ext4: add tracepoint for ext4_journal_start

This will help debug who is responsible for starting a jbd2 transaction.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 9ea71aa864b3..7910e61809e7 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -269,6 +269,7 @@ handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
         journal_t *journal;
         handle_t  *handle;
 
+        trace_ext4_journal_start(sb, nblocks, _RET_IP_);
         if (sb->s_flags & MS_RDONLY)
                 return ERR_PTR(-EROFS);