From nobody Sat Sep 13 03:59:57 2025 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 2D728C636D4 for ; Sun, 5 Feb 2023 22:43:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229643AbjBEWnh (ORCPT ); Sun, 5 Feb 2023 17:43:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49890 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229559AbjBEWne (ORCPT ); Sun, 5 Feb 2023 17:43:34 -0500 Received: from mail-ej1-x62f.google.com (mail-ej1-x62f.google.com [IPv6:2a00:1450:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3F4171A48B for ; Sun, 5 Feb 2023 14:43:33 -0800 (PST) Received: by mail-ej1-x62f.google.com with SMTP id mc11so29413885ejb.10 for ; Sun, 05 Feb 2023 14:43:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=layalina-io.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=pIDKpUZt2NnF88laBIzE/5NEaQ9UqssI9HVNrkQhbgE=; b=BYL6g5q0EgU9yBxQf59pxMHrdp1oJDqgGJKpiH0qmaXrec/HizPz/+HDUzVpKPquzt jwPEksnWqxxjLC4BpeKg0GTRgY32ad/U4zL9/vWP6yA87pREBy9YG7b10bAdwo7bajFV mB6ZwqlT9bKrj1w37xQZbbc2C9zoEtmPu9L8akdb8BkhUBUXujw2ZcBeAG+NS9vEcNjD pA+FZU5Qe3xN7Mpa8SCiutAXaHs8wU38lo2XdQvmktH6q2GAbK90E2A3GtaQt+hk7SZ/ eFBSeiDwkHddL+oL7MH846vP1n+U/ZF16gijT9LVsyF+cVo5HkNbRkiX5Ke7dnKf3kSf O47g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=pIDKpUZt2NnF88laBIzE/5NEaQ9UqssI9HVNrkQhbgE=; b=UC3NrRwN1ALxr7viDtfDXMBz6tSocy6nPpeoY+naDUhZCgRQBTxNszmbGTJHQC3l1B b2/op3tGtEe7JntNm6nFSLD82XRIVk+F8/IZS8vkl3A5zl0wdYp+zIqPEMRItmXMj1dz EGAou4g5VbDbnFUaHcIOC41aqStpOefly1PDITYIh7sjT4SuwkbAa9Nd7+DoN9pUDjRT O7Eke84e1PijoPSRC0MS8wpaTmTDdzmlGgIWb55hE7RA+kUOL2M/DaFO/2YukTpbzp28 6GnfL+pEf9QB2tORDwPHGKwAwEAu/RVCv7ypKtlziGkYZ17ucRY9ewyZvCyxmXBx3CvZ bs/w== X-Gm-Message-State: AO0yUKXgx724NHWZEOgqCoR/t7AmVCaNDGBR9uI5zvaTy8sW/PkoH22l n4DZFUZWDu6PVEL1jJA/seygcg== X-Google-Smtp-Source: AK7set9y1BvEXoVnsbkqW7Qhol2b9EQ4LeeHNqIPWYhBRR54feDk029SEjVodxBpEatcFD/8XljLPQ== X-Received: by 2002:a17:907:3a97:b0:880:2870:7849 with SMTP id fh23-20020a1709073a9700b0088028707849mr13763626ejc.74.1675637011804; Sun, 05 Feb 2023 14:43:31 -0800 (PST) Received: from localhost.localdomain (host86-163-35-10.range86-163.btcentralplus.com. [86.163.35.10]) by smtp.gmail.com with ESMTPSA id m15-20020a1709061ecf00b0087bd2924e74sm4550779ejj.205.2023.02.05.14.43.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 05 Feb 2023 14:43:31 -0800 (PST) From: Qais Yousef To: Ingo Molnar , Peter Zijlstra , Vincent Guittot , Dietmar Eggemann Cc: linux-kernel@vger.kernel.org, Lukasz Luba , Wei Wang , Xuewen Yan , Hank , Jonathan JMChen , Qais Yousef Subject: [PATCH v2 1/3] sched/uclamp: Set max_spare_cap_cpu even if max_spare_cap is 0 Date: Sun, 5 Feb 2023 22:43:16 +0000 Message-Id: <20230205224318.2035646-2-qyousef@layalina.io> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230205224318.2035646-1-qyousef@layalina.io> References: <20230205224318.2035646-1-qyousef@layalina.io> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" When uclamp_max is being used, the util of the task could be higher than the spare capacity of the CPU, but due to uclamp_max value we force fit it there. The way the condition for checking for max_spare_cap in find_energy_efficient_cpu() was constructed; it ignored any CPU that has its spare_cap less than or _equal_ to max_spare_cap. Since we initialize max_spare_cap to 0; this lead to never setting max_spare_cap_cpu and hence ending up never performing compute_energy() for this cluster and missing an opportunity for a better energy efficient placement to honour uclamp_max setting. max_spare_cap =3D 0; cpu_cap =3D