From 671fae5e51297fc76b3758ca2edd514858734a6a Mon Sep 17 00:00:00 2001 From: Yu Kuai Date: Wed, 19 Oct 2022 20:15:18 +0800 Subject: blk-wbt: don't enable throttling if default elevator is bfq Commit b5dc5d4d1f4f ("block,bfq: Disable writeback throttling") tries to disable wbt for bfq, it's done by calling wbt_disable_default() in bfq_init_queue(). However, wbt is still enabled if default elevator is bfq: device_add_disk elevator_init_mq bfq_init_queue wbt_disable_default -> done nothing blk_register_queue wbt_enable_default -> wbt is enabled Fix the problem by adding a new flag ELEVATOR_FLAG_DISBALE_WBT, bfq will set the flag in bfq_init_queue, and following wbt_enable_default() won't enable wbt while the flag is set. Signed-off-by: Yu Kuai Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20221019121518.3865235-7-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe --- block/bfq-iosched.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'block/bfq-iosched.c') diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index 7ea427817f7f..ccfadc6f71bf 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -7045,6 +7045,7 @@ static void bfq_exit_queue(struct elevator_queue *e) #endif blk_stat_disable_accounting(bfqd->queue); + clear_bit(ELEVATOR_FLAG_DISABLE_WBT, &e->flags); wbt_enable_default(bfqd->queue); kfree(bfqd); @@ -7190,6 +7191,7 @@ static int bfq_init_queue(struct request_queue *q, struct elevator_type *e) /* We dispatch from request queue wide instead of hw queue */ blk_queue_flag_set(QUEUE_FLAG_SQ_SCHED, q); + set_bit(ELEVATOR_FLAG_DISABLE_WBT, &eq->flags); wbt_disable_default(q); blk_stat_enable_accounting(q); -- cgit v1.2.3