cpufreq: Convert printk(KERN_<LEVEL> to pr_<level>

[cascardo/linux.git] / block / cfq-iosched.c

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 1f9093e..e3c591d 100644 (file)
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -632,6 +632,13 @@ static inline struct cfq_group *cfqg_parent(struct cfq_group *cfqg)
        return pblkg ? blkg_to_cfqg(pblkg) : NULL;
 }
 
+static inline bool cfqg_is_descendant(struct cfq_group *cfqg,
+                                     struct cfq_group *ancestor)
+{
+       return cgroup_is_descendant(cfqg_to_blkg(cfqg)->blkcg->css.cgroup,
+                                   cfqg_to_blkg(ancestor)->blkcg->css.cgroup);
+}
+
 static inline void cfqg_get(struct cfq_group *cfqg)
 {
        return blkg_get(cfqg_to_blkg(cfqg));
@@ -758,6 +765,11 @@ static void cfqg_stats_xfer_dead(struct cfq_group *cfqg)
 #else  /* CONFIG_CFQ_GROUP_IOSCHED */
 
 static inline struct cfq_group *cfqg_parent(struct cfq_group *cfqg) { return NULL; }
+static inline bool cfqg_is_descendant(struct cfq_group *cfqg,
+                                     struct cfq_group *ancestor)
+{
+       return true;
+}
 static inline void cfqg_get(struct cfq_group *cfqg) { }
 static inline void cfqg_put(struct cfq_group *cfqg) { }
 
@@ -2897,6 +2909,7 @@ static bool cfq_should_idle(struct cfq_data *cfqd, struct cfq_queue *cfqq)
 static void cfq_arm_slice_timer(struct cfq_data *cfqd)
 {
        struct cfq_queue *cfqq = cfqd->active_queue;
+       struct cfq_rb_root *st = cfqq->service_tree;
        struct cfq_io_cq *cic;
        unsigned long sl, group_idle = 0;
 
@@ -2947,8 +2960,13 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
                return;
        }
 
-       /* There are other queues in the group, don't do group idle */
-       if (group_idle && cfqq->cfqg->nr_cfqq > 1)
+       /*
+        * There are other queues in the group or this is the only group and
+        * it has too big thinktime, don't do group idle.
+        */
+       if (group_idle &&
+           (cfqq->cfqg->nr_cfqq > 1 ||
+            cfq_io_thinktime_big(cfqd, &st->ttime, true)))
                return;
 
        cfq_mark_cfqq_wait_request(cfqq);
@@ -3947,16 +3965,27 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
        if (rq_is_sync(rq) && !cfq_cfqq_sync(cfqq))
                return true;
 
-       if (new_cfqq->cfqg != cfqq->cfqg)
+       /*
+        * Treat ancestors of current cgroup the same way as current cgroup.
+        * For anybody else we disallow preemption to guarantee service
+        * fairness among cgroups.
+        */
+       if (!cfqg_is_descendant(cfqq->cfqg, new_cfqq->cfqg))
                return false;
 
        if (cfq_slice_used(cfqq))
                return true;
 
+       /*
+        * Allow an RT request to pre-empt an ongoing non-RT cfqq timeslice.
+        */
+       if (cfq_class_rt(new_cfqq) && !cfq_class_rt(cfqq))
+               return true;
+
+       WARN_ON_ONCE(cfqq->ioprio_class != new_cfqq->ioprio_class);
        /* Allow preemption only if we are idling on sync-noidle tree */
        if (cfqd->serving_wl_type == SYNC_NOIDLE_WORKLOAD &&
            cfqq_type(new_cfqq) == SYNC_NOIDLE_WORKLOAD &&
-           new_cfqq->service_tree->count == 2 &&
            RB_EMPTY_ROOT(&cfqq->sort_list))
                return true;
 
@@ -3967,12 +3996,6 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
        if ((rq->cmd_flags & REQ_PRIO) && !cfqq->prio_pending)
                return true;
 
-       /*
-        * Allow an RT request to pre-empt an ongoing non-RT cfqq timeslice.
-        */
-       if (cfq_class_rt(new_cfqq) && !cfq_class_rt(cfqq))
-               return true;
-
        /* An idle queue should not be idle now for some reason */
        if (RB_EMPTY_ROOT(&cfqq->sort_list) && !cfq_should_idle(cfqd, cfqq))
                return true;