memory footprint.  We don't want to suddenly change the
behavior to result in a significant increase in memory waste.

Interestingly, khugepaged will only collapse an anonymous THP if at least
one PTE is writable.  After fork(), that means that something (usually a
page fault) populated at least a single exclusive anonymous THP in that
PMD range.

So ...  what happens when we switch to "is this folio mapped shared"
instead of "is this page mapped shared" by using
folio_likely_mapped_shared()?

For "not-COW-shared" folios, small folios and for THPs (large folios) that
are completely mapped into at least one process, switching to
folio_likely_mapped_shared() will not result in a change.

We'll only see a change for COW-shared PTE-mapped THPs that are partially
mapped into all involved processes.

There are two cases to consider:

(A) folio_likely_mapped_shared() returns "false" for a PTE-mapped THP

  If the folio is detected as exclusive, and it actually is exclusive,
  there is no change: page_mapcount() == 1. This is the common case
  without fork() or with short-lived child processes.

  folio_likely_mapped_shared() might currently still detect a folio as
  exclusive although it is shared (false negatives): if the first page is
  not mapped multiple times and if the average per-page mapcount is smaller
  than 1, implying that (1) the folio is partially mapped and (2) if we are
  responsible for many mapcounts by mapping many pages others can't
  ("mostly exclusive") (3) if we are not responsible for many mapcounts by
  mapping little pages ("mostly shared") it won't make a big impact on the
  end result.

  So while we might now detect a page as "exclusive" although it isn't,
  it's not expected to make a big difference in common cases.

(B) folio_likely_mapped_shared() returns "true" for a PTE-mapped THP

  folio_likely_mapped_shared() will never detect a large anonymous folio
  as shared although it is exclusive: there are no false positives.

  If we detect a THP as shared, at least one page of the THP is mapped by
  another process. It could well be that some pages are actually exclusive.
  For example, our child processes could have unmapped/COW'ed some pages
  such that they would now be exclusive to out process, which we now
  would treat as still-shared.

  Examples:
  (1) Parent maps all pages of a THP, child maps some pages. We detect
      all pages in the parent as shared although some are actually
      exclusive.
  (2) Parent maps all but some page of a THP, child maps the remainder.
      We detect all pages of the THP that the parent maps as shared
      although they are all exclusive.

  In (1) we wouldn't collapse a THP right now already: no PTE
  is writable, because a write fault would have resulted in COW of a
  single page and the parent would no longer map all pages of that THP.

  For (2) we would have collapsed a THP in the parent so far, now we
  wouldn't as long as the child process is still alive: unless the child
  process unmaps the remaining THP pages or we decide to split that THP.

  Possibly, the child COW'ed many pages, meaning that it's likely that
  we can populate a THP for our child first, and then for our parent.

  For (2), we are making really bad use of the THP in the first
  place (not even mapped completely in at least one process). If the
  THP would be completely partially mapped, it would be on the deferred
  split queue where we would split it lazily later.

  For short-running child processes, we don't particularly care. For
  long-running processes, the expectation is that such scenarios are
  rather rare: further, a THP might be best placed if most data in the
  PMD range is actually written, implying that we'll have to COW more
  pages first before khugepaged would collapse it.

To summarize, in the common case, this change is not expected to matter
much.  The more common application of khugepaged operates on exclusive
pages, either before fork() or after a child quit.

Can we improve (A)?  Yes, if we implement more precise tracking of "mapped
shared" vs.  "mapped exclusively", we could get rid of the false negatives
completely.

Can we improve (B)?  We could count how many pages of a large folio we map
inside the current page table and detect that we are responsible for most
of the folio mapcount and conclude "as good as exclusive", which might
help in some cases.  ...  but likely, some other mechanism should detect
that the THP is not a good use in the scenario (not even mapped completely
in a single process) and try splitting that folio lazily etc.

We'll move the folio_test_anon() check before our "shared" check, so we
might get more expressive results for SCAN_EXCEED_SHARED_PTE: this order
of checks now matches the one in __collapse_huge_page_isolate().  Extend
documentation.

Link: https://lkml.kernel.org/r/20240424122630.495788-1-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-05-05 17:53:50 -07:00
David Hildenbrand
05c5323b2a mm: track mapcount of large folios in single value 
Let's track the mapcount of large folios in a single value.  The mapcount
of a large folio currently corresponds to the sum of the entire mapcount
and all page mapcounts.

This sum is what we actually want to know in folio_mapcount() and it is
also sufficient for implementing folio_mapped().

With PTE-mapped THP becoming more important and more widely used, we want
to avoid looping over all pages of a folio just to obtain the mapcount of
large folios.  The comment "In the common case, avoid the loop when no
pages mapped by PTE" in folio_total_mapcount() does no longer hold for
mTHP that are always mapped by PTE.

Further, we are planning on using folio_mapcount() more frequently, and
might even want to remove page mapcounts for large folios in some kernel
configs.  Therefore, allow for reading the mapcount of large folios
efficiently and atomically without looping over any pages.

Maintain the mapcount also for hugetlb pages for simplicity.  Use the new
mapcount to implement folio_mapcount() and folio_mapped().  Make
page_mapped() simply call folio_mapped().  We can now get rid of
folio_large_is_mapped().

_nr_pages_mapped is now only used in rmap code and for debugging purposes.
Keep folio_nr_pages_mapped() around, but document that its use should be
limited to rmap internals and debugging purposes.

This change implies one additional atomic add/sub whenever
mapping/unmapping (parts of) a large folio.

