Received: by 2002:a25:8b91:0:0:0:0:0 with SMTP id j17csp1449181ybl; Thu, 5 Dec 2019 01:25:45 -0800 (PST) X-Google-Smtp-Source: APXvYqwWN2cOD6FgHnAwlDrWNh2TCauSgCoj8WWE8IlBon4mBM1TkhHjdHr8iRh3S2m/f5kc/UAK X-Received: by 2002:a9d:5f09:: with SMTP id f9mr6122584oti.259.1575537945423; Thu, 05 Dec 2019 01:25:45 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1575537945; cv=none; d=google.com; s=arc-20160816; b=D9UWyhTSNLK2lUndaqBd0GKHupc4cHZDAYnfKnqttQuCggUFg5ZlcHzfxyPllTkfV0 Akxe34l4+UMISHKaS9Ww2nfpDhjOJOCkJk06qaxaUz7OgYUtkdzgcDA+qlhQoxYzQVhH u8vBf7nXY6hX3tFhjFVwAEMAiYKtJwCdjQaGGNLYANRhEi4WBU7iHuJ7aPkyhWw/QU06 YQ8OuI4vju5uc0O1NVv8ohHMiY4P+9bFBn8vXlPD8FE53LpJqRIFq6YBNTasSn78SIAI c24d325X6y6ahxYUmpI978sOE9VCDdhIAl+n1UzebHOgE0QQHsj3KpozIjyLJCo4qgEB IlvQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding :content-language:in-reply-to:mime-version:user-agent:date :message-id:from:references:cc:to:subject; bh=E153SCdNNqecEBr30nuOIC7H7ufXt7aQm7RqGT7qbC0=; b=ROXdJp8Q6PzS+ftYim3i5LOqz+p7srA8AnQU7JRF0GCWYmuH7Lw6tTSpe9Bb23a0X0 gWe5gVabtF2oK4rRM7Yn1QMwcKlu1HpUc9IbAdi4HbTNGNFNK2ONhayaCaCuLBYgFSZW q4aYkODC5CmR8YiQ9qU7FQUVZub48lNagzcRkO/aYdNToIbDbsIyKqWOTZzMetGPeHSL X8O+2ZugLrHB1GZh9YbAyxBThxPsqcqmo55uPjMGIfXfQjFn1y8NlMhpHG0YIZA7Qe3l EBrUWVAuu/qFiM67I3RMhiiuqEmupxcT1qWeLzb3qsqW4Wb/J+htSgcO59+wbEUX+nP1 0DbQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id d17si4490260otc.245.2019.12.05.01.25.33; Thu, 05 Dec 2019 01:25:45 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729120AbfLEJYy (ORCPT + 99 others); Thu, 5 Dec 2019 04:24:54 -0500 Received: from foss.arm.com ([217.140.110.172]:55202 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726239AbfLEJYx (ORCPT ); Thu, 5 Dec 2019 04:24:53 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2FB6E328; Thu, 5 Dec 2019 01:24:53 -0800 (PST) Received: from [192.168.0.9] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8B2AF3F68E; Thu, 5 Dec 2019 01:24:50 -0800 (PST) Subject: Re: [RFC 1/3] Introduce latency-tolerance as an per-task attribute To: Parth Shah , Qais Yousef Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, mingo@redhat.com, vincent.guittot@linaro.org, patrick.bellasi@matbug.net, valentin.schneider@arm.com, pavel@ucw.cz, dhaval.giani@oracle.com, qperret@qperret.net, David.Laight@ACULAB.COM, morten.rasmussen@arm.com, pjt@google.com, tj@kernel.org, viresh.kumar@linaro.org, rafael.j.wysocki@intel.com, daniel.lezcano@linaro.org References: <20191125094618.30298-1-parth@linux.ibm.com> <20191125094618.30298-2-parth@linux.ibm.com> <20191203083654.3ctttimdiujdt7tl@e107158-lin.cambridge.arm.com> <59044b60-a7d8-9508-4975-06afdcfd33cd@linux.ibm.com> From: Dietmar Eggemann Message-ID: Date: Thu, 5 Dec 2019 10:24:41 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.1 MIME-Version: 1.0 In-Reply-To: <59044b60-a7d8-9508-4975-06afdcfd33cd@linux.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/12/2019 16:47, Parth Shah wrote: > > On 12/3/19 2:06 PM, Qais Yousef wrote: >> On 11/25/19 15:16, Parth Shah wrote: >>> Latency-tolerance indicates the latency requirements of a task with respect >>> to the other tasks in the system. The value of the attribute can be within >>> the range of [-20, 19] both inclusive to be in-line with the values just >>> like task nice values. >>> >>> latency_tolerance = -20 indicates the task to have the least latency as >>> compared to the tasks having latency_tolerance = +19. >>> >>> The latency_tolerance may affect only the CFS SCHED_CLASS by getting >>> latency requirements from the userspace. [...] >>> diff --git a/include/linux/sched/latency_tolerance.h b/include/linux/sched/latency_tolerance.h Do we really need an extra header file for this? I know there is linux/sched/prio.h but couldn't this go into kernel/sched/sched.h? [...]