From patchwork Tue Mar 23 07:20:10 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aisheng Dong X-Patchwork-Id: 407253 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 5EF50C433E2 for ; Tue, 23 Mar 2021 07:35:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 33E19619CF for ; Tue, 23 Mar 2021 07:35:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229822AbhCWHe2 (ORCPT ); Tue, 23 Mar 2021 03:34:28 -0400 Received: from inva020.nxp.com ([92.121.34.13]:38636 "EHLO inva020.nxp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229508AbhCWHd6 (ORCPT ); Tue, 23 Mar 2021 03:33:58 -0400 Received: from inva020.nxp.com (localhost [127.0.0.1]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 114F61A1D04; Tue, 23 Mar 2021 08:33:55 +0100 (CET) Received: from invc005.ap-rdc01.nxp.com (invc005.ap-rdc01.nxp.com [165.114.16.14]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 50E221A1D09; Tue, 23 Mar 2021 08:33:50 +0100 (CET) Received: from localhost.localdomain (shlinux2.ap.freescale.net [10.192.224.44]) by invc005.ap-rdc01.nxp.com (Postfix) with ESMTP id 8376A402AC; Tue, 23 Mar 2021 08:33:44 +0100 (CET) From: Dong Aisheng To: linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: dongas86@gmail.com, kernel@pengutronix.de, shawnguo@kernel.org, linux-imx@nxp.com, linux-kernel@vger.kernel.org, myungjoo.ham@samsung.com, kyungmin.park@samsung.com, cw00.choi@samsung.com, abel.vesa@nxp.com, Dong Aisheng Subject: [PATCH V2 RESEND 3/4] PM / devfreq: bail out early if no freq changes in devfreq_set_target Date: Tue, 23 Mar 2021 15:20:10 +0800 Message-Id: <1616484011-26702-4-git-send-email-aisheng.dong@nxp.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1616484011-26702-1-git-send-email-aisheng.dong@nxp.com> References: <1616484011-26702-1-git-send-email-aisheng.dong@nxp.com> X-Virus-Scanned: ClamAV using ClamSMTP Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org It's unnecessary to set the same freq again and run notifier calls. Signed-off-by: Dong Aisheng --- drivers/devfreq/devfreq.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 85927bd7ee76..a6ee91dd17bd 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -352,13 +352,16 @@ static int devfreq_set_target(struct devfreq *devfreq, unsigned long new_freq, { struct devfreq_freqs freqs; unsigned long cur_freq; - int err = 0; + int err; if (devfreq->profile->get_cur_freq) devfreq->profile->get_cur_freq(devfreq->dev.parent, &cur_freq); else cur_freq = devfreq->previous_freq; + if (new_freq == cur_freq) + return 0; + freqs.old = cur_freq; freqs.new = new_freq; devfreq_notify_transition(devfreq, &freqs, DEVFREQ_PRECHANGE); @@ -375,7 +378,7 @@ static int devfreq_set_target(struct devfreq *devfreq, unsigned long new_freq, * and DEVFREQ_POSTCHANGE because for showing the correct frequency * change order of between devfreq device and passive devfreq device. */ - if (trace_devfreq_frequency_enabled() && new_freq != cur_freq) + if (trace_devfreq_frequency_enabled()) trace_devfreq_frequency(devfreq, new_freq, cur_freq); freqs.new = new_freq; @@ -390,7 +393,7 @@ static int devfreq_set_target(struct devfreq *devfreq, unsigned long new_freq, if (devfreq->suspend_freq) devfreq->resume_freq = new_freq; - return err; + return 0; } /**