1 files changed, 15 insertions, 2 deletions

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index da69b079725f..b7e9c7feeab2 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -38,9 +38,13 @@ static const u64 cfq_target_latency = (u64)NSEC_PER_SEC * 3/10; /* 300 ms */
 static const int cfq_hist_divisor = 4;
 
 /*
- * offset from end of service tree
+ * offset from end of queue service tree for idle class
  */
 #define CFQ_IDLE_DELAY          (NSEC_PER_SEC / 5)
+/* offset from end of group service tree under time slice mode */
+#define CFQ_SLICE_MODE_GROUP_DELAY (NSEC_PER_SEC / 5)
+/* offset from end of group service under IOPS mode */
+#define CFQ_IOPS_MODE_GROUP_DELAY (HZ / 5)
 
 /*
  * below this threshold, we consider thinktime immediate
@@ -1362,6 +1366,14 @@ cfq_group_service_tree_add(struct cfq_rb_root *st, struct cfq_group *cfqg)
         cfqg->vfraction = max_t(unsigned, vfr, 1);
 }
 
+static inline u64 cfq_get_cfqg_vdisktime_delay(struct cfq_data *cfqd)
+{
+        if (!iops_mode(cfqd))
+                return CFQ_SLICE_MODE_GROUP_DELAY;
+        else
+                return CFQ_IOPS_MODE_GROUP_DELAY;
+}
+
 static void
 cfq_group_notify_queue_add(struct cfq_data *cfqd, struct cfq_group *cfqg)
 {
@@ -1381,7 +1393,8 @@ cfq_group_notify_queue_add(struct cfq_data *cfqd, struct cfq_group *cfqg)
         n = rb_last(&st->rb);
         if (n) {
                 __cfqg = rb_entry_cfqg(n);
-                cfqg->vdisktime = __cfqg->vdisktime + CFQ_IDLE_DELAY;
+                cfqg->vdisktime = __cfqg->vdisktime +
+                        cfq_get_cfqg_vdisktime_delay(cfqd);
         } else
                 cfqg->vdisktime = st->min_vdisktime;
         cfq_group_service_tree_add(st, cfqg);