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@@ -2863,3 +2863,86 @@ static bool cfq_may_dispatch(struct cfq_data *cfqd, struct cfq_queue *cfqq)
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*/
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if (!cfq_cfqq_sync(cfqq) && cfqd->cfq_latency) {
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unsigned long last_sync = jiffies - cfqd->last_delayed_sync;
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+ unsigned int depth;
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+
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+ depth = last_sync / cfqd->cfq_slice[1];
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+ if (!depth && !cfqq->dispatched)
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+ depth = 1;
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+ if (depth < max_dispatch)
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+ max_dispatch = depth;
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+ }
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+
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+ /*
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+ * If we're below the current max, allow a dispatch
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+ */
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+ return cfqq->dispatched < max_dispatch;
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+}
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+
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+/*
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+ * Dispatch a request from cfqq, moving them to the request queue
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+ * dispatch list.
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+ */
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+static bool cfq_dispatch_request(struct cfq_data *cfqd, struct cfq_queue *cfqq)
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+{
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+ struct request *rq;
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+
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+ BUG_ON(RB_EMPTY_ROOT(&cfqq->sort_list));
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+
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+ if (!cfq_may_dispatch(cfqd, cfqq))
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+ return false;
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+
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+ /*
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+ * follow expired path, else get first next available
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+ */
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+ rq = cfq_check_fifo(cfqq);
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+ if (!rq)
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+ rq = cfqq->next_rq;
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+
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+ /*
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+ * insert request into driver dispatch list
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+ */
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+ cfq_dispatch_insert(cfqd->queue, rq);
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+
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+ if (!cfqd->active_cic) {
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+ struct cfq_io_cq *cic = RQ_CIC(rq);
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+
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+ atomic_long_inc(&cic->icq.ioc->refcount);
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+ cfqd->active_cic = cic;
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+ }
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+
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+ return true;
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+}
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+
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+/*
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+ * Find the cfqq that we need to service and move a request from that to the
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+ * dispatch list
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+ */
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+static int cfq_dispatch_requests(struct request_queue *q, int force)
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+{
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+ struct cfq_data *cfqd = q->elevator->elevator_data;
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+ struct cfq_queue *cfqq;
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+
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+ if (!cfqd->busy_queues)
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+ return 0;
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+
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+ if (unlikely(force))
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+ return cfq_forced_dispatch(cfqd);
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+
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+ cfqq = cfq_select_queue(cfqd);
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+ if (!cfqq)
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+ return 0;
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+
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+ /*
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+ * Dispatch a request from this cfqq, if it is allowed
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+ */
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+ if (!cfq_dispatch_request(cfqd, cfqq))
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+ return 0;
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+
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+ cfqq->slice_dispatch++;
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+ cfq_clear_cfqq_must_dispatch(cfqq);
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+
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+ /*
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+ * expire an async queue immediately if it has used up its slice. idle
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+ * queue always expire after 1 dispatch round.
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+ */
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+ if (cfqd->busy_queues > 1 && ((!cfq_cfqq_sync(cfqq) &&
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