[PATCH v4 19/25] mm/page-writeback: Add wait_for_stable_folio
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Date: 2021-03-05 04:25:45
Also in:
linux-fsdevel, lkml
Subsystem:
memory management, memory management - core, page cache, the rest · Maintainers:
Andrew Morton, David Hildenbrand, Matthew Wilcox, Linus Torvalds
Move wait_for_stable_page() into the folio compatibility file. wait_for_stable_folio() avoids a call to compound_head() and is 14 bytes smaller than wait_for_stable_page() was. The net text size grows by 24 bytes as a result of this patch. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- include/linux/pagemap.h | 1 + mm/folio-compat.c | 6 ++++++ mm/page-writeback.c | 17 ++++++++--------- 3 files changed, 15 insertions(+), 9 deletions(-)
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 7d797847633c..e7ca8def2f0d 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h@@ -767,6 +767,7 @@ void wait_on_folio_writeback(struct folio *folio); void end_page_writeback(struct page *page); void end_folio_writeback(struct folio *folio); void wait_for_stable_page(struct page *page); +void wait_for_stable_folio(struct folio *folio); void page_endio(struct page *page, bool is_write, int err);
diff --git a/mm/folio-compat.c b/mm/folio-compat.c
index 6aadecc39fba..335594fe414e 100644
--- a/mm/folio-compat.c
+++ b/mm/folio-compat.c@@ -29,3 +29,9 @@ void wait_on_page_writeback(struct page *page) return wait_on_folio_writeback(page_folio(page)); } EXPORT_SYMBOL_GPL(wait_on_page_writeback); + +void wait_for_stable_page(struct page *page) +{ + return wait_for_stable_folio(page_folio(page)); +} +EXPORT_SYMBOL_GPL(wait_for_stable_page);
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 968579452ea4..eef36edc9e0c 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c@@ -2841,17 +2841,16 @@ void wait_on_folio_writeback(struct folio *folio) EXPORT_SYMBOL_GPL(wait_on_folio_writeback); /** - * wait_for_stable_page() - wait for writeback to finish, if necessary. - * @page: The page to wait on. + * wait_for_stable_folio() - wait for writeback to finish, if necessary. + * @folio: The folio to wait on. * - * This function determines if the given page is related to a backing device - * that requires page contents to be held stable during writeback. If so, then + * This function determines if the given folio is related to a backing device + * that requires folio contents to be held stable during writeback. If so, then * it will wait for any pending writeback to complete. */ -void wait_for_stable_page(struct page *page) +void wait_for_stable_folio(struct folio *folio) { - page = thp_head(page); - if (page->mapping->host->i_sb->s_iflags & SB_I_STABLE_WRITES) - wait_on_page_writeback(page); + if (folio->page.mapping->host->i_sb->s_iflags & SB_I_STABLE_WRITES) + wait_on_folio_writeback(folio); } -EXPORT_SYMBOL_GPL(wait_for_stable_page); +EXPORT_SYMBOL_GPL(wait_for_stable_folio);
--
2.30.0