As we now batch RMAP operations for PTE-mapped THP during fork(), during
unmap/zap, and when PTE-remapping a PMD-mapped THP, and we adjust the
large mapcount for a PTE batch only once, the added overhead in the common
case is small.  Only when unmapping individual pages of a large folio
(e.g., during COW), the overhead might be bigger in comparison, but it's
essentially one additional atomic operation.

Note that before the new mapcount would overflow, already our refcount
would overflow: each mapping requires a folio reference.  Extend the
focumentation of folio_mapcount().

Link: https://lkml.kernel.org/r/20240409192301.907377-5-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Yin Fengwei <fengwei.yin@intel.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Richard Chang <richardycc@google.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-05-05 17:53:28 -07:00
David Hildenbrand
0ae0b2b325 mm: use "GUP-fast" instead "fast GUP" in remaining comments 
Let's fixup the remaining comments to consistently call that thing
"GUP-fast".  With this change, we consistently call it "GUP-fast".

Link: https://lkml.kernel.org/r/20240402125516.223131-4-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-04-25 20:56:41 -07:00
Matthew Wilcox (Oracle)
43849758fd khugepaged: use a folio throughout hpage_collapse_scan_file() 
Replace the use of pages with folios.  Saves a few calls to
compound_head() and removes some uses of obsolete functions.

Link: https://lkml.kernel.org/r/20240403171838.1445826-8-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-04-25 20:56:34 -07:00
Matthew Wilcox (Oracle)
8d1e24c0b8 khugepaged: use a folio throughout collapse_file() 
Pull folios from the page cache instead of pages.  Half of this work had
been done already, but we were still operating on pages for a large chunk
of this function.  There is no attempt in this patch to handle large
folios that are smaller than a THP; that will have to wait for a future
patch.

[willy@infradead.org: the unlikely() is embedded in IS_ERR()]
  Link: https://lkml.kernel.org/r/ZhIWX8K0E2tSyMSr@casper.infradead.org
Link: https://lkml.kernel.org/r/20240403171838.1445826-7-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-04-25 20:56:34 -07:00
Matthew Wilcox (Oracle)
610ff817b9 khugepaged: remove hpage from collapse_file() 
Use new_folio throughout where we had been using hpage.

Link: https://lkml.kernel.org/r/20240403171838.1445826-6-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-04-25 20:56:33 -07:00
Matthew Wilcox (Oracle)
8eca68e2cf khugepaged: pass a folio to __collapse_huge_page_copy() 
Simplify the body of __collapse_huge_page_copy() while I'm looking at
it.

Link: https://lkml.kernel.org/r/20240403171838.1445826-5-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-04-25 20:56:33 -07:00
Matthew Wilcox (Oracle)
0234779276 khugepaged: remove hpage from collapse_huge_page() 
Work purely in terms of the folio.  Removes a call to compound_head()
in put_page().

Link: https://lkml.kernel.org/r/20240403171838.1445826-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-04-25 20:56:33 -07:00
Matthew Wilcox (Oracle)
d5ab50b941 khugepaged: convert alloc_charge_hpage to alloc_charge_folio 
Both callers want to deal with a folio, so return a folio from this
function.

Link: https://lkml.kernel.org/r/20240403171838.1445826-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-04-25 20:56:33 -07:00
Matthew Wilcox (Oracle)
4746f5ce0f khugepaged: inline hpage_collapse_alloc_folio() 
Patch series "khugepaged folio conversions".

We've been kind of hacking piecemeal at converting khugepaged to use
folios instead of compound pages, and so this patchset is a little larger
than it should be as I undo some of our wrong moves in the past.  In
particular, collapse_file() now consistently uses 'new_folio' for the
freshly allocated folio and 'folio' for the one that's currently in use.  


This patch (of 7):

This function has one caller, and the combined function is simpler to
read, reason about and modify.

Link: https://lkml.kernel.org/r/20240403171838.1445826-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20240403171838.1445826-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> 
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-04-25 20:56:32 -07:00
Matthew Wilcox (Oracle)
63b774993d mm: convert free_swap_cache() to take a folio 
All but one caller already has a folio, so convert
free_page_and_swap_cache() to have a folio and remove the call to
page_folio().

Link: https://lkml.kernel.org/r/20240227174254.710559-19-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-03-04 17:01:26 -08:00
Matthew Wilcox (Oracle)
d4111eecdc mm: use a folio in __collapse_huge_page_copy_succeeded() 
These pages are all chained together through the lru list, so we know
they're folios.  Use the folio APIs to save three hidden calls to
compound_head().

Link: https://lkml.kernel.org/r/20240227174254.710559-18-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-03-04 17:01:26 -08:00
Lance Yang
5dad604809 mm/khugepaged: keep mm in mm_slot without MMF_DISABLE_THP check 
Previously, we removed the mm from mm_slot and dropped mm_count
if the MMF_THP_DISABLE flag was set. However, we didn't re-add
the mm back after clearing the MMF_THP_DISABLE flag. Additionally,
We add a check for the MMF_THP_DISABLE flag in hugepage_vma_revalidate().

Link: https://lkml.kernel.org/r/20240227035135.54593-1-ioworker0@gmail.com
Fixes: 879c6000e1 ("mm/khugepaged: bypassing unnecessary scans with MMF_DISABLE_THP check")
Signed-off-by: Lance Yang <ioworker0@gmail.com>
Suggested-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-03-04 17:01:22 -08:00
Lance Yang
879c6000e1 mm/khugepaged: bypassing unnecessary scans with MMF_DISABLE_THP check 
khugepaged scans the entire address space in the background for each
given mm, looking for opportunities to merge sequences of basic pages
into huge pages.  However, when an mm is inserted to the mm_slots list,
and the MMF_DISABLE_THP flag is set later, this scanning process
becomes unnecessary for that mm and can be skipped to avoid redundant
operations, especially in scenarios with a large address space.