capacity_of(cpu) - task_util(p); // 0 if task_util(p) is high ... util_fits_cpu(...); // will return true if uclamp_max forces it to fit ... // this logic will fail to update max_spare_cap_cpu if cpu_cap is 0 if (cpu_cap > max_spare_cap) { max_spare_cap =3D cpu_cap; max_spare_cap_cpu =3D cpu; } prev_spare_cap suffers from a similar problem. Fix the logic by converting the variables into long and treating -1 value as 'not populated' instead of 0 which is a viable and correct spare capacity value. Fixes: 1d42509e475c ("sched/fair: Make EAS wakeup placement consider uclamp= restrictions") Signed-off-by: Qais Yousef (Google) --- kernel/sched/fair.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index c6c8e7f52935..7a21ee74139f 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -7382,11 +7382,10 @@ static int find_energy_efficient_cpu(struct task_st= ruct *p, int prev_cpu) for (; pd; pd =3D pd->next) { unsigned long util_min =3D p_util_min, util_max =3D p_util_max; unsigned long cpu_cap, cpu_thermal_cap, util; - unsigned long cur_delta, max_spare_cap =3D 0; + long prev_spare_cap =3D -1, max_spare_cap =3D -1; unsigned long rq_util_min, rq_util_max; - unsigned long prev_spare_cap =3D 0; + unsigned long cur_delta, base_energy; int max_spare_cap_cpu =3D -1; - unsigned long base_energy; int fits, max_fits =3D -1; =20 cpumask_and(cpus, perf_domain_span(pd), cpu_online_mask); @@ -7461,7 +7460,7 @@ static int find_energy_efficient_cpu(struct task_stru= ct *p, int prev_cpu) } } =20 - if (max_spare_cap_cpu < 0 && prev_spare_cap =3D=3D 0) + if (max_spare_cap_cpu < 0 && prev_spare_cap < 0) continue; =20 eenv_pd_busy_time(&eenv, cpus, p); @@ -7469,7 +7468,7 @@ static int find_energy_efficient_cpu(struct task_stru= ct *p, int prev_cpu) base_energy =3D compute_energy(&eenv, pd, cpus, p, -1); =20 /* Evaluate the energy impact of using prev_cpu. */ - if (prev_spare_cap > 0) { + if (prev_spare_cap > -1) { prev_delta =3D compute_energy(&eenv, pd, cpus, p, prev_cpu); /* CPU utilization has changed */ --=20 2.25.1 From nobody Sat Sep 13 03:59:57 2025 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 0B8DDC636CD for ; Sun, 5 Feb 2023 22:43:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229478AbjBEWnk (ORCPT ); Sun, 5 Feb 2023 17:43:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229621AbjBEWng (ORCPT ); Sun, 5 Feb 2023 17:43:36 -0500 Received: from mail-ej1-x633.google.com (mail-ej1-x633.google.com [IPv6:2a00:1450:4864:20::633]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 50DDF1A97A for ; Sun, 5 Feb 2023 14:43:35 -0800 (PST) Received: by mail-ej1-x633.google.com with SMTP id ud5so29496468ejc.4 for ; Sun, 05 Feb 2023 14:43:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=layalina-io.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=iqPeO/kNGQGc1U6cNoUfj1cL/02jGGj55jKIfeMBJNg=; b=apA3c6eDRcMeQ3Nve4KdAFI74pKWD9vJPKKZpCZ/HAILY0DgzjeQcRi8Zb9Zkf8TqJ 4Rn8f9MDiKOJ0oeNkWy/rmJtbw7/VfoxMWzPnKw1PRj0r3v+ubz8dwRO/76dBhWn28cn WWELacMc7LuFipok14FAxsmsSLq0A2UrB4jgEetCe6fEITMmMtAeK9o2pyPjaTVt2QIh oDyRaNdUKF+AlM5v/lcZLFfd78jjKoFuFNT5P6Di66OQdl3Y1tG7swhrK/i3Kqrs8Urv rJR53AfbAQ2M4lH8HRSnBd21qh+viMQWXsIhp/3iTHPBzlV8QC0Eq+GELeuhGcGm4/a1 9R5A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=iqPeO/kNGQGc1U6cNoUfj1cL/02jGGj55jKIfeMBJNg=; b=BDQ1VUAw+hJfE37QpViYQVd6egoE/4pVM4BAOkWslmzJunkp38fFXLdIuolPKfSWft P9rbQzmqMzkS53kmDVRChfBTNjD+fvIcfkAISjZIAZT8eE2BbZlx1TVUxgaEGjlALC9g MaWm56gCQHnIVgYviVHoqy/SX1uLUObg8+3yXIcs8I7/CAwEF0INYQy+6OxK7MxDTCLQ WpyLef73BkjIKXfBx8thE3FlfVfOObvbgGark64h4sM7nrXPc0LHyMHkorh2h3Lr1AGw 