From nobody Thu Dec 18 15:07:22 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 216AFC4167B for ; Wed, 29 Nov 2023 11:09:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232810AbjK2LJA (ORCPT ); Wed, 29 Nov 2023 06:09:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56056 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232450AbjK2LIe (ORCPT ); Wed, 29 Nov 2023 06:08:34 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 6AAA61FEB; Wed, 29 Nov 2023 03:08:26 -0800 (PST) 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 422322F4; Wed, 29 Nov 2023 03:09:13 -0800 (PST) Received: from e129166.arm.com (unknown [10.57.4.241]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id A925C3F5A1; Wed, 29 Nov 2023 03:08:23 -0800 (PST) From: Lukasz Luba To: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, rafael@kernel.org Cc: lukasz.luba@arm.com, dietmar.eggemann@arm.com, rui.zhang@intel.com, amit.kucheria@verdurent.com, amit.kachhap@gmail.com, daniel.lezcano@linaro.org, viresh.kumar@linaro.org, len.brown@intel.com, pavel@ucw.cz, mhiramat@kernel.org, qyousef@layalina.io, wvw@google.com Subject: [PATCH v5 09/23] PM: EM: Use runtime modified EM for CPUs energy estimation in EAS Date: Wed, 29 Nov 2023 11:08:39 +0000 Message-Id: <20231129110853.94344-10-lukasz.luba@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231129110853.94344-1-lukasz.luba@arm.com> References: <20231129110853.94344-1-lukasz.luba@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" The new Energy Model (EM) supports runtime modification of the performance state table to better model the power used by the SoC. Use this new feature to improve energy estimation and therefore task placement in Energy Aware Scheduler (EAS). Signed-off-by: Lukasz Luba --- include/linux/energy_model.h | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/include/linux/energy_model.h b/include/linux/energy_model.h index 1e618e431cac..94a77a813724 100644 --- a/include/linux/energy_model.h +++ b/include/linux/energy_model.h @@ -238,6 +238,7 @@ static inline unsigned long em_cpu_energy(struct em_per= f_domain *pd, unsigned long max_util, unsigned long sum_util, unsigned long allowed_cpu_cap) { + struct em_perf_table *runtime_table; unsigned long freq, scale_cpu; struct em_perf_state *ps; int cpu, i; @@ -255,7 +256,14 @@ static inline unsigned long em_cpu_energy(struct em_pe= rf_domain *pd, */ cpu =3D cpumask_first(to_cpumask(pd->cpus)); scale_cpu =3D arch_scale_cpu_capacity(cpu); - ps =3D &pd->table[pd->nr_perf_states - 1]; + + /* + * No rcu_read_lock() since it's already called by task scheduler. + * The runtime_table is always there for CPUs, so we don't check. + */ + runtime_table =3D rcu_dereference(pd->runtime_table); + + ps =3D &runtime_table->state[pd->nr_perf_states - 1]; =20 max_util =3D map_util_perf(max_util); max_util =3D min(max_util, allowed_cpu_cap); @@ -265,9 +273,9 @@ static inline unsigned long em_cpu_energy(struct em_per= f_domain *pd, * Find the lowest performance state of the Energy Model above the * requested frequency. */ - i =3D em_pd_get_efficient_state(pd->table, pd->nr_perf_states, freq, - pd->flags); - ps =3D &pd->table[i]; + i =3D em_pd_get_efficient_state(runtime_table->state, pd->nr_perf_states, + freq, pd->flags); + ps =3D &runtime_table->state[i]; =20 /* * The capacity of a CPU in the domain at the performance state (ps) --=20 2.25.1