From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 BAC47C32792 for ; Thu, 3 Oct 2019 12:46:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8780321783 for ; Thu, 3 Oct 2019 12:46:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="eXzEMFeA" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729941AbfJCMp5 (ORCPT ); Thu, 3 Oct 2019 08:45:57 -0400 Received: from mail-wm1-f65.google.com ([209.85.128.65]:36011 "EHLO mail-wm1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729359AbfJCMpz (ORCPT ); Thu, 3 Oct 2019 08:45:55 -0400 Received: by mail-wm1-f65.google.com with SMTP id m18so2205113wmc.1 for ; Thu, 03 Oct 2019 05:45:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id; bh=odawl8FFS06ZpSGBB5Pezvvx3lJRWzOpGgq0TcvgjOg=; b=eXzEMFeArLL+ICpbrKdS4nZIvxGIsv9szP47e2Caat9Upd4ahEHkh/EUEGqq0FkWim GkCRNtBWf9mb3jxW2NBD/0xXomLrraOhr5bqHp8jXEkzX+WUSi+TtKS+h4FxXpuNMrOx nSpkoOVSqmtk25a+y2IG5cwf/cvm2GLY1an9u+OuFL/JbQYG3Tq8qxyAfwdPmNjNpWO9 doBIs+mnugic49SRHqccja4VtqLEVD12e9EFpyJYu+hyU7Op5/0rYVwWpzmmf6oLdzZA NtBci8rH7XJ5TIymO+Chh+IceKCdvoZoFkmvApWWzROTJv/xLVA1ha0ynVDUf7ybXpH2 A5hw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=odawl8FFS06ZpSGBB5Pezvvx3lJRWzOpGgq0TcvgjOg=; b=fdCiIyw7zufUeOE0tbEhmXCOxtlHrgeZnobBhDC+K+KPfGwF2ieeqZDDujKcVlzNin 68gTvv+pktdDoCnq55PONBg2A2NZ71GxyQuadxXUGBX3GZFGAUssfZpl2Os/wrv6LBTe 6dYcdVqnEZjI1x84uIsdCm2aTNpee/C7PX3UOlrj2hjrWi1jVK4hWAAuz0btzBUXkHjH 0/nfEShAsnEy+VHborV9A/bbt7aT7R/9safWK8Nm3LgDo/53Sd3okIEW6OCXuJimfI7U 7zKsGgftin62oRVyOolEm+j2qrofR/yg18U1Eg02l0chxDLL5hnv+aDED3CNNMGXYE8T xXpA== X-Gm-Message-State: APjAAAVnGRZt0Hot+OhEeJd7a4UDYZVKmXVH1/BO90J1UQpuX+kj4GlA UBhATjX0aaL3SV/jCY4qxsnc5A== X-Google-Smtp-Source: APXvYqw9d+ege8Jhzjtl7OmV6mrlYg8kMbClHGN3oHAP7HUb3lcxXV6K+oxPWdt4U8xYjQCyPCM8xw== X-Received: by 2002:a05:600c:2186:: with SMTP id e6mr7307474wme.154.1570106752320; Thu, 03 Oct 2019 05:45:52 -0700 (PDT) Received: from localhost.localdomain ([2a01:e34:ed2f:f020:7990:8bfa:5771:282b]) by smtp.gmail.com with ESMTPSA id m62sm2453586wmm.35.2019.10.03.05.45.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 03 Oct 2019 05:45:51 -0700 (PDT) From: Daniel Lezcano To: rjw@rjwysocki.net Cc: Mathieu Poirier , Ingo Molnar , Peter Zijlstra , linux-pm@vger.kernel.org (open list:CPU IDLE TIME MANAGEMENT FRAMEWORK), linux-kernel@vger.kernel.org (open list) Subject: [PATCH V3 1/3] cpuidle: play_idle: Make play_idle more flexible Date: Thu, 3 Oct 2019 14:45:39 +0200 Message-Id: <20191003124541.27147-1-daniel.lezcano@linaro.org> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The play_idle function has two users, the intel powerclamp and the idle_injection. The idle injection cooling device uses the function via the idle_injection powercap's APIs. Unfortunately, play_idle is currently limited by the idle state depth: by default the deepest idle state is selected. On the ARM[64] platforms, most of the time it is the cluster idle state, the exit latency and the residency can be very high. That reduces the scope of the idle injection usage because the impact on the performances can be very significant. If the idle injection cycles can be done with a shallow state like a retention state, the cooling effect would eventually give similar results than the cpufreq cooling device. In order to prepare the function to receive an idle state parameter, let's replace the 'use_deepest_state' boolean field with 'use_state' and use this value to enter the specific idle state. The current code keeps the default behavior which is go to the deepest idle state. Signed-off-by: Daniel Lezcano Acked-by: Mathieu Poirier --- drivers/cpuidle/cpuidle.c | 21 +++++++++++---------- include/linux/cpuidle.h | 13 ++++++------- kernel/sched/idle.c | 10 +++++----- 3 files changed, 22 insertions(+), 22 deletions(-) diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 0895b988fa92..f8b54f277589 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -99,31 +99,31 @@ static int find_deepest_state(struct cpuidle_driver *drv, } /** - * cpuidle_use_deepest_state - Set/clear governor override flag. - * @enable: New