7EYRQS0sT73N1CZlWKu6Mej2qnrnzOxHncyGDv7PEAbZkt6/fcVPzBox37ekar2Y6pBP oqpQ== X-Gm-Message-State: AO0yUKWX5aYV736TxPjD8+wBAZSsVMSUPFhKY5xmnXLF+GZ5i0BmDS+S +bcOzgB8JlWxPRKygeUWh/fCReKm/fpd1Ktz X-Google-Smtp-Source: AK7set+65pkNQe/XnpAQI7bikzIj1Nwh1bGanSkPTNADGJbVb43oKSusNwotgp6TmYKgpjLB9QreMg== X-Received: by 2002:a17:906:1291:b0:88a:73b7:6d5f with SMTP id k17-20020a170906129100b0088a73b76d5fmr14446059ejb.10.1675637013831; Sun, 05 Feb 2023 14:43:33 -0800 (PST) Received: from localhost.localdomain (host86-163-35-10.range86-163.btcentralplus.com. [86.163.35.10]) by smtp.gmail.com with ESMTPSA id m15-20020a1709061ecf00b0087bd2924e74sm4550779ejj.205.2023.02.05.14.43.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 05 Feb 2023 14:43:33 -0800 (PST) From: Qais Yousef To: Ingo Molnar , Peter Zijlstra , Vincent Guittot , Dietmar Eggemann Cc: linux-kernel@vger.kernel.org, Lukasz Luba , Wei Wang , Xuewen Yan , Hank , Jonathan JMChen , Qais Yousef Subject: [PATCH v2 2/3] sched/uclamp: Ignore (util == 0) optimization in feec() when p_util_max = 0 Date: Sun, 5 Feb 2023 22:43:17 +0000 Message-Id: <20230205224318.2035646-3-qyousef@layalina.io> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230205224318.2035646-1-qyousef@layalina.io> References: <20230205224318.2035646-1-qyousef@layalina.io> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" find_energy_efficient_cpu() bails out early if effective util of the task is 0. When uclamp is being used, this could lead to wrong decisions when uclamp_max is set to 0. Cater for that. Fixes: d81304bc6193 ("sched/uclamp: Cater for uclamp in find_energy_efficie= nt_cpu()'s early exit condition") Signed-off-by: Qais Yousef --- kernel/sched/fair.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 7a21ee74139f..a8c3d92ff3f6 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -7374,7 +7374,7 @@ static int find_energy_efficient_cpu(struct task_stru= ct *p, int prev_cpu) target =3D prev_cpu; =20 sync_entity_load_avg(&p->se); - if (!uclamp_task_util(p, p_util_min, p_util_max)) + if (!uclamp_task_util(p, p_util_min, p_util_max) && p_util_max !=3D 0) goto unlock; =20 eenv_task_busy_time(&eenv, p, prev_cpu); --=20 2.25.1 From nobody Sat Sep 13 03:59:57 2025 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 7BC5DC636CC for ; Sun, 5 Feb 2023 22:43:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229468AbjBEWnm (ORCPT ); Sun, 5 Feb 2023 17:43:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50002 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229559AbjBEWni (ORCPT ); Sun, 5 Feb 2023 17:43:38 -0500 Received: from mail-ej1-x629.google.com (mail-ej1-x629.google.com [IPv6:2a00:1450:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2B6021B55C for ; Sun, 5 Feb 2023 14:43:37 -0800 (PST) Received: by mail-ej1-x629.google.com with SMTP id e22so158033ejb.1 for ; Sun, 05 Feb 2023 14:43:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=layalina-io.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=/esgXyXTTPxQhwv1dQWaspfNIbrAOoa4gfi3afJxYbI=; b=saj4RMnp18qzp3YrMX0TvOgrT4AhT+MZWfVpznyOwkspaZ7mHFNPNL8wgFYJ8UpNe2 QsY1OW+ovidQImrOqpQ9IrUAxLltUpGfv2ST1CYutfGFZTPFpK0gMsqLjI5o3qVXQI5h ln17Y+sihiyTJ8pTngx/S0qj64QlZp29zrWuMc3rJaM49/yX+pZMq+oiCpT+g5Y5iwmC xgNjXnKZiJ1E6Ek+5FOptZFgcUIrSP/isqFSGiFWhR8FQEruttKhC2prknON/QJ5Vzmu nYiG57CCGb+nhFsyRnztxW8+ojJKINiXYn/irMUP+pNILIMlZVC8q1JNwUKGVOTZJyZG Kimg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=/esgXyXTTPxQhwv1dQWaspfNIbrAOoa4gfi3afJxYbI=; b=8IZb2VLAuK+zGtyKN3/oQVor0INGUBbIQoMk3eOiYsawhpbhwP2b2tLcsHrBT85fK6 