2019-10-22 23:54:33

by Thara Gopinath

Subject: [Patch v4 3/6] sched/fair: Enable CFS periodic tick to update thermal pressure

Introduce support in CFS periodic tick to trigger the process of
computing average thermal pressure for a cpu.

Signed-off-by: Thara Gopinath <[email protected]>
---
kernel/sched/fair.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 682a754..4f9c2cb 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -21,6 +21,7 @@
* Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
*/
#include "sched.h"
+#include "thermal.h"

#include <trace/events/sched.h>

@@ -7574,6 +7575,8 @@ static void update_blocked_averages(int cpu)
done = false;

update_blocked_load_status(rq, !done);
+
+ trigger_thermal_pressure_average(rq);
rq_unlock_irqrestore(rq, &rf);
}

@@ -9933,6 +9936,8 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued)

update_misfit_status(curr, rq);
update_overutilized_status(task_rq(curr));
+
+ trigger_thermal_pressure_average(rq);
}

/*
--
2.1.4

2019-10-28 21:11:47

by Peter Zijlstra

Subject: Re: [Patch v4 3/6] sched/fair: Enable CFS periodic tick to update thermal pressure

On Tue, Oct 22, 2019 at 04:34:22PM -0400, Thara Gopinath wrote:
> Introduce support in CFS periodic tick to trigger the process of
> computing average thermal pressure for a cpu.
>
> Signed-off-by: Thara Gopinath <[email protected]>
> ---
> kernel/sched/fair.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 682a754..4f9c2cb 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -21,6 +21,7 @@
> * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
> */
> #include "sched.h"
> +#include "thermal.h"
>
> #include <trace/events/sched.h>
>
> @@ -7574,6 +7575,8 @@ static void update_blocked_averages(int cpu)
> done = false;
>
> update_blocked_load_status(rq, !done);
> +
> + trigger_thermal_pressure_average(rq);
> rq_unlock_irqrestore(rq, &rf);
> }

This changes only 1 of the 2 implementations of
update_blocked_averages(). Also, how does this interact with
rq->has_blocked_load ?

> @@ -9933,6 +9936,8 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued)
>
> update_misfit_status(curr, rq);
> update_overutilized_status(task_rq(curr));
> +
> + trigger_thermal_pressure_average(rq);
> }

This seems to imply all this thermal stuff is fair only, in which case I
could suggest putting those few lines in fair.c. ~45 extra lines on
1e5+ lines really doesn't matter.

2019-10-28 21:11:54

by Peter Zijlstra

Subject: Re: [Patch v4 3/6] sched/fair: Enable CFS periodic tick to update thermal pressure

On Mon, Oct 28, 2019 at 04:24:21PM +0100, Peter Zijlstra wrote:
> On Tue, Oct 22, 2019 at 04:34:22PM -0400, Thara Gopinath wrote:
> > Introduce support in CFS periodic tick to trigger the process of
> > computing average thermal pressure for a cpu.
> >
> > Signed-off-by: Thara Gopinath <[email protected]>
> > ---
> > kernel/sched/fair.c | 5 +++++
> > 1 file changed, 5 insertions(+)
> >
> > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> > index 682a754..4f9c2cb 100644
> > --- a/kernel/sched/fair.c
> > +++ b/kernel/sched/fair.c
> > @@ -21,6 +21,7 @@
> > * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
> > */
> > #include "sched.h"
> > +#include "thermal.h"
> >
> > #include <trace/events/sched.h>
> >
> > @@ -7574,6 +7575,8 @@ static void update_blocked_averages(int cpu)
> > done = false;
> >
> > update_blocked_load_status(rq, !done);
> > +
> > + trigger_thermal_pressure_average(rq);
> > rq_unlock_irqrestore(rq, &rf);
> > }
>
> This changes only 1 of the 2 implementations of
> update_blocked_averages(). Also, how does this interact with
> rq->has_blocked_load ?

