From patchwork Wed Jul 19 13:05:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xuewen Yan X-Patchwork-Id: 706044 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B91D8C001B0 for ; Wed, 19 Jul 2023 13:07:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230477AbjGSNHP (ORCPT ); Wed, 19 Jul 2023 09:07:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41036 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230041AbjGSNHO (ORCPT ); Wed, 19 Jul 2023 09:07:14 -0400 Received: from SHSQR01.spreadtrum.com (unknown [222.66.158.135]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3B9841A6 for ; Wed, 19 Jul 2023 06:07:12 -0700 (PDT) Received: from dlp.unisoc.com ([10.29.3.86]) by SHSQR01.spreadtrum.com with ESMTP id 36JD5Zqj043653; Wed, 19 Jul 2023 21:05:35 +0800 (+08) (envelope-from Xuewen.Yan@unisoc.com) Received: from SHDLP.spreadtrum.com (bjmbx01.spreadtrum.com [10.0.64.7]) by dlp.unisoc.com (SkyGuard) with ESMTPS id 4R5bch0SXJz2K1r9p; Wed, 19 Jul 2023 21:04:20 +0800 (CST) Received: from BJ10918NBW01.spreadtrum.com (10.0.73.72) by BJMBX01.spreadtrum.com (10.0.64.7) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Wed, 19 Jul 2023 21:05:33 +0800 From: Xuewen Yan To: , , , , CC: , , , , , , , , , Subject: [PATCH] cpufreq: schedutil: next_freq need update when cpufreq_limits changed Date: Wed, 19 Jul 2023 21:05:27 +0800 Message-ID: <20230719130527.8074-1-xuewen.yan@unisoc.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Originating-IP: [10.0.73.72] X-ClientProxiedBy: SHCAS03.spreadtrum.com (10.0.1.207) To BJMBX01.spreadtrum.com (10.0.64.7) X-MAIL: SHSQR01.spreadtrum.com 36JD5Zqj043653 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org When cpufreq's policy is single, there is a scenario that will cause sg_policy's next_freq to be unable to update. When the cpu's util is always max, the cpufreq will be max, and then if we change the policy's scaling_max_freq to be a lower freq, indeed, the sg_policy's next_freq need change to be the lower freq, however, because the cpu_is_busy, the next_freq would keep the max_freq. For example: The cpu7 is single cpu: unisoc:/sys/devices/system/cpu/cpufreq/policy7 # while true;do done& [1] 4737 unisoc:/sys/devices/system/cpu/cpufreq/policy7 # taskset -p 80 4737 pid 4737's current affinity mask: ff pid 4737's new affinity mask: 80 unisoc:/sys/devices/system/cpu/cpufreq/policy7 # cat scaling_max_freq 2301000 unisoc:/sys/devices/system/cpu/cpufreq/policy7 # cat scaling_cur_freq 2301000 unisoc:/sys/devices/system/cpu/cpufreq/policy7 # echo 2171000 > scaling_max_freq unisoc:/sys/devices/system/cpu/cpufreq/policy7 # cat scaling_max_freq 2171000 At this time, the sg_policy's next_freq would keep 2301000. To prevent the case happen, add the judgment of the need_freq_update flag. Signed-off-by: Xuewen Yan Co-developed-by: Guohua Yan Signed-off-by: Guohua Yan --- kernel/sched/cpufreq_schedutil.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index 4492608b7d7f..458d359f5991 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -350,7 +350,8 @@ static void sugov_update_single_freq(struct update_util_data *hook, u64 time, * Except when the rq is capped by uclamp_max. */ if (!uclamp_rq_is_capped(cpu_rq(sg_cpu->cpu)) && - sugov_cpu_is_busy(sg_cpu) && next_f < sg_policy->next_freq) { + sugov_cpu_is_busy(sg_cpu) && next_f < sg_policy->next_freq && + !sg_policy->need_freq_update) { next_f = sg_policy->next_freq; /* Restore cached freq as next_freq has changed */