From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 0D10E2E2EF8; Tue, 14 Oct 2025 10:25:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760437512; cv=none; b=ouL/u17KqSRzxEoeN7x3/9Yt5nIsKNqSlJRhvoAWIjhBZ/ZkuCi90WFIrdUsAW0EqK9o5s6chWRo1QolWHIrXEkVLVL2j9GJ+3k0+mn4KWFW65m4hCElbg2C3+I3d9rzAPQRrKTe9IKwnp9FVdiL9myuRI90+be9R6aDnGwYA9o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760437512; c=relaxed/simple; bh=GrPWHejUInShSTEIrfwfdYR823L0J0oxHEJVM90GmJs=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=hTsKOAkhoRFGYBROChRH5aNGaYm9CSWXmuuXtbmooT0rM20A8dGgiO6ZD3g+NTA9BkA50/k1AGreIibOvHXiMXEvTjBU7h1pPBxZFKcBPJ1FSc7DLYJ3kGauDy05HshSZYHR/9aBpEJGNMjGH0mp6jIppT2dyEm6CV42kczGcT4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 70DBE1A9A; Tue, 14 Oct 2025 03:25:02 -0700 (PDT) Received: from [10.57.66.74] (unknown [10.57.66.74]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E88D33F6A8; Tue, 14 Oct 2025 03:25:08 -0700 (PDT) Message-ID: <8da42386-282e-4f97-af93-4715ae206361@arm.com> Date: Tue, 14 Oct 2025 11:25:07 +0100 Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: stable: commit "cpuidle: menu: Avoid discarding useful information" causes regressions To: Sergey Senozhatsky Cc: "Rafael J. Wysocki" , Greg Kroah-Hartman , Artem Bityutskiy , Sasha Levin , Daniel Lezcano , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Tomasz Figa , stable@vger.kernel.org References: <36iykr223vmcfsoysexug6s274nq2oimcu55ybn6ww4il3g3cv@cohflgdbpnq7> <08529809-5ca1-4495-8160-15d8e85ad640@arm.com> <2zreguw4djctgcmvgticnm4dctcuja7yfnp3r6bxaqon3i2pxf@thee3p3qduoq> Content-Language: en-US From: Christian Loehle In-Reply-To: <2zreguw4djctgcmvgticnm4dctcuja7yfnp3r6bxaqon3i2pxf@thee3p3qduoq> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit 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.