2UOmVSgNY3pvblsb6ZXwqGBd02bo8zPrviiVrclPUkTQ8mv0ZWMZn8UGGjnBcRXhdnTY krLEVIzvIv5TQoJH/cPGqGVRW15+WUjVy7m4U5P8IMoX+OQcnKVpEGEpHLFlFh+MSGX4 zqyC41Kvm7Bf9CqxUKOzx0gROe57lGKf+70uJbPpZ4UchR/xf7bIW4HRMCKlAuLQhjxS hlVNVJhLXCHC94tEqMb9LwWRERKWGuBcQrHmoVC2JOB4Jid24lo+KNIO+j3RUOFz5tqd mRwQ== X-Gm-Message-State: AO0yUKXaR+MlOSF/UuKlSTHLzRzDVyoldl0f4YfWo3tE6ImgvEbyRKMi jSCeHPMFaSlKgGkv5Ob9cGAoag== X-Google-Smtp-Source: AK7set9x6yzo6Wo4YON2oMsfFHFTT1az+lMFwyR2a9shTwnRZ2GKEOSxqwMEwjj2XLAUjhkQEsfMjg== X-Received: by 2002:a17:906:4c84:b0:88a:da35:dd51 with SMTP id q4-20020a1709064c8400b0088ada35dd51mr17534300eju.14.1675637015794; Sun, 05 Feb 2023 14:43:35 -0800 (PST) Received: from localhost.localdomain (host86-163-35-10.range86-163.btcentralplus.com. [86.163.35.10]) by smtp.gmail.com with ESMTPSA id m15-20020a1709061ecf00b0087bd2924e74sm4550779ejj.205.2023.02.05.14.43.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 05 Feb 2023 14:43:35 -0800 (PST) From: Qais Yousef To: Ingo Molnar , Peter Zijlstra , Vincent Guittot , Dietmar Eggemann Cc: linux-kernel@vger.kernel.org, Lukasz Luba , Wei Wang , Xuewen Yan , Hank , Jonathan JMChen , Qais Yousef Subject: [PATCH v2 3/3] sched/tp: Add new tracepoint to track compute energy computation Date: Sun, 5 Feb 2023 22:43:18 +0000 Message-Id: <20230205224318.2035646-4-qyousef@layalina.io> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230205224318.2035646-1-qyousef@layalina.io> References: <20230205224318.2035646-1-qyousef@layalina.io> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" It was useful to track feec() placement decision and debug the spare capacity and optimization issues vs uclamp_max. Signed-off-by: Qais Yousef --- include/trace/events/sched.h | 4 ++++ kernel/sched/core.c | 1 + kernel/sched/fair.c | 7 ++++++- 3 files changed, 11 insertions(+), 1 deletion(-) diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h index fbb99a61f714..20cc884f72ff 100644 --- a/include/trace/events/sched.h +++ b/include/trace/events/sched.h @@ -735,6 +735,10 @@ DECLARE_TRACE(sched_update_nr_running_tp, TP_PROTO(struct rq *rq, int change), TP_ARGS(rq, change)); =20 +DECLARE_TRACE(sched_compute_energy_tp, + TP_PROTO(struct task_struct *p, int dst_cpu, unsigned long energy), + TP_ARGS(p, dst_cpu, energy)); + #endif /* _TRACE_SCHED_H */ =20 /* This part must be outside protection */ diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 4580fe3e1d0c..5f6dde9b892b 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -110,6 +110,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(sched_overutilized_tp); EXPORT_TRACEPOINT_SYMBOL_GPL(sched_util_est_cfs_tp); EXPORT_TRACEPOINT_SYMBOL_GPL(sched_util_est_se_tp); EXPORT_TRACEPOINT_SYMBOL_GPL(sched_update_nr_running_tp); +EXPORT_TRACEPOINT_SYMBOL_GPL(sched_compute_energy_tp); =20 DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); =20 diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index a8c3d92ff3f6..801e903c4307 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -7295,11 +7295,16 @@ compute_energy(struct energy_env *eenv, struct perf= _domain *pd, { unsigned long max_util =3D eenv_pd_max_util(eenv, pd_cpus, p, dst_cpu); unsigned long busy_time =3D eenv->pd_busy_time; + unsigned long energy; =20 if (dst_cpu >=3D 0) busy_time =3D min(eenv->pd_cap, busy_time + eenv->task_busy_time); =20 - return em_cpu_energy(pd->em_pd, max_util, busy_time, eenv->cpu_cap); + energy =3D em_cpu_energy(pd->em_pd, max_util, busy_time, eenv->cpu_cap); + + trace_sched_compute_energy_tp(p, dst_cpu, energy); + + return energy; } =20 /* --=20 2.25.1