sched/cpufreq: Align trace event behavior of fast switching

[ Upstream commit 77c84dd1881d0f0176cb678d770bfbda26c54390 ]

Fast switching path only emits an event for the CPU of interest, whereas the
regular path emits an event for all the CPUs that had their frequency changed,
i.e. all the CPUs sharing the same policy.

With the current behavior, looking at cpu_frequency event for a given CPU that
is using the fast switching path will not give the correct frequency signal.

Signed-off-by: Douglas RAILLARD <douglas.raillard@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index ae3ec77bb92f6d29472cc57db9bed77b1734ae85..e139b54716b4af12b4f4a044e17c1eada0cac428 100644 (file)
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -117,6 +117,7 @@ static void sugov_fast_switch(struct sugov_policy *sg_policy, u64 time,
                              unsigned int next_freq)
 {
        struct cpufreq_policy *policy = sg_policy->policy;
+       int cpu;
 
        if (!sugov_update_next_freq(sg_policy, time, next_freq))
                return;
@@ -126,7 +127,11 @@ static void sugov_fast_switch(struct sugov_policy *sg_policy, u64 time,
                return;
 
        policy->cur = next_freq;
-       trace_cpu_frequency(next_freq, smp_processor_id());
+
+       if (trace_cpu_frequency_enabled()) {
+               for_each_cpu(cpu, policy->cpus)
+                       trace_cpu_frequency(next_freq, cpu);
+       }
 }
 
 static void sugov_deferred_update(struct sugov_policy *sg_policy, u64 time,