xfs: exit AIL push work correctly when AIL is empty
The recent conversion of the xfsaild functionality to a work queue
introduced a hard-to-hit log space grant hang. The main cause is a
regression where a work exit path fails to clear the PUSHING state
and recheck the target correctly.
Make both exit paths do the same PUSHING bit clearing and target
checking when the "no more work to be done" condition is hit.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
(cherry picked from commit ea35a20021f8497390d05b93271b4d675516c654)
diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c
index acdb92f..226c58b 100644
--- a/fs/xfs/xfs_trans_ail.c
+++ b/fs/xfs/xfs_trans_ail.c
@@ -346,18 +346,20 @@
*/
STATIC void
xfs_ail_worker(
- struct work_struct *work)
+ struct work_struct *work)
{
- struct xfs_ail *ailp = container_of(to_delayed_work(work),
+ struct xfs_ail *ailp = container_of(to_delayed_work(work),
struct xfs_ail, xa_work);
- long tout;
- xfs_lsn_t target = ailp->xa_target;
- xfs_lsn_t lsn;
- xfs_log_item_t *lip;
- int flush_log, count, stuck;
- xfs_mount_t *mp = ailp->xa_mount;
+ xfs_mount_t *mp = ailp->xa_mount;
struct xfs_ail_cursor *cur = &ailp->xa_cursors;
- int push_xfsbufd = 0;
+ xfs_log_item_t *lip;
+ xfs_lsn_t lsn;
+ xfs_lsn_t target = ailp->xa_target;
+ long tout = 10;
+ int flush_log = 0;
+ int stuck = 0;
+ int count = 0;
+ int push_xfsbufd = 0;
spin_lock(&ailp->xa_lock);
xfs_trans_ail_cursor_init(ailp, cur);
@@ -368,8 +370,7 @@
*/
xfs_trans_ail_cursor_done(ailp, cur);
spin_unlock(&ailp->xa_lock);
- ailp->xa_last_pushed_lsn = 0;
- return;
+ goto out_done;
}
XFS_STATS_INC(xs_push_ail);
@@ -386,7 +387,6 @@
* lots of contention on the AIL lists.
*/
lsn = lip->li_lsn;
- flush_log = stuck = count = 0;
while ((XFS_LSN_CMP(lip->li_lsn, target) < 0)) {
int lock_result;
/*
@@ -480,7 +480,7 @@
}
/* assume we have more work to do in a short while */
- tout = 10;
+out_done:
if (!count) {
/* We're past our target or empty, so idle */
ailp->xa_last_pushed_lsn = 0;