From: Yue Hu <[email protected]>
Note that sugov_update_next_freq() may return false, that means the
caller sugov_fast_switch() will do nothing except fast switch check.
Similarly, sugov_deferred_update() also has unnecessary operations
of raw_spin_{lock,unlock} in sugov_update_single_freq() for that case.
So, let's call sugov_update_next_freq() before the fast switch check
to avoid unnecessary behaviors above. Update the related interface
definitions accordingly.
Signed-off-by: Yue Hu <[email protected]>
---
kernel/sched/cpufreq_schedutil.c | 28 ++++++++++++++--------------
1 file changed, 14 insertions(+), 14 deletions(-)
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 41e498b..d23e5be 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -114,19 +114,13 @@ static bool sugov_update_next_freq(struct sugov_policy *sg_policy, u64 time,
return true;
}
-static void sugov_fast_switch(struct sugov_policy *sg_policy, u64 time,
- unsigned int next_freq)
+static void sugov_fast_switch(struct sugov_policy *sg_policy, unsigned int next_freq)
{
- if (sugov_update_next_freq(sg_policy, time, next_freq))
- cpufreq_driver_fast_switch(sg_policy->policy, next_freq);
+ cpufreq_driver_fast_switch(sg_policy->policy, next_freq);
}
-static void sugov_deferred_update(struct sugov_policy *sg_policy, u64 time,
- unsigned int next_freq)
+static void sugov_deferred_update(struct sugov_policy *sg_policy)
{
- if (!sugov_update_next_freq(sg_policy, time, next_freq))
- return;
-
if (!sg_policy->work_in_progress) {
sg_policy->work_in_progress = true;
irq_work_queue(&sg_policy->irq_work);
@@ -368,16 +362,19 @@ static void sugov_update_single_freq(struct update_util_data *hook, u64 time,
sg_policy->cached_raw_freq = cached_freq;
}
+ if (!sugov_update_next_freq(sg_policy, time, next_f))
+ return;
+
/*
* This code runs under rq->lock for the target CPU, so it won't run
* concurrently on two different CPUs for the same target and it is not
* necessary to acquire the lock in the fast switch case.
*/
if (sg_policy->policy->fast_switch_enabled) {
- sugov_fast_switch(sg_policy, time, next_f);
+ sugov_fast_switch(sg_policy, next_f);
} else {
raw_spin_lock(&sg_policy->update_lock);
- sugov_deferred_update(sg_policy, time, next_f);
+ sugov_deferred_update(sg_policy);
raw_spin_unlock(&sg_policy->update_lock);
}
}
@@ -456,12 +453,15 @@ static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu, u64 time)
if (sugov_should_update_freq(sg_policy, time)) {
next_f = sugov_next_freq_shared(sg_cpu, time);
+ if (!sugov_update_next_freq(sg_policy, time, next_f))
+ goto unlock;
+
if (sg_policy->policy->fast_switch_enabled)
- sugov_fast_switch(sg_policy, time, next_f);
+ sugov_fast_switch(sg_policy, next_f);
else
- sugov_deferred_update(sg_policy, time, next_f);
+ sugov_deferred_update(sg_policy);
}
-
+unlock:
raw_spin_unlock(&sg_policy->update_lock);
}
--
1.9.1
On Wed, Feb 24, 2021 at 6:44 AM Yue Hu <[email protected]> wrote:
>
> From: Yue Hu <[email protected]>
>
> Note that sugov_update_next_freq() may return false, that means the
> caller sugov_fast_switch() will do nothing except fast switch check.
>
> Similarly, sugov_deferred_update() also has unnecessary operations
> of raw_spin_{lock,unlock} in sugov_update_single_freq() for that case.
>
> So, let's call sugov_update_next_freq() before the fast switch check
> to avoid unnecessary behaviors above. Update the related interface
> definitions accordingly.
>
> Signed-off-by: Yue Hu <[email protected]>
> ---
> kernel/sched/cpufreq_schedutil.c | 28 ++++++++++++++--------------
> 1 file changed, 14 insertions(+), 14 deletions(-)
>
> diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
> index 41e498b..d23e5be 100644
> --- a/kernel/sched/cpufreq_schedutil.c
> +++ b/kernel/sched/cpufreq_schedutil.c
> @@ -114,19 +114,13 @@ static bool sugov_update_next_freq(struct sugov_policy *sg_policy, u64 time,
> return true;
> }
>
> -static void sugov_fast_switch(struct sugov_policy *sg_policy, u64 time,
> - unsigned int next_freq)
> +static void sugov_fast_switch(struct sugov_policy *sg_policy, unsigned int next_freq)
> {
> - if (sugov_update_next_freq(sg_policy, time, next_freq))
> - cpufreq_driver_fast_switch(sg_policy->policy, next_freq);
> + cpufreq_driver_fast_switch(sg_policy->policy, next_freq);
> }
>
> -static void sugov_deferred_update(struct sugov_policy *sg_policy, u64 time,
> - unsigned int next_freq)
> +static void sugov_deferred_update(struct sugov_policy *sg_policy)
> {
> - if (!sugov_update_next_freq(sg_policy, time, next_freq))
> - return;
> -
> if (!sg_policy->work_in_progress) {
> sg_policy->work_in_progress = true;
> irq_work_queue(&sg_policy->irq_work);
> @@ -368,16 +362,19 @@ static void sugov_update_single_freq(struct update_util_data *hook, u64 time,
> sg_policy->cached_raw_freq = cached_freq;
> }
>
> + if (!sugov_update_next_freq(sg_policy, time, next_f))
> + return;
> +
> /*
> * This code runs under rq->lock for the target CPU, so it won't run
> * concurrently on two different CPUs for the same target and it is not
> * necessary to acquire the lock in the fast switch case.
> */
> if (sg_policy->policy->fast_switch_enabled) {
> - sugov_fast_switch(sg_policy, time, next_f);
> + sugov_fast_switch(sg_policy, next_f);
> } else {
> raw_spin_lock(&sg_policy->update_lock);
> - sugov_deferred_update(sg_policy, time, next_f);
> + sugov_deferred_update(sg_policy);
> raw_spin_unlock(&sg_policy->update_lock);
> }
> }
> @@ -456,12 +453,15 @@ static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu, u64 time)
> if (sugov_should_update_freq(sg_policy, time)) {
> next_f = sugov_next_freq_shared(sg_cpu, time);
>
> + if (!sugov_update_next_freq(sg_policy, time, next_f))
> + goto unlock;
> +
> if (sg_policy->policy->fast_switch_enabled)
> - sugov_fast_switch(sg_policy, time, next_f);
> + sugov_fast_switch(sg_policy, next_f);
> else
> - sugov_deferred_update(sg_policy, time, next_f);
> + sugov_deferred_update(sg_policy);
> }
> -
> +unlock:
> raw_spin_unlock(&sg_policy->update_lock);
> }
>
> --
Applied as 5.13 material, thanks!