[PATCH v2] nvme: change order of qid and cmdid in completion trace

[PATCH v2] nvme: change order of qid and cmdid in completion trace

[Johannes Thumshirn]

Keith reported that command submission and command completion
tracepoints have the order of the cmdid and qid fields swapped.

While it isn't easily possible to change the command submission
tracepoint, as there is a regression test parsing it in blktests we
can swap the command completion tracepoint to have the fields aligned.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reported-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>

---
* Changes to v1:
- Changed two typos Jens spotted
- Add Jens' R-b
---
 drivers/nvme/host/trace.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/nvme/host/trace.h b/drivers/nvme/host/trace.h
index ea91fccd1bc0..01390f0e1671 100644
--- a/drivers/nvme/host/trace.h
+++ b/drivers/nvme/host/trace.h
@@ -148,8 +148,8 @@ TRACE_EVENT(nvme_complete_rq,
 		    __entry->flags = nvme_req(req)->flags;
 		    __entry->status = nvme_req(req)->status;
 	    ),
-	    TP_printk("cmdid=%u, qid=%d, res=%llu, retries=%u, flags=0x%x, status=%u",
-		      __entry->cid, __entry->qid, __entry->result,
+	    TP_printk("qid=%d, cmdid=%u, res=%llu, retries=%u, flags=0x%x, status=%u",
+		      __entry->qid, __entry->cid, __entry->result,
 		      __entry->retries, __entry->flags, __entry->status)
 
 );
-- 
2.16.3

Re: [PATCH v2] nvme: change order of qid and cmdid in completion trace

[Keith Busch]

On Thu, Apr 26, 2018 at 02:25:15PM -0600, Johannes Thumshirn wrote:
> Keith reported that command submission and command completion
> tracepoints have the order of the cmdid and qid fields swapped.
> 
> While it isn't easily possible to change the command submission
> tracepoint, as there is a regression test parsing it in blktests we
> can swap the command completion tracepoint to have the fields aligned.

It's the little things that matter. :)

Thanks, applied to nvme-4.18.

Re: [PATCH v2] nvme: change order of qid and cmdid in completion trace

[Christoph Hellwig]

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>