From patchwork Wed Nov 23 20:13:09 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacob Pan X-Patchwork-Id: 9444293 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 0B8D760778 for ; Wed, 23 Nov 2016 20:16:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 116BD27D16 for ; Wed, 23 Nov 2016 20:16:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0612E27D76; Wed, 23 Nov 2016 20:16:56 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id ADC0227D16 for ; Wed, 23 Nov 2016 20:16:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936366AbcKWUQW (ORCPT ); Wed, 23 Nov 2016 15:16:22 -0500 Received: from mga06.intel.com ([134.134.136.31]:19019 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935936AbcKWUPW (ORCPT ); Wed, 23 Nov 2016 15:15:22 -0500 Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga104.jf.intel.com with ESMTP; 23 Nov 2016 12:14:59 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,539,1473145200"; d="scan'208";a="904868341" Received: from icelake.jf.intel.com ([10.7.199.162]) by orsmga003.jf.intel.com with ESMTP; 23 Nov 2016 12:14:59 -0800 From: Jacob Pan To: Peter Zijlstra , Ingo Molnar , Thomas Gleixner , LKML , Linux PM , Rafael Wysocki Cc: Arjan van de Ven , Srinivas Pandruvada , Len Brown , Eduardo Valentin , Zhang Rui , Petr Mladek , Sebastian Andrzej Siewior , Jacob Pan Subject: [PATCH v3 2/3] cpuidle: allow setting deepest idle Date: Wed, 23 Nov 2016 12:13:09 -0800 Message-Id: <1479931990-11732-3-git-send-email-jacob.jun.pan@linux.intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1479931990-11732-1-git-send-email-jacob.jun.pan@linux.intel.com> References: <1479931990-11732-1-git-send-email-jacob.jun.pan@linux.intel.com> Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When idle injection is used to cap power, we need to override governor's choice of idle states. This patch allows caller to select the deepest idle state on a CPU therefore achieve the maximum potential power saving. Signed-off-by: Jacob Pan --- drivers/cpuidle/cpuidle.c | 11 +++++++++++ include/linux/cpuidle.h | 4 +++- kernel/sched/idle.c | 13 ++++++++----- 3 files changed, 22 insertions(+), 6 deletions(-) diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index c73207a..887a52a 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -97,6 +97,17 @@ static int find_deepest_state(struct cpuidle_driver *drv, return ret; } +/* Set the current cpu to use the deepest idle state, override governors */ +void cpuidle_use_deepest_state(bool enable) +{ + struct cpuidle_device *dev; + + preempt_disable(); + dev = cpuidle_get_device(); + dev->use_deepest_state = enable; + preempt_enable(); +} + #ifdef CONFIG_SUSPEND /** * cpuidle_find_deepest_state - Find the deepest available idle state. diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index bb31373..97c169b 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -74,6 +74,7 @@ struct cpuidle_state { struct cpuidle_device { unsigned int registered:1; unsigned int enabled:1; + unsigned int use_deepest_state:1; unsigned int cpu; int last_residency; @@ -192,11 +193,12 @@ static inline struct cpuidle_driver *cpuidle_get_cpu_driver( static inline struct cpuidle_device *cpuidle_get_device(void) {return NULL; } #endif -#if defined(CONFIG_CPU_IDLE) && defined(CONFIG_SUSPEND) +#ifdef CONFIG_CPU_IDLE extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv, struct cpuidle_device *dev); extern int cpuidle_enter_freeze(struct cpuidle_driver *drv, struct cpuidle_device *dev); +extern void cpuidle_use_deepest_state(bool enable); #else static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv, struct cpuidle_device *dev) diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index cb6442f..2729da5 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -164,11 +164,14 @@ static void cpuidle_idle_call(void) * timekeeping to prevent timer interrupts from kicking us out of idle * until a proper wakeup interrupt happens. */ - if (idle_should_freeze()) { - entered_state = cpuidle_enter_freeze(drv, dev); - if (entered_state > 0) { - local_irq_enable(); - goto exit_idle; + + if (idle_should_freeze() || dev->use_deepest_state) { + if (idle_should_freeze()) { + entered_state = cpuidle_enter_freeze(drv, dev); + if (entered_state > 0) { + local_irq_enable(); + goto exit_idle; + } } next_state = cpuidle_find_deepest_state(drv, dev);