From b86dd815ff74ab9eda474d1c28428ac0db2c3032 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 22 Feb 2017 13:19:45 -0700 Subject: block: get rid of blk-mq default scheduler choice Kconfig entries The wording in the entries were poor and not understandable by even deities. Kill the selection for default block scheduler, and impose a policy with sane defaults. Architected-by: Linus Torvalds Reviewed-by: Omar Sandoval Signed-off-by: Jens Axboe --- block/elevator.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) (limited to 'block/elevator.c') diff --git a/block/elevator.c b/block/elevator.c index 699d10f71a2c..ac1c9f481a98 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -220,17 +220,24 @@ int elevator_init(struct request_queue *q, char *name) } if (!e) { - if (q->mq_ops && q->nr_hw_queues == 1) - e = elevator_get(CONFIG_DEFAULT_SQ_IOSCHED, false); - else if (q->mq_ops) - e = elevator_get(CONFIG_DEFAULT_MQ_IOSCHED, false); - else + /* + * For blk-mq devices, we default to using mq-deadline, + * if available, for single queue devices. If deadline + * isn't available OR we have multiple queues, default + * to "none". + */ + if (q->mq_ops) { + if (q->nr_hw_queues == 1) + e = elevator_get("mq-deadline", false); + if (!e) + return 0; + } else e = elevator_get(CONFIG_DEFAULT_IOSCHED, false); if (!e) { printk(KERN_ERR "Default I/O scheduler not found. " \ - "Using noop/none.\n"); + "Using noop.\n"); e = elevator_get("noop", false); } } -- cgit v1.2.3