From 414dd48e882c5a39e7bd01b096ee6497eb3314b0 Mon Sep 17 00:00:00 2001 From: Chao Leng Date: Tue, 1 Nov 2022 16:00:49 +0100 Subject: [PATCH] blk-mq: add tagset quiesce interface Drivers that have shared tagsets may need to quiesce potentially a lot of request queues that all share a single tagset (e.g. nvme). Add an interface to quiesce all the queues on a given tagset. This interface is useful because it can speedup the quiesce by doing it in parallel. Because some queues should not need to be quiesced (e.g. the nvme connect_q) when quiescing the tagset, introduce a QUEUE_FLAG_SKIP_TAGSET_QUIESCE flag to allow this new interface to ski quiescing a particular queue. Signed-off-by: Chao Leng [hch: simplify for the per-tag_set srcu_struct] Signed-off-by: Christoph Hellwig Reviewed-by: Keith Busch Reviewed-by: Sagi Grimberg Reviewed-by: Ming Lei Reviewed-by: Chao Leng Reviewed-by: Hannes Reinecke Reviewed-by: Chaitanya Kulkarni Link: https://lore.kernel.org/r/20221101150050.3510-14-hch@lst.de Signed-off-by: Jens Axboe --- block/blk-mq.c | 27 +++++++++++++++++++++++++++ include/linux/blk-mq.h | 2 ++ include/linux/blkdev.h | 3 +++ 3 files changed, 32 insertions(+) diff --git a/block/blk-mq.c b/block/blk-mq.c index b7abfda..bae6f81 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -315,6 +315,33 @@ void blk_mq_unquiesce_queue(struct request_queue *q) } EXPORT_SYMBOL_GPL(blk_mq_unquiesce_queue); +void blk_mq_quiesce_tagset(struct blk_mq_tag_set *set) +{ + struct request_queue *q; + + mutex_lock(&set->tag_list_lock); + list_for_each_entry(q, &set->tag_list, tag_set_list) { + if (!blk_queue_skip_tagset_quiesce(q)) + blk_mq_quiesce_queue_nowait(q); + } + blk_mq_wait_quiesce_done(set); + mutex_unlock(&set->tag_list_lock); +} +EXPORT_SYMBOL_GPL(blk_mq_quiesce_tagset); + +void blk_mq_unquiesce_tagset(struct blk_mq_tag_set *set) +{ + struct request_queue *q; + + mutex_lock(&set->tag_list_lock); + list_for_each_entry(q, &set->tag_list, tag_set_list) { + if (!blk_queue_skip_tagset_quiesce(q)) + blk_mq_unquiesce_queue(q); + } + mutex_unlock(&set->tag_list_lock); +} +EXPORT_SYMBOL_GPL(blk_mq_unquiesce_tagset); + void blk_mq_wake_waiters(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 061ea6e..109a0e3 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -881,6 +881,8 @@ void blk_mq_start_stopped_hw_queue(struct blk_mq_hw_ctx *hctx, bool async); void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async); void blk_mq_quiesce_queue(struct request_queue *q); void blk_mq_wait_quiesce_done(struct blk_mq_tag_set *set); +void blk_mq_quiesce_tagset(struct blk_mq_tag_set *set); +void blk_mq_unquiesce_tagset(struct blk_mq_tag_set *set); void blk_mq_unquiesce_queue(struct request_queue *q); void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs); void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 6a6fa16..9188aa3 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -571,6 +571,7 @@ struct request_queue { #define QUEUE_FLAG_HCTX_ACTIVE 28 /* at least one blk-mq hctx is active */ #define QUEUE_FLAG_NOWAIT 29 /* device supports NOWAIT */ #define QUEUE_FLAG_SQ_SCHED 30 /* single queue style io dispatch */ +#define QUEUE_FLAG_SKIP_TAGSET_QUIESCE 31 /* quiesce_tagset skip the queue*/ #define QUEUE_FLAG_MQ_DEFAULT ((1UL << QUEUE_FLAG_IO_STAT) | \ (1UL << QUEUE_FLAG_SAME_COMP) | \ @@ -610,6 +611,8 @@ bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q); #define blk_queue_pm_only(q) atomic_read(&(q)->pm_only) #define blk_queue_registered(q) test_bit(QUEUE_FLAG_REGISTERED, &(q)->queue_flags) #define blk_queue_sq_sched(q) test_bit(QUEUE_FLAG_SQ_SCHED, &(q)->queue_flags) +#define blk_queue_skip_tagset_quiesce(q) \ + test_bit(QUEUE_FLAG_SKIP_TAGSET_QUIESCE, &(q)->queue_flags) extern void blk_set_pm_only(struct request_queue *q); extern void blk_clear_pm_only(struct request_queue *q); -- 2.7.4