From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757112AbaFALdl (ORCPT ); Sun, 1 Jun 2014 07:33:41 -0400 Received: from service87.mimecast.com ([91.220.42.44]:43572 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757029AbaFALdk convert rfc822-to-8bit (ORCPT ); Sun, 1 Jun 2014 07:33:40 -0400 Message-ID: <538B0F90.8090902@arm.com> Date: Sun, 01 Jun 2014 12:33:36 +0100 From: Dietmar Eggemann User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Vincent Guittot CC: "peterz@infradead.org" , "mingo@kernel.org" , "linux-kernel@vger.kernel.org" , "linux@arm.linux.org.uk" , "linux-arm-kernel@lists.infradead.org" , "preeti@linux.vnet.ibm.com" , Morten Rasmussen , "efault@gmx.de" , "nicolas.pitre@linaro.org" , "linaro-kernel@lists.linaro.org" , "daniel.lezcano@linaro.org" Subject: Re: [PATCH v2 08/11] sched: get CPU's activity statistic References: <1400860385-14555-1-git-send-email-vincent.guittot@linaro.org> <1400860385-14555-9-git-send-email-vincent.guittot@linaro.org> <5388546E.5070007@arm.com> In-Reply-To: X-OriginalArrivalTime: 01 Jun 2014 11:33:35.0890 (UTC) FILETIME=[5353DF20:01CF7D8D] X-MC-Unique: 114060112333800301 Content-Type: text/plain; charset=WINDOWS-1252; format=flowed Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 30/05/14 20:20, Vincent Guittot wrote: > On 30 May 2014 11:50, Dietmar Eggemann wrote: >> On 23/05/14 16:53, Vincent Guittot wrote: >>> Monitor the activity level of each group of each sched_domain level. The >>> activity is the amount of cpu_power that is currently used on a CPU or group >>> of CPUs. We use the runnable_avg_sum and _period to evaluate this activity >>> level. In the special use case where the CPU is fully loaded by more than 1 >>> task, the activity level is set above the cpu_power in order to reflect the >>> overload of the CPU >>> >>> Signed-off-by: Vincent Guittot >> >> [...] >> >>> /* >>> * select_task_rq_fair: Select target runqueue for the waking task in domains >>> * that have the 'sd_flag' flag set. In practice, this is SD_BALANCE_WAKE, >>> @@ -5518,6 +5535,7 @@ struct sg_lb_stats { >>> unsigned long sum_weighted_load; /* Weighted load of group's tasks */ >>> unsigned long load_per_task; >>> unsigned long group_power; >>> + unsigned long group_activity; /* Total activity of the group */ >>> unsigned int sum_nr_running; /* Nr tasks running in the group */ >>> unsigned int group_capacity; >>> unsigned int idle_cpus; >>> @@ -5538,6 +5556,7 @@ struct sd_lb_stats { >>> struct sched_group *busiest; /* Busiest group in this sd */ >>> struct sched_group *local; /* Local group in this sd */ >>> unsigned long total_load; /* Total load of all groups in sd */ >>> + unsigned long total_activity; /* Total activity of all groups in sd */ >>> unsigned long total_pwr; /* Total power of all groups in sd */ >>> unsigned long avg_load; /* Average load across all groups in sd */ >>> >>> @@ -5557,6 +5576,7 @@ static inline void init_sd_lb_stats(struct sd_lb_stats *sds) >>> .busiest = NULL, >>> .local = NULL, >>> .total_load = 0UL, >>> + .total_activity = 0UL, >> >> AFAICS, total_activity is not used right now. Do you intend to use it to >> calculate something like avg_activity later (like total_load/avg_load)? > > this patch only creates group_activity and total_activity.The use of > these statistics appears on the next patches. I have not planned to > compute such avg_activity for the moment mainly because i have need it > yet. > > Do you have in mind any use of such avg_activity ? No, not really but I still don't see (taken all your patches) where sds->total_activity is used. $ find . -name "*.[ch]" | xargs grep total_activity ./kernel/sched/fair.c: unsigned long total_activity; /* Total activity of all groups in sd */ ./kernel/sched/fair.c: .total_activity = 0UL, ./kernel/sched/fair.c: sds->total_activity += sgs->group_activity; OOTH, sgs->group_activity is used to set sgs->group_capacity which is then used in if conditions in update_sd_pick_busiest(), update_sd_lb_stats() and find_busiest_group(). [...]