Specifically, I'm thikning this wants a line in others_have_blocked():

+ if (READ_ONCE(rq->avg_thermal.load_avg))
+ return true;

2019-10-30 21:44:55

by Thara Gopinath

Subject: Re: [Patch v4 3/6] sched/fair: Enable CFS periodic tick to update thermal pressure

On 10/28/2019 11:24 AM, Peter Zijlstra wrote:
> On Tue, Oct 22, 2019 at 04:34:22PM -0400, Thara Gopinath wrote:
>> Introduce support in CFS periodic tick to trigger the process of
>> computing average thermal pressure for a cpu.
>>
>> Signed-off-by: Thara Gopinath <[email protected]>
>> ---
>> kernel/sched/fair.c | 5 +++++
>> 1 file changed, 5 insertions(+)
>>
>> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
>> index 682a754..4f9c2cb 100644
>> --- a/kernel/sched/fair.c
>> +++ b/kernel/sched/fair.c
>> @@ -21,6 +21,7 @@
>> * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
>> */
>> #include "sched.h"
>> +#include "thermal.h"
>>
>> #include <trace/events/sched.h>
>>
>> @@ -7574,6 +7575,8 @@ static void update_blocked_averages(int cpu)
>> done = false;
>>
>> update_blocked_load_status(rq, !done);
>> +
>> + trigger_thermal_pressure_average(rq);
>> rq_unlock_irqrestore(rq, &rf);
>> }
>
> This changes only 1 of the 2 implementations of
> update_blocked_averages(). Also, how does this interact with
> rq->has_blocked_load ?
I will add it to the other implementation of update_blocked_averages and
will also update others_have_blocked.
>
>> @@ -9933,6 +9936,8 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued)
>>
>> update_misfit_status(curr, rq);
>> update_overutilized_status(task_rq(curr));
>> +
>> + trigger_thermal_pressure_average(rq);
>> }
>
> This seems to imply all this thermal stuff is fair only, in which case I
> could suggest putting those few lines in fair.c. ~45 extra lines on
> 1e5+ lines really doesn't matter.
>


--
Warm Regards
Thara

2019-10-31 16:15:33

by Dietmar Eggemann

Subject: Re: [Patch v4 3/6] sched/fair: Enable CFS periodic tick to update thermal pressure

On 22.10.19 22:34, Thara Gopinath wrote:
> Introduce support in CFS periodic tick to trigger the process of
> computing average thermal pressure for a cpu.
>
> Signed-off-by: Thara Gopinath <[email protected]>
> ---
> kernel/sched/fair.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 682a754..4f9c2cb 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -21,6 +21,7 @@
> * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
> */
> #include "sched.h"
> +#include "thermal.h"
>
> #include <trace/events/sched.h>
>
> @@ -7574,6 +7575,8 @@ static void update_blocked_averages(int cpu)
> done = false;
>
> update_blocked_load_status(rq, !done);
> +
> + trigger_thermal_pressure_average(rq);
> rq_unlock_irqrestore(rq, &rf);
> }

Since you update the thermal pressure signal in CFS's
update_blocked_averages() as well, I guess the patch title has to change.

>
> @@ -9933,6 +9936,8 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued)
>
> update_misfit_status(curr, rq);
> update_overutilized_status(task_rq(curr));
> +
> + trigger_thermal_pressure_average(rq);
> }
>
> /*
>

2019-10-31 16:50:24

by Thara Gopinath

Subject: Re: [Patch v4 3/6] sched/fair: Enable CFS periodic tick to update thermal pressure

On 10/31/2019 12:11 PM, Dietmar Eggemann wrote:
> On 22.10.19 22:34, Thara Gopinath wrote:
>> Introduce support in CFS periodic tick to trigger the process of
>> computing average thermal pressure for a cpu.
>>
>> Signed-off-by: Thara Gopinath <[email protected]>
>> ---
>> kernel/sched/fair.c | 5 +++++
>> 1 file changed, 5 insertions(+)
>>
>> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
>> index 682a754..4f9c2cb 100644
>> --- a/kernel/sched/fair.c
>> +++ b/kernel/sched/fair.c
>> @@ -21,6 +21,7 @@
>> * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
>> */
>> #include "sched.h"
>> +#include "thermal.h"
>>
>> #include <trace/events/sched.h>
>>
>> @@ -7574,6 +7575,8 @@ static void update_blocked_averages(int cpu)
>> done = false;
>>
>> update_blocked_load_status(rq, !done);
>> +
>> + trigger_thermal_pressure_average(rq);
>> rq_unlock_irqrestore(rq, &rf);
>> }
>
> Since you update the thermal pressure signal in CFS's
> update_blocked_averages() as well, I guess the patch title has to change.
Will do. Thanks.
>
>>
>> @@ -9933,6 +9936,8 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued)
>>
>> update_misfit_status(curr, rq);
>> update_overutilized_status(task_rq(curr));
>> +
>> + trigger_thermal_pressure_average(rq);
>> }
>>
>> /*
>>


--
Warm Regards
Thara