On an Intel Core i5 CPU, the time taken by khugepaged to scan the
address space of the process, which has been set with the
MMF_DISABLE_THP flag after being added to the mm_slots list, is as
follows (shorter is better):

VMA Count |   Old   |   New   |  Change
---------------------------------------
    50    |   23us  |    9us  |  -60.9%
   100    |   32us  |    9us  |  -71.9%
   200    |   44us  |    9us  |  -79.5%
   400    |   75us  |    9us  |  -88.0%
   800    |   98us  |    9us  |  -90.8%

Once the count of VMAs for the process exceeds page_to_scan, khugepaged
needs to wait for scan_sleep_millisecs ms before scanning the next
process.  IMO, unnecessary scans could actually be skipped with a very
inexpensive mm->flags check in this case.

This commit introduces a check before each scanning process to test the
MMF_DISABLE_THP flag for the given mm; if the flag is set, the scanning
process is bypassed, thereby improving the efficiency of khugepaged.

This optimization is not a correctness issue but rather an enhancement
to save expensive checks on each VMA when userspace cannot prctl itself
before spawning into the new process.

On some servers within our company, we deploy a daemon responsible for
monitoring and updating local applications.  Some applications prefer
not to use THP, so the daemon calls prctl to disable THP before
fork/exec.  Conversely, for other applications, the daemon calls prctl
to enable THP before fork/exec.

Ideally, the daemon should invoke prctl after the fork, but its current
implementation follows the described approach.  In the Go standard
library, there is no direct encapsulation of the fork system call;
instead, fork and execve are combined into one through
syscall.ForkExec.

Link: https://lkml.kernel.org/r/20240129054551.57728-1-ioworker0@gmail.com
Signed-off-by: Lance Yang <ioworker0@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-02-23 17:48:25 -08:00
Kefeng Wang
6b27cc6c66 mm: convert mm_counter_file() to take a folio 
Now all callers of mm_counter_file() have a folio, convert
mm_counter_file() to take a folio.  Saves a call to compound_head() hidden
inside PageSwapBacked().

Link: https://lkml.kernel.org/r/20240111152429.3374566-11-willy@infradead.org
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-02-21 16:00:04 -08:00
Linus Torvalds
78273df7f6 header cleanups for 6.8 
The goal is to get sched.h down to a type only header, so the main thing
 happening in this patchset is splitting out various _types.h headers and
 dependency fixups, as well as moving some things out of sched.h to
 better locations.
 
 This is prep work for the memory allocation profiling patchset which
 adds new sched.h interdepencencies.
 
 Testing - it's been in -next, and fixes from pretty much all
 architectures have percolated in - nothing major.
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Merge tag 'header_cleanup-2024-01-10' of https://evilpiepirate.org/git/bcachefs

Pull header cleanups from Kent Overstreet:
 "The goal is to get sched.h down to a type only header, so the main
  thing happening in this patchset is splitting out various _types.h
  headers and dependency fixups, as well as moving some things out of
  sched.h to better locations.

  This is prep work for the memory allocation profiling patchset which
  adds new sched.h interdepencencies"

* tag 'header_cleanup-2024-01-10' of https://evilpiepirate.org/git/bcachefs: (51 commits)
  Kill sched.h dependency on rcupdate.h
  kill unnecessary thread_info.h include
  Kill unnecessary kernel.h include
  preempt.h: Kill dependency on list.h
  rseq: Split out rseq.h from sched.h
  LoongArch: signal.c: add header file to fix build error
  restart_block: Trim includes
  lockdep: move held_lock to lockdep_types.h
  sem: Split out sem_types.h
  uidgid: Split out uidgid_types.h
  seccomp: Split out seccomp_types.h
  refcount: Split out refcount_types.h
  uapi/linux/resource.h: fix include
  x86/signal: kill dependency on time.h
  syscall_user_dispatch.h: split out *_types.h
  mm_types_task.h: Trim dependencies
  Split out irqflags_types.h
  ipc: Kill bogus dependency on spinlock.h
  shm: Slim down dependencies
  workqueue: Split out workqueue_types.h
  ...
 2024-01-10 16:43:55 -08:00
Matthew Wilcox (Oracle)
b54d60b18e mm/khugepaged: use a folio more in collapse_file() 
This function is not yet fully converted to the folio API, but this
removes a few uses of old APIs.

Link: https://lkml.kernel.org/r/20231228085748.1083901-6-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-01-05 10:17:46 -08:00
David Hildenbrand
35668a4321 mm/khugepaged: page_remove_rmap() -> folio_remove_rmap_pte() 
Let's convert __collapse_huge_page_copy_succeeded() and
collapse_pte_mapped_thp().  While at it, perform some more folio
conversion in __collapse_huge_page_copy_succeeded().

We can get rid of release_pte_page().

Link: https://lkml.kernel.org/r/20231220224504.646757-27-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yin Fengwei <fengwei.yin@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2023-12-29 11:58:53 -08:00
Kevin Hao
b39ca20840 mm/khugepaged: remove redundant try_to_freeze() 
A freezable kernel thread can enter frozen state during freezing by either
calling try_to_freeze() or using wait_event_freezable() and its variants. 
However, there is no need to use both methods simultaneously.  The
freezable wait variants have been used in khugepaged_wait_work() and
khugepaged_alloc_sleep(), so remove this redundant try_to_freeze().

