From d34849913819a5e0cbfbe724dbe79df89278c524 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 13 Jan 2017 14:43:58 -0700 Subject: blk-mq-sched: allow setting of default IO scheduler Add Kconfig entries to manage what devices get assigned an MQ scheduler, and add a blk-mq flag for drivers to opt out of scheduling. The latter is useful for admin type queues that still allocate a blk-mq queue and tag set, but aren't use for normal IO. Signed-off-by: Jens Axboe Reviewed-by: Bart Van Assche Reviewed-by: Omar Sandoval --- block/blk-mq-sched.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'block/blk-mq-sched.c') diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index 26759798a0b3..d05061f27bb1 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -366,3 +366,23 @@ void blk_mq_sched_teardown(struct request_queue *q) queue_for_each_hw_ctx(q, hctx, i) blk_mq_sched_free_tags(set, hctx, i); } + +int blk_mq_sched_init(struct request_queue *q) +{ + int ret; + +#if defined(CONFIG_DEFAULT_SQ_NONE) + if (q->nr_hw_queues == 1) + return 0; +#endif +#if defined(CONFIG_DEFAULT_MQ_NONE) + if (q->nr_hw_queues > 1) + return 0; +#endif + + mutex_lock(&q->sysfs_lock); + ret = elevator_init(q, NULL); + mutex_unlock(&q->sysfs_lock); + + return ret; +} -- cgit