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[23.128.96.18]) by mx.google.com with ESMTP id re2si3050817ejb.407.2021.05.12.04.01.39; Wed, 12 May 2021 04:02:12 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=casper.20170209 header.b=gY2AFbr2; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230102AbhELLB4 (ORCPT + 99 others); Wed, 12 May 2021 07:01:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230035AbhELLB4 (ORCPT ); Wed, 12 May 2021 07:01:56 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6DF2FC061574 for ; Wed, 12 May 2021 04:00:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=+2JqDURQ4NfYeJG41cbfu5+yywBSW9JE5vYZt2sYJm8=; b=gY2AFbr23XMuHDYQfvAsDNHHIJ 1wwg00mKczf72UDNWCKzlr+2UttqeaQciFFEHXEEcdAEOorpg/uSU4szstKBYs40mc8UH3bxR7nNo GCK/c+AG7eaAa1oXowuc+glaDe7ntBl80J8ko61DOGABbRup6JzFbYWXd/NGJ1SC7myj+QD22wSnO 4IdeufEWe9fYTgKGiWk9E/DBRhqlgp8jzAoxcTL+2heD238cJSrgrNQMu0LEkw5EIYy+oKiMJiMaQ v2NOPkv3KWodz3p11R7R2sQC2iefo+HENV+w018Jt/TCY3zXwdPEd2uaAkCJIw/OvCnim/2p1R2Hi fZrq6Eiw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1lgmb1-008CXB-Oc; Wed, 12 May 2021 11:00:16 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 01D79300242; Wed, 12 May 2021 13:00:06 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id D65B820B5CA9B; Wed, 12 May 2021 13:00:06 +0200 (CEST) Date: Wed, 12 May 2021 13:00:06 +0200 From: Peter Zijlstra To: Valentin Schneider Cc: linux-kernel@vger.kernel.org, mingo@kernel.org, tglx@linutronix.de, bristot@redhat.com, yejune.deng@gmail.com Subject: Re: [PATCH 0/2] sched: Address idle task vs pcpu kthread checks Message-ID: References: <20210510151024.2448573-1-valentin.schneider@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210510151024.2448573-1-valentin.schneider@arm.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 10, 2021 at 04:10:22PM +0100, Valentin Schneider wrote: > Note: I remember seeing some patch(es) from Peter tackling this exact > problem, but I couldn't find them again. Found it (by accident), yours is nicer though :-) > Valentin Schneider (1): > sched: Make the idle task quack like a per-CPU kthread > > Yejune Deng (1): > lib/smp_processor_id: Use is_percpu_thread() instead of > nr_cpus_allowed > > include/linux/kthread.h | 2 ++ > kernel/kthread.c | 30 ++++++++++++++++++------------ > kernel/sched/core.c | 21 +++++++++++++++------ > lib/smp_processor_id.c | 6 +----- > 4 files changed, 36 insertions(+), 23 deletions(-) Thanks!