Re: [PATCH v4 2/2] trace nvme submit queue status

hch
2018-12-18T17:47:53Z

On Tue, Dec 18, 2018 at 10:26:46AM -0700, Keith Busch wrote:
> No need for a space after the %s. __print_disk_name already appends a
> space if there's a disk name, and we don't want the extra space if there
> isn't one. Also, every other nvme trace has a ',' after each entry. Not
> a big deal, just minor format consistency.

Yeah. What about something like this incremental patch to make the
trace formatting and argument passing match what we otherwise do:

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 2477bd906904..5a0bf6a24d50 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1004,8 +1004,7 @@ static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx)
}

req = blk_mq_tag_to_rq(*nvmeq->tags, cqe->command_id);
- trace_nvme_sq(req->rq_disk, nvmeq->qid, le16_to_cpu(cqe->sq_head),
- nvmeq->sq_tail);
+ trace_nvme_sq(req, cqe->sq_head, nvmeq->sq_tail);
nvme_end_request(req, cqe->status, cqe->result);
}

diff --git a/drivers/nvme/host/trace.h b/drivers/nvme/host/trace.h
index cf666709bc50..3564120aa7b3 100644
--- a/drivers/nvme/host/trace.h
+++ b/drivers/nvme/host/trace.h
@@ -185,22 +185,24 @@ TRACE_EVENT(nvme_async_event,
#undef aer_name

TRACE_EVENT(nvme_sq,
- TP_PROTO(void *rq_disk, int qid, int sq_head, int sq_tail),
- TP_ARGS(rq_disk, qid, sq_head, sq_tail),
+ TP_PROTO(struct request *req, __le16 sq_head, int sq_tail),
+ TP_ARGS(req, sq_head, sq_tail),
TP_STRUCT__entry(
+ __field(int, ctrl_id)
__array(char, disk, DISK_NAME_LEN)
__field(int, qid)
- __field(int, sq_head)
- __field(int, sq_tail)
+ __field(u16, sq_head)
+ __field(u16, sq_tail)
),
TP_fast_assign(
- __assign_disk_name(__entry->disk, rq_disk);
- __entry->qid = qid;
- __entry->sq_head = sq_head;
+ __entry->ctrl_id = nvme_req(req)->ctrl->instance;
+ __assign_disk_name(__entry->disk, req->rq_disk);
+ __entry->qid = nvme_req_qid(req);
+ __entry->sq_head = le16_to_cpu(sq_head);
__entry->sq_tail = sq_tail;
),
- TP_printk("nvme: %s qid=%d head=%d tail=%d",
- __print_disk_name(__entry->disk),
+ TP_printk("nvme%d: %sqid=%d, head=%u, tail=%u",
+ __entry->ctrl_id, __print_disk_name(__entry->disk),
__entry->qid, __entry->sq_head, __entry->sq_tail
)
);