blk-mq: don't leak preempt counter/q_usage_counter when allocating rq failed (1ad43c00) · Commits · 戴 / test

block/blk-mq.c

+11 −6

Original line number	Diff line number	Diff line
		@@ -301,11 +301,12 @@ static struct request blk_mq_get_request(struct request_queue q,
		struct elevator_queue *e = q->elevator;
		struct request *rq;
		unsigned int tag;
		struct blk_mq_ctx *local_ctx = NULL;

		blk_queue_enter_live(q);
		data->q = q;
		if (likely(!data->ctx))
		data->ctx = blk_mq_get_ctx(q);
		data->ctx = local_ctx = blk_mq_get_ctx(q);
		if (likely(!data->hctx))
		data->hctx = blk_mq_map_queue(q, data->ctx->cpu);
		if (op & REQ_NOWAIT)
		@@ -324,6 +325,10 @@ static struct request blk_mq_get_request(struct request_queue q,

		tag = blk_mq_get_tag(data);
		if (tag == BLK_MQ_TAG_FAIL) {
		if (local_ctx) {
		blk_mq_put_ctx(local_ctx);
		data->ctx = NULL;
		}
		blk_queue_exit(q);
		return NULL;
		}
		@@ -356,12 +361,12 @@ struct request blk_mq_alloc_request(struct request_queue q, unsigned int op,

		rq = blk_mq_get_request(q, NULL, op, &alloc_data);

		blk_mq_put_ctx(alloc_data.ctx);
		blk_queue_exit(q);

		if (!rq)
		return ERR_PTR(-EWOULDBLOCK);

		blk_mq_put_ctx(alloc_data.ctx);
		blk_queue_exit(q);

		rq->__data_len = 0;
		rq->__sector = (sector_t) -1;
		rq->bio = rq->biotail = NULL;
		@@ -407,11 +412,11 @@ struct request blk_mq_alloc_request_hctx(struct request_queue q,

		rq = blk_mq_get_request(q, NULL, op, &alloc_data);

		blk_queue_exit(q);

		if (!rq)
		return ERR_PTR(-EWOULDBLOCK);

		blk_queue_exit(q);

		return rq;
		}
		EXPORT_SYMBOL_GPL(blk_mq_alloc_request_hctx);