From 453eac8a9aa417878a38bdfbccafd5f7ce4e8e4e Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Mon, 11 Jan 2010 11:49:58 +0000 Subject: [PATCH] xfs: Don't wake the aild once per second Now that the AIL push algorithm is traversal safe, we don't need a watchdog function in the xfsaild to catch pushes that fail to make progress. Remove the watchdog timeout and make pushes purely driven by demand. This will remove the once-per-second wakeup that is seen when the filesystem is idle and make laptop power misers happy. Signed-off-by: Dave Chinner Reviewed-by: Christoph Hellwig Signed-off-by: Alex Elder --- fs/xfs/linux-2.6/xfs_super.c | 7 +++---- fs/xfs/xfs_trans_ail.c | 19 +++++++++++-------- 2 files changed, 14 insertions(+), 12 deletions(-) diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c index 77414db10dc2..9f2e398a5616 100644 --- a/fs/xfs/linux-2.6/xfs_super.c +++ b/fs/xfs/linux-2.6/xfs_super.c @@ -877,12 +877,11 @@ xfsaild( { struct xfs_ail *ailp = data; xfs_lsn_t last_pushed_lsn = 0; - long tout = 0; + long tout = 0; /* milliseconds */ while (!kthread_should_stop()) { - if (tout) - schedule_timeout_interruptible(msecs_to_jiffies(tout)); - tout = 1000; + schedule_timeout_interruptible(tout ? + msecs_to_jiffies(tout) : MAX_SCHEDULE_TIMEOUT); /* swsusp */ try_to_freeze(); diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c index 2ffc570679be..063dfbdca94b 100644 --- a/fs/xfs/xfs_trans_ail.c +++ b/fs/xfs/xfs_trans_ail.c @@ -237,14 +237,15 @@ xfs_trans_ail_cursor_first( } /* - * Function that does the work of pushing on the AIL + * xfsaild_push does the work of pushing on the AIL. Returning a timeout of + * zero indicates that the caller should sleep until woken. */ long xfsaild_push( struct xfs_ail *ailp, xfs_lsn_t *last_lsn) { - long tout = 1000; /* milliseconds */ + long tout = 0; xfs_lsn_t last_pushed_lsn = *last_lsn; xfs_lsn_t target = ailp->xa_target; xfs_lsn_t lsn; @@ -262,7 +263,7 @@ xfsaild_push( */ xfs_trans_ail_cursor_done(ailp, cur); spin_unlock(&ailp->xa_lock); - last_pushed_lsn = 0; + *last_lsn = 0; return tout; } @@ -279,7 +280,6 @@ xfsaild_push( * prevents use from spinning when we can't do anything or there is * lots of contention on the AIL lists. */ - tout = 10; lsn = lip->li_lsn; flush_log = stuck = count = 0; while ((XFS_LSN_CMP(lip->li_lsn, target) < 0)) { @@ -376,14 +376,14 @@ xfsaild_push( if (!count) { /* We're past our target or empty, so idle */ - tout = 1000; + last_pushed_lsn = 0; } else if (XFS_LSN_CMP(lsn, target) >= 0) { /* * We reached the target so wait a bit longer for I/O to * complete and remove pushed items from the AIL before we * start the next scan from the start of the AIL. */ - tout += 20; + tout = 50; last_pushed_lsn = 0; } else if ((stuck * 100) / count > 90) { /* @@ -395,11 +395,14 @@ xfsaild_push( * Backoff a bit more to allow some I/O to complete before * continuing from where we were. */ - tout += 10; + tout = 20; + } else { + /* more to do, but wait a short while before continuing */ + tout = 10; } *last_lsn = last_pushed_lsn; return tout; -} /* xfsaild_push */ +} /*