From: Yu Kuai <yukuai3@xxxxxxxxxx> commit b11d31ae01e6 ("blk-wbt: remove unnecessary check in wbt_enable_default()") removes the checking of CONFIG_BLK_WBT_MQ by mistake, which is used to control enable or disable wbt by default. Fix the problem by adding back the checking. This patch also do a litter cleanup to make related code more readable. Fixes: b11d31ae01e6 ("blk-wbt: remove unnecessary check in wbt_enable_default()") Reported-by: Lukas Bulwahn <lukas.bulwahn@xxxxxxxxx> Link: https://lore.kernel.org/lkml/CAKXUXMzfKq_J9nKHGyr5P5rvUETY4B-fxoQD4sO+NYjFOfVtZA@xxxxxxxxxxxxxx/t/ Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx> --- block/blk-wbt.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/block/blk-wbt.c b/block/blk-wbt.c index e49a48684532..9ec2a2f1eda3 100644 --- a/block/blk-wbt.c +++ b/block/blk-wbt.c @@ -730,14 +730,16 @@ void wbt_enable_default(struct gendisk *disk) { struct request_queue *q = disk->queue; struct rq_qos *rqos; - bool disable_flag = q->elevator && - test_bit(ELEVATOR_FLAG_DISABLE_WBT, &q->elevator->flags); + bool enable = IS_ENABLED(CONFIG_BLK_WBT_MQ); + + if (q->elevator && + test_bit(ELEVATOR_FLAG_DISABLE_WBT, &q->elevator->flags)) + enable = false; /* Throttling already enabled? */ rqos = wbt_rq_qos(q); if (rqos) { - if (!disable_flag && - RQWB(rqos)->enable_state == WBT_STATE_OFF_DEFAULT) + if (enable && RQWB(rqos)->enable_state == WBT_STATE_OFF_DEFAULT) RQWB(rqos)->enable_state = WBT_STATE_ON_DEFAULT; return; } @@ -746,7 +748,7 @@ void wbt_enable_default(struct gendisk *disk) if (!blk_queue_registered(q)) return; - if (queue_is_mq(q) && !disable_flag) + if (queue_is_mq(q) && enable) wbt_init(disk); } EXPORT_SYMBOL_GPL(wbt_enable_default); -- 2.39.2