From e185dda89d69cde142b48059413a03561f41f78a Mon Sep 17 00:00:00 2001 From: Wu Fengguang Date: Sat, 23 Apr 2011 11:26:07 -0600 Subject: writeback: avoid extra sync work at enqueue time This removes writeback_control.wb_start and does more straightforward sync livelock prevention by setting .older_than_this to prevent extra inodes from being enqueued in the first place. Acked-by: Jan Kara Signed-off-by: Wu Fengguang --- fs/fs-writeback.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) (limited to 'fs') diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 565b1fd..d0553f3 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -544,15 +544,6 @@ static int writeback_sb_inodes(struct super_block *sb, struct bdi_writeback *wb, continue; } - /* - * Was this inode dirtied after sync_sb_inodes was called? - * This keeps sync from extra jobs and livelock. - */ - if (inode_dirtied_after(inode, wbc->wb_start)) { - spin_unlock(&inode->i_lock); - return 1; - } - __iget(inode); pages_skipped = wbc->pages_skipped; @@ -585,9 +576,6 @@ static void __writeback_inodes_wb(struct bdi_writeback *wb, { int ret = 0; - if (!wbc->wb_start) - wbc->wb_start = jiffies; /* livelock avoidance */ - while (!list_empty(&wb->b_io)) { struct inode *inode = wb_inode(wb->b_io.prev); struct super_block *sb = inode->i_sb; @@ -686,7 +674,9 @@ static long wb_writeback(struct bdi_writeback *wb, if (wbc.sync_mode == WB_SYNC_ALL || wbc.tagged_writepages) write_chunk = LONG_MAX; - wbc.wb_start = jiffies; /* livelock avoidance */ + oldest_jif = jiffies; + wbc.older_than_this = &oldest_jif; + spin_lock(&wb->list_lock); for (;;) { /* -- cgit v1.1