@@ -441,6 +442,8 @@ static int blk_mq_sched_alloc_tags(struct request_queue *q,
if (!hctx->sched_tags)
return -ENOMEM;
+ set->sched_tags[hctx_idx] = hctx->sched_tags;
+
ret = blk_mq_alloc_rqs(set, hctx->sched_tags, hctx_idx, q->nr_requests);
if (ret)
blk_mq_sched_free_tags(set, hctx, hctx_idx);
Will this work as expected if a tag set is shared across multiple request queues?
Probably not.
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index c81b40e..c290de0 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -322,6 +322,22 @@ int blk_mq_tagset_iter(struct blk_mq_tag_set *set, void *data,
}
}
+ for (i = 0; i < set->nr_hw_queues; i++) {
+ struct blk_mq_tags *sched_tags = set->sched_tags[i];
+
+ if (!sched_tags)
+ continue;
+
+ for (j = 0; j < sched_tags->nr_tags; j++) {
+ if (!sched_tags->static_rqs[j])
+ continue;
+
+ ret = fn(data, sched_tags->static_rqs[j]);
+ if (ret)
+ goto out;
+ }
+ }
If both a scheduler tag and a driver tag have been assigned to a request, can this cause
blk_mq_tagset_iter() to call fn() twice for the same request?
It will, its not a big issue for reinit functionality, but it might if
used for something else. I don't think its a good idea to go down this
route.
