The function blk_queue_stopped() allows to test whether or not a non-mq queue has been stopped. Introduce a helper function that allows block drivers to query easily whether or not one or more hardware contexts of a blk-mq queue have been stopped.
Signed-off-by: Bart Van Assche <[email protected]> Cc: Jens Axboe <[email protected]> Cc: Christoph Hellwig <[email protected]> --- block/blk-mq.c | 17 +++++++++++++++++ include/linux/blk-mq.h | 1 + 2 files changed, 18 insertions(+) diff --git a/block/blk-mq.c b/block/blk-mq.c index 0dcafa6..6929a52 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -965,6 +965,23 @@ void blk_mq_run_hw_queues(struct request_queue *q, bool async) } EXPORT_SYMBOL(blk_mq_run_hw_queues); +/* + * The caller is responsible for serializing this function against + * blk_mq_{start,stop}_hw_queue(). + */ +bool blk_mq_queue_stopped(struct request_queue *q) +{ + struct blk_mq_hw_ctx *hctx; + int i; + + queue_for_each_hw_ctx(q, hctx, i) + if (test_bit(BLK_MQ_S_STOPPED, &hctx->state)) + return true; + + return false; +} +EXPORT_SYMBOL(blk_mq_queue_stopped); + void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) { cancel_delayed_work(&hctx->run_work); diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index e43bbff..bd677bc 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -235,6 +235,7 @@ void blk_mq_kick_requeue_list(struct request_queue *q); void blk_mq_abort_requeue_list(struct request_queue *q); void blk_mq_complete_request(struct request *rq, int error); +bool blk_mq_queue_stopped(struct request_queue *q); void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx); void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx); void blk_mq_stop_hw_queues(struct request_queue *q); -- 2.9.3 -- dm-devel mailing list [email protected] https://www.redhat.com/mailman/listinfo/dm-devel