value of the flag. + * cpuidle_use_state - Force the cpuidle framework to enter an idle state. + * @state: An integer for an idle state * - * Set/unset the current CPU to use the deepest idle state (override governors - * going forward if set). + * Specify an idle state the cpuidle framework must step in and bypass + * the idle state selection process. */ -void cpuidle_use_deepest_state(bool enable) +void cpuidle_use_state(int state) { struct cpuidle_device *dev; preempt_disable(); dev = cpuidle_get_device(); if (dev) - dev->use_deepest_state = enable; + dev->use_state = state; preempt_enable(); } /** * cpuidle_find_deepest_state - Find the deepest available idle state. - * @drv: cpuidle driver for the given CPU. - * @dev: cpuidle device for the given CPU. */ -int cpuidle_find_deepest_state(struct cpuidle_driver *drv, - struct cpuidle_device *dev) +int cpuidle_find_deepest_state(void) { + struct cpuidle_device *dev = cpuidle_get_device(); + struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); + return find_deepest_state(drv, dev, UINT_MAX, 0, false); } @@ -554,6 +554,7 @@ static void __cpuidle_unregister_device(struct cpuidle_device *dev) static void __cpuidle_device_init(struct cpuidle_device *dev) { memset(dev->states_usage, 0, sizeof(dev->states_usage)); + dev->use_state = CPUIDLE_STATE_NOUSE; dev->last_residency = 0; dev->next_hrtimer = 0; } diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index 2dc4c6b19c25..ba0751b26e37 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -15,6 +15,7 @@ #include #include +#define CPUIDLE_STATE_NOUSE -1 #define CPUIDLE_STATE_MAX 10 #define CPUIDLE_NAME_LEN 16 #define CPUIDLE_DESC_LEN 32 @@ -80,11 +81,11 @@ struct cpuidle_driver_kobj; struct cpuidle_device { unsigned int registered:1; unsigned int enabled:1; - unsigned int use_deepest_state:1; unsigned int poll_time_limit:1; unsigned int cpu; ktime_t next_hrtimer; + int use_state; int last_state_idx; int last_residency; u64 poll_limit_ns; @@ -203,19 +204,17 @@ static inline struct cpuidle_device *cpuidle_get_device(void) {return NULL; } #endif #ifdef CONFIG_CPU_IDLE -extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv, - struct cpuidle_device *dev); +extern int cpuidle_find_deepest_state(void); extern int cpuidle_enter_s2idle(struct cpuidle_driver *drv, struct cpuidle_device *dev); -extern void cpuidle_use_deepest_state(bool enable); +extern void cpuidle_use_state(int state); #else -static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv, - struct cpuidle_device *dev) +static inline int cpuidle_find_deepest_state(void) {return -ENODEV; } static inline int cpuidle_enter_s2idle(struct cpuidle_driver *drv, struct cpuidle_device *dev) {return -ENODEV; } -static inline void cpuidle_use_deepest_state(bool enable) +static inline void cpuidle_use_state(int state) { } #endif diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index b98283fc6914..17da9cb309e1 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -165,7 +165,8 @@ static void cpuidle_idle_call(void) * until a proper wakeup interrupt happens. */ - if (idle_should_enter_s2idle() || dev->use_deepest_state) { + if (idle_should_enter_s2idle() || + dev->use_state != CPUIDLE_STATE_NOUSE) { if (idle_should_enter_s2idle()) { rcu_idle_enter(); @@ -181,8 +182,7 @@ static void cpuidle_idle_call(void) tick_nohz_idle_stop_tick(); rcu_idle_enter(); - next_state = cpuidle_find_deepest_state(drv, dev); - call_cpuidle(drv, dev, next_state); + call_cpuidle(drv, dev, dev->use_state); } else { bool stop_tick = true; @@ -328,7 +328,7 @@ void play_idle(unsigned long duration_us) rcu_sleep_check(); preempt_disable(); current->flags |= PF_IDLE; - cpuidle_use_deepest_state(true); + cpuidle_use_state(cpuidle_find_deepest_state()); it.done = 0; hrtimer_init_on_stack(&it.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); @@ -339,7 +339,7 @@ void play_idle(unsigned long duration_us) while (!READ_ONCE(it.done)) do_idle(); - cpuidle_use_deepest_state(false); + cpuidle_use_state(CPUIDLE_STATE_NOUSE); current->flags &= ~PF_IDLE; preempt_fold_need_resched(); -- 2.17.1