ocfs2: track local alloc state via debugfs

A per-mount debugfs file, "local_alloc" is created which when read will
expose live state of the nodes local alloc file. Performance impact is
minimal, only a bit of memory overhead per mount point. Still, the code is
hidden behind CONFIG_OCFS2_FS_STATS. This feature will help us debug
local alloc performance problems on a live system.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index 4d6e200a4843..128279986d65 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -272,6 +272,11 @@ struct ocfs2_super
 
         u64 la_last_gd;
 
+#ifdef CONFIG_OCFS2_FS_STATS
+        struct dentry *local_alloc_debug;
+        char *local_alloc_debug_buf;
+#endif
+
         /* Next two fields are for local node slot recovery during
          * mount. */
         int dirty;