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Subject: Re: [RFC,v2 3/3] sched: ignore task_h_load for CPU_NEWLY_IDLE
To: Uladzislau Rezki <urezki@gmail.com>,
        Peter Zijlstra <peterz@infradead.org>
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Cc: Ingo Molnar <mingo@redhat.com>, LKML <linux-kernel@vger.kernel.org>,
        Uladzislau 2 Rezki <uladzislau2.rezki@sonymobile.com>
From: Dietmar Eggemann <dietmar.eggemann@arm.com>
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Date: Wed, 15 Feb 2017 18:58:46 +0000
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On 02/14/2017 06:28 PM, Uladzislau Rezki wrote:
>>>
>>> So that is useful information that should have been in the Changelog.
>>>
>>> OK, can you respin this patch with adjusted Changelog and taking Mike's
>>> feedback?
>>>
>> Yes, i will prepare a patch accordingly, no problem.
>>
>>>
>>> Also, I worry about the effects of this on !PREEMPT kernels, the first
>>> hunk (which explicitly states is about latency) should be under
>>> CONFIG_PREEMPT to match the similar case we already have in
>>> detach_tasks().

This one uses #ifdef CONFIG_PREEMPT whereas you use 
IS_ENABLED(CONFIG_PREEMPT). Is there a particular reason for this?

>>> But your second hunk, which ignores the actual load of tasks in favour
>>> of just moving _something_ already, is utterly dangerous if not coupled
>>> with these two other conditions, so arguably that too should be under
>>> CONFIG_PREEMPT.
>>>
>> I see your point. Will round both with CONFIG_PREEMPT.
>>
> I have upload a new patch, please find it here:
> https://lkml.org/lkml/2017/2/14/334
>