linux-kernel - Re: stable: commit "cpuidle: menu: Avoid discarding useful information" causes regressions

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Message-ID: <8da42386-282e-4f97-af93-4715ae206361@arm.com>
Date: Tue, 14 Oct 2025 11:25:07 +0100
From: Christian Loehle <christian.loehle@....com>
To: Sergey Senozhatsky <senozhatsky@...omium.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
 Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
 Artem Bityutskiy <artem.bityutskiy@...ux.intel.com>,
 Sasha Levin <sashal@...nel.org>, Daniel Lezcano <daniel.lezcano@...aro.org>,
 linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
 Tomasz Figa <tfiga@...omium.org>, stable@...r.kernel.org
Subject: Re: stable: commit "cpuidle: menu: Avoid discarding useful
 information" causes regressions

On 10/14/25 11:23, Sergey Senozhatsky wrote:
> On (25/10/14 10:50), Christian Loehle wrote:
>>> Upstream fixup fa3fa55de0d ("cpuidle: governors: menu: Avoid using
>>> invalid recent intervals data") doesn't address the problems we are
>>> observing.  Revert seems to be bringing performance metrics back to
>>> pre-regression levels.
>>
>> Any details would be much appreciated.
>> How do the idle state usages differ with and without
>> "cpuidle: menu: Avoid discarding useful information"?
>> What do the idle states look like in your platform?
> 
> Sure, I can run tests.  How do I get the numbers/stats
> that you are asking for?

Ideally just dump
cat /sys/devices/system/cpu/cpu*/cpuidle/state*/*
before and after the test.