From fd00144301d64f1742541a3c5e64cd1c51f39c55 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Fri, 28 Oct 2016 17:19:37 -0700 Subject: [PATCH] blk-mq: Introduce blk_mq_queue_stopped() The function blk_queue_stopped() allows to test whether or not a traditional request 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 Reviewed-by: Hannes Reinecke Reviewed-by: Johannes Thumshirn Reviewed-by: Sagi Grimberg Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-mq.c | 20 ++++++++++++++++++++ include/linux/blk-mq.h | 1 + 2 files changed, 21 insertions(+) diff --git a/block/blk-mq.c b/block/blk-mq.c index 2864e191cc86..28bf667bfe09 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -944,6 +944,26 @@ void blk_mq_run_hw_queues(struct request_queue *q, bool async) } EXPORT_SYMBOL(blk_mq_run_hw_queues); +/** + * blk_mq_queue_stopped() - check whether one or more hctxs have been stopped + * @q: request queue. + * + * 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 (blk_mq_hctx_stopped(hctx)) + return true; + + return false; +} +EXPORT_SYMBOL(blk_mq_queue_stopped); + void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) { cancel_work(&hctx->run_work); diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 535ab2e13d2e..aa930009fcd3 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -223,6 +223,7 @@ void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs 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); -- 2.20.1