From 3047250972ff935b1d7a0629fa3acb04c12dcc07 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Thu, 2 Sep 2021 14:53:18 -0700 Subject: [PATCH] mm: remove irqsave/restore locking from contexts with irqs enabled The page cache deletion paths all have interrupts enabled, so no need to use irqsafe/irqrestore locking variants. They used to have irqs disabled by the memcg lock added in commit c4843a7593a9 ("memcg: add per cgroup dirty page accounting"), but that has since been replaced by memcg taking the page lock instead, commit 0a31bc97c80c ("mm: memcontrol: rewrite uncharge AP"). Link: https://lkml.kernel.org/r/20210614211904.14420-1-hannes@cmpxchg.org Signed-off-by: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/filemap.c | 15 ++++++--------- mm/truncate.c | 8 +++----- mm/vmscan.c | 9 ++++----- 3 files changed, 13 insertions(+), 19 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index d1458ec..4926f16 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -258,12 +258,11 @@ static void page_cache_free_page(struct address_space *mapping, void delete_from_page_cache(struct page *page) { struct address_space *mapping = page_mapping(page); - unsigned long flags; BUG_ON(!PageLocked(page)); - xa_lock_irqsave(&mapping->i_pages, flags); + xa_lock_irq(&mapping->i_pages); __delete_from_page_cache(page, NULL); - xa_unlock_irqrestore(&mapping->i_pages, flags); + xa_unlock_irq(&mapping->i_pages); page_cache_free_page(mapping, page); } @@ -335,19 +334,18 @@ void delete_from_page_cache_batch(struct address_space *mapping, struct pagevec *pvec) { int i; - unsigned long flags; if (!pagevec_count(pvec)) return; - xa_lock_irqsave(&mapping->i_pages, flags); + xa_lock_irq(&mapping->i_pages); for (i = 0; i < pagevec_count(pvec); i++) { trace_mm_filemap_delete_from_page_cache(pvec->pages[i]); unaccount_page_cache_page(mapping, pvec->pages[i]); } page_cache_delete_batch(mapping, pvec); - xa_unlock_irqrestore(&mapping->i_pages, flags); + xa_unlock_irq(&mapping->i_pages); for (i = 0; i < pagevec_count(pvec); i++) page_cache_free_page(mapping, pvec->pages[i]); @@ -821,7 +819,6 @@ void replace_page_cache_page(struct page *old, struct page *new) void (*freepage)(struct page *) = mapping->a_ops->freepage; pgoff_t offset = old->index; XA_STATE(xas, &mapping->i_pages, offset); - unsigned long flags; VM_BUG_ON_PAGE(!PageLocked(old), old); VM_BUG_ON_PAGE(!PageLocked(new), new); @@ -833,7 +830,7 @@ void replace_page_cache_page(struct page *old, struct page *new) mem_cgroup_migrate(old, new); - xas_lock_irqsave(&xas, flags); + xas_lock_irq(&xas); xas_store(&xas, new); old->mapping = NULL; @@ -846,7 +843,7 @@ void replace_page_cache_page(struct page *old, struct page *new) __dec_lruvec_page_state(old, NR_SHMEM); if (PageSwapBacked(new)) __inc_lruvec_page_state(new, NR_SHMEM); - xas_unlock_irqrestore(&xas, flags); + xas_unlock_irq(&xas); if (freepage) freepage(old); put_page(old); diff --git a/mm/truncate.c b/mm/truncate.c index 234ddd8..2adff8f 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -560,21 +560,19 @@ void invalidate_mapping_pagevec(struct address_space *mapping, static int invalidate_complete_page2(struct address_space *mapping, struct page *page) { - unsigned long flags; - if (page->mapping != mapping) return 0; if (page_has_private(page) && !try_to_release_page(page, GFP_KERNEL)) return 0; - xa_lock_irqsave(&mapping->i_pages, flags); + xa_lock_irq(&mapping->i_pages); if (PageDirty(page)) goto failed; BUG_ON(page_has_private(page)); __delete_from_page_cache(page, NULL); - xa_unlock_irqrestore(&mapping->i_pages, flags); + xa_unlock_irq(&mapping->i_pages); if (mapping->a_ops->freepage) mapping->a_ops->freepage(page); @@ -582,7 +580,7 @@ invalidate_complete_page2(struct address_space *mapping, struct page *page) put_page(page); /* pagecache ref */ return 1; failed: - xa_unlock_irqrestore(&mapping->i_pages, flags); + xa_unlock_irq(&mapping->i_pages); return 0; } diff --git a/mm/vmscan.c b/mm/vmscan.c index 17c4b3f..268ad65 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1052,14 +1052,13 @@ static pageout_t pageout(struct page *page, struct address_space *mapping) static int __remove_mapping(struct address_space *mapping, struct page *page, bool reclaimed, struct mem_cgroup *target_memcg) { - unsigned long flags; int refcount; void *shadow = NULL; BUG_ON(!PageLocked(page)); BUG_ON(mapping != page_mapping(page)); - xa_lock_irqsave(&mapping->i_pages, flags); + xa_lock_irq(&mapping->i_pages); /* * The non racy check for a busy page. * @@ -1100,7 +1099,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page, if (reclaimed && !mapping_exiting(mapping)) shadow = workingset_eviction(page, target_memcg); __delete_from_swap_cache(page, swap, shadow); - xa_unlock_irqrestore(&mapping->i_pages, flags); + xa_unlock_irq(&mapping->i_pages); put_swap_page(page, swap); } else { void (*freepage)(struct page *); @@ -1126,7 +1125,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page, !mapping_exiting(mapping) && !dax_mapping(mapping)) shadow = workingset_eviction(page, target_memcg); __delete_from_page_cache(page, shadow); - xa_unlock_irqrestore(&mapping->i_pages, flags); + xa_unlock_irq(&mapping->i_pages); if (freepage != NULL) freepage(page); @@ -1135,7 +1134,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page, return 1; cannot_free: - xa_unlock_irqrestore(&mapping->i_pages, flags); + xa_unlock_irq(&mapping->i_pages); return 0; } -- 2.7.4