Message ID | 20240613000721.23093-2-21cnbao@gmail.com (mailing list archive) |
---|---|
State | New |
Headers | show |
Series | mm: clarify folio_add_new_anon_rmap() and __folio_add_anon_rmap() | expand |
On Thu, Jun 13, 2024 at 12:07 PM Barry Song <21cnbao@gmail.com> wrote: > > From: Barry Song <v-songbaohua@oppo.com> > > In the case of do_swap_page(), a new anonymous folio isn’t necessarily > exclusive. This patch extends the rmap flags to allow treating a new > anon folio as either exclusive or non-exclusive. To maintain the current > behavior, we always use EXCLUSIVE as arguments. > > Suggested-by: David Hildenbrand <david@redhat.com> > Signed-off-by: Barry Song <v-songbaohua@oppo.com> > --- > include/linux/rmap.h | 2 +- > kernel/events/uprobes.c | 2 +- > mm/huge_memory.c | 2 +- > mm/khugepaged.c | 2 +- > mm/memory.c | 10 +++++----- > mm/migrate_device.c | 2 +- > mm/rmap.c | 15 +++++++++------ > mm/swapfile.c | 2 +- > mm/userfaultfd.c | 2 +- > 9 files changed, 21 insertions(+), 18 deletions(-) > > diff --git a/include/linux/rmap.h b/include/linux/rmap.h > index cae38a2a643d..01a64e7e72b9 100644 > --- a/include/linux/rmap.h > +++ b/include/linux/rmap.h > @@ -244,7 +244,7 @@ void folio_add_anon_rmap_ptes(struct folio *, struct page *, int nr_pages, > void folio_add_anon_rmap_pmd(struct folio *, struct page *, > struct vm_area_struct *, unsigned long address, rmap_t flags); > void folio_add_new_anon_rmap(struct folio *, struct vm_area_struct *, > - unsigned long address); > + unsigned long address, rmap_t flags); > void folio_add_file_rmap_ptes(struct folio *, struct page *, int nr_pages, > struct vm_area_struct *); > #define folio_add_file_rmap_pte(folio, page, vma) \ > diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c > index 2c83ba776fc7..c20368aa33dd 100644 > --- a/kernel/events/uprobes.c > +++ b/kernel/events/uprobes.c > @@ -181,7 +181,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, > > if (new_page) { > folio_get(new_folio); > - folio_add_new_anon_rmap(new_folio, vma, addr); > + folio_add_new_anon_rmap(new_folio, vma, addr, RMAP_EXCLUSIVE); > folio_add_lru_vma(new_folio, vma); > } else > /* no new page, just dec_mm_counter for old_page */ > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index f409ea9fcc18..09a83e43c71a 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -973,7 +973,7 @@ static vm_fault_t __do_huge_pmd_anonymous_page(struct vm_fault *vmf, > > entry = mk_huge_pmd(page, vma->vm_page_prot); > entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); > - folio_add_new_anon_rmap(folio, vma, haddr); > + folio_add_new_anon_rmap(folio, vma, haddr, RMAP_EXCLUSIVE); > folio_add_lru_vma(folio, vma); > pgtable_trans_huge_deposit(vma->vm_mm, vmf->pmd, pgtable); > set_pmd_at(vma->vm_mm, haddr, vmf->pmd, entry); > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > index 774a97e6e2da..4d759a7487d0 100644 > --- a/mm/khugepaged.c > +++ b/mm/khugepaged.c > @@ -1213,7 +1213,7 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address, > > spin_lock(pmd_ptl); > BUG_ON(!pmd_none(*pmd)); > - folio_add_new_anon_rmap(folio, vma, address); > + folio_add_new_anon_rmap(folio, vma, address, RMAP_EXCLUSIVE); > folio_add_lru_vma(folio, vma); > pgtable_trans_huge_deposit(mm, pmd, pgtable); > set_pmd_at(mm, address, pmd, _pmd); > diff --git a/mm/memory.c b/mm/memory.c > index 54d7d2acdf39..2f94921091fb 100644 > --- a/mm/memory.c > +++ b/mm/memory.c > @@ -930,7 +930,7 @@ copy_present_page(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma > *prealloc = NULL; > copy_user_highpage(&new_folio->page, page, addr, src_vma); > __folio_mark_uptodate(new_folio); > - folio_add_new_anon_rmap(new_folio, dst_vma, addr); > + folio_add_new_anon_rmap(new_folio, dst_vma, addr, RMAP_EXCLUSIVE); > folio_add_lru_vma(new_folio, dst_vma); > rss[MM_ANONPAGES]++; > > @@ -3400,7 +3400,7 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf) > * some TLBs while the old PTE remains in others. > */ > ptep_clear_flush(vma, vmf->address, vmf->pte); > - folio_add_new_anon_rmap(new_folio, vma, vmf->address); > + folio_add_new_anon_rmap(new_folio, vma, vmf->address, RMAP_EXCLUSIVE); > folio_add_lru_vma(new_folio, vma); > BUG_ON(unshare && pte_write(entry)); > set_pte_at(mm, vmf->address, vmf->pte, entry); > @@ -4337,7 +4337,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) > > /* ksm created a completely new copy */ > if (unlikely(folio != swapcache && swapcache)) { > - folio_add_new_anon_rmap(folio, vma, address); > + folio_add_new_anon_rmap(folio, vma, address, RMAP_EXCLUSIVE); > folio_add_lru_vma(folio, vma); > } else { > folio_add_anon_rmap_ptes(folio, page, nr_pages, vma, address, > @@ -4592,7 +4592,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf) > #ifdef CONFIG_TRANSPARENT_HUGEPAGE > count_mthp_stat(folio_order(folio), MTHP_STAT_ANON_FAULT_ALLOC); > #endif > - folio_add_new_anon_rmap(folio, vma, addr); > + folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); > folio_add_lru_vma(folio, vma); > setpte: > if (vmf_orig_pte_uffd_wp(vmf)) > @@ -4790,7 +4790,7 @@ void set_pte_range(struct vm_fault *vmf, struct folio *folio, > /* copy-on-write page */ > if (write && !(vma->vm_flags & VM_SHARED)) { > VM_BUG_ON_FOLIO(nr != 1, folio); > - folio_add_new_anon_rmap(folio, vma, addr); > + folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); > folio_add_lru_vma(folio, vma); > } else { > folio_add_file_rmap_ptes(folio, page, nr, vma); > diff --git a/mm/migrate_device.c b/mm/migrate_device.c > index 051d0a3ccbee..6d66dc1c6ffa 100644 > --- a/mm/migrate_device.c > +++ b/mm/migrate_device.c > @@ -658,7 +658,7 @@ static void migrate_vma_insert_page(struct migrate_vma *migrate, > goto unlock_abort; > > inc_mm_counter(mm, MM_ANONPAGES); > - folio_add_new_anon_rmap(folio, vma, addr); > + folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); > if (!folio_is_zone_device(folio)) > folio_add_lru_vma(folio, vma); > folio_get(folio); > diff --git a/mm/rmap.c b/mm/rmap.c > index b9e5943c8349..e612d999811a 100644 > --- a/mm/rmap.c > +++ b/mm/rmap.c > @@ -1406,14 +1406,14 @@ void folio_add_anon_rmap_pmd(struct folio *folio, struct page *page, > * This means the inc-and-test can be bypassed. > * The folio does not have to be locked. > * > - * If the folio is pmd-mappable, it is accounted as a THP. As the folio > - * is new, it's assumed to be mapped exclusively by a single process. > + * If the folio is pmd-mappable, it is accounted as a THP. > */ > void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, > - unsigned long address) > + unsigned long address, rmap_t flags) > { > int nr = folio_nr_pages(folio); > int nr_pmdmapped = 0; > + bool exclusive = flags & RMAP_EXCLUSIVE; > > VM_WARN_ON_FOLIO(folio_test_hugetlb(folio), folio); > VM_BUG_ON_VMA(address < vma->vm_start || > @@ -1424,7 +1424,8 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, > if (likely(!folio_test_large(folio))) { > /* increment count (starts at -1) */ > atomic_set(&folio->_mapcount, 0); > - SetPageAnonExclusive(&folio->page); > + if (exclusive) > + SetPageAnonExclusive(&folio->page); > } else if (!folio_test_pmd_mappable(folio)) { > int i; > > @@ -1433,7 +1434,8 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, > > /* increment count (starts at -1) */ > atomic_set(&page->_mapcount, 0); > - SetPageAnonExclusive(page); > + if (exclusive) > + SetPageAnonExclusive(page); > } > > /* increment count (starts at -1) */ > @@ -1445,7 +1447,8 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, > /* increment count (starts at -1) */ > atomic_set(&folio->_large_mapcount, 0); > atomic_set(&folio->_nr_pages_mapped, ENTIRELY_MAPPED); > - SetPageAnonExclusive(&folio->page); > + if (exclusive) > + SetPageAnonExclusive(&folio->page); > nr_pmdmapped = nr; > } > I am lacking this: --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1408,7 +1408,7 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, VM_BUG_ON_VMA(address < vma->vm_start || address + (nr << PAGE_SHIFT) > vma->vm_end, vma); __folio_set_swapbacked(folio); - __folio_set_anon(folio, vma, address, true); + __folio_set_anon(folio, vma, address, exclusive); if (likely(!folio_test_large(folio))) { /* increment count (starts at -1) */ > diff --git a/mm/swapfile.c b/mm/swapfile.c > index 9c6d8e557c0f..ae1d2700f6a3 100644 > --- a/mm/swapfile.c > +++ b/mm/swapfile.c > @@ -1911,7 +1911,7 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd, > > folio_add_anon_rmap_pte(folio, page, vma, addr, rmap_flags); > } else { /* ksm created a completely new copy */ > - folio_add_new_anon_rmap(folio, vma, addr); > + folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); > folio_add_lru_vma(folio, vma); > } > new_pte = pte_mkold(mk_pte(page, vma->vm_page_prot)); > diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c > index 5e7f2801698a..8dedaec00486 100644 > --- a/mm/userfaultfd.c > +++ b/mm/userfaultfd.c > @@ -216,7 +216,7 @@ int mfill_atomic_install_pte(pmd_t *dst_pmd, > folio_add_lru(folio); > folio_add_file_rmap_pte(folio, page, dst_vma); > } else { > - folio_add_new_anon_rmap(folio, dst_vma, dst_addr); > + folio_add_new_anon_rmap(folio, dst_vma, dst_addr, RMAP_EXCLUSIVE); > folio_add_lru_vma(folio, dst_vma); > } > > -- > 2.34.1 >
diff --git a/include/linux/rmap.h b/include/linux/rmap.h index cae38a2a643d..01a64e7e72b9 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -244,7 +244,7 @@ void folio_add_anon_rmap_ptes(struct folio *, struct page *, int nr_pages, void folio_add_anon_rmap_pmd(struct folio *, struct page *, struct vm_area_struct *, unsigned long address, rmap_t flags); void folio_add_new_anon_rmap(struct folio *, struct vm_area_struct *, - unsigned long address); + unsigned long address, rmap_t flags); void folio_add_file_rmap_ptes(struct folio *, struct page *, int nr_pages, struct vm_area_struct *); #define folio_add_file_rmap_pte(folio, page, vma) \ diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 2c83ba776fc7..c20368aa33dd 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -181,7 +181,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, if (new_page) { folio_get(new_folio); - folio_add_new_anon_rmap(new_folio, vma, addr); + folio_add_new_anon_rmap(new_folio, vma, addr, RMAP_EXCLUSIVE); folio_add_lru_vma(new_folio, vma); } else /* no new page, just dec_mm_counter for old_page */ diff --git a/mm/huge_memory.c b/mm/huge_memory.c index f409ea9fcc18..09a83e43c71a 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -973,7 +973,7 @@ static vm_fault_t __do_huge_pmd_anonymous_page(struct vm_fault *vmf, entry = mk_huge_pmd(page, vma->vm_page_prot); entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); - folio_add_new_anon_rmap(folio, vma, haddr); + folio_add_new_anon_rmap(folio, vma, haddr, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); pgtable_trans_huge_deposit(vma->vm_mm, vmf->pmd, pgtable); set_pmd_at(vma->vm_mm, haddr, vmf->pmd, entry); diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 774a97e6e2da..4d759a7487d0 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -1213,7 +1213,7 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address, spin_lock(pmd_ptl); BUG_ON(!pmd_none(*pmd)); - folio_add_new_anon_rmap(folio, vma, address); + folio_add_new_anon_rmap(folio, vma, address, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); pgtable_trans_huge_deposit(mm, pmd, pgtable); set_pmd_at(mm, address, pmd, _pmd); diff --git a/mm/memory.c b/mm/memory.c index 54d7d2acdf39..2f94921091fb 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -930,7 +930,7 @@ copy_present_page(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma *prealloc = NULL; copy_user_highpage(&new_folio->page, page, addr, src_vma); __folio_mark_uptodate(new_folio); - folio_add_new_anon_rmap(new_folio, dst_vma, addr); + folio_add_new_anon_rmap(new_folio, dst_vma, addr, RMAP_EXCLUSIVE); folio_add_lru_vma(new_folio, dst_vma); rss[MM_ANONPAGES]++; @@ -3400,7 +3400,7 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf) * some TLBs while the old PTE remains in others. */ ptep_clear_flush(vma, vmf->address, vmf->pte); - folio_add_new_anon_rmap(new_folio, vma, vmf->address); + folio_add_new_anon_rmap(new_folio, vma, vmf->address, RMAP_EXCLUSIVE); folio_add_lru_vma(new_folio, vma); BUG_ON(unshare && pte_write(entry)); set_pte_at(mm, vmf->address, vmf->pte, entry); @@ -4337,7 +4337,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) /* ksm