cfq-iosched: removing unnecessary think time checking
[linux-2.6.git] / block / cfq-iosched.c
index fea1b5a..7785169 100644 (file)
@@ -2417,19 +2417,14 @@ static bool cfq_may_dispatch(struct cfq_data *cfqd, struct cfq_queue *cfqq)
                        return false;
 
                /*
-                * If there is only one sync queue, and its think time is
-                * small, we can ignore async queue here and give the sync
+                * If there is only one sync queue
+                * we can ignore async queue here and give the sync
                 * queue no dispatch limit. The reason is a sync queue can
                 * preempt async queue, limiting the sync queue doesn't make
                 * sense. This is useful for aiostress test.
                 */
-               if (cfq_cfqq_sync(cfqq) && cfqd->busy_sync_queues == 1) {
-                       struct cfq_io_context *cic = RQ_CIC(cfqq->next_rq);
-
-                       if (sample_valid(cic->ttime_samples) &&
-                               cic->ttime_mean < cfqd->cfq_slice_idle)
-                               promote_sync = true;
-               }
+               if (cfq_cfqq_sync(cfqq) && cfqd->busy_sync_queues == 1)
+                       promote_sync = true;
 
                /*
                 * We have other queues, don't allow more IO from this one