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author | Linus Torvalds <torvalds@linux-foundation.org> | 2023-11-02 19:38:47 -1000 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2023-11-02 19:38:47 -1000 |
commit | ecae0bd5173b1014f95a14a8dfbe40ec10367dcf (patch) | |
tree | f571213ef1a35354ea79f0240a180fdb4111b290 /mm/rmap.c | |
parent | bc3012f4e3a9765de81f454cb8f9bb16aafc6ff5 (diff) | |
parent | 9732336006764e2ee61225387e3c70eae9139035 (diff) | |
download | lwn-ecae0bd5173b1014f95a14a8dfbe40ec10367dcf.tar.gz lwn-ecae0bd5173b1014f95a14a8dfbe40ec10367dcf.zip |
Merge tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
"Many singleton patches against the MM code. The patch series which are
included in this merge do the following:
- Kemeng Shi has contributed some compation maintenance work in the
series 'Fixes and cleanups to compaction'
- Joel Fernandes has a patchset ('Optimize mremap during mutual
alignment within PMD') which fixes an obscure issue with mremap()'s
pagetable handling during a subsequent exec(), based upon an
implementation which Linus suggested
- More DAMON/DAMOS maintenance and feature work from SeongJae Park i
the following patch series:
mm/damon: misc fixups for documents, comments and its tracepoint
mm/damon: add a tracepoint for damos apply target regions
mm/damon: provide pseudo-moving sum based access rate
mm/damon: implement DAMOS apply intervals
mm/damon/core-test: Fix memory leaks in core-test
mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval
- In the series 'Do not try to access unaccepted memory' Adrian
Hunter provides some fixups for the recently-added 'unaccepted
memory' feature. To increase the feature's checking coverage. 'Plug
a few gaps where RAM is exposed without checking if it is
unaccepted memory'
- In the series 'cleanups for lockless slab shrink' Qi Zheng has done
some maintenance work which is preparation for the lockless slab
shrinking code
- Qi Zheng has redone the earlier (and reverted) attempt to make slab
shrinking lockless in the series 'use refcount+RCU method to
implement lockless slab shrink'
- David Hildenbrand contributes some maintenance work for the rmap
code in the series 'Anon rmap cleanups'
- Kefeng Wang does more folio conversions and some maintenance work
in the migration code. Series 'mm: migrate: more folio conversion
and unification'
- Matthew Wilcox has fixed an issue in the buffer_head code which was
causing long stalls under some heavy memory/IO loads. Some cleanups
were added on the way. Series 'Add and use bdev_getblk()'
- In the series 'Use nth_page() in place of direct struct page
manipulation' Zi Yan has fixed a potential issue with the direct
manipulation of hugetlb page frames
- In the series 'mm: hugetlb: Skip initialization of gigantic tail
struct pages if freed by HVO' has improved our handling of gigantic
pages in the hugetlb vmmemmep optimizaton code. This provides
significant boot time improvements when significant amounts of
gigantic pages are in use
- Matthew Wilcox has sent the series 'Small hugetlb cleanups' - code
rationalization and folio conversions in the hugetlb code
- Yin Fengwei has improved mlock()'s handling of large folios in the
series 'support large folio for mlock'
- In the series 'Expose swapcache stat for memcg v1' Liu Shixin has
added statistics for memcg v1 users which are available (and
useful) under memcg v2
- Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable)
prctl so that userspace may direct the kernel to not automatically
propagate the denial to child processes. The series is named 'MDWE
without inheritance'
- Kefeng Wang has provided the series 'mm: convert numa balancing
functions to use a folio' which does what it says
- In the series 'mm/ksm: add fork-exec support for prctl' Stefan
Roesch makes is possible for a process to propagate KSM treatment
across exec()
- Huang Ying has enhanced memory tiering's calculation of memory
distances. This is used to permit the dax/kmem driver to use 'high
bandwidth memory' in addition to Optane Data Center Persistent
Memory Modules (DCPMM). The series is named 'memory tiering:
calculate abstract distance based on ACPI HMAT'
- In the series 'Smart scanning mode for KSM' Stefan Roesch has
optimized KSM by teaching it to retain and use some historical
information from previous scans
- Yosry Ahmed has fixed some inconsistencies in memcg statistics in
the series 'mm: memcg: fix tracking of pending stats updates
