blk-mq: issue directly with bypass 'false' in blk_mq_sched_insert_requests

It is not necessary to issue request directly with bypass 'true'
in blk_mq_sched_insert_requests and handle the non-issued requests
itself. Just set bypass to 'false' and let blk_mq_try_issue_directly
handle them totally. Remove the blk_rq_can_direct_dispatch check,
because blk_mq_try_issue_directly can handle it well.If request is
direct-issued unsuccessfully, insert the reset.

Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

2 files changed, 12 insertions, 16 deletions

diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
index f096d8989773..5b4d52d9cba2 100644
--- a/block/blk-mq-sched.c
+++ b/block/blk-mq-sched.c
@@ -417,12 +417,10 @@ void blk_mq_sched_insert_requests(struct blk_mq_hw_ctx *hctx,
                  * busy in case of 'none' scheduler, and this way may save
                  * us one extra enqueue & dequeue to sw queue.
                  */
-                if (!hctx->dispatch_busy && !e && !run_queue_async) {
+                if (!hctx->dispatch_busy && !e && !run_queue_async)
                         blk_mq_try_issue_list_directly(hctx, list);
-                        if (list_empty(list))
-                                return;
-                }
-                blk_mq_insert_requests(hctx, ctx, list);
+                else
+                        blk_mq_insert_requests(hctx, ctx, list);
         }
 
         blk_mq_run_hw_queue(hctx, run_queue_async);
diff --git a/block/blk-mq.c b/block/blk-mq.c
index af4dc8227954..90361fe758f8 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1874,22 +1874,20 @@ blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last)
 void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
                 struct list_head *list)
 {
+        blk_qc_t unused;
+        blk_status_t ret = BLK_STS_OK;
+
         while (!list_empty(list)) {
-                blk_status_t ret;
                 struct request *rq = list_first_entry(list, struct request,
                                 queuelist);
 
                 list_del_init(&rq->queuelist);
-                ret = blk_mq_request_issue_directly(rq, list_empty(list));
-                if (ret != BLK_STS_OK) {
-                        if (ret == BLK_STS_RESOURCE ||
-                                        ret == BLK_STS_DEV_RESOURCE) {
-                                blk_mq_request_bypass_insert(rq,
+                if (ret == BLK_STS_OK)
+                        ret = blk_mq_try_issue_directly(hctx, rq, &unused,
+                                                        false,
                                                         list_empty(list));
-                                break;
-                        }
-                        blk_mq_end_request(rq, ret);
-                }
+                else
+                        blk_mq_sched_insert_request(rq, false, true, false);
         }
 
         /*
@@ -1897,7 +1895,7 @@ void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
          * the driver there was more coming, but that turned out to
          * be a lie.
          */
-        if (!list_empty(list) && hctx->queue->mq_ops->commit_rqs)
+        if (ret != BLK_STS_OK && hctx->queue->mq_ops->commit_rqs)
                 hctx->queue->mq_ops->commit_rqs(hctx);
 }