From: Yu Kuai yukuai3@huawei.com
commit 285febabac4a16655372d23ff43e89ff6f216691 upstream.
commit 8c5035dfbb94 ("blk-wbt: call rq_qos_add() after wb_normal is initialized") moves wbt_set_write_cache() before rq_qos_add(), which is wrong because wbt_rq_qos() is still NULL.
Fix the problem by removing wbt_set_write_cache() and setting 'rwb->wc' directly. Noted that this patch also remove the redundant setting of 'rab->wc'.
Fixes: 8c5035dfbb94 ("blk-wbt: call rq_qos_add() after wb_normal is initialized") Reported-by: kernel test robot yujie.liu@intel.com Link: https://lore.kernel.org/r/202210081045.77ddf59b-yujie.liu@intel.com Signed-off-by: Yu Kuai yukuai3@huawei.com Reviewed-by: Ming Lei ming.lei@redhat.com Link: https://lore.kernel.org/r/20221009101038.1692875-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- block/blk-wbt.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
--- a/block/blk-wbt.c +++ b/block/blk-wbt.c @@ -841,12 +841,11 @@ int wbt_init(struct request_queue *q) rwb->last_comp = rwb->last_issue = jiffies; rwb->win_nsec = RWB_WINDOW_NSEC; rwb->enable_state = WBT_STATE_ON_DEFAULT; - rwb->wc = 1; + rwb->wc = test_bit(QUEUE_FLAG_WC, &q->queue_flags); rwb->rq_depth.default_depth = RWB_DEF_DEPTH; rwb->min_lat_nsec = wbt_default_latency_nsec(q);
wbt_queue_depth_changed(&rwb->rqos); - wbt_set_write_cache(q, test_bit(QUEUE_FLAG_WC, &q->queue_flags));
/* * Assign rwb and add the stats callback.