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 ECDC1C02193 for ; Wed, 5 Feb 2025 00:56:25 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 76F0328000B; Tue, 4 Feb 2025 19:56:25 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 71E42280001; Tue, 4 Feb 2025 19:56:25 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5BC5B28000B; Tue, 4 Feb 2025 19:56:25 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 39296280001 for ; Tue, 4 Feb 2025 19:56:25 -0500 (EST) Received: from smtpin03.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id BD78047AC8 for ; Wed, 5 Feb 2025 00:56:24 +0000 (UTC) X-FDA: 83084075088.03.7013BDC Received: from mail-qv1-f47.google.com (mail-qv1-f47.google.com [209.85.219.47]) by imf25.hostedemail.com (Postfix) with ESMTP id D322FA0007 for ; Wed, 5 Feb 2025 00:56:22 +0000 (UTC) Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=joelfernandes.org header.s=google header.b=bKWQ06v3; spf=pass (imf25.hostedemail.com: domain of joel@joelfernandes.org designates 209.85.219.47 as permitted sender) smtp.mailfrom=joel@joelfernandes.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1738716982; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=9ij7khtd31hJX3bC+IFvIqGySEhuppZ7MucI5She8To=; b=x9gJU9CE3gfgtuKc7ICbt7DRSt76ITjSrY9kEHjUdCZujLIxN8DL1LspoKRjYdV6v2AOfC 5aO+jUJpleYn8dUagvlPNShgUm85sEkDmCH5GtWt3tq5trDsW9JeTxlPGh3vltHJCJcMtF E7Ury0AtsDGZ4B9JC0piMhV05kZMN5Y= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=joelfernandes.org header.s=google header.b=bKWQ06v3; spf=pass (imf25.hostedemail.com: domain of joel@joelfernandes.org designates 209.85.219.47 as permitted sender) smtp.mailfrom=joel@joelfernandes.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1738716982; a=rsa-sha256; cv=none; b=lpwnrqZTNhuqoS0ONyEPlqIfleMBqhNiTp9CF4wJ9DK+IH0du1UlYniHihpF7xYZxK6Yk8 7nutl5a9Z7xzMdfWqGT3Xp0AFPLQufgIwMZq+dRLoL9brcKVKhA8HrtZgaDnlWSxbK9Ogt biiqrovHouAtrv1/D44LW17FwcFqcbI= Received: by mail-qv1-f47.google.com with SMTP id 6a1803df08f44-6dcdd9a3e54so58140436d6.3 for ; Tue, 04 Feb 2025 16:56:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; t=1738716982; x=1739321782; darn=kvack.org; h=to:in-reply-to:cc:references:message-id:date:subject:mime-version :from:content-transfer-encoding:from:to:cc:subject:date:message-id :reply-to; bh=9ij7khtd31hJX3bC+IFvIqGySEhuppZ7MucI5She8To=; b=bKWQ06v3lCZRnps9K4l2FggE8LxLkEU9Oklg5im2BoMR21RdPk+KJ+1pSS3IITtwFy yjjQ+GqgNRllhCqn/PHoYbtlW8acySeqA09PLuqrPpFrOINTgExvNusdXO43/IRz444e WLxRPLt/IcEaXeKh7ortJG4wtS9B1xvIvISLs= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1738716982; x=1739321782; h=to:in-reply-to:cc:references:message-id:date:subject:mime-version :from:content-transfer-encoding:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=9ij7khtd31hJX3bC+IFvIqGySEhuppZ7MucI5She8To=; b=j3edfQ89YS9t3+UwMFMO/CiT89d/sh8Ps1Y5bsjPsvkF7PfgAilf1tq+opDYt8peDu Q+MTERUCyRNv9f671Jwta104O5RdvVxw+EPOotczX7OPNa75mH51iR20oHlo5fA0Q4Px Fenw+Q8StFQOiecO6KF8wfOOVfpyigq6GfEGIw6ZC7CLh+ostCoX8OgCYaOtJpJ8eQP+ y6GHR31rhNZbX4cHUnsa7qoNQO51CKPzgt0gpxbjdcn05YCjWavYmZzamnxTPoUauUxl cCdKsnSwFiWjE0+6VfRHnSI7y0IGDkUIyMVLjWCrv6VyddIMPO0mm0ndxJnrpoul21Pr +60w== X-Forwarded-Encrypted: i=1; AJvYcCUGK34WB3CvFdfZHgmsSOSZdnfq+TPIVuZl8bhxJnDCtwugzZNznld9+JrTmedZOzXiusFDsPApjw==@kvack.org X-Gm-Message-State: AOJu0YxjKq8ishdHYMhjDi78tMI0eLWa3/WzpUx+uyI629miKcXyuyru xHP5Nmn6wM7rh0U8xxhjHbtewYykPYZwbUlYPkRYxJm3BDQv6FChBKQXXvhYu+c= X-Gm-Gg: ASbGncvkaKTmxnsQeTf/zv7bZHkQqVdI0g9BtyAsklgA4uDnvGH29f8zJR2WR95p1DA wB/gqrsPBj+jA23/49mVEbThdUjg6V2+2sYN2rKU0HTNN2FD6Ml9tRB40391xV1XjYraXH3bvOA x/EHAcHvM3ua4k10UPgPEhgHDeZuAJ41bPyFKhPUQVjY2Cid4aBATXCn9nLiOrJ18ObODpicCr1 f00fqSJUwaydPgry9VqOOWzCmQF0I5MYtZd6mIYneDYUOFAvEfDJm+/QBmbm11CQ+gNx7AU469P DLcyfr8hE6pAdjo64Iw/iWOjy2BUzZo+Y5gLK2RUzO6wy0N74wa4QbWp0kDTThSRIKQEth6XfBD T X-Google-Smtp-Source: AGHT+IGIVVkrbX1KATNv8V2bEUqrsG5sfK5Qzl85BavL2KosHxDWEEmIEh2A+Ur9QNUp3/3BcOXuKA== X-Received: by 2002:a05:6214:d42:b0:6e2:4d70:1fbd with SMTP id 6a1803df08f44-6e42fb99504mr16023586d6.6.1738716981866; Tue, 04 Feb 2025 16:56:21 -0800 (PST) Received: from smtpclient.apple (c-73-251-172-144.hsd1.va.comcast.net. [73.251.172.144]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-6e2547f2bbesm67911656d6.12.2025.02.04.16.56.20 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 04 Feb 2025 16:56:20 -0800 (PST) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable From: Joel Fernandes Mime-Version: 1.0 (1.0) Subject: Re: [RFC][PATCH 1/2] sched: Extended scheduler time slice Date: Tue, 4 Feb 2025 19:56:09 -0500 Message-Id: <9DA1FAE6-A008-4785-BDF9-541457E29807@joelfernandes.org> References: Cc: Peter Zijlstra , Steven Rostedt , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Thomas Gleixner , Ankur Arora , Linus Torvalds , linux-mm@kvack.org, x86@kernel.org, Andrew Morton , luto@kernel.org, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, willy@infradead.org, mgorman@suse.de, jon.grimm@amd.com, bharata@amd.com, raghavendra.kt@amd.com, Boris Ostrovsky , Konrad Wilk , jgross@suse.com, Andrew.Cooper3@citrix.com, Vineeth Pillai , Suleiman Souhlal , Ingo Molnar , Mathieu Desnoyers , Clark Williams , bigeasy@linutronix.de, daniel.wagner@suse.com, Joseph Salisbury , broonie@gmail.com In-Reply-To: To: Prakash Sangappa X-Mailer: iPhone Mail (22B91) X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: D322FA0007 X-Stat-Signature: 8xnf3u11j7r17krytgeerbeftjqptss7 X-Rspam-User: X-HE-Tag: 1738716982-570155 X-HE-Meta: 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 o4OPHk5R 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000054, 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 Feb 4, 2025, at 5:44=E2=80=AFPM, Prakash Sangappa wrote: >=20 > =EF=BB=BF >=20 >> On Feb 1, 2025, at 10:11=E2=80=AFAM, Peter Zijlstra wrote: >>=20 >>> On Sat, Feb 01, 2025 at 07:47:32AM -0500, Steven Rostedt wrote: >>>=20 >>>=20 >>> On February 1, 2025 6:59:06 AM EST, Peter Zijlstra wrote: >>>=20 >>>> I still have full hate for this approach. >>>=20 >>> So what approach would you prefer? >>=20 >> The one that does not rely on the preemption method -- I think I posted >> something along those line, and someone else recently reposted something >> bsaed on it. >=20 > Here is the RFC I had sent that Peter is referring FWIW, I second the idea of a new syscall for this than (ab)using rseq and also independence from preemption method. I agree that something generic is better than relying on preemption method. thanks, - Joel > Tying things to the preemption method is absurdly bad design -- and I've >> told you that before. >>=20 >=20