From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2892BC25B76 for ; Sat, 1 Jun 2024 22:31:25 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6BEFB6B0098; Sat, 1 Jun 2024 18:31:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 66F6D6B009A; Sat, 1 Jun 2024 18:31:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 50FBD6B009E; Sat, 1 Jun 2024 18:31:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 32AD66B0098 for ; Sat, 1 Jun 2024 18:31:24 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id B6AF01C1D04 for ; Sat, 1 Jun 2024 22:31:23 +0000 (UTC) X-FDA: 82183767246.09.5A5639A Received: from mail-wm1-f41.google.com (mail-wm1-f41.google.com [209.85.128.41]) by imf02.hostedemail.com (Postfix) with ESMTP id CC66780009 for ; Sat, 1 Jun 2024 22:31:21 +0000 (UTC) Authentication-Results: imf02.hostedemail.com; dkim=pass header.d=layalina-io.20230601.gappssmtp.com header.s=20230601 header.b=Hwtsk6pC; dmarc=none; spf=pass (imf02.hostedemail.com: domain of qyousef@layalina.io designates 209.85.128.41 as permitted sender) smtp.mailfrom=qyousef@layalina.io ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1717281081; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=qZbo561XfWIHgBvmySekggiN2gQefSMXY05ZVlA1bQk=; b=wpOXo9o5IgHaVKdC+DZQdTNVjGHRwX5F/22CDr2WgIDsIX6y3+dkghzmCVa6LsWNdWLqLd ZHWlTOtBdhBVCLNDyZOU7hCc3wgSeNJ9A4FSC0FmKEmfGZV02fRO5nDevoEp7QvLLr6en2 xSZvZT7yYcZGuPdWsrSwcDOMKO24JXM= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1717281081; a=rsa-sha256; cv=none; b=4zNemslo/sc3P3DM8LlVkqa8itp0Ghka3BSUjilSugM3Td8jdBSZbRjzCc+0FHjMSgZp6Z XzcXT3a1jfLaF8wXEv9JWPtqSn7ybVi88Z5NXqoBsdP9ez+ghbGtaftGW/bBBa+ohGIrrF r/IVoW6hIPhimp5HCGz3jSzzeW2wENo= ARC-Authentication-Results: i=1; imf02.hostedemail.com; dkim=pass header.d=layalina-io.20230601.gappssmtp.com header.s=20230601 header.b=Hwtsk6pC; dmarc=none; spf=pass (imf02.hostedemail.com: domain of qyousef@layalina.io designates 209.85.128.41 as permitted sender) smtp.mailfrom=qyousef@layalina.io Received: by mail-wm1-f41.google.com with SMTP id 5b1f17b1804b1-421140314d5so29261375e9.0 for ; Sat, 01 Jun 2024 15:31:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=layalina-io.20230601.gappssmtp.com; s=20230601; t=1717281080; x=1717885880; darn=kvack.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=qZbo561XfWIHgBvmySekggiN2gQefSMXY05ZVlA1bQk=; b=Hwtsk6pCZKKSiXbpiWC0C9YJEMLX2mDnMZAlmU204XwwwUSjnZnvb7nVXSJOFblSQK CX6HhM4/n2LPsmvh2GCvDR66zLNWFaFpGNOoDwbCxWIerbbQPz/KggGEifvXkMLdTp+x Sso7UEFizorG2Q2K551ot0Q8GC+cd8kJHRREJPlpJeuXdnBfpzdYBcqB/TjtF9NCsgdm j+b+11hgOPXBMt1wBUCIP66u8OdVsj658fxSRmxTRA8EEAs2lchfC2JAcb804+61IQKM 5ZbJRAVVuYd2dMZvSQ6WBg7r63KDkNQG74L0MtHl6VTG36fOr7j+HPQGuUZsVqrscTrC CpHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1717281080; x=1717885880; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=qZbo561XfWIHgBvmySekggiN2gQefSMXY05ZVlA1bQk=; b=h3ijF006BYLQEuKVFbRv7vJn9H+M1TgWdv/gbCKPKbX4w+hvoklUdAeby5gZTOMRlb HA1dgedJ1PR2u3mCR6SC1eDnY/WXi4AtBFm7++McTWz0ep8fjFbIybiaEnTOX9dM+qVA SUcrhFVppPMjvZhzrzYLF7BnuWBf+qAksMxMVQoLWTI2tx8KglOL2/w+fpxjwXLl8JCb KLVXkz1Fw3ujcIKHp2ngoNrI2/fLk/psWl0z0JtfBMO8SqCU6TdZ6Ksfz2eL5oZmo4ki zytCwF5cDzxPOKzj/VExPnPfnDPln4A1ssLYbHadpWqSvw6Zxb7poF709LHOEDP9yfxK fgBA== X-Forwarded-Encrypted: i=1; AJvYcCXywsKjuVCRCuuan4v0eQWmgLlohX609wfa+EtWCjvUR1Tt+N1DLsPNnzZCagJvAqgV4V2YhAFgWesX81JS+Wmp/Y0= X-Gm-Message-State: AOJu0Yzt/DQWbSmUKofQ+QL/HfAy1UjagJdRea/W8bYxQr2E5BY0LGS2 l7+I1TDMXi/fsFiUX0UpOkvfXowrziOns27GU67NZNDuJH00rN1VlkYhLYt72iE= X-Google-Smtp-Source: AGHT+IHfbQ16/ESCbDfdhRvNrgQE37C2AAjcr2HQe1Exqfame6Csvm3T9BWb8bjJaVLiJ2lhT2dYFQ== X-Received: by 2002:a05:600c:a4b:b0:421:1165:f240 with SMTP id 5b1f17b1804b1-4212e0bfd91mr46367175e9.36.1717281080159; Sat, 01 Jun 2024 15:31:20 -0700 (PDT) Received: from airbuntu (host81-157-90-255.range81-157.btcentralplus.com. [81.157.90.255]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4212f05157esm53941435e9.20.2024.06.01.15.31.