values'
- In the series 'Implement IOCTL to get and optionally clear info
about PTEs' Peter Xu has added an ioctl to /proc/<pid>/pagemap
which permits us to atomically read-then-clear page softdirty
state. This is mainly used by CRIU
- Hugh Dickins contributed the series 'shmem,tmpfs: general
maintenance', a bunch of relatively minor maintenance tweaks to
this code
- Matthew Wilcox has increased the use of the VMA lock over
file-backed page faults in the series 'Handle more faults under the
VMA lock'. Some rationalizations of the fault path became possible
as a result
- In the series 'mm/rmap: convert page_move_anon_rmap() to
folio_move_anon_rmap()' David Hildenbrand has implemented some
cleanups and folio conversions
- In the series 'various improvements to the GUP interface' Lorenzo
Stoakes has simplified and improved the GUP interface with an eye
to providing groundwork for future improvements
- Andrey Konovalov has sent along the series 'kasan: assorted fixes
and improvements' which does those things
- Some page allocator maintenance work from Kemeng Shi in the series
'Two minor cleanups to break_down_buddy_pages'
- In thes series 'New selftest for mm' Breno Leitao has developed
another MM self test which tickles a race we had between madvise()
and page faults
- In the series 'Add folio_end_read' Matthew Wilcox provides cleanups
and an optimization to the core pagecache code
- Nhat Pham has added memcg accounting for hugetlb memory in the
series 'hugetlb memcg accounting'
- Cleanups and rationalizations to the pagemap code from Lorenzo
Stoakes, in the series 'Abstract vma_merge() and split_vma()'
- Audra Mitchell has fixed issues in the procfs page_owner code's new
timestamping feature which was causing some misbehaviours. In the
series 'Fix page_owner's use of free timestamps'
- Lorenzo Stoakes has fixed the handling of new mappings of sealed
files in the series 'permit write-sealed memfd read-only shared
mappings'
- Mike Kravetz has optimized the hugetlb vmemmap optimization in the
series 'Batch hugetlb vmemmap modification operations'
- Some buffer_head folio conversions and cleanups from Matthew Wilcox
in the series 'Finish the create_empty_buffers() transition'
- As a page allocator performance optimization Huang Ying has added
automatic tuning to the allocator's per-cpu-pages feature, in the
series 'mm: PCP high auto-tuning'
- Roman Gushchin has contributed the patchset 'mm: improve
performance of accounted kernel memory allocations' which improves
their performance by ~30% as measured by a micro-benchmark
- folio conversions from Kefeng Wang in the series 'mm: convert page
cpupid functions to folios'
- Some kmemleak fixups in Liu Shixin's series 'Some bugfix about
kmemleak'
- Qi Zheng has improved our handling of memoryless nodes by keeping
them off the allocation fallback list. This is done in the series
'handle memoryless nodes more appropriately'
- khugepaged conversions from Vishal Moola in the series 'Some
khugepaged folio conversions'"
[ bcachefs conflicts with the dynamically allocated shrinkers have been
resolved as per Stephen Rothwell in
https://lore.kernel.org/all/20230913093553.4290421e@canb.auug.org.au/
with help from Qi Zheng.
The clone3 test filtering conflict was half-arsed by yours truly ]
* tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (406 commits)
mm/damon/sysfs: update monitoring target regions for online input commit
mm/damon/sysfs: remove requested targets when online-commit inputs
selftests: add a sanity check for zswap
Documentation: maple_tree: fix word spelling error
mm/vmalloc: fix the unchecked dereference warning in vread_iter()
zswap: export compression failure stats
Documentation: ubsan: drop "the" from article title
mempolicy: migration attempt to match interleave nodes
mempolicy: mmap_lock is not needed while migrating folios
mempolicy: alloc_pages_mpol() for NUMA policy without vma
mm: add page_rmappable_folio() wrapper
mempolicy: remove confusing MPOL_MF_LAZY dead code
mempolicy: mpol_shared_policy_init() without pseudo-vma
mempolicy trivia: use pgoff_t in shared mempolicy tree
mempolicy trivia: slightly more consistent naming
mempolicy trivia: delete those ancient pr_debug()s
mempolicy: fix migrate_pages(2) syscall return nr_failed
kernfs: drop shared NUMA mempolicy hooks
hugetlbfs: drop shared NUMA mempolicy pretence
mm/damon/sysfs-test: add a unit test for damon_sysfs_set_targets()
...
