From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ulf Hansson Subject: [PATCH 3/4] PM / Domains: Search for the CPU device outside the genpd lock Date: Thu, 25 Apr 2019 11:04:12 +0200 Message-ID: <20190425090413.10700-4-ulf.hansson@linaro.org> References: <20190425090413.10700-1-ulf.hansson@linaro.org> Return-path: In-Reply-To: <20190425090413.10700-1-ulf.hansson@linaro.org> Sender: linux-kernel-owner@vger.kernel.org To: "Rafael J . Wysocki" , linux-pm@vger.kernel.org Cc: Ulf Hansson , Daniel Lezcano , "Raju P . L . S . S . S . N" , Stephen Boyd , Tony Lindgren , Kevin Hilman , Lina Iyer , Rajendra Nayak , Viresh Kumar , Niklas Cassel , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: linux-pm@vger.kernel.org While attaching/detaching a device to a PM domain (genpd) that has the GENPD_FLAG_CPU_DOMAIN set, genpd iterates the cpu_possible_mask to check whether the device corresponds to a CPU. This iteration is done while holding the genpd's lock, which is unnecessary. Let's avoid the locking, by restructuring the corresponding code a bit. Signed-off-by: Ulf Hansson --- drivers/base/power/domain.c | 52 +++++++++++++++++++------------------ 1 file changed, 27 insertions(+), 25 deletions(-) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 93298b7db408..da1c99178943 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1450,8 +1450,8 @@ static void genpd_free_dev_data(struct device *dev, dev_pm_put_subsys_data(dev); } -static void __genpd_update_cpumask(struct generic_pm_domain *genpd, - int cpu, bool set, unsigned int depth) +static void genpd_update_cpumask(struct generic_pm_domain *genpd, + int cpu, bool set, unsigned int depth) { struct gpd_link *link; @@ -1462,7 +1462,7 @@ static void __genpd_update_cpumask(struct generic_pm_domain *genpd, struct generic_pm_domain *master = link->master; genpd_lock_nested(master, depth + 1); - __genpd_update_cpumask(master, cpu, set, depth + 1); + genpd_update_cpumask(master, cpu, set, depth + 1); genpd_unlock(master); } @@ -1472,38 +1472,37 @@ static void __genpd_update_cpumask(struct generic_pm_domain *genpd, cpumask_clear_cpu(cpu, genpd->cpus); } -static void genpd_update_cpumask(struct generic_pm_domain *genpd, - struct device *dev, bool set) +static void genpd_set_cpumask(struct generic_pm_domain *genpd, int cpu) +{ + if (cpu >= 0) + genpd_update_cpumask(genpd, cpu, true, 0); +} + +static void genpd_clear_cpumask(struct generic_pm_domain *genpd, int cpu) +{ + if (cpu >= 0) + genpd_update_cpumask(genpd, cpu, false, 0); +} + +static int genpd_get_cpu(struct generic_pm_domain *genpd, struct device *dev) { int cpu; if (!genpd_is_cpu_domain(genpd)) - return; + return -1; for_each_possible_cpu(cpu) { - if (get_cpu_device(cpu) == dev) { - __genpd_update_cpumask(genpd, cpu, set, 0); - return; - } + if (get_cpu_device(cpu) == dev) + return cpu; } -} -static void genpd_set_cpumask(struct generic_pm_domain *genpd, - struct device *dev) -{ - genpd_update_cpumask(genpd, dev, true); -} - -static void genpd_clear_cpumask(struct generic_pm_domain *genpd, - struct device *dev) -{ - genpd_update_cpumask(genpd, dev, false); + return -1; } static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev) { struct generic_pm_domain_data *gpd_data; - int ret; + int ret, cpu; dev_dbg(dev, "%s()\n", __func__); @@ -1514,13 +1513,15 @@ static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev) if (IS_ERR(gpd_data)) return PTR_ERR(gpd_data); + cpu = genpd_get_cpu(genpd, dev); + ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0; if (ret) goto out; genpd_lock(genpd); - genpd_set_cpumask(genpd, dev); + genpd_set_cpumask(genpd, cpu); dev_pm_domain_set(dev, &genpd->domain); genpd->device_count++; @@ -1560,13 +1561,14 @@ static int genpd_remove_device(struct generic_pm_domain *genpd, { struct generic_pm_domain_data *gpd_data; struct pm_domain_data *pdd; - int ret = 0; + int cpu, ret = 0; dev_dbg(dev, "%s()\n", __func__); pdd = dev->power.subsys_data->domain_data; gpd_data = to_gpd_data(pdd); dev_pm_qos_remove_notifier(dev, &gpd_data->nb); + cpu = genpd_get_cpu(genpd, dev); genpd_lock(genpd); @@ -1578,7 +1580,7 @@ static int genpd_remove_device(struct generic_pm_domain *genpd, genpd->device_count--; genpd->max_off_time_changed = true; - genpd_clear_cpumask(genpd, dev); + genpd_clear_cpumask(genpd, cpu); dev_pm_domain_set(dev, NULL); list_del_init(&pdd->list_node); -- 2.17.1 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=-6.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNWANTED_LANGUAGE_BODY,USER_AGENT_GIT autolearn=unavailable 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 1C5EEC282E1 for ; Thu, 25 Apr 2019 09:04:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D6ECE214C6 for ; Thu, 25 Apr 2019 09:04:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="BAmUdz0A" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727940AbfDYJEh (ORCPT ); Thu, 25 Apr 2019 05:04:37 -0400 Received: from mail-lj1-f195.google.com ([209.85.208.195]:43970 "EHLO mail-lj1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727887AbfDYJEg (ORCPT ); Thu, 25 Apr 2019 05:04:36 -0400 Received: by mail-lj1-f195.google.com with SMTP id k2so5288475lje.10 for ; Thu, 25 Apr 2019 02:04:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=ljpH5vhDYU6UY/Q2jNUSgYZIZdDGjQoptAffM3+XQlk=; b=BAmUdz0A6ucFtMa3FlMjlvWEkgHz+I/RgilH744my9IIg2l5Ut2yeVd499EqUNrr6R uV/4d0GC3qYyx6hCiI49R6RLU0kg/2hLato1gnweW5VdtAIm8JM2e0zrpFNRcFPidZnd h3/qVFeDrsxuCRCGoaPPavPlZpDY7b7UMRlMdiXQXYk9Zrw73S1i5lRTrrtbIRHkdGwb ewlfzjEnDEjEXq7oGTSkAonepLVdiQ/Hizm1tR0DDbGj44fhARuiSq0PIR7rFyEgI7JK klfi2i29i5xjhTfk+vEM6yAgeYBd690fWdvNX9Ybvab1BGCzhknbbmqCaB1iggqbLqWV FjvA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=ljpH5vhDYU6UY/Q2jNUSgYZIZdDGjQoptAffM3+XQlk=; b=JOFo2GRoZNcDNiTEjHI6S4pNfnyMTTLxdzakfalF8tXJNtjD/5gXgMGnkLYe//QNvr wFg6AkMsd9mBYJFmwWXwD3yabYGgwds7yyE0nuTK5PRv6pmR9/Jn2Ih+k+LYnbHtA05F CtvRpSrmJthbjYVL1Clj6lVSIYpz3lvp6zF0ZJVVfC7VTRL7xPFfxgY+O6TQdpF2EW4Y KkyoOrxLvJkwTmHoFN/eO1GI9J5RG8Z8Hrv9Ankb02r6ed/vAdmdx0xeD8enTb8bAbmj AbXoMoyEAaqZ7rwGLKj8BWtbT/j1V+ztn9zRKcrxuJZNb7WcNUKW0fw4fnKNG07I78e6 jIAQ== X-Gm-Message-State: APjAAAVQWzSST1VNOF+1W3Nw6CMVGse0pfZe8CnLR7QEffeBNmmS0FdA Xi7YosGCWk6PL97WP8AYKCbHcQ== X-Google-Smtp-Source: APXvYqwUgctYNY2PsII4FPHfAlMMLwytUkPcselJGfHLwIChpuih8ndC76NbC/2TMSVHxD4zsiSlAg== X-Received: by 2002:a2e:9a0f:: with SMTP id o15mr10280206lji.130.1556183073597; Thu, 25 Apr 2019 02:04:33 -0700 (PDT) Received: from localhost.localdomain (h-158-174-22-210.NA.cust.bahnhof.se. [158.174.22.210]) by smtp.gmail.com with ESMTPSA id v26sm4517353lja.60.2019.04.25.02.04.32 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 25 Apr 2019 02:04:32 -0700 (PDT) From: Ulf Hansson To: "Rafael J . Wysocki" , linux-pm@vger.kernel.org Cc: Ulf Hansson , Daniel Lezcano , "Raju P . L . S . S . S . N" , Stephen Boyd , Tony Lindgren , Kevin Hilman , Lina Iyer , Rajendra Nayak , Viresh Kumar , Niklas Cassel , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH 3/4] PM / Domains: Search for the CPU device outside the genpd lock Date: Thu, 25 Apr 2019 11:04:12 +0200 Message-Id: <20190425090413.10700-4-ulf.hansson@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190425090413.10700-1-ulf.hansson@linaro.org> References: <20190425090413.10700-1-ulf.hansson@linaro.org> Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Message-ID: <20190425090412.nqQ3-6HYW1GO3lxqpTFOSBH2gjqGoHDVHYHXznhvmis@z> While attaching/detaching a device to a PM domain (genpd) that has the GENPD_FLAG_CPU_DOMAIN set, genpd iterates the cpu_possible_mask to check whether the device corresponds to a CPU. This iteration is done while holding the genpd's lock, which is unnecessary. Let's avoid the locking, by restructuring the corresponding code a bit. Signed-off-by: Ulf Hansson --- drivers/base/power/domain.c | 52 +++++++++++++++++++------------------ 1 file changed, 27 insertions(+), 25 deletions(-) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 93298b7db408..da1c99178943 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1450,8 +1450,8 @@ static void genpd_free_dev_data(struct device *dev, dev_pm_put_subsys_data(dev); } -static void __genpd_update_cpumask(struct generic_pm_domain *genpd, - int cpu, bool set, unsigned int depth) +static void genpd_update_cpumask(struct generic_pm_domain *genpd, + int cpu, bool set, unsigned int depth) { struct gpd_link *link; @@ -1462,7 +1462,7 @@ static void __genpd_update_cpumask(struct generic_pm_domain *genpd, struct generic_pm_domain *master = link->master; genpd_lock_nested(master, depth + 1); - __genpd_update_cpumask(master, cpu, set, depth + 1); + genpd_update_cpumask(master, cpu, set, depth + 1); genpd_unlock(master); } @@ -1472,38 +1472,37 @@ static void __genpd_update_cpumask(struct generic_pm_domain *genpd, cpumask_clear_cpu(cpu, genpd->cpus); } -static void genpd_update_cpumask(struct generic_pm_domain *genpd, - struct device *dev, bool set) +static void genpd_set_cpumask(struct generic_pm_domain *genpd, int cpu) +{ + if (cpu >= 0) + genpd_update_cpumask(genpd, cpu, true, 0); +} + +static void genpd_clear_cpumask(struct generic_pm_domain *genpd, int cpu) +{ + if (cpu >= 0) + genpd_update_cpumask(genpd, cpu, false, 0); +} + +static int genpd_get_cpu(struct generic_pm_domain *genpd, struct device *dev) { int cpu; if (!genpd_is_cpu_domain(genpd)) - return; + return -1; for_each_possible_cpu(cpu) { - if (get_cpu_device(cpu) == dev) { - __genpd_update_cpumask(genpd, cpu, set, 0); - return; - } + if (get_cpu_device(cpu) == dev) + return cpu; } -} -static void genpd_set_cpumask(struct generic_pm_domain *genpd, - struct device *dev) -{ - genpd_update_cpumask(genpd, dev, true); -} - -static void genpd_clear_cpumask(struct generic_pm_domain *genpd, - struct device *dev) -{ - genpd_update_cpumask(genpd, dev, false); + return -1; } static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev) { struct generic_pm_domain_data *gpd_data; - int ret; + int ret, cpu; dev_dbg(dev, "%s()\n", __func__); @@ -1514,13 +1513,15 @@ static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev) if (IS_ERR(gpd_data)) return PTR_ERR(gpd_data); + cpu = genpd_get_cpu(genpd, dev); + ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0; if (ret) goto out; genpd_lock(genpd); - genpd_set_cpumask(genpd, dev); + genpd_set_cpumask(genpd, cpu); dev_pm_domain_set(dev, &genpd->domain); genpd->device_count++; @@ -1560,13 +1561,14 @@ static int genpd_remove_device(struct generic_pm_domain *genpd, { struct generic_pm_domain_data *gpd_data; struct pm_domain_data *pdd; - int ret = 0; + int cpu, ret = 0; dev_dbg(dev, "%s()\n", __func__); pdd = dev->power.subsys_data->domain_data; gpd_data = to_gpd_data(pdd); dev_pm_qos_remove_notifier(dev, &gpd_data->nb); + cpu = genpd_get_cpu(genpd, dev); genpd_lock(genpd); @@ -1578,7 +1580,7 @@ static int genpd_remove_device(struct generic_pm_domain *genpd, genpd->device_count--; genpd->max_off_time_changed = true; - genpd_clear_cpumask(genpd, dev); + genpd_clear_cpumask(genpd, cpu); dev_pm_domain_set(dev, NULL); list_del_init(&pdd->list_node); -- 2.17.1