Re: [RFC PATCH 3/9] sched: add sched feature to disable idle core search
On 9/5/19 3:17 AM, Patrick Bellasi wrote:
On Fri, Aug 30, 2019 at 18:49:38 +0100, subhra mazumdar wrote...
Add a new sched feature SIS_CORE to have an option to disable idle core
search (select_idle_core).
Signed-off-by: subhra mazumdar
---
kernel/sched/features.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/sched/features.h b/kernel/sched/features.h
index 858589b..de4d506 100644
--- a/kernel/sched/features.h
+++ b/kernel/sched/features.h
@@ -57,6 +57,7 @@ SCHED_FEAT(TTWU_QUEUE, true)
*/
SCHED_FEAT(SIS_AVG_CPU, false)
SCHED_FEAT(SIS_PROP, true)
+SCHED_FEAT(SIS_CORE, true)
Why do we need a sched_feature? If you think there are systems in
which the usage of latency-nice does not make sense for in "Select Idle
Sibling", then we should probably better add a new Kconfig option.
This is not for latency-nice but to be able to disable a different aspect
of the scheduler, i.e searching for idle cores. This can be made part of
latency-nice (i.e not do idle core search if latency-nice is below a
certain value) but even then having a feature to disable it doesn't hurt.
If that's the case, you can probably use the init/Kconfig's
"Scheduler features" section, recently added by:
commit 69842cba9ace ("sched/uclamp: Add CPU's clamp buckets refcounting")
/*
* Issue a WARN when we do multiple update_rq_clock() calls
Best,
Patrick
Re: [RFC PATCH 3/9] sched: add sched feature to disable idle core search
On Fri, Aug 30, 2019 at 18:49:38 +0100, subhra mazumdar wrote...
> Add a new sched feature SIS_CORE to have an option to disable idle core
> search (select_idle_core).
>
> Signed-off-by: subhra mazumdar
> ---
> kernel/sched/features.h | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/kernel/sched/features.h b/kernel/sched/features.h
> index 858589b..de4d506 100644
> --- a/kernel/sched/features.h
> +++ b/kernel/sched/features.h
> @@ -57,6 +57,7 @@ SCHED_FEAT(TTWU_QUEUE, true)
> */
> SCHED_FEAT(SIS_AVG_CPU, false)
> SCHED_FEAT(SIS_PROP, true)
> +SCHED_FEAT(SIS_CORE, true)
Why do we need a sched_feature? If you think there are systems in
which the usage of latency-nice does not make sense for in "Select Idle
Sibling", then we should probably better add a new Kconfig option.
If that's the case, you can probably use the init/Kconfig's
"Scheduler features" section, recently added by:
commit 69842cba9ace ("sched/uclamp: Add CPU's clamp buckets refcounting")
> /*
> * Issue a WARN when we do multiple update_rq_clock() calls
Best,
Patrick
--
#include
Patrick Bellasi
[RFC PATCH 3/9] sched: add sched feature to disable idle core search
Add a new sched feature SIS_CORE to have an option to disable idle core search (select_idle_core). Signed-off-by: subhra mazumdar --- kernel/sched/features.h | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/sched/features.h b/kernel/sched/features.h index 858589b..de4d506 100644 --- a/kernel/sched/features.h +++ b/kernel/sched/features.h @@ -57,6 +57,7 @@ SCHED_FEAT(TTWU_QUEUE, true) */ SCHED_FEAT(SIS_AVG_CPU, false) SCHED_FEAT(SIS_PROP, true) +SCHED_FEAT(SIS_CORE, true) /* * Issue a WARN when we do multiple update_rq_clock() calls -- 2.9.3
