From: Ed Tsai <ed.tsai@xxxxxxxxxxxx>
Refer to
commit f168420c62e7
("blk-mq: don't redirect completion for hctx withs only one ctx mapping")
When nvme applies a 1:1 mapping of hctx and ctx, there will be no remote
request.
But for ufs, the submission and completion queue could be asymmetric.
(e.g. Multiple SQs share one CQ) Therefore, 1:1 mapping of hctx and
ctx won't complete request on the submission cpu. In this situation,
put this condition in block layer could violate the
QUEUE_FLAG_SAME_FORCE, as a result, move this back to nvme.
Signed-off-by: Ed Tsai <ed.tsai@xxxxxxxxxxxx>
Signed-off-by: Po-Wen Kao <powen.kao@xxxxxxxxxxxx>
---
block/blk-mq.c | 8 +++-----
drivers/nvme/host/nvme.h | 4 ++++
2 files changed, 7 insertions(+), 5 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 1749f5890606..b60c78f5ad46 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1181,12 +1181,10 @@ bool blk_mq_complete_request_remote(struct request *rq)
WRITE_ONCE(rq->state, MQ_RQ_COMPLETE);
/*
- * For request which hctx has only one ctx mapping,
- * or a polled request, always complete locally,
- * it's pointless to redirect the completion.
+ * For a polled request, always complete locally, it's pointless
+ * to redirect the completion.
*/
- if (rq->mq_hctx->nr_ctx == 1 ||
- rq->cmd_flags & REQ_POLLED)
+ if (rq->cmd_flags & REQ_POLLED)
return false;
if (blk_mq_complete_need_ipi(rq)) {
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 7cf8e44d135e..acc9b1ce071d 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -702,6 +702,10 @@ static inline bool nvme_try_complete_req(struct request *req, __le16 status,
nvme_should_fail(req);
if (unlikely(blk_should_fake_timeout(req->q)))
return true;
+ if (likely(req->mq_hctx->nr_ctx == 1)) {
+ WRITE_ONCE(req->state, MQ_RQ_COMPLETE);
+ return false;
+ }
return blk_mq_complete_request_remote(req);
}
--
2.18.0
