From 23539afc71937dbaca7de2229669f4475ff4ea7b Mon Sep 17 00:00:00 2001 From: Wu Fengguang Date: Wed, 11 Aug 2010 14:17:41 -0700 Subject: [PATCH] writeback: don't redirty tail an inode with dirty pages Avoid delaying writeback for an expire inode with lots of dirty pages, but no active dirtier at the moment. Previously we only do that for the kupdate case. Any filesystem that does delayed allocation or unwritten extent conversion after IO completion will cause this - for example, XFS. Signed-off-by: Wu Fengguang Acked-by: Jan Kara Cc: Dave Chinner Cc: Christoph Hellwig Cc: Dave Chinner Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fs-writeback.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index fca43d4d7bf..1ce364bbb00 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -363,18 +363,7 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc) spin_lock(&inode_lock); inode->i_state &= ~I_SYNC; if (!(inode->i_state & I_FREEING)) { - if ((inode->i_state & I_DIRTY_PAGES) && wbc->for_kupdate) { - /* - * More pages get dirtied by a fast dirtier. - */ - goto select_queue; - } else if (inode->i_state & I_DIRTY) { - /* - * At least XFS will redirty the inode during the - * writeback (delalloc) and on io completion (isize). - */ - redirty_tail(inode); - } else if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) { + if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) { /* * We didn't write back all the pages. nfs_writepages() * sometimes bales out without doing anything. Redirty @@ -396,7 +385,6 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc) * soon as the queue becomes uncongested. */ inode->i_state |= I_DIRTY_PAGES; -select_queue: if (wbc->nr_to_write <= 0) { /* * slice used up: queue for next turn @@ -419,6 +407,14 @@ select_queue: inode->i_state |= I_DIRTY_PAGES; redirty_tail(inode); } + } else if (inode->i_state & I_DIRTY) { + /* + * Filesystems can dirty the inode during writeback + * operations, such as delayed allocation during + * submission or metadata updates after data IO + * completion. + */ + redirty_tail(inode); } else if (atomic_read(&inode->i_count)) { /* * The inode is clean, inuse -- 2.20.1