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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C1687CE79A9 for ; Tue, 19 Sep 2023 19:53:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232845AbjISTxQ (ORCPT ); Tue, 19 Sep 2023 15:53:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34562 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232503AbjISTxP (ORCPT ); Tue, 19 Sep 2023 15:53:15 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 53028EA; Tue, 19 Sep 2023 12:53:09 -0700 (PDT) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1695153187; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Z6MR2qg7K68Ikjp5YKoXbgk+KfdFV5OyH5X+XZI8Hys=; b=mOb/eNZUdC0Wj3l6CxvHBXP8mwAJuYFnOVgDDGyXCVGfE9qGC/lTBJMdjrY5OSdh22ztlP 0pmpPVdeREqTDHGNAEeNvS1DieP+VUS9naCyvjQLxXHFNIP7ZMrmMpAb/G7OBUsq8HkoXh Cf2s4EE0LCAMh9WCn8yLJcvMdWe4fgVs+RUHjyvJHQe1wc5lXIfPpDuHsf3M3vaqIXgsMB c1zOM7RIRJi9+pTWs8ld1rHuTaEkuhd5s6SL99eLVBOi2BmjT9kDN+s+XFm70ynEg0DH68 vw1rGuAKizG2OM9QTS2IvcNs1PTtQ9WH7K2vOYlgdiHCWVPYnna48qBKdgNrMA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1695153187; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Z6MR2qg7K68Ikjp5YKoXbgk+KfdFV5OyH5X+XZI8Hys=; b=L3qg/U5CuhkLaMEQDfDZJ0Bp292wap1ObMBS0Fd+vVbQEdDuD8p1gEYpDfgtKABKvVsKv+ 70jMfd8FpBl2jmDQ== To: Linus Torvalds , Steven Rostedt Cc: John Paul Adrian Glaubitz , Peter Zijlstra , Matthew Wilcox , Ankur Arora , linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org, akpm@linux-foundation.org, luto@kernel.org, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, mgorman@suse.de, jon.grimm@amd.com, bharata@amd.com, raghavendra.kt@amd.com, boris.ostrovsky@oracle.com, konrad.wilk@oracle.com, jgross@suse.com, andrew.cooper3@citrix.com, Geert Uytterhoeven , linux-m68k@lists.linux-m68k.org, Richard Weinberger , Anton Ivanov , Johannes Berg , linux-um@lists.infradead.org, Brian Cain , linux-hexagon@vger.kernel.org, Richard Henderson , Ivan Kokshaysky , Matt Turner , linux-alpha@vger.kernel.org Subject: Re: Arches that don't support PREEMPT In-Reply-To: References: <87zg1u1h5t.fsf@oracle.com> <20230911150410.GC9098@noisy.programming.kicks-ass.net> <87h6o01w1a.fsf@oracle.com> <20230912082606.GB35261@noisy.programming.kicks-ass.net> <87cyyfxd4k.ffs@tglx> <87led2wdj0.ffs@tglx> <0e69f7df80dc5878071deb0d80938138d19de1d1.camel@physik.fu-berlin.de> <20230919134218.GA39281@noisy.programming.kicks-ass.net> <87pm2eui95.ffs@tglx> <20230919143816.1741760a@gandalf.local.home> Date: Tue, 19 Sep 2023 21:53:07 +0200 Message-ID: <87jzsmueho.ffs@tglx> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 19 2023 at 11:52, Linus Torvalds wrote: > On Tue, 19 Sept 2023 at 11:37, Steven Rostedt wrote: >> >> We could simply leave the cond_resched() around but defined as nops for >> everything but the "nostalgia club" to keep them from having any regressions. > > I doubt the nostalgia club cares about some latencies (that are > usually only noticeable under extreme loads anyway). > > And if they do, maybe that would make somebody sit down and look into > doing it right. > > So I think keeping it around would actually be both useless and > counter-productive. Amen to that.