diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/debug.c | 5 | ||||
| -rw-r--r-- | mm/huge_memory.c | 2 | ||||
| -rw-r--r-- | mm/hugetlb.c | 4 | ||||
| -rw-r--r-- | mm/memcontrol.c | 8 | ||||
| -rw-r--r-- | mm/memory.c | 2 | ||||
| -rw-r--r-- | mm/migrate.c | 2 | ||||
| -rw-r--r-- | mm/page_alloc.c | 13 | ||||
| -rw-r--r-- | mm/rmap.c | 98 |
8 files changed, 103 insertions, 31 deletions
diff --git a/mm/debug.c b/mm/debug.c index 03c9a13f9f6a..f05b2d5d6481 100644 --- a/mm/debug.c +++ b/mm/debug.c @@ -79,9 +79,12 @@ static void dump_flags(unsigned long flags, void dump_page_badflags(struct page *page, const char *reason, unsigned long badflags) { - pr_emerg("page:%p count:%d mapcount:%d mapping:%p index:%#lx\n", + pr_emerg("page:%p count:%d mapcount:%d mapping:%p index:%#lx", page, atomic_read(&page->_count), page_mapcount(page), page->mapping, page->index); + if (PageCompound(page)) + pr_cont(" compound_mapcount: %d", compound_mapcount(page)); + pr_cont("\n"); BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS); dump_flags(page->flags, pageflag_names, ARRAY_SIZE(pageflag_names)); if (reason) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 1de7ab5d1004..1588f688b75d 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -989,7 +989,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm, src_page = pmd_page(pmd); VM_BUG_ON_PAGE(!PageHead(src_page), src_page); get_page(src_page); - page_dup_rmap(src_page); + page_dup_rmap(src_page, true); add_mm_counter(dst_mm, MM_ANONPAGES, HPAGE_PMD_NR); pmdp_set_wrprotect(src_mm, addr, src_pmd); diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 84af842e828d..12908dcf5831 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3102,7 +3102,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, entry = huge_ptep_get(src_pte); ptepage = pte_page(entry); get_page(ptepage); - page_dup_rmap(ptepage); + page_dup_rmap(ptepage, true); set_huge_pte_at(dst, addr, dst_pte, entry); hugetlb_count_add(pages_per_huge_page(h), dst); } @@ -3585,7 +3585,7 @@ retry: ClearPagePrivate(page); hugepage_add_new_anon_rmap(page, vma, address); } else - page_dup_rmap(page); + page_dup_rmap(page, true); new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE) && (vma->vm_flags & VM_SHARED))); set_huge_pte_at(mm, address, ptep, new_pte); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 3b8c845e0c2e..bee6b1c9fdce 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4899,6 +4899,14 @@ retry: switch (get_mctgt_type(vma, addr, ptent, &target)) { case MC_TARGET_PAGE: page = target.page; + /* + * We can have a part of the split pmd here. Moving it + * can be done but it would be too convoluted so simply + * ignore such a partial THP and keep it in original + * memcg. There should be somebody mapping the head. + */ + if (PageTransCompound(page)) + goto put; if (isolate_lru_page(page)) goto put; if (!mem_cgroup_move_account(page, false, diff --git a/mm/memory.c b/mm/memory.c index 3b656d1a8e07..9b0dbc2f0b9a 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -864,7 +864,7 @@ copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, page = vm_normal_page(vma, addr, pte); if (page) { get_page(page); - page_dup_rmap(page); + page_dup_rmap(page, false); rss[mm_counter(page)]++; } diff --git a/mm/migrate.c b/mm/migrate.c index 3921f20f8de4..91545da23fd1 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -165,7 +165,7 @@ static int remove_migration_pte(struct page *new, struct vm_area_struct *vma, if (PageAnon(new)) hugepage_add_anon_rmap(new, vma, addr); else - page_dup_rmap(new); + page_dup_rmap(new, true); } else if (PageAnon(new)) page_add_anon_rmap(new, vma, addr, false); else diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d02d6436add0..3221091da513 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -469,6 +469,7 @@ void prep_compound_page(struct page *page, unsigned int order) p->mapping = TAIL_MAPPING; set_compound_head(p, page); } + atomic_set(compound_mapcount_ptr(page), -1); } #ifdef CONFIG_DEBUG_PAGEALLOC @@ -733,7 +734,7 @@ static inline int free_pages_check(struct page *page) const char *bad_reason = NULL; unsigned long bad_flags = 0; - if (unlikely(page_mapcount(page))) + if (unlikely(atomic_read(&page->_mapcount) != -1)) bad_reason = "nonzero mapcount"; if (unlikely(page->mapping != NULL)) bad_reason = "non-NULL mapping"; @@ -857,7 +858,13 @@ static int free_tail_pages_check(struct page *head_page, struct page *page) ret = 0; goto out; } - if (page->mapping != TAIL_MAPPING) { + /* mapping in first tail page is used for compound_mapcount() */ + if (page - head_page == 1) { + if (unlikely(compound_mapcount(page))) { + bad_page(page, "nonzero compound_mapcount", 0); + goto out; + } + } else if (page->mapping != TAIL_MAPPING) { bad_page(page, "corrupted mapping in tail page", 0); goto out; } @@ -1335,7 +1342,7 @@ static inline int check_new_page(struct page *page) const char *bad_reason = NULL; unsigned long bad_flags = 0; - if (unlikely(page_mapcount(page))) + if (unlikely(atomic_read(&page->_mapcount) != -1)) bad_reason = "nonzero mapcount"; if (unlikely(page->mapping != NULL)) bad_reason = "non-NULL mapping"; diff --git a/mm/rmap.c b/mm/rmap.c index aa68a4089a53..2e6257165527 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1122,7 +1122,7 @@ static void __page_check_anon_rmap(struct page *page, * over the call to page_add_new_anon_rmap. */ BUG_ON(page_anon_vma(page)->root != vma->anon_vma->root); - BUG_ON(page->index != linear_page_index(vma, address)); + BUG_ON(page_to_pgoff(page) != linear_page_index(vma, address)); #endif } @@ -1152,9 +1152,28 @@ void page_add_anon_rmap(struct page *page, void do_page_add_anon_rmap(struct page *page, struct vm_area_struct *vma, unsigned long address, int flags) { - int first = atomic_inc_and_test(&page->_mapcount); + bool compound = flags & RMAP_COMPOUND; + bool first; + + if (PageTransCompound(page)) { + VM_BUG_ON_PAGE(!PageLocked(page), page); + if (compound) { + atomic_t *mapcount; + + VM_BUG_ON_PAGE(!PageTransHuge(page), page); + mapcount = compound_mapcount_ptr(page); + first = atomic_inc_and_test(mapcount); + } else { + /* Anon THP always mapped first with PMD */ + first = 0; + VM_BUG_ON_PAGE(!page_mapcount(page), page); + atomic_inc(&page->_mapcount); + } + } else { + first = atomic_inc_and_test(&page->_mapcount); + } + if (first) { - bool compound = flags & RMAP_COMPOUND; int nr = compound ? hpage_nr_pages(page) : 1; /* * We use the irq-unsafe __{inc|mod}_zone_page_stat because @@ -1173,6 +1192,7 @@ void do_page_add_anon_rmap(struct page *page, return; VM_BUG_ON_PAGE(!PageLocked(page), page); + /* address might be in next vma when migration races vma_adjust */ if (first) __page_set_anon_rmap(page, vma, address, @@ -1199,10 +1219,16 @@ void page_add_new_anon_rmap(struct page *page, VM_BUG_ON_VMA(address < vma->vm_start || address >= vma->vm_end, vma); SetPageSwapBacked(page); - atomic_set(&page->_mapcount, 0); /* increment count (starts at -1) */ if (compound) { VM_BUG_ON_PAGE(!PageTransHuge(page), page); + /* increment count (starts at -1) */ + atomic_set(compound_mapcount_ptr(page), 