From 4268b48077e55a93959f368aa9d3103ede5d3f0f Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Wed, 3 Mar 2021 15:21:55 -0500 Subject: [PATCH] mm/filemap: Add folio_end_writeback() Add an end_page_writeback() wrapper function for users that are not yet converted to folios. folio_end_writeback() is less than half the size of end_page_writeback() at just 105 bytes compared to 228 bytes, due to removing all the compound_head() calls. The 30 byte wrapper function makes this a net saving of 93 bytes. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Acked-by: Jeff Layton Acked-by: Kirill A. Shutemov Acked-by: Vlastimil Babka Reviewed-by: William Kucharski Reviewed-by: David Howells Acked-by: Mike Rapoport --- include/linux/pagemap.h | 3 ++- mm/filemap.c | 43 ++++++++++++++++++++--------------------- mm/folio-compat.c | 6 ++++++ 3 files changed, 29 insertions(+), 23 deletions(-) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 7cf140f98910..d9dcd335cc18 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -767,7 +767,8 @@ static inline int wait_on_page_locked_killable(struct page *page) int put_and_wait_on_page_locked(struct page *page, int state); void wait_on_page_writeback(struct page *page); int wait_on_page_writeback_killable(struct page *page); -extern void end_page_writeback(struct page *page); +void end_page_writeback(struct page *page); +void folio_end_writeback(struct folio *folio); void wait_for_stable_page(struct page *page); void __set_page_dirty(struct page *, struct address_space *, int warn); diff --git a/mm/filemap.c b/mm/filemap.c index 6a5bdb4f7c73..4e41bfdb6555 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1230,11 +1230,11 @@ static void wake_up_page_bit(struct page *page, int bit_nr) spin_unlock_irqrestore(&q->lock, flags); } -static void wake_up_page(struct page *page, int bit) +static void folio_wake(struct folio *folio, int bit) { - if (!PageWaiters(page)) + if (!folio_test_waiters(folio)) return; - wake_up_page_bit(page, bit); + wake_up_page_bit(&folio->page, bit); } /* @@ -1571,39 +1571,38 @@ int wait_on_page_private_2_killable(struct page *page) EXPORT_SYMBOL(wait_on_page_private_2_killable); /** - * end_page_writeback - end writeback against a page - * @page: the page + * folio_end_writeback - End writeback against a folio. + * @folio: The folio. */ -void end_page_writeback(struct page *page) +void folio_end_writeback(struct folio *folio) { /* - * TestClearPageReclaim could be used here but it is an atomic - * operation and overkill in this particular case. Failing to - * shuffle a page marked for immediate reclaim is too mild to - * justify taking an atomic operation penalty at the end of - * ever page writeback. + * folio_test_clear_reclaim() could be used here but it is an + * atomic operation and overkill in this particular case. Failing + * to shuffle a folio marked for immediate reclaim is too mild + * a gain to justify taking an atomic operation penalty at the + * end of every folio writeback. */ - if (PageReclaim(page)) { - struct folio *folio = page_folio(page); - ClearPageReclaim(page); + if (folio_test_reclaim(folio)) { + folio_clear_reclaim(folio); folio_rotate_reclaimable(folio); } /* - * Writeback does not hold a page reference of its own, relying + * Writeback does not hold a folio reference of its own, relying * on truncation to wait for the clearing of PG_writeback. - * But here we must make sure that the page is not freed and - * reused before the wake_up_page(). + * But here we must make sure that the folio is not freed and + * reused before the folio_wake(). */ - get_page(page); - if (!test_clear_page_writeback(page)) + folio_get(folio); + if (!test_clear_page_writeback(&folio->page)) BUG(); smp_mb__after_atomic(); - wake_up_page(page, PG_writeback); - put_page(page); + folio_wake(folio, PG_writeback); + folio_put(folio); } -EXPORT_SYMBOL(end_page_writeback); +EXPORT_SYMBOL(folio_end_writeback); /* * After completing I/O on a page, call this routine to update the page diff --git a/mm/folio-compat.c b/mm/folio-compat.c index 91b3d00a92f7..526843d03d58 100644 --- a/mm/folio-compat.c +++ b/mm/folio-compat.c @@ -17,3 +17,9 @@ void unlock_page(struct page *page) return folio_unlock(page_folio(page)); } EXPORT_SYMBOL(unlock_page); + +void end_page_writeback(struct page *page) +{ + return folio_end_writeback(page_folio(page)); +} +EXPORT_SYMBOL(end_page_writeback);