When try to issue request directly, if the queue is stopped or
quiesced, 'bypass' will be ignored and return BLK_STS_OK to caller
to avoid it dispatch request again. Then the request will be
inserted with blk_mq_sched_insert_request. This is not correct
for dm-rq case where we should avoid to pass through the underlying
path's io scheduler.
To fix it, use blk_mq_request_bypass_insert to insert the request
to hctx->dispatch when we cannot pass through io scheduler but have
to insert.
Signed-off-by: Jianchao Wang <jianchao.w.wang@xxxxxxxxxx>
---
block/blk-mq.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 14b4d06..11c52bb 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1772,7 +1772,7 @@ static blk_status_t blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
bool bypass)
{
struct request_queue *q = rq->q;
- bool run_queue = true;
+ bool run_queue = true, force = false;
blk_status_t ret = BLK_STS_RESOURCE;
int srcu_idx;
@@ -1786,7 +1786,7 @@ static blk_status_t blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
*/
if (unlikely(blk_mq_hctx_stopped(hctx) || blk_queue_quiesced(q))) {
run_queue = false;
- bypass = false;
+ force = true;
goto out_unlock;
}
@@ -1817,6 +1817,9 @@ static blk_status_t blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
if (!bypass) {
blk_mq_sched_insert_request(rq, false, run_queue, false);
ret = BLK_STS_OK;
+ } else if (force) {
+ blk_mq_request_bypass_insert(rq, run_queue);
+ ret = BLK_STS_OK;
}
break;
default:
--
2.7.4
