ext4: add new trace event in ext4_fc_cleanup

This adds a new trace event in ext4_fc_cleanup() which is helpful in debugging
some fast_commit issues.

Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/794cdb1d5d3622f3f80d30c222ff6652ea68c375.1647057583.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c
index 6990429..f4a5629 100644 (file)
--- a/fs/ext4/fast_commit.c
+++ b/fs/ext4/fast_commit.c
@@ -1280,6 +1280,7 @@ 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 3d48fcb..20654aa 100644 (file)
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -2863,6 +2863,32 @@ TRACE_EVENT(ext4_fc_track_range,
                      __entry->end)
        );
 
+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),