I used the following stress-ng command to generate some memory load on my
Intel Alder Lake board (24 CPUs, 32G memory).

	stress-ng --vm 48 --vm-bytes 90%

The worst freezing latency is:
  Freezing user space processes                     
  Freezing user space processes completed (elapsed 0.040 seconds)    
  OOM killer disabled.    
  Freezing remaining freezable tasks    
  Freezing remaining freezable tasks completed (elapsed 0.001 seconds)

Without the faked memory load, the freezing latency is:
  Freezing user space processes
  Freezing user space processes completed (elapsed 0.000 seconds)
  OOM killer disabled.
  Freezing remaining freezable tasks
  Freezing remaining freezable tasks completed (elapsed 0.001 seconds)

I didn't see any observable difference whether this patch is applied or not.

Link: https://lkml.kernel.org/r/20231219231753.683171-1-haokexin@gmail.com
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2023-12-29 11:58:42 -08:00
Matthew Wilcox (Oracle)
5432726848 mm: convert collapse_huge_page() to use a folio 
Replace three calls to compound_head() with one.

Link: https://lkml.kernel.org/r/20231211162214.2146080-9-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2023-12-29 11:58:26 -08:00
Andrea Arcangeli
adef440691 userfaultfd: UFFDIO_MOVE uABI 
Implement the uABI of UFFDIO_MOVE ioctl.
UFFDIO_COPY performs ~20% better than UFFDIO_MOVE when the application
needs pages to be allocated [1]. However, with UFFDIO_MOVE, if pages are
available (in userspace) for recycling, as is usually the case in heap
compaction algorithms, then we can avoid the page allocation and memcpy
(done by UFFDIO_COPY). Also, since the pages are recycled in the
userspace, we avoid the need to release (via madvise) the pages back to
the kernel [2].

We see over 40% reduction (on a Google pixel 6 device) in the compacting
thread's completion time by using UFFDIO_MOVE vs.  UFFDIO_COPY.  This was
measured using a benchmark that emulates a heap compaction implementation
using userfaultfd (to allow concurrent accesses by application threads). 
More details of the usecase are explained in [2].  Furthermore,
UFFDIO_MOVE enables moving swapped-out pages without touching them within
the same vma.  Today, it can only be done by mremap, however it forces
splitting the vma.

[1] https://lore.kernel.org/all/1425575884-2574-1-git-send-email-aarcange@redhat.com/
[2] https://lore.kernel.org/linux-mm/CA+EESO4uO84SSnBhArH4HvLNhaUQ5nZKNKXqxRCyjniNVjp0Aw@mail.gmail.com/

Update for the ioctl_userfaultfd(2)  manpage:

   UFFDIO_MOVE
       (Since Linux xxx)  Move a continuous memory chunk into the
       userfault registered range and optionally wake up the blocked
       thread. The source and destination addresses and the number of
       bytes to move are specified by the src, dst, and len fields of
       the uffdio_move structure pointed to by argp:

           struct uffdio_move {
               __u64 dst;    /* Destination of move */
               __u64 src;    /* Source of move */
               __u64 len;    /* Number of bytes to move */
               __u64 mode;   /* Flags controlling behavior of move */
               __s64 move;   /* Number of bytes moved, or negated error */
           };

       The following value may be bitwise ORed in mode to change the
       behavior of the UFFDIO_MOVE operation:

       UFFDIO_MOVE_MODE_DONTWAKE
              Do not wake up the thread that waits for page-fault
              resolution

       UFFDIO_MOVE_MODE_ALLOW_SRC_HOLES
              Allow holes in the source virtual range that is being moved.
              When not specified, the holes will result in ENOENT error.
              When specified, the holes will be accounted as successfully
              moved memory. This is mostly useful to move hugepage aligned
              virtual regions without knowing if there are transparent
              hugepages in the regions or not, but preventing the risk of
              having to split the hugepage during the operation.

       The move field is used by the kernel to return the number of
       bytes that was actually moved, or an error (a negated errno-
       style value).  If the value returned in move doesn't match the
       value that was specified in len, the operation fails with the
       error EAGAIN.  The move field is output-only; it is not read by
       the UFFDIO_MOVE operation.

       The operation may fail for various reasons. Usually, remapping of
       pages that are not exclusive to the given process fail; once KSM
       might deduplicate pages or fork() COW-shares pages during fork()
       with child processes, they are no longer exclusive. Further, the
       kernel might only perform lightweight checks for detecting whether
       the pages are exclusive, and return -EBUSY in case that check fails.
       To make the operation more likely to succeed, KSM should be
       disabled, fork() should be avoided or MADV_DONTFORK should be
       configured for the source VMA before fork().

       This ioctl(2) operation returns 0 on success.  In this case, the
       entire area was moved.  On error, -1 is returned and errno is
       set to indicate the error.  Possible errors include:

       EAGAIN The number of bytes moved (i.e., the value returned in
              the move field) does not equal the value that was
              specified in the len field.

       EINVAL Either dst or len was not a multiple of the system page
              size, or the range specified by src and len or dst and len
              was invalid.

       EINVAL An invalid bit was specified in the mode field.

       ENOENT
              The source virtual memory range has unmapped holes and
              UFFDIO_MOVE_MODE_ALLOW_SRC_HOLES is not set.

       EEXIST
              The destination virtual memory range is fully or partially
              mapped.

       EBUSY
              The pages in the source virtual memory range are either
              pinned or not exclusive to the process. The kernel might
              only perform lightweight checks for detecting whether the
              pages are exclusive. To make the operation more likely to
              succeed, KSM should be disabled, fork() should be avoided
              or MADV_DONTFORK should be configured for the source virtual
              memory area before fork().

