Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759441AbaGCQ1P (ORCPT ); Thu, 3 Jul 2014 12:27:15 -0400 Received: from service87.mimecast.com ([91.220.42.44]:48358 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759085AbaGCQ1M (ORCPT ); Thu, 3 Jul 2014 12:27:12 -0400 From: Morten Rasmussen To: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, peterz@infradead.org, mingo@kernel.org Cc: rjw@rjwysocki.net, vincent.guittot@linaro.org, daniel.lezcano@linaro.org, preeti@linux.vnet.ibm.com, Dietmar.Eggemann@arm.com, pjt@google.com Subject: [RFCv2 PATCH 17/23] sched: Likely idle state statistics placeholder Date: Thu, 3 Jul 2014 17:26:04 +0100 Message-Id: <1404404770-323-18-git-send-email-morten.rasmussen@arm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1404404770-323-1-git-send-email-morten.rasmussen@arm.com> References: <1404404770-323-1-git-send-email-morten.rasmussen@arm.com> X-OriginalArrivalTime: 03 Jul 2014 16:26:20.0272 (UTC) FILETIME=[85BBDF00:01CF96DB] X-MC-Unique: 114070317262108801 Content-Type: text/plain; charset=WINDOWS-1252 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id s63GRLVD010643 The scheduler is currently completely unaware of idle-states. To make informed decisions using the sched_group_energy idle_states list it is necessary to know which idle-state a cpu (or group of cpus) is most likely to be in when it is idle. For example when migrating a task that wakes up periodically, the wakeup energy expense depends on the idle-state the destination cpu is most likely to be in when idle. Signed-off-by: Morten Rasmussen --- kernel/sched/fair.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 9720f04..353e2d0 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4254,6 +4254,19 @@ static inline bool energy_aware(void) return sched_feat(ENERGY_AWARE); } +/* + * Returns the index of the most likely idle-state that the sched_group is in + * when idle. The index can be used to identify the idle-state in the + * sched_group_energy idle_states list. + * + * This is currently just a placeholder. The information needs to come from + * cpuidle. + */ +static inline int likely_idle_state_idx(struct sched_group *sg) +{ + return 0; +} + static int wake_wide(struct task_struct *p) { int factor = this_cpu_read(sd_llc_size); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/