From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C79ECC35247 for ; Mon, 3 Feb 2020 23:14:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 90FF020721 for ; Mon, 3 Feb 2020 23:14:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726474AbgBCXOg (ORCPT ); Mon, 3 Feb 2020 18:14:36 -0500 Received: from cloudserver094114.home.pl ([79.96.170.134]:63218 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726369AbgBCXOg (ORCPT ); Mon, 3 Feb 2020 18:14:36 -0500 Received: from 79.184.253.222.ipv4.supernova.orange.pl (79.184.253.222) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.341) id 200205067b441903; Tue, 4 Feb 2020 00:14:33 +0100 From: "Rafael J. Wysocki" To: Linux PM Cc: LKML Subject: [PATCH] cpuidle: Documentation: Clean up PM QoS description Date: Tue, 04 Feb 2020 00:14:33 +0100 Message-ID: <2508205.dfSqNlTTCn@kreacher> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Rafael J. Wysocki Clean up the language in one paragraph in the PM QoS description in Documentation/admin-guide/pm/cpuidle.rst. Signed-off-by: Rafael J. Wysocki --- Documentation/admin-guide/pm/cpuidle.rst | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) Index: linux-pm/Documentation/admin-guide/pm/cpuidle.rst =================================================================== --- linux-pm.orig/Documentation/admin-guide/pm/cpuidle.rst +++ linux-pm/Documentation/admin-guide/pm/cpuidle.rst @@ -632,16 +632,16 @@ class priority list and destroyed. If t will be used, again, to determine the new effective value for the whole list and that value will become the new real constraint. -In turn, for each CPU there is only one resume latency PM QoS request -associated with the :file:`power/pm_qos_resume_latency_us` file under +In turn, for each CPU there is one resume latency PM QoS request associated with +the :file:`power/pm_qos_resume_latency_us` file under :file:`/sys/devices/system/cpu/cpu/` in ``sysfs`` and writing to it causes this single PM QoS request to be updated regardless of which user space process does that. In other words, this PM QoS request is shared by the entire user space, so access to the file associated with it needs to be arbitrated to avoid confusion. [Arguably, the only legitimate use of this mechanism in practice is to pin a process to the CPU in question and let it use the -``sysfs`` interface to control the resume latency constraint for it.] It -still only is a request, however. It is a member of a priority list used to +``sysfs`` interface to control the resume latency constraint for it.] It is +still only a request, however. It is an entry in a priority list used to determine the effective value to be set as the resume latency constraint for the CPU in question every time the list of requests is updated this way or another (there may be other requests coming from kernel code in that list).