From patchwork Thu Apr 22 11:43:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukasz Luba X-Patchwork-Id: 12218309 X-Patchwork-Delegate: daniel.lezcano@linaro.org 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 ECC2AC43461 for ; Thu, 22 Apr 2021 11:43:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B552F6145F for ; Thu, 22 Apr 2021 11:43:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236152AbhDVLnx (ORCPT ); Thu, 22 Apr 2021 07:43:53 -0400 Received: from foss.arm.com ([217.140.110.172]:50416 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236139AbhDVLnw (ORCPT ); Thu, 22 Apr 2021 07:43:52 -0400 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 0FB8D1424; Thu, 22 Apr 2021 04:43:18 -0700 (PDT) Received: from e123648.arm.com (unknown [10.57.27.187]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 7A32B3F774; Thu, 22 Apr 2021 04:43:16 -0700 (PDT) From: Lukasz Luba To: linux-kernel@vger.kernel.org, daniel.lezcano@linaro.org Cc: linux-pm@vger.kernel.org, amitk@kernel.org, rui.zhang@intel.com, lukasz.luba@arm.com Subject: [PATCH v4 1/3] thermal: create a helper __thermal_cdev_update() without a lock Date: Thu, 22 Apr 2021 12:43:06 +0100 Message-Id: <20210422114308.29684-2-lukasz.luba@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210422114308.29684-1-lukasz.luba@arm.com> References: <20210422114308.29684-1-lukasz.luba@arm.com> Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org There is a need to have a helper function which updates cooling device state from the governors code. With this change governor can use lock and unlock while calling helper function. This avoid unnecessary second time lock/unlock which was in previous solution present in governor implementation. This new helper function must be called with mutex 'cdev->lock' hold. The changed been discussed and part of code presented in thread: https://lore.kernel.org/linux-pm/20210419084536.25000-1-lukasz.luba@arm.com/ Co-developed-by: Daniel Lezcano Signed-off-by: Daniel Lezcano Signed-off-by: Lukasz Luba --- drivers/thermal/thermal_core.h | 1 + drivers/thermal/thermal_helpers.c | 27 +++++++++++++++++---------- 2 files changed, 18 insertions(+), 10 deletions(-) diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h index 86b8cef7310e..726e327b4205 100644 --- a/drivers/thermal/thermal_core.h +++ b/drivers/thermal/thermal_core.h @@ -66,6 +66,7 @@ static inline bool cdev_is_power_actor(struct thermal_cooling_device *cdev) } void thermal_cdev_update(struct thermal_cooling_device *); +void __thermal_cdev_update(struct thermal_cooling_device *cdev); /** * struct thermal_trip - representation of a point in temperature domain diff --git a/drivers/thermal/thermal_helpers.c b/drivers/thermal/thermal_helpers.c index 7f50f412e02a..3edd047e144f 100644 --- a/drivers/thermal/thermal_helpers.c +++ b/drivers/thermal/thermal_helpers.c @@ -192,18 +192,11 @@ static void thermal_cdev_set_cur_state(struct thermal_cooling_device *cdev, thermal_cooling_device_stats_update(cdev, target); } -void thermal_cdev_update(struct thermal_cooling_device *cdev) +void __thermal_cdev_update(struct thermal_cooling_device *cdev) { struct thermal_instance *instance; unsigned long target = 0; - mutex_lock(&cdev->lock); - /* cooling device is updated*/ - if (cdev->updated) { - mutex_unlock(&cdev->lock); - return; - } - /* Make sure cdev enters the deepest cooling state */ list_for_each_entry(instance, &cdev->thermal_instances, cdev_node) { dev_dbg(&cdev->device, "zone%d->target=%lu\n", @@ -216,11 +209,25 @@ void thermal_cdev_update(struct thermal_cooling_device *cdev) thermal_cdev_set_cur_state(cdev, target); - cdev->updated = true; - mutex_unlock(&cdev->lock); trace_cdev_update(cdev, target); dev_dbg(&cdev->device, "set to state %lu\n", target); } + +/** + * thermal_cdev_update - update cooling device state if needed + * @cdev: pointer to struct thermal_cooling_device + * + * Update the cooling device state if there is a need. + */ +void thermal_cdev_update(struct thermal_cooling_device *cdev) +{ + mutex_lock(&cdev->lock); + if (!cdev->updated) { + __thermal_cdev_update(cdev); + cdev->updated = true; + } + mutex_unlock(&cdev->lock); +} EXPORT_SYMBOL(thermal_cdev_update); /**