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Subject: Re: [RFC PATCH 2/5] sched/events: Introduce cfs_rq load tracking
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To: Peter Zijlstra <peterz@infradead.org>
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From: Dietmar Eggemann <dietmar.eggemann@arm.com>
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Date: Thu, 30 Mar 2017 09:46:22 +0200
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On 03/30/2017 09:04 AM, Peter Zijlstra wrote:
> On Wed, Mar 29, 2017 at 11:03:45PM +0200, Dietmar Eggemann wrote:

[...]

>> Why not reduce the parameter list of these 3 incarnations to 'now, cpu,
>> object'?
>>
>> static int
>> __update_load_avg_blocked_se(u64 now, int cpu, struct sched_entity *se)
>>
>> static int
>> __update_load_avg_se(u64 now, int cpu, struct sched_entity *se)
>>
>> static int
>> __update_load_avg_cfs_rq(u64 now, int cpu, struct cfs_rq *cfs_rq)
>>
>> [...]
>
> doesn't quite work with se, but yes good idea.

Ah, OK, you don't like to use 'cfs_rq_of(se)->curr == se' in 
__update_load_avg_se(). The reason is that it's already fetched in 
update_load_avg()?

> And this way we don't need the nonnull attribute either, because it
> should be clear from having dereferenced it that it cannot be null.

Yes, this would be clearer now.

[...]