Re: [RFC 3/3] Allow sched_{get,set}attr to change latency_tolerance of the task

From: Parth Shah
Date: Sun Dec 08 2019 - 00:52:41 EST




On 12/6/19 9:34 PM, Dietmar Eggemann wrote:
>
>
> On 05.12.19 10:24, Dietmar Eggemann wrote:
>> On 03/12/2019 16:51, Parth Shah wrote:
>>>
>>> On 12/3/19 2:09 PM, Qais Yousef wrote:
>>>> On 11/25/19 15:16, Parth Shah wrote:
>>
>> [...]
>>
>>>>> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
>>>>> index ea7abbf5c1bb..dfd36ec14404 100644
>>>>> --- a/kernel/sched/core.c
>>>>> +++ b/kernel/sched/core.c
>>>>> @@ -4695,6 +4695,9 @@ static void __setscheduler_params(struct task_struct *p,
>>>>> p->rt_priority = attr->sched_priority;
>>>>> p->normal_prio = normal_prio(p);
>>>>> set_load_weight(p, true);
>>>>> +
>>>>> + /* Change latency tolerance of the task if !SCHED_FLAG_KEEP_PARAMS */
>>
>> IMHO, this comment seems to be gratuitous.
>>
>>>>> + p->latency_tolerance = attr->sched_latency_tolerance;
>>>>> }
>>
>> [...]
>>
>
> This also would require some changes to UAPI
> (include/uapi/linux/sched.h, include/uapi/linux/sched/types.h), see
> commit a509a7cd7974 ("sched/uclamp: Extend sched_setattr() to support
> utilization clamping") and tools headers UAPI
> (tools/include/uapi/linux/sched.h), see commit c093de6bd3c5 ("tools
> headers UAPI: Sync sched.h with the kernel").
>

Ok. Will add it. Thanks