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: 12157085 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=-17.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,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 E7F4DC433DB for ; Tue, 23 Mar 2021 07:36:07 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6E1EE619B7 for ; Tue, 23 Mar 2021 07:36:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6E1EE619B7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=nxp.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:MIME-Version:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:References:In-Reply-To:Message-Id:Date:Subject:Cc:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=TGFwD0xvwv2LnA/N/jDYOKQH3bsP6FrZpnXcZ3599vI=; b=bmd3l2YeB9saIeVDg5bVSmiEbT KTKv+gPqYaejzbW0cS7Ob3Fy3scV0lC77WQbR8/gu2KTBROVy81ugfAG5Y8Z17636x5oxirfsRamE Qm5Zv5HFkYWp/2BVefPpJ22kmpjr0KmgVyGY4TR2vREiWCLqIfofxxU2gYUoUm3nmrPFOr0SY2ZZ3 8nrtEF6L1Nq11+YVPLvqanxAEMwULwAYCrRby/eVDCADO8pmzOcS+GmmHxsUxoErN704gjlo6bltw IQRTQwLAxCzPtFkf6A8Ec6GLOwgz6SotFw6YoE9XC/4Qy8JhlSXFPsNar7CG6sCrb7Yr2DDHxvIZL tj/Ji53g==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lObYg-00E9pK-JV; Tue, 23 Mar 2021 07:34:35 +0000 Received: from inva020.nxp.com ([92.121.34.13]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lObY3-00E9bU-Go for linux-arm-kernel@lists.infradead.org; Tue, 23 Mar 2021 07:33:57 +0000 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210323_073355_832071_FF0B0602 X-CRM114-Status: GOOD ( 11.95 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.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; } /**