[RFC 3/9] ext4: Add couple of more fast_commit tracepoints

[Ritesh Harjani <riteshh@xxxxxxxxxxxxx>]

This adds two more tracepoints for ext4_fc_track_template() &
ext4_fc_cleanup() which are helpful in debugging some fast_commit issues.

Signed-off-by: Ritesh Harjani <riteshh@xxxxxxxxxxxxx>
---
 fs/ext4/fast_commit.c       |  3 ++
 include/trace/events/ext4.h | 67 +++++++++++++++++++++++++++++++++++++
 2 files changed, 70 insertions(+)

diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c
index 5ac594e03402..bf70879bb4fe 100644
--- a/fs/ext4/fast_commit.c
+++ b/fs/ext4/fast_commit.c
@@ -386,6 +386,8 @@ static int ext4_fc_track_template(
 	if (ext4_test_mount_flag(inode->i_sb, EXT4_MF_FC_INELIGIBLE))
 		return -EINVAL;
 
+	trace_ext4_fc_track_template(handle, inode, __fc_track_fn, enqueue);
+
 	tid = handle->h_transaction->t_tid;
 	mutex_lock(&ei->i_fc_lock);
 	if (tid == ei->i_sync_tid) {
@@ -1241,6 +1243,7 @@ static void ext4_fc_cleanup(journal_t *journal, int full, tid_t tid)
 	if (full && sbi->s_fc_bh)
 		sbi->s_fc_bh = NULL;
 
+	trace_ext4_fc_cleanup(journal, full, tid);
 	jbd2_fc_release_bufs(journal);
 
 	spin_lock(&sbi->s_fc_lock);
diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
index 17fb9c506e8a..cd09dccea502 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -2855,6 +2855,73 @@ TRACE_EVENT(ext4_fc_track_range,
 		      __entry->end)
 	);
 
+TRACE_EVENT(ext4_fc_track_template,
+	TP_PROTO(handle_t *handle, struct inode *inode,
+		 void *__fc_track_fn, int enqueue),
+
+	TP_ARGS(handle, inode, __fc_track_fn, enqueue),
+
+	TP_STRUCT__entry(
+		__field(dev_t, dev)
+		__field(tid_t, t_tid)
+		__field(ino_t, i_ino)
+		__field(tid_t, i_sync_tid)
+		__field(void *, __fc_track_fn)
+		__field(int, enqueue)
+		__field(bool, jbd2_ongoing)
+		__field(bool, fc_ongoing)
+	),
+
+	TP_fast_assign(
+		struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+		struct ext4_inode_info *ei = EXT4_I(inode);
+
+		__entry->dev = inode->i_sb->s_dev;
+		__entry->t_tid = handle->h_transaction->t_tid;
+		__entry->i_ino = inode->i_ino;
+		__entry->i_sync_tid = ei->i_sync_tid;
+		__entry->__fc_track_fn = __fc_track_fn;
+		__entry->enqueue = enqueue;
+		__entry->jbd2_ongoing =
+		    sbi->s_journal->j_flags & JBD2_FULL_COMMIT_ONGOING;
+		__entry->fc_ongoing =
+		    sbi->s_journal->j_flags & JBD2_FAST_COMMIT_ONGOING;
+	),
+
+	TP_printk("dev %d,%d, t_tid %u, ino %lu, i_sync_tid %u, "
+		  "track_fn %pS, enqueue %d, jbd2_ongoing %d, fc_ongoing %d",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  __entry->t_tid, __entry->i_ino, __entry->i_sync_tid,
+		  (void *)__entry->__fc_track_fn, __entry->enqueue,
+		  __entry->jbd2_ongoing, __entry->fc_ongoing)
+	);
+
+TRACE_EVENT(ext4_fc_cleanup,
+	TP_PROTO(journal_t *journal, int full, tid_t tid),
+
+	TP_ARGS(journal, full, tid),
+
+	TP_STRUCT__entry(
+		__field(dev_t, dev)
+		__field(int, j_fc_off)
+		__field(int, full)
+		__field(tid_t, tid)
+	),
+
+	TP_fast_assign(
+		struct super_block *sb = journal->j_private;
+
+		__entry->dev = sb->s_dev;
+		__entry->j_fc_off = journal->j_fc_off;
+		__entry->full = full;
+		__entry->tid = tid;
+	),
+
+	TP_printk("dev %d,%d, j_fc_off %d, full %d, tid %u",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  __entry->j_fc_off, __entry->full, __entry->tid)
+	);
+
 TRACE_EVENT(ext4_update_sb,
 	TP_PROTO(struct super_block *sb, ext4_fsblk_t fsblk,
 		 unsigned int flags),
-- 
2.31.1