jbd2: add tracepoints which provide per-handle statistics

Handles which stay open a long time are problematic when it comes time
to close down a transaction so it can be committed.  These tracepoints
will help us determine which ones are the problematic ones, and to
validate whether changes makes things better or worse.

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

1 files changed, 7 insertions, 1 deletions

diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 24db7256a5ff..fa5fea17b619 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -400,6 +400,11 @@ struct jbd2_journal_handle
         unsigned int    h_sync:         1;      /* sync-on-close */
         unsigned int    h_jdata:        1;      /* force data journaling */
         unsigned int    h_aborted:      1;      /* fatal error on handle */
+        unsigned int    h_type:         8;      /* for handle statistics */
+        unsigned int    h_line_no:      16;     /* for handle statistics */
+
+        unsigned long           h_start_jiffies;
+        unsigned int            h_requested_credits;
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
         struct lockdep_map      h_lockdep_map;
@@ -1071,7 +1076,8 @@ static inline handle_t *journal_current_handle(void)
  */
 
 extern handle_t *jbd2_journal_start(journal_t *, int nblocks);
-extern handle_t *jbd2__journal_start(journal_t *, int nblocks, gfp_t gfp_mask);
+extern handle_t *jbd2__journal_start(journal_t *, int nblocks, gfp_t gfp_mask,
+                                     unsigned int type, unsigned int line_no);
 extern int       jbd2_journal_restart(handle_t *, int nblocks);
 extern int       jbd2__journal_restart(handle_t *, int nblocks, gfp_t gfp_mask);
 extern int       jbd2_journal_extend (handle_t *, int nblocks);