[PATCH v3 10/17] xfs: acquire ->ail_lock from xfs_trans_ail_delete()

[Brian Foster <bfoster@redhat.com>]

Several callers acquire the lock just prior to the call. Callers
that require ->ail_lock for other purposes already check IN_AIL
state and thus don't require the additional shutdown check in the
helper. Push the lock down into xfs_trans_ail_delete(), open code
the instances that still acquire it, and remove the unnecessary ailp
parameter.

Signed-off-by: Brian Foster <bfoster@redhat.com>
---
 fs/xfs/xfs_buf_item.c   | 27 +++++++++++----------------
 fs/xfs/xfs_dquot.c      |  6 ++++--
 fs/xfs/xfs_trans_ail.c  |  3 ++-
 fs/xfs/xfs_trans_priv.h | 14 ++++++++------
 4 files changed, 25 insertions(+), 25 deletions(-)

diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c
index 1f7acffc99ba..06e306b49283 100644
--- a/fs/xfs/xfs_buf_item.c
+++ b/fs/xfs/xfs_buf_item.c
@@ -410,7 +410,6 @@ xfs_buf_item_unpin(
 {
 	struct xfs_buf_log_item	*bip = BUF_ITEM(lip);
 	xfs_buf_t		*bp = bip->bli_buf;
-	struct xfs_ail		*ailp = lip->li_ailp;
 	int			stale = bip->bli_flags & XFS_BLI_STALE;
 	int			freed;
 
@@ -452,10 +451,10 @@ xfs_buf_item_unpin(
 		}
 
 		/*
-		 * If we get called here because of an IO error, we may
-		 * or may not have the item on the AIL. xfs_trans_ail_delete()
-		 * will take care of that situation.
-		 * xfs_trans_ail_delete() drops the AIL lock.
+		 * If we get called here because of an IO error, we may or may
+		 * not have the item on the AIL. xfs_trans_ail_delete() will
+		 * take care of that situation. xfs_trans_ail_delete() drops
+		 * the AIL lock.
 		 */
 		if (bip->bli_flags & XFS_BLI_STALE_INODE) {
 			xfs_buf_do_callbacks(bp);
@@ -463,8 +462,7 @@ xfs_buf_item_unpin(
 			list_del_init(&bp->b_li_list);
 			bp->b_iodone = NULL;
 		} else {
-			spin_lock(&ailp->ail_lock);
-			xfs_trans_ail_delete(ailp, lip, SHUTDOWN_LOG_IO_ERROR);
+			xfs_trans_ail_delete(lip, SHUTDOWN_LOG_IO_ERROR);
 			xfs_buf_item_relse(bp);
 			ASSERT(bp->b_log_item == NULL);
 		}
@@ -1205,22 +1203,19 @@ xfs_buf_iodone(
 	struct xfs_buf		*bp,
 	struct xfs_log_item	*lip)
 {
-	struct xfs_ail		*ailp = lip->li_ailp;
-
 	ASSERT(BUF_ITEM(lip)->bli_buf == bp);
 
 	xfs_buf_rele(bp);
 
 	/*
-	 * If we are forcibly shutting down, this may well be
-	 * off the AIL already. That's because we simulate the
-	 * log-committed callbacks to unpin these buffers. Or we may never
-	 * have put this item on AIL because of the transaction was
-	 * aborted forcibly. xfs_trans_ail_delete() takes care of these.
+	 * If we are forcibly shutting down, this may well be off the AIL
+	 * already. That's because we simulate the log-committed callbacks to
+	 * unpin these buffers. Or we may never have put this item on AIL
+	 * because of the transaction was aborted forcibly.
+	 * xfs_trans_ail_delete() takes care of these.
 	 *
 	 * Either way, AIL is useless if we're forcing a shutdown.
 	 */
-	spin_lock(&ailp->ail_lock);
-	xfs_trans_ail_delete(ailp, lip, SHUTDOWN_CORRUPT_INCORE);
+	xfs_trans_ail_delete(lip, SHUTDOWN_CORRUPT_INCORE);
 	xfs_buf_item_free(BUF_ITEM(lip));
 }
diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
index ffe607733c50..5fb65f43b980 100644
--- a/fs/xfs/xfs_dquot.c
+++ b/fs/xfs/xfs_dquot.c
@@ -1021,6 +1021,7 @@ xfs_qm_dqflush_done(
 	struct xfs_dq_logitem	*qip = (struct xfs_dq_logitem *)lip;
 	struct xfs_dquot	*dqp = qip->qli_dquot;
 	struct xfs_ail		*ailp = lip->li_ailp;
+	xfs_lsn_t		tail_lsn;
 
