[PATCH 8/8] mm: Hoist find_subpage call further up in pagecache_get_page
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Date: 2020-08-19 18:49:47
Also in:
intel-gfx, linux-mm, lkml
Subsystem:
memory management, page cache, the rest · Maintainers:
Andrew Morton, Matthew Wilcox, Linus Torvalds
This avoids a call to compound_head(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- mm/filemap.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/mm/filemap.c b/mm/filemap.c
index 6594baae7cd2..8c354277108d 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c@@ -1667,7 +1667,6 @@ struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, page = NULL; if (!page) goto no_page; - page = find_subpage(page, index); if (fgp_flags & FGP_LOCK) { if (fgp_flags & FGP_NOWAIT) {
@@ -1680,12 +1679,12 @@ struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, } /* Has the page been truncated? */ - if (unlikely(compound_head(page)->mapping != mapping)) { + if (unlikely(page->mapping != mapping)) { unlock_page(page); put_page(page); goto repeat; } - VM_BUG_ON_PAGE(page->index != index, page); + VM_BUG_ON_PAGE(!thp_valid_index(page, index), page); } if (fgp_flags & FGP_ACCESSED)
@@ -1695,6 +1694,7 @@ struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, if (page_is_idle(page)) clear_page_idle(page); } + page = find_subpage(page, index); no_page: if (!page && (fgp_flags & FGP_CREAT)) {
--
2.28.0