From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from canpmsgout01.his.huawei.com (canpmsgout01.his.huawei.com [113.46.200.216]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 29F2739B4BC; Tue, 17 Mar 2026 08:42:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=113.46.200.216 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773736970; cv=none; b=s6X05JRNmRIAcBqbOSy92+1CNirB4ZKOtnom//zDEeagN0u0eO6oiQYRdfpiw7LKHuBAfX64vCfZtwuyhp4lm0XkHivlfFPcSfmmydOeiUw+xFQ/vxStLzVZd/DvqwLQNRjlPhYAydRSFgUcxhGrxmpt928J6d1Vpr8PybUNTQo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773736970; c=relaxed/simple; bh=39i0FKvjbnLo0UcB1HUzCVNIP0REpjbkijj1jKEeZKs=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=ElB2D6wyHs4yJFVxcXPfI5JcFAQHvgf9TuGyAos8fcNil58k2P3RWkjd0IzVBELCKIPUMeeRh3ZmAA95rVD819TR2uCbPwTtcznTA0fJZqBX+x7HE6A968XwzP9hMKCM8EWAJA4Vu8D4wqgrduyVTIAdx2yBM0oataKTI5rmQ3w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b=Ggz+E/xp; arc=none smtp.client-ip=113.46.200.216 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b="Ggz+E/xp" dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=TnIUpYSoUJH43ZHFR5aKdHD8AMHQO6zFXhEONnGc1d4=; b=Ggz+E/xpQrytBBwhFN28wbfvZfu3Hb+ZF7efQvSxMVjHbla7VLAnZb0DFFl/5qMYj4BGuJVI+ E+nTjnbsw+Fv9L9BWfeb519SJH15zeN1sTe/VouLH07HaXupEMdBvJBZW1gEMK+oVz6PruAxgjk GIe6a52knXH29CkElz+jAfk= Received: from mail.maildlp.com (unknown [172.19.162.144]) by canpmsgout01.his.huawei.com (SkyGuard) with ESMTPS id 4fZlh40MgQz1T4GV; Tue, 17 Mar 2026 16:37:24 +0800 (CST) Received: from kwepemf200001.china.huawei.com (unknown [7.202.181.227]) by mail.maildlp.com (Postfix) with ESMTPS id CE50340567; Tue, 17 Mar 2026 16:42:43 +0800 (CST) Received: from [10.67.121.90] (10.67.121.90) by kwepemf200001.china.huawei.com (7.202.181.227) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Tue, 17 Mar 2026 16:42:43 +0800 Message-ID: <4c1bec09-4a13-4bbb-a0a5-0014157c3297@huawei.com> Date: Tue, 17 Mar 2026 16:42:42 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 1/6] cpufreq: Remove per-CPU QoS constraint To: Pierre Gondois , Viresh Kumar CC: , Jie Zhan , Ionela Voinescu , Sumit Gupta , Christian Loehle , "Rafael J. Wysocki" , Huang Rui , "Gautham R. Shenoy" , Mario Limonciello , Perry Yuan , Srinivas Pandruvada , Len Brown , Saravana Kannan , References: <20260225084930.1692228-1-pierre.gondois@arm.com> <20260225084930.1692228-2-pierre.gondois@arm.com> From: "zhenglifeng (A)" In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-ClientProxiedBy: kwepems200002.china.huawei.com (7.221.188.68) To kwepemf200001.china.huawei.com (7.202.181.227) On 3/16/2026 10:45 PM, Pierre Gondois wrote: > > On 3/13/26 09:57, Viresh Kumar wrote: >> On 25-02-26, 09:49, Pierre Gondois wrote: >>> policy->max_freq_req represents the maximum allowed frequency as >>> requested by the policyX/scaling_max_freq sysfs file. This request >>> applies to all CPUs of the policy. It is not possible to request >>> a per-CPU maximum frequency. >>> >>> Thus, the interaction between the policy boost and scaling_max_freq >>> settings should be handled by adding a boost specific QoS constraint. >>> This will be handled in the following patches. >>> >>> This patch reverts of: >>> commit 1608f0230510 ("cpufreq: Fix re-boost issue after hotplugging >>> a CPU") >>> >>> Reviewed-by: Lifeng Zheng >>> Signed-off-by: Pierre Gondois >>> --- >>>   drivers/cpufreq/cpufreq.c | 4 ---- >>>   1 file changed, 4 deletions(-) >>> >>> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c >>> index 4472bb1ec83c7..db414c052658b 100644 >>> --- a/drivers/cpufreq/cpufreq.c >>> +++ b/drivers/cpufreq/cpufreq.c >>> @@ -1481,10 +1481,6 @@ static int cpufreq_policy_online(struct cpufreq_policy *policy, >>>             blocking_notifier_call_chain(&cpufreq_policy_notifier_list, >>>                   CPUFREQ_CREATE_POLICY, policy); >>> -    } else { >>> -        ret = freq_qos_update_request(policy->max_freq_req, policy->max); >>> -        if (ret < 0) >>> -            goto out_destroy_policy; >>>       } >>>         if (cpufreq_driver->get && has_target()) { >> Even if this change is required, I don't think this should be applied >> separately. Just reverting this will get the bug back, which was fixed by >> commit 1608f0230510. Individual patches shouldn't break kernel (and bisect) as >> much as possible. >> > I could not reproduce the original issue. > > At the time of the patch and still now, calls to > freq_qos_update_request() are checked against negative values. > The only exception is when using the scaling_max_frequency sysfs > entry, but this is out of the scope. > > So I don't see how: > > commit 1608f0230510 ("cpufreq: Fix re-boost issue after hotplugging a CPU") > > can prevent a CPU to reach the boost frequency.  The only path that > could fail and that I could reproduce was fixed by: > > https://lore.kernel.org/all/852ff11c589e6300730d207baac195b2d9d8b95f.1745511526.git.viresh.kumar@linaro.org/ > > So the current conclusion is that "cpufreq: Fix re-boost issue after hotplugging a CPU" > was not the real fix > > Yes. After Viresh's patchset, the original issue was solved. So commit 1608f0230510 is not needed anymore and can be reverted.