[RFC v6 PATCH 01/10] xfs: automatic relogging item management

[Brian Foster <bfoster@redhat.com>]

Add a log item flag to track relog state and a couple helpers to set
and clear the flag. The flag will be set on any log item that is to
be automatically relogged by log tail pressure.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
---
 fs/xfs/xfs_trace.h      |  2 ++
 fs/xfs/xfs_trans.c      | 20 ++++++++++++++++++++
 fs/xfs/xfs_trans.h      |  4 +++-
 fs/xfs/xfs_trans_priv.h |  2 ++
 4 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index a4323a63438d..b683c94556a3 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -1068,6 +1068,8 @@ DEFINE_LOG_ITEM_EVENT(xfs_ail_push);
 DEFINE_LOG_ITEM_EVENT(xfs_ail_pinned);
 DEFINE_LOG_ITEM_EVENT(xfs_ail_locked);
 DEFINE_LOG_ITEM_EVENT(xfs_ail_flushing);
+DEFINE_LOG_ITEM_EVENT(xfs_relog_item);
+DEFINE_LOG_ITEM_EVENT(xfs_relog_item_cancel);
 
 DECLARE_EVENT_CLASS(xfs_ail_class,
 	TP_PROTO(struct xfs_log_item *lip, xfs_lsn_t old_lsn, xfs_lsn_t new_lsn),
diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
index 28b983ff8b11..4fbe11485bbb 100644
--- a/fs/xfs/xfs_trans.c
+++ b/fs/xfs/xfs_trans.c
@@ -770,6 +770,26 @@ xfs_trans_del_item(
 	list_del_init(&lip->li_trans);
 }
 
+void
+xfs_trans_relog_item(
+	struct xfs_trans	*tp,
+	struct xfs_log_item	*lip)
+{
+	if (test_and_set_bit(XFS_LI_RELOG, &lip->li_flags))
+		return;
+	trace_xfs_relog_item(lip);
+}
+
+void
+xfs_trans_relog_item_cancel(
+	struct xfs_trans	*tp,
+	struct xfs_log_item	*lip)
+{
+	if (!test_and_clear_bit(XFS_LI_RELOG, &lip->li_flags))
+		return;
+	trace_xfs_relog_item_cancel(lip);
+}
+
 /* Detach and unlock all of the items in a transaction */
 static void
 xfs_trans_free_items(
diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index 752c7fef9de7..9ea0f415e5ca 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -59,12 +59,14 @@ struct xfs_log_item {
 #define	XFS_LI_ABORTED	1
 #define	XFS_LI_FAILED	2
 #define	XFS_LI_DIRTY	3	/* log item dirty in transaction */
+#define	XFS_LI_RELOG	4	/* automatically relog item */
 
 #define XFS_LI_FLAGS \
 	{ (1 << XFS_LI_IN_AIL),		"IN_AIL" }, \
 	{ (1 << XFS_LI_ABORTED),	"ABORTED" }, \
 	{ (1 << XFS_LI_FAILED),		"FAILED" }, \
-	{ (1 << XFS_LI_DIRTY),		"DIRTY" }
+	{ (1 << XFS_LI_DIRTY),		"DIRTY" }, \
+	{ (1 << XFS_LI_RELOG),		"RELOG" }
 
 struct xfs_item_ops {
 	unsigned flags;
diff --git a/fs/xfs/xfs_trans_priv.h b/fs/xfs/xfs_trans_priv.h
index 35655eac01a6..c890794314a6 100644
--- a/fs/xfs/xfs_trans_priv.h
+++ b/fs/xfs/xfs_trans_priv.h
@@ -16,6 +16,8 @@ struct xfs_log_vec;
 void	xfs_trans_init(struct xfs_mount *);
 void	xfs_trans_add_item(struct xfs_trans *, struct xfs_log_item *);
 void	xfs_trans_del_item(struct xfs_log_item *);
+void	xfs_trans_relog_item(struct xfs_trans *, struct xfs_log_item *);
+void	xfs_trans_relog_item_cancel(struct xfs_trans *, struct xfs_log_item *);
 void	xfs_trans_unreserve_and_mod_sb(struct xfs_trans *tp);
 
 void	xfs_trans_committed_bulk(struct xfs_ail *ailp, struct xfs_log_vec *lv,
-- 
2.21.1