blk-sysfs: remove NULL pointer checking in queue_wb_lat_store

wbt_init doesn't set q->rq_wb to NULL, if wbt_init return 0,
so check return value is enough, remove NULL checking.

Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index e54be40..870484e 100644 (file)
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -450,12 +450,9 @@ static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page,
                ret = wbt_init(q);
                if (ret)
                        return ret;
-
-               rwb = q->rq_wb;
-               if (!rwb)
-                       return -EINVAL;
        }
 
+       rwb = q->rq_wb;
        if (val == -1)
                rwb->min_lat_nsec = wbt_default_latency_nsec(q);
        else if (val >= 0)