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 2EC84C25B0C for ; Mon, 8 Aug 2022 11:43:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242214AbiHHLnE (ORCPT ); Mon, 8 Aug 2022 07:43:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46768 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234041AbiHHLm5 (ORCPT ); Mon, 8 Aug 2022 07:42:57 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3C68913D47; Mon, 8 Aug 2022 04:42:56 -0700 (PDT) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1659958974; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=hxz5dJVKmW1JnSAUI9gZLzzxb4GJLXHvw8kFzNX5wd8=; b=P78VbJbhlFpuaRdoY0rRdSHkrmwFXjGAEcXUPHpzToAtrbtJ6quuzWFygkHUaZ/YKn23iH m3hOn3lyMu4XvNbNIm9x3rjaezSOFFoCQryOSpvkCmBS5sPR0foKFa4ImSNp13avNWIMU1 NapzLVC2AF45f6exFgL5eDAE/ElbAjlIlHQZ6ZnvDw2s125p9Q5/iSnf9WaDQ4Z2wswrDZ i1+u07p8TefWOpGDTxKLVKSk8cV1nbwFtPw/jW6vlogwWf4JNNj6F5755wcIPgACCA5M+s 5eytNX+JviKrGszvF3B3CaReaRI5fqiwy/YRzW/zQen+EOXXnlykC1XYrAiyqQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1659958974; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=hxz5dJVKmW1JnSAUI9gZLzzxb4GJLXHvw8kFzNX5wd8=; b=m4hEevSGgE4U5+5naPIR6UURVhQTYZGLM8RMnmVGdjavu7mQqxWW7wFigJsRGGYEB+XDxD phOWpBmu6yN2RMBg== To: Yury Norov , linux-kernel@vger.kernel.org, Alexander Lobakin , Alexei Starovoitov , Alexey Klimov , Andrew Morton , Andrii Nakryiko , Andy Shevchenko , Ben Segall , Christoph Lameter , Dan Williams , Daniel Borkmann , Daniel Bristot de Oliveira , Dennis Zhou , Dietmar Eggemann , Eric Dumazet , Frederic Weisbecker , Guenter Roeck , Ingo Molnar , Isabella Basso , John Fastabend , Josh Poimboeuf , Juergen Gross , Juri Lelli , KP Singh , Kees Cook , Martin KaFai Lau , Mel Gorman , Miroslav Benes , Nathan Chancellor , "Paul E . McKenney" , Peter Zijlstra , Randy Dunlap , Rasmus Villemoes , Sebastian Andrzej Siewior , Song Liu , Steven Rostedt , Tejun Heo , Valentin Schneider , Vincent Guittot , Vlastimil Babka , Yonghong Song , Yury Norov , linux-mm@kvack.org, netdev@vger.kernel.org, bpf@vger.kernel.org Subject: Re: [PATCH 11/16] time: optimize tick_check_preferred() In-Reply-To: <87fsi9rcxu.ffs@tglx> References: <20220718192844.1805158-1-yury.norov@gmail.com> <20220718192844.1805158-12-yury.norov@gmail.com> <87fsi9rcxu.ffs@tglx> Date: Mon, 08 Aug 2022 13:42:54 +0200 Message-ID: <87czdbq7up.ffs@tglx> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Aug 06 2022 at 10:30, Thomas Gleixner wrote: > On Mon, Jul 18 2022 at 12:28, Yury Norov wrote: > >> tick_check_preferred() calls cpumask_equal() even if >> curdev->cpumask == newdev->cpumask. Fix it. > > What's to fix here? It's a pointless operation in a slow path and all > your "fix' is doing is to make the code larger. In fact cpumask_equal() should have the ptr1 == ptr2 check, so you don't have to add it all over the place. Thanks, tglx