Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754348Ab3EXLe4 (ORCPT ); Fri, 24 May 2013 07:34:56 -0400 Received: from mailout1.samsung.com ([203.254.224.24]:51877 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752459Ab3EXLey (ORCPT ); Fri, 24 May 2013 07:34:54 -0400 X-AuditID: cbfee61a-b7f3b6d000006edd-39-519f505d2413 Date: Fri, 24 May 2013 13:34:42 +0200 From: Lukasz Majewski To: Viresh Kumar Cc: Daniel Lezcano , Jonghwa Lee , "Rafael J. Wysocky" , linux-kernel@vger.kernel.org, cpufreq@vger.kernel.org, linux-pm@vger.kernel.org, Vicent Guittot , MyungJoo Ham , Lukasz Majewski Subject: Re: [RFC v2 0/3][TESTS] LAB: Support for Legacy Application Booster governor - tests results Message-id: <20130524133442.7e065145@amdc308.digital.local> In-reply-to: References: <1367590072-10496-1-git-send-email-jonghwa3.lee@samsung.com> <20130522122700.104ca5cd@amdc308.digital.local> <20130522164453.29cd3a7d@amdc308.digital.local> <20130524075640.0a5b80ff@amdc308.digital.local> <20130524103007.7bb206ee@amdc308.digital.local> <519F2D89.5030602@linaro.org> Organization: SPRC Poland X-Mailer: Claws Mail 3.8.1 (GTK+ 2.24.10; x86_64-pc-linux-gnu) MIME-version: 1.0 Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrCLMWRmVeSWpSXmKPExsVy+t9jAd3YgPmBBgv+KVk8bfrBbjHvs6xF 59knzBZvHnFbXN41h83ic+8RRovbjSvYLPoX9jJZdBz5xmyx8auHA5fHnWt72DzWTXvL7NG3 ZRWjx6PFLYwenzfJBbBGcdmkpOZklqUW6dslcGWcnf+NtWCaQMXfCawNjOd4uhg5OSQETCQW /5vLBmGLSVy4tx7I5uIQEljEKPHycTeU084kMfHsRiaQKhYBVYmjd7Yxg9hsAnoSn+8+BYpz cIgIaEm8vJkKUs8scIFJ4uC2zYwgNcIC6RL/tnWB9fIKWEv8P7meBcTmFAiW+L7sNivEgsms EnOe7QFr4BeQlGj/94MZ4iQ7iXOfNrBDNAtK/Jh8D6yZGWjZ5m1NrBC2vMTmNW+ZJzAKzkJS NgtJ2SwkZQsYmVcxiqYWJBcUJ6XnGuoVJ+YWl+al6yXn525iBMfFM6kdjCsbLA4xCnAwKvHw ztCZFyjEmlhWXJl7iFGCg1lJhHcW3/xAId6UxMqq1KL8+KLSnNTiQ4zSHCxK4rwHWq0DhQTS E0tSs1NTC1KLYLJMHJxSDYyOhtvrF5/u2if7wk11dkOldr7gorM2z27wPvVacfvAw+aGl2/k 7b+4xs6cu/nVlZIZjj7Td3tOyre5WF1XapD67p2jieX09v1tj+yM+FK39L3RjZeSSjrwRJl/ yf8JMyfzVJ/hlZ05S2XH0Sz5JublLWpcbmuW3uO7Y7JykZXgLhuLVw1vQxmVWIozEg21mIuK EwHpA5NThwIAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2255 Lines: 65 Hi Viresh, > On 24 May 2013 14:36, Daniel Lezcano > wrote: > > I agree with Viresh, a new governor is not necessary here for that. > > Their patchset had two parts.. One is LAB and other is overclocking. > We are trying to solve overclocking for which they never wanted a > new governor. :) Overclocking can be uses as a standalone feature. However it is crucial for effective LAB operation. > > > There is the /sys/devices/system/cpufreq/boost option existing for > > x86 platform, why do not reuse it ? It is supposed to do exactly > > what you want to achieve. > > The problem is that it was added at the wrong place.. It should have > been at cpu/cpuX/cpufreq/boost... > > Consider how will we achieve it for big LITTLE.. We know we can > go to overdrive only for a single core in big but for two cores in > LITTLE at the same time.. So, we need that in the location I just > mentioned... I think that power/thermal envelope here is a key. We can overclock as many cores as we want if we don't exceed limits :-) Scheduler assignment of tasks to cores and core type decision on which it would run is a different story for b.L. > > Over that.. I believe it is governor specific too.. It shouldn't be > part of conservative as it should be conservative rather then > aggressive :) > > > IMO, the logic of boosting one core when the other are idle should > > be in the driver itself and certainly not setup by the user, except > > if we consider acceptable the user can burn its board ... :) Sysfs entry can be read only and governor code can be responsible for enabling overclocking. Overclocking patch provides API implemented at cpufreq.h file to allow in-kernel overclocking. > > I didn't get it completely.. So, with the options I gave user can only > say.. boost if required and only when few cores are active. User > can't just set max freq continuously if he wishes.. -- Best regards, Lukasz Majewski Samsung R&D Poland (SRPOL) | Linux Platform Group -- 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/