Diffstat (limited to 'mm/rmap.c')
-rw-r--r-- | mm/rmap.c | 164 |
1 files changed, 101 insertions, 63 deletions
diff --git a/mm/rmap.c b/mm/rmap.c index 9f795b93cf40..7a27a2b41802 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -798,6 +798,7 @@ struct folio_referenced_arg { unsigned long vm_flags; struct mem_cgroup *memcg; }; + /* * arg: folio_referenced_arg will be passed */ @@ -807,17 +808,33 @@ static bool folio_referenced_one(struct folio *folio, struct folio_referenced_arg *pra = arg; DEFINE_FOLIO_VMA_WALK(pvmw, folio, vma, address, 0); int referenced = 0; + unsigned long start = address, ptes = 0; while (page_vma_mapped_walk(&pvmw)) { address = pvmw.address; - if ((vma->vm_flags & VM_LOCKED) && - (!folio_test_large(folio) || !pvmw.pte)) { - /* Restore the mlock which got missed */ - mlock_vma_folio(folio, vma, !pvmw.pte); - page_vma_mapped_walk_done(&pvmw); - pra->vm_flags |= VM_LOCKED; - return false; /* To break the loop */ + if (vma->vm_flags & VM_LOCKED) { + if (!folio_test_large(folio) || !pvmw.pte) { + /* Restore the mlock which got missed */ + mlock_vma_folio(folio, vma); + page_vma_mapped_walk_done(&pvmw); + pra->vm_flags |= VM_LOCKED; + return false; /* To break the loop */ + } + /* + * For large folio fully mapped to VMA, will + * be handled after the pvmw loop. + * + * For large folio cross VMA boundaries, it's + * expected to be picked by page reclaim. But + * should skip reference of pages which are in + * the range of VM_LOCKED vma. As page reclaim + * should just count the reference of pages out + * the range of VM_LOCKED vma. + */ + ptes++; + pra->mapcount--; + continue; } if (pvmw.pte) { @@ -842,6 +859,23 @@ static bool folio_referenced_one(struct folio *folio, pra->mapcount--; } + if ((vma->vm_flags & VM_LOCKED) && + folio_test_large(folio) && + folio_within_vma(folio, vma)) { + unsigned long s_align, e_align; + + s_align = ALIGN_DOWN(start, PMD_SIZE); + e_align = ALIGN_DOWN(start + folio_size(folio) - 1, PMD_SIZE); + + /* folio doesn't cross page table boundary and fully mapped */ + if ((s_align == e_align) && (ptes == folio_nr_pages(folio))) { + /* Restore the mlock which got missed */ + mlock_vma_folio(folio, vma); + pra->vm_flags |= VM_LOCKED; + return false; /* To break the loop */ + } + } + if (referenced) folio_clear_idle(folio); if (folio_test_clear_young(folio)) @@ -1094,19 +1128,17 @@ int folio_total_mapcount(struct folio *folio) } /** - * page_move_anon_rmap - move a page to our anon_vma - * @page: the page to move to our anon_vma - * @vma: the vma the page belongs to + * folio_move_anon_rmap - move a folio to our anon_vma + * @folio: The folio to move to our anon_vma + * @vma: The vma the folio belongs to * - * When a page belongs exclusively to one process after a COW event, - * that page can be moved into the anon_vma that belongs to just that - * process, so the rmap code will not search the parent or sibling - * processes. + * When a folio belongs exclusively to one process after a COW event, + * that folio can be moved into the anon_vma that belongs to just that + * process, so the rmap code will not search the parent or sibling processes. */ -void page_move_anon_rmap(struct page *page, struct vm_area_struct *vma) +void folio_move_anon_rmap(struct folio *folio, struct vm_area_struct *vma) { void *anon_vma = vma->anon_vma; - struct folio *folio = page_folio(page); VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); VM_BUG_ON_VMA(!anon_vma, vma); @@ -1118,31 +1150,25 @@ void page_move_anon_rmap(struct page *page, struct vm_area_struct *vma) * folio_test_anon()) will not see one without the other. */ WRITE_ONCE(folio->mapping, anon_vma); - SetPageAnonExclusive(page); } /** - * __page_set_anon_rmap - set up new anonymous rmap - * @folio: Folio which contains page. - * @page: Page to add to rmap. - * @vma: VM area to add page to. + * __folio_set_anon - set up a new anonymous rmap for a folio + * @folio: The folio to set up the new anonymous rmap for. + * @vma: VM area to add the folio to. * @address: User virtual address of the mapping - * @exclusive: the page is exclusively owned by the current process + * @exclusive: Whether the folio is exclusive to the process. */ -static void __page_set_anon_rmap(struct folio *folio, struct page *page, - struct vm_area_struct *vma, unsigned long address, int exclusive) +static void __folio_set_anon(struct folio *folio, struct vm_area_struct *vma, + unsigned long address, bool exclusive) { struct anon_vma *anon_vma = vma->anon_vma; BUG_ON(!anon_vma); - if (folio_test_anon(folio)) - goto out; - /* - * If the page isn't exclusively mapped into this vma, - * we must use the _oldest_ possible anon_vma for the - * page mapping! + * If the folio isn't exclusive to this vma, we must use the _oldest_ + * possible anon_vma for the folio mapping! */ if (!exclusive) anon_vma = anon_vma->root; @@ -1156,9 +1182,6 @@ static void __page_set_anon_rmap(struct folio *folio, struct page *page, anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON; WRITE_ONCE(folio->mapping, (struct address_space *) anon_vma); folio->index = linear_page_index(vma, address); -out: - if (exclusive) - SetPageAnonExclusive(page); } /** @@ -1207,7 +1230,7 @@ void page_add_anon_rmap(struct page *page, struct vm_area_struct *vma, atomic_t *mapped = &folio->_nr_pages_mapped; int nr = 0, nr_pmdmapped = 0; bool compound = flags & RMAP_COMPOUND; - bool first = true; + bool first; /* Is page being mapped by PTE? Is this its first map to be added? */ if (likely(!compound)) { @@ -1236,24 +1259,40 @@ void page_add_anon_rmap(struct page *page, struct vm_area_struct *vma, } } - VM_BUG_ON_PAGE(!first && (flags & RMAP_EXCLUSIVE), page); - VM_BUG_ON_PAGE(!first && PageAnonExclusive(page), page); - if (nr_pmdmapped) __lruvec_stat_mod_folio(folio, NR_ANON_THPS, nr_pmdmapped); if (nr) __lruvec_stat_mod_folio(folio, NR_ANON_MAPPED, nr); - if (likely(!folio_test_ksm(folio))) { - /* address might be in next vma when migration races vma_merge */ - if (first) - __page_set_anon_rmap(folio, page, vma, address, - !!(flags & RMAP_EXCLUSIVE)); - else - __page_check_anon_rmap(folio, page, vma, address); + if (unlikely(!folio_test_anon(folio))) { + VM_WARN_ON_FOLIO(!folio_test_locked(folio), folio); + /* + * For a PTE-mapped large folio, we only know that the single + * PTE is exclusive. Further, __folio_set_anon() might not get + * folio->index right when not given the address of the head + * page. + */ + VM_WARN_ON_FOLIO(folio_test_large(folio) && !compound, folio); + __folio_set_anon(folio, vma, address, + !!