       ENOMEM Allocating memory needed for the operation failed.

       ESRCH
              The target process has exited at the time of a UFFDIO_MOVE
              operation.

Link: https://lkml.kernel.org/r/20231206103702.3873743-3-surenb@google.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Nicolas Geoffray <ngeoffray@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: ZhangPeng <zhangpeng362@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2023-12-29 11:58:24 -08:00
Kent Overstreet
1e2f2d3199 Kill sched.h dependency on rcupdate.h 
by moving cond_resched_rcu() to rcupdate_wait.h, we can kill another big
sched.h dependency.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
 2023-12-27 11:50:20 -05:00
Ryan Roberts
3485b88390 mm: thp: introduce multi-size THP sysfs interface 
In preparation for adding support for anonymous multi-size THP, introduce
new sysfs structure that will be used to control the new behaviours.  A
new directory is added under transparent_hugepage for each supported THP
size, and contains an `enabled` file, which can be set to "inherit" (to
inherit the global setting), "always", "madvise" or "never".  For now, the
kernel still only supports PMD-sized anonymous THP, so only 1 directory is
populated.

The first half of the change converts transhuge_vma_suitable() and
hugepage_vma_check() so that they take a bitfield of orders for which the
user wants to determine support, and the functions filter out all the
orders that can't be supported, given the current sysfs configuration and
the VMA dimensions.  The resulting functions are renamed to
thp_vma_suitable_orders() and thp_vma_allowable_orders() respectively. 
Convenience functions that take a single, unencoded order and return a
boolean are also defined as thp_vma_suitable_order() and
thp_vma_allowable_order().

The second half of the change implements the new sysfs interface.  It has
been done so that each supported THP size has a `struct thpsize`, which
describes the relevant metadata and is itself a kobject.  This is pretty
minimal for now, but should make it easy to add new per-thpsize files to
the interface if needed in future (e.g.  per-size defrag).  Rather than
keep the `enabled` state directly in the struct thpsize, I've elected to
directly encode it into huge_anon_orders_[always|madvise|inherit]
bitfields since this reduces the amount of work required in
thp_vma_allowable_orders() which is called for every page fault.

See Documentation/admin-guide/mm/transhuge.rst, as modified by this
commit, for details of how the new sysfs interface works.

[ryan.roberts@arm.com: fix build warning when CONFIG_SYSFS is disabled]
  Link: https://lkml.kernel.org/r/20231211125320.3997543-1-ryan.roberts@arm.com
Link: https://lkml.kernel.org/r/20231207161211.2374093-4-ryan.roberts@arm.com
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Barry Song <v-songbaohua@oppo.com>
Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Tested-by: John Hubbard <jhubbard@nvidia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Itaru Kitayama <itaru.kitayama@gmail.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yin Fengwei <fengwei.yin@intel.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2023-12-20 14:48:12 -08:00
Linus Torvalds
8f6f76a6a2 As usual, lots of singleton and doubleton patches all over the tree and 
there's little I can say which isn't in the individual changelogs.
 
 The lengthier patch series are
 
 - "kdump: use generic functions to simplify crashkernel reservation in
   arch", from Baoquan He.  This is mainly cleanups and consolidation of
   the "crashkernel=" kernel parameter handling.
 
 - After much discussion, David Laight's "minmax: Relax type checks in
   min() and max()" is here.  Hopefully reduces some typecasting and the
   use of min_t() and max_t().
 
 - A group of patches from Oleg Nesterov which clean up and slightly fix
   our handling of reads from /proc/PID/task/...  and which remove
   task_struct.therad_group.
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Merge tag 'mm-nonmm-stable-2023-11-02-14-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:
 "As usual, lots of singleton and doubleton patches all over the tree
  and there's little I can say which isn't in the individual changelogs.

  The lengthier patch series are

   - 'kdump: use generic functions to simplify crashkernel reservation
     in arch', from Baoquan He. This is mainly cleanups and
     consolidation of the 'crashkernel=' kernel parameter handling

   - After much discussion, David Laight's 'minmax: Relax type checks in
     min() and max()' is here. Hopefully reduces some typecasting and
     the use of min_t() and max_t()

   - A group of patches from Oleg Nesterov which clean up and slightly
     fix our handling of reads from /proc/PID/task/... and which remove
     task_struct.thread_group"

* tag 'mm-nonmm-stable-2023-11-02-14-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (64 commits)
  scripts/gdb/vmalloc: disable on no-MMU
  scripts/gdb: fix usage of MOD_TEXT not defined when CONFIG_MODULES=n
  .mailmap: add address mapping for Tomeu Vizoso
  mailmap: update email address for Claudiu Beznea
  tools/testing/selftests/mm/run_vmtests.sh: lower the ptrace permissions
  .mailmap: map Benjamin Poirier's address
  scripts/gdb: add lx_current support for riscv
  ocfs2: fix a spelling typo in comment
  proc: test ProtectionKey in proc-empty-vm test
  proc: fix proc-empty-vm test with vsyscall
  fs/proc/base.c: remove unneeded semicolon
  do_io_accounting: use sig->stats_lock
  do_io_accounting: use __for_each_thread()
  ocfs2: replace BUG_ON() at ocfs2_num_free_extents() with ocfs2_error()
  ocfs2: fix a typo in a comment
  scripts/show_delta: add __main__ judgement before main code
  treewide: mark stuff as __ro_after_init
  fs: ocfs2: check status values
  proc: test /proc/${pid}/statm
  compiler.h: move __is_constexpr() to compiler.h
  ...
 2023-11-02 20:53:31 -10:00
Vishal Moola (Oracle)
98b32d296d mm/khugepaged: convert collapse_pte_mapped_thp() to use folios 
This removes 2 calls to compound_head() and helps convert khugepaged to
use folios throughout.

