On 12/20/18 6:02 AM, Jens Axboe wrote:
>> I'm afraid this cannot work.
>>
>> The 'tags' here could be the hctx->sched_tags, but what we need to
>> clear is hctx->tags->rqs[].
>
> You are right, of course, a bit too quick on the trigger. This one
> should work better, and also avoids that silly quadratic loop. I don't
> think we need the tag == -1 check, but probably best to be safe.
Sent out the wrong one, here it is. Bart, if you can reproduce, can you
give it a whirl?
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 2de972857496..fc04bb648f18 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2025,7 +2025,7 @@ void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
{
struct page *page;
- if (tags->rqs && set->ops->exit_request) {
+ if (tags->rqs) {
int i;
for (i = 0; i < tags->nr_tags; i++) {
@@ -2033,8 +2033,14 @@ void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
if (!rq)
continue;
- set->ops->exit_request(set, rq, hctx_idx);
+ if (set->ops->exit_request)
+ set->ops->exit_request(set, rq, hctx_idx);
tags->static_rqs[i] = NULL;
+
+ if (rq->tag == -1)
+ continue;
+ if (set->tags[hctx_idx]->rqs[rq->tag] == rq)
+ set->tags[hctx_idx]->rqs[rq->tag] = NULL;
}
}
@@ -2113,6 +2119,7 @@ static int blk_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
return ret;
}
+ rq->tag = -1;
WRITE_ONCE(rq->state, MQ_RQ_IDLE);
return 0;
}
--
Jens Axboe
