1 files changed, 62 insertions, 42 deletions

diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c
index 812108f6cc89..a41ba155d3a3 100644
--- a/fs/xfs/xfs_trans_ail.c
+++ b/fs/xfs/xfs_trans_ail.c
@@ -108,17 +108,25 @@ xfs_ail_next(
  * We need the AIL lock in order to get a coherent read of the lsn of the last
  * item in the AIL.
  */
+static xfs_lsn_t
+__xfs_ail_min_lsn(
+	struct xfs_ail		*ailp)
+{
+	struct xfs_log_item	*lip = xfs_ail_min(ailp);
+
+	if (lip)
+		return lip->li_lsn;
+	return 0;
+}
+
 xfs_lsn_t
 xfs_ail_min_lsn(
 	struct xfs_ail		*ailp)
 {
-	xfs_lsn_t		lsn = 0;
-	struct xfs_log_item	*lip;
+	xfs_lsn_t		lsn;
 
 	spin_lock(&ailp->ail_lock);
-	lip = xfs_ail_min(ailp);
-	if (lip)
-		lsn = lip->li_lsn;
+	lsn = __xfs_ail_min_lsn(ailp);
 	spin_unlock(&ailp->ail_lock);
 
 	return lsn;
@@ -394,16 +402,10 @@ xfsaild_push(
 	target = ailp->ail_target;
 	ailp->ail_target_prev = target;
 
+	/* we're done if the AIL is empty or our push has reached the end */
 	lip = xfs_trans_ail_cursor_first(ailp, &cur, ailp->ail_last_pushed_lsn);
-	if (!lip) {
-		/*
-		 * If the AIL is empty or our push has reached the end we are
-		 * done now.
-		 */
-		xfs_trans_ail_cursor_done(&cur);
-		spin_unlock(&ailp->ail_lock);
+	if (!lip)
 		goto out_done;
-	}
 
 	XFS_STATS_INC(mp, xs_push_ail);
 
@@ -485,6 +487,8 @@ xfsaild_push(
 			break;
 		lsn = lip->li_lsn;
 	}
+
+out_done:
 	xfs_trans_ail_cursor_done(&cur);
 	spin_unlock(&ailp->ail_lock);
 
@@ -492,7 +496,6 @@ xfsaild_push(
 		ailp->ail_log_flush++;
 
 	if (!count || XFS_LSN_CMP(lsn, target) >= 0) {
-out_done:
 		/*
 		 * We reached the target or the AIL is empty, so wait a bit
 		 * longer for I/O to complete and remove pushed items from the
@@ -584,7 +587,8 @@ xfsaild(
 		 */
 		smp_rmb();
 		if (!xfs_ail_min(ailp) &&
-		    ailp->ail_target == ailp->ail_target_prev) {
+		    ailp->ail_target == ailp->ail_target_prev &&
+		    list_empty(&ailp->ail_buf_list)) {
 			spin_unlock(&ailp->ail_lock);
 			freezable_schedule();
 			tout = 0;
@@ -680,6 +684,28 @@ xfs_ail_push_all_sync(
 	finish_wait(&ailp->ail_empty, &wait);
 }
 
+void
+xfs_ail_update_finish(
+	struct xfs_ail		*ailp,
+	xfs_lsn_t		old_lsn) __releases(ailp->ail_lock)
+{
+	struct xfs_mount	*mp = ailp->ail_mount;
+
+	/* if the tail lsn hasn't changed, don't do updates or wakeups. */
+	if (!old_lsn || old_lsn == __xfs_ail_min_lsn(ailp)) {
+		spin_unlock(&ailp->ail_lock);
+		return;
+	}
+
+	if (!XFS_FORCED_SHUTDOWN(mp))
+		xlog_assign_tail_lsn_locked(mp);
+
+	if (list_empty(&ailp->ail_head))
+		wake_up_all(&ailp->ail_empty);
+	spin_unlock(&ailp->ail_lock);
+	xfs_log_space_wake(mp);
+}
+
 /*
  * xfs_trans_ail_update - bulk AIL insertion operation.
  *
@@ -711,7 +737,7 @@ xfs_trans_ail_update_bulk(
 	xfs_lsn_t		lsn) __releases(ailp->ail_lock)
 {
 	struct xfs_log_item	*mlip;
-	int			mlip_changed = 0;
+	xfs_lsn_t		tail_lsn = 0;
 	int			i;
 	LIST_HEAD(tmp);
 
