[PATCH 1/2] sched/fair: move cpufreq hook to update_cfs_rq_load_avg()

Steve Muckle
2016-03-22T00:21:14Z

The cpufreq hook should be called whenever the root cfs_rq
utilization changes so update_cfs_rq_load_avg() is a better
place for it. The current location is not invoked in the
enqueue_entity() or update_blocked_averages() paths.

Suggested-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Steve Muckle <smuckle@linaro.org>
---
kernel/sched/fair.c | 50 ++++++++++++++++++++++++++------------------------
1 file changed, 26 insertions(+), 24 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 46d64e4ccfde..d418deb04049 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2825,7 +2825,9 @@ static inline u64 cfs_rq_clock_task(struct cfs_rq *cfs_rq);
static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq)
{
struct sched_avg *sa = &cfs_rq->avg;
+ struct rq *rq = rq_of(cfs_rq);
int decayed, removed = 0;
+ int cpu = cpu_of(rq);

if (atomic_long_read(&cfs_rq->removed_load_avg)) {
s64 r = atomic_long_xchg(&cfs_rq->removed_load_avg, 0);
@@ -2840,7 +2842,7 @@ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq)
sa->util_sum = max_t(s32, sa->util_sum - r * LOAD_AVG_MAX, 0);
}

- decayed = __update_load_avg(now, cpu_of(rq_of(cfs_rq)), sa,
+ decayed = __update_load_avg(now, cpu, sa,
scale_load_down(cfs_rq->load.weight), cfs_rq->curr != NULL, cfs_rq);

#ifndef CONFIG_64BIT
@@ -2848,28 +2850,6 @@ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq)
cfs_rq->load_last_update_time_copy = sa->last_update_time;
#endif

- return decayed || removed;
-}
-
-/* Update task and its cfs_rq load average */
-static inline void update_load_avg(struct sched_entity *se, int update_tg)
-{
- struct cfs_rq *cfs_rq = cfs_rq_of(se);
- u64 now = cfs_rq_clock_task(cfs_rq);
- struct rq *rq = rq_of(cfs_rq);
- int cpu = cpu_of(rq);
-
- /*
- * Track task load average for carrying it to new CPU after migrated, and
- * track group sched_entity load average for task_h_load calc in migration
- */
- __update_load_avg(now, cpu, &se->avg,
- se->on_rq * scale_load_down(se->load.weight),
- cfs_rq->curr == se, NULL);
-
- if (update_cfs_rq_load_avg(now, cfs_rq) && update_tg)
- update_tg_load_avg(cfs_rq, 0);
-
if (cpu == smp_processor_id() && &rq->cfs == cfs_rq) {
unsigned long max = rq->cpu_capacity_orig;

@@ -2890,8 +2870,30 @@ static inline void update_load_avg(struct sched_entity *se, int update_tg)
* See cpu_util().
*/
cpufreq_update_util(rq_clock(rq),
- min(cfs_rq->avg.util_avg, max), max);
+ min(sa->util_avg, max), max);
}
+
+ return decayed || removed;
+}
+
+/* Update task and its cfs_rq load average */
+static inline void update_load_avg(struct sched_entity *se, int update_tg)
+{
+ struct cfs_rq *cfs_rq = cfs_rq_of(se);
+ u64 now = cfs_rq_clock_task(cfs_rq);
+ struct rq *rq = rq_of(cfs_rq);
+ int cpu = cpu_of(rq);
+
+ /*
+ * Track task load average for carrying it to new CPU after migrated, and
+ * track group sched_entity load average for task_h_load calc in migration
+ */
+ __update_load_avg(now, cpu, &se->avg,
+ se->on_rq * scale_load_down(se->load.weight),
+ cfs_rq->curr == se, NULL);
+
+ if (update_cfs_rq_load_avg(now, cfs_rq) && update_tg)
+ update_tg_load_avg(cfs_rq, 0);
}

static void attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
--
2.4.10