0); __inc_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES); + } else { + /* Anon THP always mapped first with PMD */ + VM_BUG_ON_PAGE(PageTransCompound(page), page); + /* increment count (starts at -1) */ + atomic_set(&page->_mapcount, 0); } __mod_zone_page_state(page_zone(page), NR_ANON_PAGES, nr); __page_set_anon_rmap(page, vma, address, 1); @@ -1232,12 +1258,15 @@ static void page_remove_file_rmap(struct page *page) memcg = mem_cgroup_begin_page_stat(page); - /* page still mapped by someone else? */ - if (!atomic_add_negative(-1, &page->_mapcount)) + /* Hugepages are not counted in NR_FILE_MAPPED for now. */ + if (unlikely(PageHuge(page))) { + /* hugetlb pages are always mapped with pmds */ + atomic_dec(compound_mapcount_ptr(page)); goto out; + } - /* Hugepages are not counted in NR_FILE_MAPPED for now. */ - if (unlikely(PageHuge(page))) + /* page still mapped by someone else? */ + if (!atomic_add_negative(-1, &page->_mapcount)) goto out; /* @@ -1254,6 +1283,39 @@ out: mem_cgroup_end_page_stat(memcg); } +static void page_remove_anon_compound_rmap(struct page *page) +{ + int i, nr; + + if (!atomic_add_negative(-1, compound_mapcount_ptr(page))) + return; + + /* Hugepages are not counted in NR_ANON_PAGES for now. */ + if (unlikely(PageHuge(page))) + return; + + if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) + return; + + __dec_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES); + + if (TestClearPageDoubleMap(page)) { + /* + * Subpages can be mapped with PTEs too. Check how many of + * themi are still mapped. + */ + for (i = 0, nr = 0; i < HPAGE_PMD_NR; i++) { + if (atomic_add_negative(-1, &page[i]._mapcount)) + nr++; + } + } else { + nr = HPAGE_PMD_NR; + } + + if (nr) + __mod_zone_page_state(page_zone(page), NR_ANON_PAGES, -nr); +} + /** * page_remove_rmap - take down pte mapping from a page * @page: page to remove mapping from @@ -1263,33 +1325,25 @@ out: */ void page_remove_rmap(struct page *page, bool compound) { - int nr = compound ? hpage_nr_pages(page) : 1; - if (!PageAnon(page)) { VM_BUG_ON_PAGE(compound && !PageHuge(page), page); page_remove_file_rmap(page); return; } + if (compound) + return page_remove_anon_compound_rmap(page); + /* page still mapped by someone else? */ if (!atomic_add_negative(-1, &page->_mapcount)) return; - /* Hugepages are not counted in NR_ANON_PAGES for now. */ - if (unlikely(PageHuge(page))) - return; - /* * We use the irq-unsafe __{inc|mod}_zone_page_stat because * these counters are not modified in interrupt context, and * pte lock(a spinlock) is held, which implies preemption disabled. */ - if (compound) { - VM_BUG_ON_PAGE(!PageTransHuge(page), page); - __dec_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES); - } - - __mod_zone_page_state(page_zone(page), NR_ANON_PAGES, -nr); + __dec_zone_page_state(page, NR_ANON_PAGES); if (unlikely(PageMlocked(page))) clear_page_mlock(page); @@ -1710,7 +1764,7 @@ void hugepage_add_anon_rmap(struct page *page, BUG_ON(!PageLocked(page)); BUG_ON(!anon_vma); /* address might be in next vma when migration races vma_adjust */ - first = atomic_inc_and_test(&page->_mapcount); + first = atomic_inc_and_test(compound_mapcount_ptr(page)); if (first) __hugepage_set_anon_rmap(page, vma, address, 0); } @@ -1719,7 +1773,7 @@ void hugepage_add_new_anon_rmap(struct page *page, struct vm_area_struct *vma, unsigned long address) { BUG_ON(address < vma->vm_start || address >= vma->vm_end); - atomic_set(&page->_mapcount, 0); + atomic_set(compound_mapcount_ptr(page), 0); __hugepage_set_anon_rmap(page, vma, address, 1); } #endif /* CONFIG_HUGETLB_PAGE */ |