From nobody Sat Apr 11 23:02:58 2026 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 6955CC19F2D for ; Thu, 4 Aug 2022 14:37:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239942AbiHDOhX (ORCPT ); Thu, 4 Aug 2022 10:37:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49780 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239839AbiHDOgx (ORCPT ); Thu, 4 Aug 2022 10:36:53 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 6874E4B490 for ; Thu, 4 Aug 2022 07:36:52 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8FA581480; Thu, 4 Aug 2022 07:36:52 -0700 (PDT) Received: from localhost.localdomain (unknown [10.57.10.177]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 63C8A3F73B; Thu, 4 Aug 2022 07:36:50 -0700 (PDT) From: Qais Yousef To: Ingo Molnar , "Peter Zijlstra (Intel)" , Vincent Guittot , Dietmar Eggemann Cc: linux-kernel@vger.kernel.org, Xuewen Yan , Lukasz Luba , Wei Wang , Jonathan JMChen , Hank , Qais Yousef Subject: [PATCH v2 7/9] sched/uclamp: Cater for uclamp in find_energy_efficient_cpu()'s early exit condition Date: Thu, 4 Aug 2022 15:36:07 +0100 Message-Id: <20220804143609.515789-8-qais.yousef@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220804143609.515789-1-qais.yousef@arm.com> References: <20220804143609.515789-1-qais.yousef@arm.com> 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" If the utilization of the woken up task is 0, we skip the energy calculation because it has no impact. But if the task is boosted (uclamp_min !=3D 0) will have an impact on task placement and frequency selection. Only skip if the util is truly 0 after applying uclamp values. Change uclamp_task_cpu() signature to avoid unnecessary additional calls to uclamp_eff_get(). feec() is the only user now. Fixes: 732cd75b8c920 ("sched/fair: Select an energy-efficient CPU on task w= ake-up") Signed-off-by: Qais Yousef --- kernel/sched/fair.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 4c3a5240d7e3..59ba7106ddc6 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4108,14 +4108,16 @@ static inline unsigned long task_util_est(struct ta= sk_struct *p) } =20 #ifdef CONFIG_UCLAMP_TASK -static inline unsigned long uclamp_task_util(struct task_struct *p) +static inline unsigned long uclamp_task_util(struct task_struct *p, + unsigned long uclamp_min, + unsigned long uclamp_max) { - return clamp(task_util_est(p), - uclamp_eff_value(p, UCLAMP_MIN), - uclamp_eff_value(p, UCLAMP_MAX)); + return clamp(task_util_est(p), uclamp_min, uclamp_max); } #else -static inline unsigned long uclamp_task_util(struct task_struct *p) +static inline unsigned long uclamp_task_util(struct task_struct *p, + unsigned long uclamp_min, + unsigned long uclamp_max) { return task_util_est(p); } @@ -7029,7 +7031,7 @@ 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 (!task_util_est(p)) + if (!uclamp_task_util(p, p_util_min, p_util_max)) goto unlock; =20 eenv_task_busy_time(&eenv, p, prev_cpu); --=20 2.25.1