1 files changed, 52 insertions, 0 deletions

diff --git a/fs/xfs/libxfs/xfs_defer.c b/fs/xfs/libxfs/xfs_defer.c
index 8d42b914dcd4..5e5806d0b161 100644
--- a/fs/xfs/libxfs/xfs_defer.c
+++ b/fs/xfs/libxfs/xfs_defer.c
@@ -17,6 +17,7 @@
 #include "xfs_inode_item.h"
 #include "xfs_trace.h"
 #include "xfs_icache.h"
+#include "xfs_log.h"
 
 /*
  * Deferred Operations in XFS
@@ -346,6 +347,52 @@ xfs_defer_cancel_list(
 }
 
 /*
+ * Prevent a log intent item from pinning the tail of the log by logging a
+ * done item to release the intent item; and then log a new intent item.
+ * The caller should provide a fresh transaction and roll it after we're done.
+ */
+static int
+xfs_defer_relog(
+	struct xfs_trans		**tpp,
+	struct list_head		*dfops)
+{
+	struct xfs_defer_pending	*dfp;
+	xfs_lsn_t			threshold_lsn;
+
+	ASSERT((*tpp)->t_flags & XFS_TRANS_PERM_LOG_RES);
+
+	/*
+	 * Figure out where we need the tail to be in order to maintain the
+	 * minimum required free space in the log.
+	 */
+	threshold_lsn = xlog_grant_push_threshold((*tpp)->t_mountp->m_log, 0);
+	if (threshold_lsn == NULLCOMMITLSN)
+		return 0;
+
+	list_for_each_entry(dfp, dfops, dfp_list) {
+		/*
+		 * If the log intent item for this deferred op is behind the
+		 * desired log tail threshold and is not a part of the current
+		 * log checkpoint, relog the intent item to keep the log tail
+		 * moving forward.  We're ok with this being racy because an
+		 * incorrect decision means we'll be a little slower at pushing
+		 * the tail.
+		 */
+		if (dfp->dfp_intent == NULL ||
+		    XFS_LSN_CMP(dfp->dfp_intent->li_lsn, threshold_lsn) >= 0 ||
+		    xfs_log_item_in_current_chkpt(dfp->dfp_intent))
+			continue;
+
+		trace_xfs_defer_relog_intent((*tpp)->t_mountp, dfp);
+		dfp->dfp_intent = xfs_trans_item_relog(dfp->dfp_intent, *tpp);
+	}
+
+	if ((*tpp)->t_flags & XFS_TRANS_DIRTY)
+		return xfs_defer_trans_roll(tpp);
+	return 0;
+}
+
+/*
  * Log an intent-done item for the first pending intent, and finish the work
  * items.
  */
@@ -431,6 +478,11 @@ xfs_defer_finish_noroll(
 		if (error)
 			goto out_shutdown;
 
+		/* Possibly relog intent items to keep the log moving. */
+		error = xfs_defer_relog(tp, &dop_pending);
+		if (error)
+			goto out_shutdown;
+
 		dfp = list_first_entry(&dop_pending, struct xfs_defer_pending,
 				       dfp_list);
 		error = xfs_defer_finish_one(*tp, dfp);