From patchwork Tue Mar 9 12:58:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aisheng Dong X-Patchwork-Id: 397104 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 5C8B2C1550B for ; Tue, 9 Mar 2021 13:13:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0D7AD65274 for ; Tue, 9 Mar 2021 13:13:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231335AbhCINNB (ORCPT ); Tue, 9 Mar 2021 08:13:01 -0500 Received: from inva020.nxp.com ([92.121.34.13]:47504 "EHLO inva020.nxp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230503AbhCINMv (ORCPT ); Tue, 9 Mar 2021 08:12:51 -0500 Received: from inva020.nxp.com (localhost [127.0.0.1]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id D92D31A1009; Tue, 9 Mar 2021 14:12:49 +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 7976F1A1011; Tue, 9 Mar 2021 14:12:43 +0100 (CET) Received: from localhost.localdomain (shlinux2.ap.freescale.net [10.192.224.44]) by invc005.ap-rdc01.nxp.com (Postfix) with ESMTP id EEED7402A7; Tue, 9 Mar 2021 14:12:35 +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 09/11] PM / devfreq: governor: optimize simpleondemand get_target_freq Date: Tue, 9 Mar 2021 20:58:51 +0800 Message-Id: <1615294733-22761-22-git-send-email-aisheng.dong@nxp.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1615294733-22761-1-git-send-email-aisheng.dong@nxp.com> References: <1615294733-22761-1-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 devfreq_simple_ondemand_data only needs to be initialized once when calling devm_devfreq_add_device. It's unnecessary to put the data check logic in the hot path (.get_target_freq()) where it will be called all the time during polling. Instead, we only check and initialize it one time during DEVFREQ_GOV_START. This also helps check data validability in advance during DEVFREQ_GOV_START rather than checking it later when running .get_target_freq(). Signed-off-by: Dong Aisheng --- drivers/devfreq/governor_simpleondemand.c | 50 +++++++++++++++-------- 1 file changed, 34 insertions(+), 16 deletions(-) diff --git a/drivers/devfreq/governor_simpleondemand.c b/drivers/devfreq/governor_simpleondemand.c index ea287b57cbf3..341eb7e9dc04 100644 --- a/drivers/devfreq/governor_simpleondemand.c +++ b/drivers/devfreq/governor_simpleondemand.c @@ -15,15 +15,19 @@ /* Default constants for DevFreq-Simple-Ondemand (DFSO) */ #define DFSO_UPTHRESHOLD (90) #define DFSO_DOWNDIFFERENCTIAL (5) + +static struct devfreq_simple_ondemand_data od_default = { + .upthreshold = DFSO_UPTHRESHOLD, + .downdifferential = DFSO_DOWNDIFFERENCTIAL, +}; + static int devfreq_simple_ondemand_func(struct devfreq *df, unsigned long *freq) { int err; struct devfreq_dev_status *stat; unsigned long long a, b; - unsigned int dfso_upthreshold = DFSO_UPTHRESHOLD; - unsigned int dfso_downdifferential = DFSO_DOWNDIFFERENCTIAL; - struct devfreq_simple_ondemand_data *data = df->data; + struct devfreq_simple_ondemand_data *od = df->data; err = devfreq_update_stats(df); if (err) @@ -31,16 +35,6 @@ static int devfreq_simple_ondemand_func(struct devfreq *df, stat = &df->last_status; - if (data) { - if (data->upthreshold) - dfso_upthreshold = data->upthreshold; - if (data->downdifferential) - dfso_downdifferential = data->downdifferential; - } - if (dfso_upthreshold > 100 || - dfso_upthreshold < dfso_downdifferential) - return -EINVAL; - /* Assume MAX if it is going to be divided by zero */ if (stat->total_time == 0) { *freq = DEVFREQ_MAX_FREQ; @@ -55,7 +49,7 @@ static int devfreq_simple_ondemand_func(struct devfreq *df, /* Set MAX if it's busy enough */ if (stat->busy_time * 100 > - stat->total_time * dfso_upthreshold) { + stat->total_time * od->upthreshold) { *freq = DEVFREQ_MAX_FREQ; return 0; } @@ -68,7 +62,7 @@ static int devfreq_simple_ondemand_func(struct devfreq *df, /* Keep the current frequency */ if (stat->busy_time * 100 > - stat->total_time * (dfso_upthreshold - dfso_downdifferential)) { + stat->total_time * (od->upthreshold - od->downdifferential)) { *freq = stat->current_frequency; return 0; } @@ -78,17 +72,41 @@ static int devfreq_simple_ondemand_func(struct devfreq *df, a *= stat->current_frequency; b = div_u64(a, stat->total_time); b *= 100; - b = div_u64(b, (dfso_upthreshold - dfso_downdifferential / 2)); + b = div_u64(b, (od->upthreshold - od->downdifferential / 2)); *freq = (unsigned long) b; return 0; } +static int devfreq_simple_ondemand_check_od(struct devfreq *devfreq) +{ + struct devfreq_simple_ondemand_data *od = devfreq->data; + + if (od) { + if (!od->upthreshold) + od->upthreshold = DFSO_UPTHRESHOLD; + + if (!od->downdifferential) + od->downdifferential = DFSO_DOWNDIFFERENCTIAL; + + if (od->upthreshold > 100 || + od->upthreshold < od->downdifferential) + return -EINVAL; + } else { + od = &od_default; + } + + return 0; +} + static int devfreq_simple_ondemand_handler(struct devfreq *devfreq, unsigned int event, void *data) { switch (event) { case DEVFREQ_GOV_START: + if (devfreq_simple_ondemand_check_od(devfreq)) + return -EINVAL; + return devfreq_monitor_start(devfreq); case DEVFREQ_GOV_STOP: