There's no reason to call the cpufreq hook if the root cfs_rq
utilization has not been modified.

Signed-off-by: Steve Muckle <[email protected]>
---
 kernel/sched/fair.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index d418deb04049..af58e826cffe 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2826,20 +2826,21 @@ 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 decayed, removed_load = 0, removed_util = 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);
                sa->load_avg = max_t(long, sa->load_avg - r, 0);
                sa->load_sum = max_t(s64, sa->load_sum - r * LOAD_AVG_MAX, 0);
-               removed = 1;
+               removed_load = 1;
        }
 
        if (atomic_long_read(&cfs_rq->removed_util_avg)) {
                long r = atomic_long_xchg(&cfs_rq->removed_util_avg, 0);
                sa->util_avg = max_t(long, sa->util_avg - r, 0);
                sa->util_sum = max_t(s32, sa->util_sum - r * LOAD_AVG_MAX, 0);
+               removed_util = 1;
        }
 
        decayed = __update_load_avg(now, cpu, sa,
@@ -2850,7 +2851,8 @@ 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
 
-       if (cpu == smp_processor_id() && &rq->cfs == cfs_rq) {
+       if (cpu == smp_processor_id() && &rq->cfs == cfs_rq &&
+           (decayed || removed_util)) {
                unsigned long max = rq->cpu_capacity_orig;
 
                /*
@@ -2873,7 +2875,7 @@ static inline int update_cfs_rq_load_avg(u64 now, struct 
cfs_rq *cfs_rq)
                                    min(sa->util_avg, max), max);
        }
 
-       return decayed || removed;
+       return decayed || removed_load;
 }
 
 /* Update task and its cfs_rq load average */
-- 
2.4.10

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