 	/*
 	 * We only want to pull the item from the AIL if its
@@ -1034,10 +1035,11 @@ xfs_qm_dqflush_done(
 	    ((lip->li_lsn == qip->qli_flush_lsn) ||
 	     test_bit(XFS_LI_FAILED, &lip->li_flags))) {
 
-		/* xfs_trans_ail_delete() drops the AIL lock. */
 		spin_lock(&ailp->ail_lock);
 		if (lip->li_lsn == qip->qli_flush_lsn) {
-			xfs_trans_ail_delete(ailp, lip, SHUTDOWN_CORRUPT_INCORE);
+			/* xfs_ail_update_finish() drops the AIL lock */
+			tail_lsn = xfs_ail_delete_one(ailp, lip);
+			xfs_ail_update_finish(ailp, tail_lsn);
 		} else {
 			/*
 			 * Clear the failed state since we are about to drop the
diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c
index 2574d01e4a83..cfba691664c7 100644
--- a/fs/xfs/xfs_trans_ail.c
+++ b/fs/xfs/xfs_trans_ail.c
@@ -864,13 +864,14 @@ xfs_ail_delete_one(
  */
 void
 xfs_trans_ail_delete(
-	struct xfs_ail		*ailp,
 	struct xfs_log_item	*lip,
 	int			shutdown_type)
 {
+	struct xfs_ail		*ailp = lip->li_ailp;
 	struct xfs_mount	*mp = ailp->ail_mount;
 	xfs_lsn_t		tail_lsn;
 
+	spin_lock(&ailp->ail_lock);
 	if (!test_bit(XFS_LI_IN_AIL, &lip->li_flags)) {
 		spin_unlock(&ailp->ail_lock);
 		if (!XFS_FORCED_SHUTDOWN(mp)) {
diff --git a/fs/xfs/xfs_trans_priv.h b/fs/xfs/xfs_trans_priv.h
index 35655eac01a6..e4362fb8d483 100644
--- a/fs/xfs/xfs_trans_priv.h
+++ b/fs/xfs/xfs_trans_priv.h
@@ -94,8 +94,7 @@ xfs_trans_ail_update(
 xfs_lsn_t xfs_ail_delete_one(struct xfs_ail *ailp, struct xfs_log_item *lip);
 void xfs_ail_update_finish(struct xfs_ail *ailp, xfs_lsn_t old_lsn)
 			__releases(ailp->ail_lock);
-void xfs_trans_ail_delete(struct xfs_ail *ailp, struct xfs_log_item *lip,
-		int shutdown_type);
+void xfs_trans_ail_delete(struct xfs_log_item *lip, int shutdown_type);
 
 static inline void
 xfs_trans_ail_remove(
@@ -103,13 +102,16 @@ xfs_trans_ail_remove(
 	int			shutdown_type)
 {
 	struct xfs_ail		*ailp = lip->li_ailp;
+	xfs_lsn_t		tail_lsn;
 
 	spin_lock(&ailp->ail_lock);
-	/* xfs_trans_ail_delete() drops the AIL lock */
-	if (test_bit(XFS_LI_IN_AIL, &lip->li_flags))
-		xfs_trans_ail_delete(ailp, lip, shutdown_type);
-	else
+	/* xfs_ail_update_finish() drops the AIL lock */
+	if (test_bit(XFS_LI_IN_AIL, &lip->li_flags)) {
+		tail_lsn = xfs_ail_delete_one(ailp, lip);
+		xfs_ail_update_finish(ailp, tail_lsn);
+	} else {
 		spin_unlock(&ailp->ail_lock);
+	}
 }
 
 void			xfs_ail_push(struct xfs_ail *, xfs_lsn_t);
-- 
2.21.1