blk-mq: Move more code into blk_mq_direct_issue_request()

Move the "hctx stopped" test and the insert request calls into
blk_mq_direct_issue_request(). Rename that function into
blk_mq_try_issue_directly() to reflect its new semantics. Pass
the hctx pointer to that function instead of looking it up a
second time. These changes avoid that code has to be duplicated
in the next patch.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 28bf667..447c37f 100644 (file)
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1228,11 +1228,11 @@ static struct request *blk_mq_map_request(struct request_queue *q,
        return rq;
 }
 
-static int blk_mq_direct_issue_request(struct request *rq, blk_qc_t *cookie)
+static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
+                                     struct request *rq, blk_qc_t *cookie)
 {
        int ret;
        struct request_queue *q = rq->q;
-       struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, rq->mq_ctx->cpu);
        struct blk_mq_queue_data bd = {
                .rq = rq,
                .list = NULL,
@@ -1240,6 +1240,9 @@ static int blk_mq_direct_issue_request(struct request *rq, blk_qc_t *cookie)
        };
        blk_qc_t new_cookie = blk_tag_to_qc_t(rq->tag, hctx->queue_num);
 
+       if (blk_mq_hctx_stopped(hctx))
+               goto insert;
+
        /*
         * For OK queue, we are done. For error, kill it. Any other
         * error (busy), just add it to our list as we previously
@@ -1248,7 +1251,7 @@ static int blk_mq_direct_issue_request(struct request *rq, blk_qc_t *cookie)
        ret = q->mq_ops->queue_rq(hctx, &bd);
        if (ret == BLK_MQ_RQ_QUEUE_OK) {
                *cookie = new_cookie;
-               return 0;
+               return;
        }
 
        __blk_mq_requeue_request(rq);
@@ -1257,10 +1260,11 @@ static int blk_mq_direct_issue_request(struct request *rq, blk_qc_t *cookie)
                *cookie = BLK_QC_T_NONE;
                rq->errors = -EIO;
                blk_mq_end_request(rq, rq->errors);
-               return 0;
+               return;
        }
 
-       return -1;
+insert:
+       blk_mq_insert_request(rq, false, true, true);
 }
 
 /*
@@ -1337,9 +1341,7 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
                blk_mq_put_ctx(data.ctx);
                if (!old_rq)
                        goto done;
-               if (blk_mq_hctx_stopped(data.hctx) ||
-                   blk_mq_direct_issue_request(old_rq, &cookie) != 0)
-                       blk_mq_insert_request(old_rq, false, true, true);
+               blk_mq_try_issue_directly(data.hctx, old_rq, &cookie);
                goto done;
        }