Re: [External] Re: [PATCH v2 06/10] sched/fair: delete superfluous SKIP_AGE_LOAD

From: Chengming Zhou
Date: Thu Jul 14 2022 - 09:25:05 EST


On 2022/7/14 20:33, Dietmar Eggemann wrote:
> On 13/07/2022 06:04, Chengming Zhou wrote:
>> There are three types of attach_entity_cfs_rq():
>>
>> 1. task migrate to CPU
>> 2. task move to cgroup
>> 3. task switched to fair from !fair
>>
>> The case1 and case2 already have sched_avg last_update_time
>> reset to 0 when attach_entity_cfs_rq().
>>
>> We will make case3 also have last_update_time reset to 0 when
>> attach_entity_cfs_rq() in the following patches.
>>
>> So it makes no difference whether SKIP_AGE_LOAD is set or not.
>
> Wouldn't this patch make more sense after 09/10?
>

Yes, this patch was put at last in the v1.

In this v2, the following patch 07/10 make attach_entity_cfs_rq() to use
update_load_avg(DO_ATTACH) to do conditional attach.

So I want to get rid of "sched_feat(ATTACH_AGE_LOAD) ? 0 : SKIP_AGE_LOAD"
earlier in this patch, or have to write like this:


int flags = UPDATE_TG | DO_ATTACH;

update_load_avg(cfs_rq, se, sched_feat(ATTACH_AGE_LOAD) ? flags : SKIP_AGE_LOAD | flags);


Thanks.

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