diff options
| author | Shaohua Li <shli@fb.com> | 2016-11-18 09:44:08 -0800 |
|---|---|---|
| committer | Shaohua Li <shli@fb.com> | 2016-11-18 09:47:57 -0800 |
| commit | 504634f60f463e73e7d58c6810a04437da942dba (patch) | |
| tree | abdc28fb557c2158f005a6f271c60c983562c43e /drivers/md | |
| parent | 578b54ade8a5e04df6edc14cb68ad0f6f491a1a1 (diff) | |
md: add blktrace event for writes to superblock
superblock write is an expensive operation. With raid5-cache, it can be called
regularly. Tracing to help performance debug.
Signed-off-by: Shaohua Li <shli@fb.com>
Cc: NeilBrown <neilb@suse.com>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/md.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index 1f1c7f007b68..d3cef771e422 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -64,6 +64,7 @@ #include <linux/raid/md_p.h> #include <linux/raid/md_u.h> #include <linux/slab.h> +#include <trace/events/block.h> #include "md.h" #include "bitmap.h" #include "md-cluster.h" @@ -2403,6 +2404,8 @@ repeat: pr_debug("md: updating %s RAID superblock on device (in sync %d)\n", mdname(mddev), mddev->in_sync); + if (mddev->queue) + blk_add_trace_msg(mddev->queue, "md md_update_sb"); bitmap_update_sb(mddev->bitmap); rdev_for_each(rdev, mddev) { char b[BDEVNAME_SIZE]; |