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 01 Jun 2024 15:31:19 -0700 (PDT) Date: Sat, 1 Jun 2024 23:31:18 +0100 From: Qais Yousef To: Sebastian Andrzej Siewior Cc: Ingo Molnar , Peter Zijlstra , Juri Lelli , Steven Rostedt , Vincent Guittot , Daniel Bristot de Oliveira , Thomas Gleixner , Alexander Viro , Christian Brauner , Andrew Morton , Jens Axboe , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-mm@kvack.org, Phil Auld Subject: Re: [PATCH v2] sched/rt: Clean up usage of rt_task() Message-ID: <20240601223118.zjhp7pgk3wb32abv@airbuntu> References: <20240515220536.823145-1-qyousef@layalina.io> <20240521110035.KRIwllGe@linutronix.de> <20240527172650.kieptfl3zhyljkzx@airbuntu> <20240529082912.gPDpgVy3@linutronix.de> <20240529103409.3iiemroaavv5lh2p@airbuntu> <20240529105528.9QBTCqCr@linutronix.de> <20240530111044.d4jegeiueizvdjrg@airbuntu> <20240531063016.OCMg21Uq@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20240531063016.OCMg21Uq@linutronix.de> X-Stat-Signature: 8rrqj5w5shx5n74x16sgksu1zyhm3sni X-Rspamd-Queue-Id: CC66780009 X-Rspam-User: X-Rspamd-Server: rspam01 X-HE-Tag: 1717281081-603391 X-HE-Meta: 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 6VttfQkb 3TEz3j54F+pFtRQ+NwJaZ79agSclmf9l8yU+CNK1DWS4leyqZg9WmtoJEdeffTgbzRV64biIz6mAYcHdrebiVVK0S3jlcrXClX53avY351kqSFdocB7Ii052homaSLEpbT/II9K0tgHLuyL4Yr7SxZ89CYfY884cAFlGdrpQDv4IxRie+ERHJjTWj4pWf9d9rQYu6c9urQJ2WTigWMH/AD/+Uy2lsno92ECI+YKtZpRprnDnKGmHpMFTmg4AiXdaTLGygOYf1gUnnDpL4wUsP3HcvWgaSguQm1//5mw0onEhc+NvyxPE4Coep8FlY2S5NnzjFxUgnOgMrcl6TSZtXYPNGEm5zpuGcJvGLO24BxCvCEq6ijKkBs+biDzpjTqpt/K9yZDn8jesRfxRQ9BtJAsZQn6ilXbMaPbR+ve7bv7yMH+/mX156h0HueRIO9D1qFL+U X-Bogosity: Ham, tests=bogofilter, spamicity=0.000009, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 05/31/24 08:30, Sebastian Andrzej Siewior wrote: > On 2024-05-30 12:10:44 [+0100], Qais Yousef wrote: > > > This is not consistent because IMHO the clock setup & slack should be > > > handled equally. So I am asking the sched folks for a policy and I am > > > leaning towards looking at task-policy in this case instead of prio > > > because you shouldn't do anything that can delay. > > > > Can't we do that based on is_soft/is_hard flag in hrtimer struct when we apply > > the slack in hrtimer_set_expires_range_ns() instead? > > We need to decide on a policy first. > You don't want to add overhead on each invocation plus some in-kernel > ask for delta. ->is_soft is not a good criteria. The suggestion was not to check policy or priority but dictate the behavior based on hrtimer properties set at init. Which agrees with your thinking. I think the check for policy at init to enforce a behavior is borderline hack by the way and better to get an explicit request from a task and let the HRTIMER comply adequately without checking for policies anywhere. Whether this property should be inherited or not is a good question and I think is the policy you're after here. Proxy Execution would probably handle all this inheritance problems transparently, so we need not think much about it if we agree proxy execution is the way to deal with all those inheritance problems. There are always exceptions though.. So worth a think. I'll drop this patch as this discussion has diverged to something else now. I'll leave this here until others get a chance to comment with their views too. Cheers -- Qais Yousef