created a completely new copy */ if (unlikely(folio != swapcache && swapcache)) { - folio_add_new_anon_rmap(folio, vma, address); + folio_add_new_anon_rmap(folio, vma, address, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); } else { folio_add_anon_rmap_ptes(folio, page, nr_pages, vma, address, @@ -4592,7 +4592,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf) #ifdef CONFIG_TRANSPARENT_HUGEPAGE count_mthp_stat(folio_order(folio), MTHP_STAT_ANON_FAULT_ALLOC); #endif - folio_add_new_anon_rmap(folio, vma, addr); + folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); setpte: if (vmf_orig_pte_uffd_wp(vmf)) @@ -4790,7 +4790,7 @@ void set_pte_range(struct vm_fault *vmf, struct folio *folio, /* copy-on-write page */ if (write && !(vma->vm_flags & VM_SHARED)) { VM_BUG_ON_FOLIO(nr != 1, folio); - folio_add_new_anon_rmap(folio, vma, addr); + folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); } else { folio_add_file_rmap_ptes(folio, page, nr, vma); diff --git a/mm/migrate_device.c b/mm/migrate_device.c index 051d0a3ccbee..6d66dc1c6ffa 100644 --- a/mm/migrate_device.c +++ b/mm/migrate_device.c @@ -658,7 +658,7 @@ static void migrate_vma_insert_page(struct migrate_vma *migrate, goto unlock_abort; inc_mm_counter(mm, MM_ANONPAGES); - folio_add_new_anon_rmap(folio, vma, addr); + folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); if (!folio_is_zone_device(folio)) folio_add_lru_vma(folio, vma); folio_get(folio); diff --git a/mm/rmap.c b/mm/rmap.c index b9e5943c8349..e612d999811a 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1406,14 +1406,14 @@ void folio_add_anon_rmap_pmd(struct folio *folio, struct page *page, * This means the inc-and-test can be bypassed. * The folio does not have to be locked. * - * If the folio is pmd-mappable, it is accounted as a THP. As the folio - * is new, it's assumed to be mapped exclusively by a single process. + * If the folio is pmd-mappable, it is accounted as a THP. */ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, - unsigned long address) + unsigned long address, rmap_t flags) { int nr = folio_nr_pages(folio); int nr_pmdmapped = 0; + bool exclusive = flags & RMAP_EXCLUSIVE; VM_WARN_ON_FOLIO(folio_test_hugetlb(folio), folio); VM_BUG_ON_VMA(address < vma->vm_start || @@ -1424,7 +1424,8 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, if (likely(!folio_test_large(folio))) { /* increment count (starts at -1) */ atomic_set(&folio->_mapcount, 0); - SetPageAnonExclusive(&folio->page); + if (exclusive) + SetPageAnonExclusive(&folio->page); } else if (!folio_test_pmd_mappable(folio)) { int i; @@ -1433,7 +1434,8 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, /* increment count (starts at -1) */ atomic_set(&page->_mapcount, 0); - SetPageAnonExclusive(page); + if (exclusive) + SetPageAnonExclusive(page); } /* increment count (starts at -1) */ @@ -1445,7 +1447,8 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, /* increment count (starts at -1) */ atomic_set(&folio->_large_mapcount, 0); atomic_set(&folio->_nr_pages_mapped, ENTIRELY_MAPPED); - SetPageAnonExclusive(&folio->page); + if (exclusive) + SetPageAnonExclusive(&folio->page); nr_pmdmapped = nr; } diff --git a/mm/swapfile.c b/mm/swapfile.c index 9c6d8e557c0f..ae1d2700f6a3 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1911,7 +1911,7 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd, folio_add_anon_rmap_pte(folio, page, vma, addr, rmap_flags); } else { /* ksm created a completely new copy */ - folio_add_new_anon_rmap(folio, vma, addr); + folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); } new_pte = pte_mkold(mk_pte(page, vma->vm_page_prot)); diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 5e7f2801698a..8dedaec00486 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -216,7 +216,7 @@ int mfill_atomic_install_pte(pmd_t *dst_pmd, folio_add_lru(folio); folio_add_file_rmap_pte(folio, page, dst_vma); } else { - folio_add_new_anon_rmap(folio, dst_vma, dst_addr); + folio_add_new_anon_rmap(folio, dst_vma, dst_addr, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, dst_vma); }