From patchwork Wed Feb 19 10:17:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sakari Ailus X-Patchwork-Id: 194410 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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 2449AC34047 for ; Wed, 19 Feb 2020 10:21:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 053F024658 for ; Wed, 19 Feb 2020 10:21:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726469AbgBSKV0 (ORCPT ); Wed, 19 Feb 2020 05:21:26 -0500 Received: from retiisi.org.uk ([95.216.213.190]:33598 "EHLO hillosipuli.retiisi.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726270AbgBSKV0 (ORCPT ); Wed, 19 Feb 2020 05:21:26 -0500 Received: from lanttu.localdomain (unknown [IPv6:2a01:4f9:c010:4572::e1:1001]) by hillosipuli.retiisi.org.uk (Postfix) with ESMTP id 667C5634C87; Wed, 19 Feb 2020 12:20:43 +0200 (EET) From: Sakari Ailus To: linux-acpi@vger.kernel.org Cc: rafael@kernel.org Subject: [PATCH 1/1] PM-runtime: Add pm_runtime_get_if_active Date: Wed, 19 Feb 2020 12:17:24 +0200 Message-Id: <20200219101724.27521-1-sakari.ailus@linux.intel.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org pm_runtime_get_if_in_use() bumps the usage count if the usage count is non-zero and the device's runtime PM status is active. This works for drivers that do not use autoidle, but for those that do, the function returns zero even when the device is active. In order to maintain sane device state while the device is powered on in hope it'll be needed, pm_runtime_get_if_active(dev, true) returns greater than zero if the device was in active state when it was called, in which case it also increments the device's usage_count. If the second argument of pm_runtime_get_if_active() is false, the function acts just as pm_runtime_get_if_in_use() does. This patch also makes the latter as a wrapper for the former. Signed-off-by: Sakari Ailus --- Documentation/power/runtime_pm.rst | 6 +++++ drivers/base/power/runtime.c | 36 ++++++++++++++++++++++-------- include/linux/pm_runtime.h | 12 +++++++++- 3 files changed, 44 insertions(+), 10 deletions(-) diff --git a/Documentation/power/runtime_pm.rst b/Documentation/power/runtime_pm.rst index ab8406c84254..0553008b6279 100644 --- a/Documentation/power/runtime_pm.rst +++ b/Documentation/power/runtime_pm.rst @@ -382,6 +382,12 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: nonzero, increment the counter and return 1; otherwise return 0 without changing the counter + `int pm_runtime_get_if_active(struct device *dev, bool ign_usage_count);` + - return -EINVAL if 'power.disable_depth' is nonzero; otherwise, if the + runtime PM status is RPM_ACTIVE, and either ign_usage_count is true + or the device's usage_count is non-zero, increment the counter and + return 1; otherwise return 0 without changing the counter + `void pm_runtime_put_noidle(struct device *dev);` - decrement the device's usage counter diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 16134a69bf6f..99c7da112c95 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -1087,29 +1087,47 @@ int __pm_runtime_resume(struct device *dev, int rpmflags) EXPORT_SYMBOL_GPL(__pm_runtime_resume); /** - * pm_runtime_get_if_in_use - Conditionally bump up the device's usage counter. + * pm_runtime_get_if_active - Conditionally bump up the device's usage counter. * @dev: Device to handle. * * Return -EINVAL if runtime PM is disabled for the device. * - * If that's not the case and if the device's runtime PM status is RPM_ACTIVE - * and the runtime PM usage counter is nonzero, increment the counter and - * return 1. Otherwise return 0 without changing the counter. + * Otherwise, if the device's runtime PM status is RPM_ACTIVE and either + * ign_usage_count is true or the device's usage_count is non-zero, increment + * the counter and return 1. Otherwise return 0 without changing the counter. + * + * If ign_usage_count is true, the function can be used to prevent suspending + * the device when its runtime PM status is RPM_ACTIVE. + * + * If ign_usage_count is false, the function can be used to prevent suspending + * the device when both its runtime PM status is RPM_ACTIVE and its usage_count + * is non-zero. + * + * The caller is resposible for putting the device's usage count when ther + * return value is greater than zero. */ -int pm_runtime_get_if_in_use(struct device *dev) +int pm_runtime_get_if_active(struct device *dev, bool ign_usage_count) { unsigned long flags; int retval; spin_lock_irqsave(&dev->power.lock, flags); - retval = dev->power.disable_depth > 0 ? -EINVAL : - dev->power.runtime_status == RPM_ACTIVE - && atomic_inc_not_zero(&dev->power.usage_count); + if (dev->power.disable_depth > 0) { + retval = -EINVAL; + } else if (dev->power.runtime_status != RPM_ACTIVE) { + retval = 0; + } else if (ign_usage_count) { + retval = 1; + atomic_inc(&dev->power.usage_count); + } else { + retval = atomic_inc_not_zero(&dev->power.usage_count); + } trace_rpm_usage_rcuidle(dev, 0); spin_unlock_irqrestore(&dev->power.lock, flags); + return retval; } -EXPORT_SYMBOL_GPL(pm_runtime_get_if_in_use); +EXPORT_SYMBOL_GPL(pm_runtime_get_if_active); /** * __pm_runtime_set_status - Set runtime PM status of a device. diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h index 22af69d237a6..3bdcbce8141a 100644 --- a/include/linux/pm_runtime.h +++ b/include/linux/pm_runtime.h @@ -38,7 +38,7 @@ extern int pm_runtime_force_resume(struct device *dev); extern int __pm_runtime_idle(struct device *dev, int rpmflags); extern int __pm_runtime_suspend(struct device *dev, int rpmflags); extern int __pm_runtime_resume(struct device *dev, int rpmflags); -extern int pm_runtime_get_if_in_use(struct device *dev); +extern int pm_runtime_get_if_active(struct device *dev, bool ign_usage_count); extern int pm_schedule_suspend(struct device *dev, unsigned int delay); extern int __pm_runtime_set_status(struct device *dev, unsigned int status); extern int pm_runtime_barrier(struct device *dev); @@ -60,6 +60,11 @@ extern void pm_runtime_put_suppliers(struct device *dev); extern void pm_runtime_new_link(struct device *dev); extern void pm_runtime_drop_link(struct device *dev); +static inline int pm_runtime_get_if_in_use(struct device *dev) +{ + return pm_runtime_get_if_active(dev, false); +} + static inline void pm_suspend_ignore_children(struct device *dev, bool enable) { dev->power.ignore_children = enable; @@ -143,6 +148,11 @@ static inline int pm_runtime_get_if_in_use(struct device *dev) { return -EINVAL; } +static inline int pm_runtime_get_if_active(struct device *dev, + bool ign_usage_count) +{ + return -EINVAL; +} static inline int __pm_runtime_set_status(struct device *dev, unsigned int status) { return 0; } static inline int pm_runtime_barrier(struct device *dev) { return 0; }