netns xfrm: fix "ip xfrm state|policy count" misreport
[safe/jmp/linux-2.6] / block / cfq-iosched.c
index 8df4fe5..ee130f1 100644 (file)
@@ -1667,13 +1667,17 @@ static inline sector_t cfq_dist_from_last(struct cfq_data *cfqd,
 #define CFQQ_SEEKY(cfqq)       ((cfqq)->seek_mean > CFQQ_SEEK_THR)
 
 static inline int cfq_rq_close(struct cfq_data *cfqd, struct cfq_queue *cfqq,
-                              struct request *rq)
+                              struct request *rq, bool for_preempt)
 {
        sector_t sdist = cfqq->seek_mean;
 
        if (!sample_valid(cfqq->seek_samples))
                sdist = CFQQ_SEEK_THR;
 
+       /* if seek_mean is big, using it as close criteria is meaningless */
+       if (sdist > CFQQ_SEEK_THR && !for_preempt)
+               sdist = CFQQ_SEEK_THR;
+
        return cfq_dist_from_last(cfqd, rq) <= sdist;
 }
 
@@ -1701,7 +1705,7 @@ static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
         * will contain the closest sector.
         */
        __cfqq = rb_entry(parent, struct cfq_queue, p_node);
-       if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq))
+       if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq, false))
                return __cfqq;
 
        if (blk_rq_pos(__cfqq->next_rq) < sector)
@@ -1712,7 +1716,7 @@ static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
                return NULL;
 
        __cfqq = rb_entry(node, struct cfq_queue, p_node);
-       if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq))
+       if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq, false))
                return __cfqq;
 
        return NULL;
@@ -3073,6 +3077,12 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
                return true;
 
        /*
+        * Don't allow a non-RT request to preempt an ongoing RT cfqq timeslice.
+        */
+       if (cfq_class_rt(cfqq) && !cfq_class_rt(new_cfqq))
+               return false;
+
+       /*
         * if the new request is sync, but the currently running queue is
         * not, let the sync request have priority.
         */
@@ -3112,7 +3122,7 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
         * if this request is as-good as one we would expect from the
         * current cfqq, let it preempt
         */
-       if (cfq_rq_close(cfqd, cfqq, rq))
+       if (cfq_rq_close(cfqd, cfqq, rq, true))
                return true;
 
        return false;