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Message-ID: <a9e06f49-c94c-4f73-a164-0998e78914bb@arm.com>
Date: Fri, 7 Jun 2024 10:26:27 +0100
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Subject: Re: [PATCH 5/6] cpuidle: teo: Remove recent intercepts metric
To: Dietmar Eggemann <dietmar.eggemann@arm.com>, linux-pm@vger.kernel.org,
 linux-kernel@vger.kernel.org, rafael@kernel.org
Cc: vincent.guittot@linaro.org, qyousef@layalina.io, peterz@infradead.org,
 daniel.lezcano@linaro.org, anna-maria@linutronix.de,
 kajetan.puchalski@arm.com, lukasz.luba@arm.com
References: <20240606090050.327614-1-christian.loehle@arm.com>
 <20240606090050.327614-6-christian.loehle@arm.com>
 <96eb4e13-e1c7-4c64-a4bf-0d2b5610d390@arm.com>
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From: Christian Loehle <christian.loehle@arm.com>
In-Reply-To: <96eb4e13-e1c7-4c64-a4bf-0d2b5610d390@arm.com>
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On 6/7/24 09:57, Dietmar Eggemann wrote:
> On 06/06/2024 11:00, Christian Loehle wrote:
>> The logic for recent intercepts didn't work, there is an underflow
>> that can be observed during boot already, which teo usually doesn't
>> recover from, making the entire logic pointless.
> 
> Is this related to:
> 
> https://lkml.kernel.org/r/0ce2d536-1125-4df8-9a5b-0d5e389cd8af@arm.com ?
> 
> In this case, a link here would be helpful to get the story.

It is!
Will include. To my defense, it is included in the cover letter.

> 
>> Furthermore the recent intercepts also were never reset, thus not
>> actually being very 'recent'.
>>
>> If it turns out to be necessary to focus more heavily on resets, the
>> intercepts metric also could be adjusted to decay more quickly.
>>
>> Fixes: 77577558f25d ("cpuidle: teo: Rework most recent idle duration values treatment")
>> Signed-off-by: Christian Loehle <christian.loehle@arm.com>
> 
> [...]
>