| Message ID | 20200812081844.22224-1-lengchao@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | improve nvme retry mechanism | expand |
On Wed, Aug 12, 2020 at 04:18:44PM +0800, Chao Leng wrote: > nvme should not depend on blk status, just need check nvme status. > Just need do translating nvme status to blk status for returning error. While this doesn't look wrong it also doesn't save us a single instruction and actually adds more lines of code. Do you have a good reason for this change?
On Wed, Aug 12 2020 at 11:10am -0400, Christoph Hellwig <hch@lst.de> wrote: > On Wed, Aug 12, 2020 at 04:18:44PM +0800, Chao Leng wrote: > > nvme should not depend on blk status, just need check nvme status. > > Just need do translating nvme status to blk status for returning error. > > While this doesn't look wrong it also doesn't save us a single > instruction and actually adds more lines of code. Do you have a good > reason for this change? It certainly saves nvme_error_status(nvme_req(req)->status if nvme_req_needs_retry().
On 2020/8/12 23:10, Christoph Hellwig wrote: > On Wed, Aug 12, 2020 at 04:18:44PM +0800, Chao Leng wrote: >> nvme should not depend on blk status, just need check nvme status. >> Just need do translating nvme status to blk status for returning error. > > While this doesn't look wrong it also doesn't save us a single > instruction and actually adds more lines of code. Do you have a good > reason for this change? If need retry, save nvme_error_status. Of course, it doesn't matter. There's no logical change, just want nvme do not care blk status when check retry. It is ok to change or not.
On Wed, Aug 12, 2020 at 04:28:30PM -0400, Mike Snitzer wrote: > On Wed, Aug 12 2020 at 11:10am -0400, > Christoph Hellwig <hch@lst.de> wrote: > > > On Wed, Aug 12, 2020 at 04:18:44PM +0800, Chao Leng wrote: > > > nvme should not depend on blk status, just need check nvme status. > > > Just need do translating nvme status to blk status for returning error. > > > > While this doesn't look wrong it also doesn't save us a single > > instruction and actually adds more lines of code. Do you have a good > > reason for this change? > > It certainly saves nvme_error_status(nvme_req(req)->status if > nvme_req_needs_retry(). Yeah, but the retry path isn't exactly the fast path, is it? Not that I really care too much about this one..
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 52d19a4d3bc8..246988091c05 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -278,7 +278,7 @@ static void nvme_retry_req(struct request *req) void nvme_complete_rq(struct request *req) { - blk_status_t status = nvme_error_status(nvme_req(req)->status); + blk_status_t status; trace_nvme_complete_rq(req); @@ -287,7 +287,8 @@ void nvme_complete_rq(struct request *req) if (nvme_req(req)->ctrl->kas) nvme_req(req)->ctrl->comp_seen = true; - if (unlikely(status != BLK_STS_OK && nvme_req_needs_retry(req))) { + if (unlikely(nvme_req(req)->status != NVME_SC_SUCCESS && + nvme_req_needs_retry(req))) { if (nvme_req_path_error(req)) { if (req->cmd_flags & REQ_NVME_MPATH) { nvme_failover_req(req); @@ -299,6 +300,7 @@ void nvme_complete_rq(struct request *req) } } + status = nvme_error_status(nvme_req(req)->status); nvme_trace_bio_complete(req, status); blk_mq_end_request(req, status); }
nvme should not depend on blk status, just need check nvme status. Just need do translating nvme status to blk status for returning error. Signed-off-by: Chao Leng <lengchao@huawei.com> --- drivers/nvme/host/core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)