bfq: ignore oom_bfqq in bfq_check_waker

oom_bfqq is just a fallback bfqq, so shouldn't be used with waker
detection.
Suggested-by: NJan Kara <jack@suse.cz>
Signed-off-by: NKhazhismel Kumykov <khazhy@google.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221108181030.1611703-2-khazhy@google.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

block/bfq-iosched.c

@@ -2083,7 +2083,9 @@ static void bfq_check_waker(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 	if (!bfqd->last_completed_rq_bfqq ||
 	    bfqd->last_completed_rq_bfqq == bfqq ||
 	    bfq_bfqq_has_short_ttime(bfqq) ||
-	    now_ns - bfqd->last_completion >= 4 * NSEC_PER_MSEC)
+	    now_ns - bfqd->last_completion >= 4 * NSEC_PER_MSEC ||
+	    bfqd->last_completed_rq_bfqq == &bfqd->oom_bfqq ||
+	    bfqq == &bfqd->oom_bfqq)
 		return;
 
 	/*