summaryrefslogtreecommitdiffstats
path: root/block/blk-rq-qos.c
diff options
context:
space:
mode:
Diffstat (limited to 'block/blk-rq-qos.c')
-rw-r--r--block/blk-rq-qos.c14
1 files changed, 9 insertions, 5 deletions
diff --git a/block/blk-rq-qos.c b/block/blk-rq-qos.c
index 61b635bc2a31..656460636ad3 100644
--- a/block/blk-rq-qos.c
+++ b/block/blk-rq-qos.c
@@ -160,24 +160,27 @@ bool rq_depth_calc_max_depth(struct rq_depth *rqd)
return ret;
}
-void rq_depth_scale_up(struct rq_depth *rqd)
+/* Returns true on success and false if scaling up wasn't possible */
+bool rq_depth_scale_up(struct rq_depth *rqd)
{
/*
* Hit max in previous round, stop here
*/
if (rqd->scaled_max)
- return;
+ return false;
rqd->scale_step--;
rqd->scaled_max = rq_depth_calc_max_depth(rqd);
+ return true;
}
/*
* Scale rwb down. If 'hard_throttle' is set, do it quicker, since we
- * had a latency violation.
+ * had a latency violation. Returns true on success and returns false if
+ * scaling down wasn't possible.
*/
-void rq_depth_scale_down(struct rq_depth *rqd, bool hard_throttle)
+bool rq_depth_scale_down(struct rq_depth *rqd, bool hard_throttle)
{
/*
* Stop scaling down when we've hit the limit. This also prevents
@@ -185,7 +188,7 @@ void rq_depth_scale_down(struct rq_depth *rqd, bool hard_throttle)
* keep up.
*/
if (rqd->max_depth == 1)
- return;
+ return false;
if (rqd->scale_step < 0 && hard_throttle)
rqd->scale_step = 0;
@@ -194,6 +197,7 @@ void rq_depth_scale_down(struct rq_depth *rqd, bool hard_throttle)
rqd->scaled_max = false;
rq_depth_calc_max_depth(rqd);
+ return true;
}
struct rq_qos_wait_data {