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@@ -2452,3 +2452,106 @@ static int cfqq_process_refs(struct cfq_queue *cfqq)
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return process_refs;
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return process_refs;
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}
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}
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+static void cfq_setup_merge(struct cfq_queue *cfqq, struct cfq_queue *new_cfqq)
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+{
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+ int process_refs, new_process_refs;
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+ struct cfq_queue *__cfqq;
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+
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+ /*
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+ * If there are no process references on the new_cfqq, then it is
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+ * unsafe to follow the ->new_cfqq chain as other cfqq's in the
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+ * chain may have dropped their last reference (not just their
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+ * last process reference).
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+ */
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+ if (!cfqq_process_refs(new_cfqq))
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+ return;
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+
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+ /* Avoid a circular list and skip interim queue merges */
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+ while ((__cfqq = new_cfqq->new_cfqq)) {
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+ if (__cfqq == cfqq)
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+ return;
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+ new_cfqq = __cfqq;
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+ }
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+
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+ process_refs = cfqq_process_refs(cfqq);
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+ new_process_refs = cfqq_process_refs(new_cfqq);
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+ /*
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+ * If the process for the cfqq has gone away, there is no
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+ * sense in merging the queues.
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+ */
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+ if (process_refs == 0 || new_process_refs == 0)
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+ return;
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+
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+ /*
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+ * Merge in the direction of the lesser amount of work.
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+ */
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+ if (new_process_refs >= process_refs) {
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+ cfqq->new_cfqq = new_cfqq;
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+ new_cfqq->ref += process_refs;
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+ } else {
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+ new_cfqq->new_cfqq = cfqq;
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+ cfqq->ref += new_process_refs;
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+ }
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+}
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+
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+static enum wl_type_t cfq_choose_wl(struct cfq_data *cfqd,
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+ struct cfq_group *cfqg, enum wl_prio_t prio)
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+{
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+ struct cfq_queue *queue;
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+ int i;
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+ bool key_valid = false;
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+ unsigned long lowest_key = 0;
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+ enum wl_type_t cur_best = SYNC_NOIDLE_WORKLOAD;
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+
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+ for (i = 0; i <= SYNC_WORKLOAD; ++i) {
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+ /* select the one with lowest rb_key */
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+ queue = cfq_rb_first(service_tree_for(cfqg, prio, i));
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+ if (queue &&
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+ (!key_valid || time_before(queue->rb_key, lowest_key))) {
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+ lowest_key = queue->rb_key;
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+ cur_best = i;
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+ key_valid = true;
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+ }
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+ }
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+
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+ return cur_best;
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+}
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+
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+static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
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+{
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+ unsigned slice;
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+ unsigned count;
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+ struct cfq_rb_root *st;
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+ unsigned group_slice;
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+ enum wl_prio_t original_prio = cfqd->serving_prio;
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+
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+ /* Choose next priority. RT > BE > IDLE */
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+ if (cfq_group_busy_queues_wl(RT_WORKLOAD, cfqd, cfqg))
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+ cfqd->serving_prio = RT_WORKLOAD;
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+ else if (cfq_group_busy_queues_wl(BE_WORKLOAD, cfqd, cfqg))
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+ cfqd->serving_prio = BE_WORKLOAD;
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+ else {
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+ cfqd->serving_prio = IDLE_WORKLOAD;
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+ cfqd->workload_expires = jiffies + 1;
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+ return;
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+ }
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+
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+ if (original_prio != cfqd->serving_prio)
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+ goto new_workload;
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+
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+ /*
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+ * For RT and BE, we have to choose also the type
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+ * (SYNC, SYNC_NOIDLE, ASYNC), and to compute a workload
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+ * expiration time
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+ */
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+ st = service_tree_for(cfqg, cfqd->serving_prio, cfqd->serving_type);
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+ count = st->count;
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+
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+ /*
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+ * check workload expiration, and that we still have other queues ready
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+ */
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+ if (count && !time_after(jiffies, cfqd->workload_expires))
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+ return;
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+
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+new_workload:
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+ /* otherwise select new workload type */
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