Previously, if the address passed to collapse_pte_mapped_thp()
corresponded to a tail page, the scan would fail immediately. Using
filemap_lock_folio() we get the corresponding folio back and try to
operate on the folio instead.

Link: https://lkml.kernel.org/r/20231020183331.10770-6-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2023-10-25 16:47:14 -07:00
Vishal Moola (Oracle)
b455f39d22 mm/khugepaged: convert alloc_charge_hpage() to use folios 
Also remove count_memcg_page_event now that its last caller no longer uses
it and reword hpage_collapse_alloc_page() to hpage_collapse_alloc_folio().

This removes 1 call to compound_head() and helps convert khugepaged to
use folios throughout.

Link: https://lkml.kernel.org/r/20231020183331.10770-5-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2023-10-25 16:47:14 -07:00
Vishal Moola (Oracle)
dbf85c21e4 mm/khugepaged: convert is_refcount_suitable() to use folios 
Both callers of is_refcount_suitable() have been converted to use
folios, so convert it to take in a folio. Both callers only operate on
head pages of folios so mapcount/refcount conversions here are trivial.

Removes 3 calls to compound head, and removes 315 bytes of kernel text.

Link: https://lkml.kernel.org/r/20231020183331.10770-4-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2023-10-25 16:47:14 -07:00
Vishal Moola (Oracle)
5c07ebb372 mm/khugepaged: convert hpage_collapse_scan_pmd() to use folios 
Replaces 5 calls to compound_head(), and removes 1385 bytes of kernel
text.

Link: https://lkml.kernel.org/r/20231020183331.10770-3-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2023-10-25 16:47:14 -07:00
Vishal Moola (Oracle)
8dd1e89673 mm/khugepaged: convert __collapse_huge_page_isolate() to use folios 
Patch series "Some khugepaged folio conversions", v3.

This patchset converts a number of functions to use folios.  This cleans
up some khugepaged code and removes a large number of hidden
compound_head() calls.


This patch (of 5):

Replaces 11 calls to compound_head() with 1, and removes 1348 bytes of
kernel text.

Link: https://lkml.kernel.org/r/20231020183331.10770-1-vishal.moola@gmail.com
Link: https://lkml.kernel.org/r/20231020183331.10770-2-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2023-10-25 16:47:14 -07:00
Alexey Dobriyan
68279f9c9f treewide: mark stuff as __ro_after_init 
__read_mostly predates __ro_after_init. Many variables which are marked
__read_mostly should have been __ro_after_init from day 1.

Also, mark some stuff as "const" and "__init" while I'm at it.

[akpm@linux-foundation.org: revert sysctl_nr_open_min, sysctl_nr_open_max changes due to arm warning]
[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/4f6bb9c0-abba-4ee4-a7aa-89265e886817@p183
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2023-10-18 14:43:23 -07:00
Linus Torvalds
b96a3e9142 - Some swap cleanups from Ma Wupeng ("fix WARN_ON in add_to_avail_list") 
- Peter Xu has a series (mm/gup: Unify hugetlb, speed up thp") which
   reduces the special-case code for handling hugetlb pages in GUP.  It
   also speeds up GUP handling of transparent hugepages.
 
 - Peng Zhang provides some maple tree speedups ("Optimize the fast path
   of mas_store()").
 
 - Sergey Senozhatsky has improved te performance of zsmalloc during
   compaction (zsmalloc: small compaction improvements").
 
 - Domenico Cerasuolo has developed additional selftest code for zswap
   ("selftests: cgroup: add zswap test program").
 
 - xu xin has doe some work on KSM's handling of zero pages.  These
   changes are mainly to enable the user to better understand the
   effectiveness of KSM's treatment of zero pages ("ksm: support tracking
   KSM-placed zero-pages").
 
 - Jeff Xu has fixes the behaviour of memfd's
   MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED sysctl ("mm/memfd: fix sysctl
   MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED").
 
 - David Howells has fixed an fscache optimization ("mm, netfs, fscache:
   Stop read optimisation when folio removed from pagecache").
 
 - Axel Rasmussen has given userfaultfd the ability to simulate memory
   poisoning ("add UFFDIO_POISON to simulate memory poisoning with UFFD").
 
 - Miaohe Lin has contributed some routine maintenance work on the
   memory-failure code ("mm: memory-failure: remove unneeded PageHuge()
   check").
 
 - Peng Zhang has contributed some maintenance work on the maple tree
   code ("Improve the validation for maple tree and some cleanup").
 
 - Hugh Dickins has optimized the collapsing of shmem or file pages into
   THPs ("mm: free retracted page table by RCU").
 
 - Jiaqi Yan has a patch series which permits us to use the healthy
   subpages within a hardware poisoned huge page for general purposes
   ("Improve hugetlbfs read on HWPOISON hugepages").
 
 - Kemeng Shi has done some maintenance work on the pagetable-check code
   ("Remove unused parameters in page_table_check").
 
 - More folioification work from Matthew Wilcox ("More filesystem folio
   conversions for 6.6"), ("Followup folio conversions for zswap").  And
   from ZhangPeng ("Convert several functions in page_io.c to use a
   folio").
 
 - page_ext cleanups from Kemeng Shi ("minor cleanups for page_ext").
 
 - Baoquan He has converted some architectures to use the GENERIC_IOREMAP
   ioremap()/iounmap() code ("mm: ioremap: Convert architectures to take
   GENERIC_IOREMAP way").
 