(flags & RMAP_EXCLUSIVE)); + } else if (likely(!folio_test_ksm(folio))) { + __page_check_anon_rmap(folio, page, vma, address); } + if (flags & RMAP_EXCLUSIVE) + SetPageAnonExclusive(page); + /* While PTE-mapping a THP we have a PMD and a PTE mapping. */ + VM_WARN_ON_FOLIO((atomic_read(&page->_mapcount) > 0 || + (folio_test_large(folio) && folio_entire_mapcount(folio) > 1)) && + PageAnonExclusive(page), folio); - mlock_vma_folio(folio, vma, compound); + /* + * For large folio, only mlock it if it's fully mapped to VMA. It's + * not easy to check whether the large folio is fully mapped to VMA + * here. Only mlock normal 4K folio and leave page reclaim to handle + * large folio. + */ + if (!folio_test_large(folio)) + mlock_vma_folio(folio, vma); } /** @@ -1290,7 +1329,8 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, } __lruvec_stat_mod_folio(folio, NR_ANON_MAPPED, nr); - __page_set_anon_rmap(folio, &folio->page, vma, address, 1); + __folio_set_anon(folio, vma, address, true); + SetPageAnonExclusive(&folio->page); } /** @@ -1352,7 +1392,9 @@ void folio_add_file_rmap_range(struct folio *folio, struct page *page, if (nr) __lruvec_stat_mod_folio(folio, NR_FILE_MAPPED, nr); - mlock_vma_folio(folio, vma, compound); + /* See comments in page_add_anon_rmap() */ + if (!folio_test_large(folio)) + mlock_vma_folio(folio, vma); } /** @@ -1463,7 +1505,7 @@ void page_remove_rmap(struct page *page, struct vm_area_struct *vma, * it's only reliable while mapped. */ - munlock_vma_folio(folio, vma, compound); + munlock_vma_folio(folio, vma); } /* @@ -1528,7 +1570,8 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma, if (!(flags & TTU_IGNORE_MLOCK) && (vma->vm_flags & VM_LOCKED)) { /* Restore the mlock which got missed */ - mlock_vma_folio(folio, vma, false); + if (!folio_test_large(folio)) + mlock_vma_folio(folio, vma); page_vma_mapped_walk_done(&pvmw); ret = false; break; @@ -2540,22 +2583,16 @@ void rmap_walk_locked(struct folio *folio, struct rmap_walk_control *rwc) * * RMAP_COMPOUND is ignored. */ -void hugepage_add_anon_rmap(struct page *page, struct vm_area_struct *vma, +void hugepage_add_anon_rmap(struct folio *folio, struct vm_area_struct *vma, unsigned long address, rmap_t flags) { - struct folio *folio = page_folio(page); - struct anon_vma *anon_vma = vma->anon_vma; - int first; + VM_WARN_ON_FOLIO(!folio_test_anon(folio), folio); - BUG_ON(!folio_test_locked(folio)); - BUG_ON(!anon_vma); - /* address might be in next vma when migration races vma_merge */ - first = atomic_inc_and_test(&folio->_entire_mapcount); - VM_BUG_ON_PAGE(!first && (flags & RMAP_EXCLUSIVE), page); - VM_BUG_ON_PAGE(!first && PageAnonExclusive(page), page); - if (first) - __page_set_anon_rmap(folio, page, vma, address, - !!(flags & RMAP_EXCLUSIVE)); + atomic_inc(&folio->_entire_mapcount); + if (flags & RMAP_EXCLUSIVE) + SetPageAnonExclusive(&folio->page); + VM_WARN_ON_FOLIO(folio_entire_mapcount(folio) > 1 && + PageAnonExclusive(&folio->page), folio); } void hugepage_add_new_anon_rmap(struct folio *folio, @@ -2565,6 +2602,7 @@ void hugepage_add_new_anon_rmap(struct folio *folio, /* increment count (starts at -1) */ atomic_set(&folio->_entire_mapcount, 0); folio_clear_hugetlb_restore_reserve(folio); - __page_set_anon_rmap(folio, &folio->page, vma, address, 1); + __folio_set_anon(folio, vma, address, true); + SetPageAnonExclusive(&folio->page); } #endif /* CONFIG_HUGETLB_PAGE */ |