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Diffstat (limited to 'block/blk-mq.c')
-rw-r--r--block/blk-mq.c47
1 files changed, 30 insertions, 17 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 159e69bd2c3c..22db728dbe24 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1695,7 +1695,7 @@ static int blk_mq_init_hctx(struct request_queue *q,
INIT_LIST_HEAD(&hctx->dispatch);
hctx->queue = q;
hctx->queue_num = hctx_idx;
- hctx->flags = set->flags;
+ hctx->flags = set->flags & ~BLK_MQ_F_TAG_SHARED;
blk_mq_init_cpu_notifier(&hctx->cpu_notifier,
blk_mq_hctx_notify, hctx);
@@ -1882,27 +1882,26 @@ static void blk_mq_map_swqueue(struct request_queue *q,
}
}
-static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set)
+static void queue_set_hctx_shared(struct request_queue *q, bool shared)
{
struct blk_mq_hw_ctx *hctx;
- struct request_queue *q;
- bool shared;
int i;
- if (set->tag_list.next == set->tag_list.prev)
- shared = false;
- else
- shared = true;
+ queue_for_each_hw_ctx(q, hctx, i) {
+ if (shared)
+ hctx->flags |= BLK_MQ_F_TAG_SHARED;
+ else
+ hctx->flags &= ~BLK_MQ_F_TAG_SHARED;
+ }
+}
+
+static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set, bool shared)
+{
+ struct request_queue *q;
list_for_each_entry(q, &set->tag_list, tag_set_list) {
blk_mq_freeze_queue(q);
-
- queue_for_each_hw_ctx(q, hctx, i) {
- if (shared)
- hctx->flags |= BLK_MQ_F_TAG_SHARED;
- else
- hctx->flags &= ~BLK_MQ_F_TAG_SHARED;
- }
+ queue_set_hctx_shared(q, shared);
blk_mq_unfreeze_queue(q);
}
}
@@ -1913,7 +1912,12 @@ static void blk_mq_del_queue_tag_set(struct request_queue *q)
mutex_lock(&set->tag_list_lock);
list_del_init(&q->tag_set_list);
- blk_mq_update_tag_set_depth(set);
+ if (list_is_singular(&set->tag_list)) {
+ /* just transitioned to unshared */
+ set->flags &= ~BLK_MQ_F_TAG_SHARED;
+ /* update existing queue */
+ blk_mq_update_tag_set_depth(set, false);
+ }
mutex_unlock(&set->tag_list_lock);
}
@@ -1923,8 +1927,17 @@ static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set,
q->tag_set = set;
mutex_lock(&set->tag_list_lock);
+
+ /* Check to see if we're transitioning to shared (from 1 to 2 queues). */
+ if (!list_empty(&set->tag_list) && !(set->flags & BLK_MQ_F_TAG_SHARED)) {
+ set->flags |= BLK_MQ_F_TAG_SHARED;
+ /* update existing queue */
+ blk_mq_update_tag_set_depth(set, true);
+ }
+ if (set->flags & BLK_MQ_F_TAG_SHARED)
+ queue_set_hctx_shared(q, true);
list_add_tail(&q->tag_set_list, &set->tag_list);
- blk_mq_update_tag_set_depth(set);
+
mutex_unlock(&set->tag_list_lock);
}