 - Anshuman Khandual has optimized arm64 tlb shootdown ("arm64: support
   batched/deferred tlb shootdown during page reclamation/migration").
 
 - Better maple tree lockdep checking from Liam Howlett ("More strict
   maple tree lockdep").  Liam also developed some efficiency improvements
   ("Reduce preallocations for maple tree").
 
 - Cleanup and optimization to the secondary IOMMU TLB invalidation, from
   Alistair Popple ("Invalidate secondary IOMMU TLB on permission
   upgrade").
 
 - Ryan Roberts fixes some arm64 MM selftest issues ("selftests/mm fixes
   for arm64").
 
 - Kemeng Shi provides some maintenance work on the compaction code ("Two
   minor cleanups for compaction").
 
 - Some reduction in mmap_lock pressure from Matthew Wilcox ("Handle most
   file-backed faults under the VMA lock").
 
 - Aneesh Kumar contributes code to use the vmemmap optimization for DAX
   on ppc64, under some circumstances ("Add support for DAX vmemmap
   optimization for ppc64").
 
 - page-ext cleanups from Kemeng Shi ("add page_ext_data to get client
   data in page_ext"), ("minor cleanups to page_ext header").
 
 - Some zswap cleanups from Johannes Weiner ("mm: zswap: three
   cleanups").
 
 - kmsan cleanups from ZhangPeng ("minor cleanups for kmsan").
 
 - VMA handling cleanups from Kefeng Wang ("mm: convert to
   vma_is_initial_heap/stack()").
 
 - DAMON feature work from SeongJae Park ("mm/damon/sysfs-schemes:
   implement DAMOS tried total bytes file"), ("Extend DAMOS filters for
   address ranges and DAMON monitoring targets").
 
 - Compaction work from Kemeng Shi ("Fixes and cleanups to compaction").
 
 - Liam Howlett has improved the maple tree node replacement code
   ("maple_tree: Change replacement strategy").
 
 - ZhangPeng has a general code cleanup - use the K() macro more widely
   ("cleanup with helper macro K()").
 
 - Aneesh Kumar brings memmap-on-memory to ppc64 ("Add support for memmap
   on memory feature on ppc64").
 
 - pagealloc cleanups from Kemeng Shi ("Two minor cleanups for pcp list
   in page_alloc"), ("Two minor cleanups for get pageblock migratetype").
 
 - Vishal Moola introduces a memory descriptor for page table tracking,
   "struct ptdesc" ("Split ptdesc from struct page").
 
 - memfd selftest maintenance work from Aleksa Sarai ("memfd: cleanups
   for vm.memfd_noexec").
 
 - MM include file rationalization from Hugh Dickins ("arch: include
   asm/cacheflush.h in asm/hugetlb.h").
 
 - THP debug output fixes from Hugh Dickins ("mm,thp: fix sloppy text
   output").
 
 - kmemleak improvements from Xiaolei Wang ("mm/kmemleak: use
   object_cache instead of kmemleak_initialized").
 
 - More folio-related cleanups from Matthew Wilcox ("Remove _folio_dtor
   and _folio_order").
 
 - A VMA locking scalability improvement from Suren Baghdasaryan
   ("Per-VMA lock support for swap and userfaults").
 
 - pagetable handling cleanups from Matthew Wilcox ("New page table range
   API").
 
 - A batch of swap/thp cleanups from David Hildenbrand ("mm/swap: stop
   using page->private on tail pages for THP_SWAP + cleanups").
 
 - Cleanups and speedups to the hugetlb fault handling from Matthew
   Wilcox ("Change calling convention for ->huge_fault").
 
 - Matthew Wilcox has also done some maintenance work on the MM subsystem
   documentation ("Improve mm documentation").
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Merge tag 'mm-stable-2023-08-28-18-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - Some swap cleanups from Ma Wupeng ("fix WARN_ON in
   add_to_avail_list")

 - Peter Xu has a series (mm/gup: Unify hugetlb, speed up thp") which
   reduces the special-case code for handling hugetlb pages in GUP. It
   also speeds up GUP handling of transparent hugepages.

 - Peng Zhang provides some maple tree speedups ("Optimize the fast path
   of mas_store()").

 - Sergey Senozhatsky has improved te performance of zsmalloc during
   compaction (zsmalloc: small compaction improvements").

 - Domenico Cerasuolo has developed additional selftest code for zswap
   ("selftests: cgroup: add zswap test program").

 - xu xin has doe some work on KSM's handling of zero pages. These
   changes are mainly to enable the user to better understand the
   effectiveness of KSM's treatment of zero pages ("ksm: support
   tracking KSM-placed zero-pages").

 - Jeff Xu has fixes the behaviour of memfd's
   MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED sysctl ("mm/memfd: fix sysctl
   MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED").

 - David Howells has fixed an fscache optimization ("mm, netfs, fscache:
   Stop read optimisation when folio removed from pagecache").

 - Axel Rasmussen has given userfaultfd the ability to simulate memory
   poisoning ("add UFFDIO_POISON to simulate memory poisoning with
   UFFD").

 - Miaohe Lin has contributed some routine maintenance work on the
   memory-failure code ("mm: memory-failure: remove unneeded PageHuge()
   check").

 - Peng Zhang has contributed some maintenance work on the maple tree
   code ("Improve the validation for maple tree and some cleanup").

 - Hugh Dickins has optimized the collapsing of shmem or file pages into
   THPs ("mm: free retracted page table by RCU").

 - Jiaqi Yan has a patch series which permits us to use the healthy
   subpages within a hardware poisoned huge page for general purposes
   ("Improve hugetlbfs read on HWPOISON hugepages").

