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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 X-Rspam-User: X-Stat-Signature: o5umrtm7hgq8yu1aafwd53oyyffmyydd X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 1857C1C0030 X-HE-Tag: 1695153189-795146 X-HE-Meta: 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 BAx2WpMh ctkzpwh2m3zCI265vRmND/O5mdNvb9HjuwHkKT2tyC0PnzJ649ukjj+qkFEUrgmeQTDiGMAuBeE/8h5VVEq/SfSrm+YowDSkOSzjGgjSYs36Zo0M= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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.