@@ -726,9 +752,10 @@ xfs_trans_ail_update_bulk(
 				continue;
 
 			trace_xfs_ail_move(lip, lip->li_lsn, lsn);
+			if (mlip == lip && !tail_lsn)
+				tail_lsn = lip->li_lsn;
+
 			xfs_ail_delete(ailp, lip);
-			if (mlip == lip)
-				mlip_changed = 1;
 		} else {
 			trace_xfs_ail_insert(lip, 0, lsn);
 		}
@@ -739,23 +766,23 @@ xfs_trans_ail_update_bulk(
 	if (!list_empty(&tmp))
 		xfs_ail_splice(ailp, cur, &tmp, lsn);
 
-	if (mlip_changed) {
-		if (!XFS_FORCED_SHUTDOWN(ailp->ail_mount))
-			xlog_assign_tail_lsn_locked(ailp->ail_mount);
-		spin_unlock(&ailp->ail_lock);
-
-		xfs_log_space_wake(ailp->ail_mount);
-	} else {
-		spin_unlock(&ailp->ail_lock);
-	}
+	xfs_ail_update_finish(ailp, tail_lsn);
 }
 
-bool
+/*
+ * Delete one log item from the AIL.
+ *
+ * If this item was at the tail of the AIL, return the LSN of the log item so
+ * that we can use it to check if the LSN of the tail of the log has moved
+ * when finishing up the AIL delete process in xfs_ail_update_finish().
+ */
+xfs_lsn_t
 xfs_ail_delete_one(
 	struct xfs_ail		*ailp,
 	struct xfs_log_item	*lip)
 {
 	struct xfs_log_item	*mlip = xfs_ail_min(ailp);
+	xfs_lsn_t		lsn = lip->li_lsn;
 
 	trace_xfs_ail_delete(lip, mlip->li_lsn, lip->li_lsn);
 	xfs_ail_delete(ailp, lip);
@@ -763,7 +790,9 @@ xfs_ail_delete_one(
 	clear_bit(XFS_LI_IN_AIL, &lip->li_flags);
 	lip->li_lsn = 0;
 
-	return mlip == lip;
+	if (mlip == lip)
+		return lsn;
+	return 0;
 }
 
 /**
@@ -791,10 +820,10 @@ void
 xfs_trans_ail_delete(
 	struct xfs_ail		*ailp,
 	struct xfs_log_item	*lip,
-	int			shutdown_type) __releases(ailp->ail_lock)
+	int			shutdown_type)
 {
 	struct xfs_mount	*mp = ailp->ail_mount;
-	bool			mlip_changed;
+	xfs_lsn_t		tail_lsn;
 
 	if (!test_bit(XFS_LI_IN_AIL, &lip->li_flags)) {
 		spin_unlock(&ailp->ail_lock);
@@ -807,17 +836,8 @@ xfs_trans_ail_delete(
 		return;
 	}
 
-	mlip_changed = xfs_ail_delete_one(ailp, lip);
-	if (mlip_changed) {
-		if (!XFS_FORCED_SHUTDOWN(mp))
-			xlog_assign_tail_lsn_locked(mp);
-		if (list_empty(&ailp->ail_head))
-			wake_up_all(&ailp->ail_empty);
-	}
-
-	spin_unlock(&ailp->ail_lock);
-	if (mlip_changed)
-		xfs_log_space_wake(ailp->ail_mount);
+	tail_lsn = xfs_ail_delete_one(ailp, lip);
+	xfs_ail_update_finish(ailp, tail_lsn);
 }
 
 int