 - Kemeng Shi has done some maintenance work on the pagetable-check code
   ("Remove unused parameters in page_table_check").

 - More folioification work from Matthew Wilcox ("More filesystem folio
   conversions for 6.6"), ("Followup folio conversions for zswap"). And
   from ZhangPeng ("Convert several functions in page_io.c to use a
   folio").

 - page_ext cleanups from Kemeng Shi ("minor cleanups for page_ext").

 - Baoquan He has converted some architectures to use the
   GENERIC_IOREMAP ioremap()/iounmap() code ("mm: ioremap: Convert
   architectures to take GENERIC_IOREMAP way").

 - Anshuman Khandual has optimized arm64 tlb shootdown ("arm64: support
   batched/deferred tlb shootdown during page reclamation/migration").

 - Better maple tree lockdep checking from Liam Howlett ("More strict
   maple tree lockdep"). Liam also developed some efficiency
   improvements ("Reduce preallocations for maple tree").

 - Cleanup and optimization to the secondary IOMMU TLB invalidation,
   from Alistair Popple ("Invalidate secondary IOMMU TLB on permission
   upgrade").

 - Ryan Roberts fixes some arm64 MM selftest issues ("selftests/mm fixes
   for arm64").

 - Kemeng Shi provides some maintenance work on the compaction code
   ("Two minor cleanups for compaction").

 - Some reduction in mmap_lock pressure from Matthew Wilcox ("Handle
   most file-backed faults under the VMA lock").

 - Aneesh Kumar contributes code to use the vmemmap optimization for DAX
   on ppc64, under some circumstances ("Add support for DAX vmemmap
   optimization for ppc64").

 - page-ext cleanups from Kemeng Shi ("add page_ext_data to get client
   data in page_ext"), ("minor cleanups to page_ext header").

 - Some zswap cleanups from Johannes Weiner ("mm: zswap: three
   cleanups").

 - kmsan cleanups from ZhangPeng ("minor cleanups for kmsan").

 - VMA handling cleanups from Kefeng Wang ("mm: convert to
   vma_is_initial_heap/stack()").

 - DAMON feature work from SeongJae Park ("mm/damon/sysfs-schemes:
   implement DAMOS tried total bytes file"), ("Extend DAMOS filters for
   address ranges and DAMON monitoring targets").

 - Compaction work from Kemeng Shi ("Fixes and cleanups to compaction").

 - Liam Howlett has improved the maple tree node replacement code
   ("maple_tree: Change replacement strategy").

 - ZhangPeng has a general code cleanup - use the K() macro more widely
   ("cleanup with helper macro K()").

 - Aneesh Kumar brings memmap-on-memory to ppc64 ("Add support for
   memmap on memory feature on ppc64").

 - pagealloc cleanups from Kemeng Shi ("Two minor cleanups for pcp list
   in page_alloc"), ("Two minor cleanups for get pageblock
   migratetype").

 - Vishal Moola introduces a memory descriptor for page table tracking,
   "struct ptdesc" ("Split ptdesc from struct page").

 - memfd selftest maintenance work from Aleksa Sarai ("memfd: cleanups
   for vm.memfd_noexec").

 - MM include file rationalization from Hugh Dickins ("arch: include
   asm/cacheflush.h in asm/hugetlb.h").

 - THP debug output fixes from Hugh Dickins ("mm,thp: fix sloppy text
   output").

 - kmemleak improvements from Xiaolei Wang ("mm/kmemleak: use
   object_cache instead of kmemleak_initialized").

 - More folio-related cleanups from Matthew Wilcox ("Remove _folio_dtor
   and _folio_order").

 - A VMA locking scalability improvement from Suren Baghdasaryan
   ("Per-VMA lock support for swap and userfaults").

 - pagetable handling cleanups from Matthew Wilcox ("New page table
   range API").

 - A batch of swap/thp cleanups from David Hildenbrand ("mm/swap: stop
   using page->private on tail pages for THP_SWAP + cleanups").

 - Cleanups and speedups to the hugetlb fault handling from Matthew
   Wilcox ("Change calling convention for ->huge_fault").

 - Matthew Wilcox has also done some maintenance work on the MM
   subsystem documentation ("Improve mm documentation").

* tag 'mm-stable-2023-08-28-18-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (489 commits)
  maple_tree: shrink struct maple_tree
  maple_tree: clean up mas_wr_append()
  secretmem: convert page_is_secretmem() to folio_is_secretmem()
  nios2: fix flush_dcache_page() for usage from irq context
  hugetlb: add documentation for vma_kernel_pagesize()
  mm: add orphaned kernel-doc to the rst files.
  mm: fix clean_record_shared_mapping_range kernel-doc
  mm: fix get_mctgt_type() kernel-doc
  mm: fix kernel-doc warning from tlb_flush_rmaps()
  mm: remove enum page_entry_size
  mm: allow ->huge_fault() to be called without the mmap_lock held
  mm: move PMD_ORDER to pgtable.h
  mm: remove checks for pte_index
  memcg: remove duplication detection for mem_cgroup_uncharge_swap
  mm/huge_memory: work on folio->swap instead of page->private when splitting folio
  mm/swap: inline folio_set_swap_entry() and folio_swap_entry()
  mm/swap: use dedicated entry for swap in folio
  mm/swap: stop using page->private on tail pages for THP_SWAP
  selftests/mm: fix WARNING comparing pointer to 0
  selftests: cgroup: fix test_kmem_memcg_deletion kernel mem check
  ...
 2023-08-29 14:25:26 -07:00