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 X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65735C433DB for ; Thu, 7 Jan 2021 11:20:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 159D8221E9 for ; Thu, 7 Jan 2021 11:20:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726436AbhAGLUY (ORCPT ); Thu, 7 Jan 2021 06:20:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55070 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726229AbhAGLUY (ORCPT ); Thu, 7 Jan 2021 06:20:24 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 969B8C0612F4; Thu, 7 Jan 2021 03:19:43 -0800 (PST) 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=OaPgUI5aCCYZQI5vszvvf5IbsCgMfnpkhzevE0JkHCg=; b=IqMv68P+0jpey0fzZ2N7VF5J0c +L6n+CHvNdfG/kIP9nSZwYPxAJ8845r1RWz+LYvGkHdRK4gsZOa8Kdduzx3/MzGNN9F/cmC3hY9Xh H/k0ui/EotgpzaVCqeDsSVJDevd+hbrEf1roXh7bNuatFoRaR1XUFHsUfuJMtJBMEKL0SZ1RwD3tC +FvDUxIKEkVBUystdkRrTilwb3iJcNGpE2v1lP108klPNUzFh12n0aQG1W14x/rZDgTXhJ6BHr5CZ t4lp82RVBz6/Qw1NrnFqHYha8VShHtXEsgcY61ub/lWvzEFFk4yCrrnp80NGV8SI1M41GYbKaiQzk QGBk9MuA==; 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 1kxTJr-003JrH-MO; Thu, 07 Jan 2021 11:19:16 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 996513060AE; Thu, 7 Jan 2021 12:19:04 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 7F47220164737; Thu, 7 Jan 2021 12:19:04 +0100 (CET) Date: Thu, 7 Jan 2021 12:19:04 +0100 From: Peter Zijlstra To: guoren@kernel.org Cc: arnd@arndb.de, linux-kernel@vger.kernel.org, linux-csky@vger.kernel.org, linux-arch@vger.kernel.org, Guo Ren , Arnd Bergmann , "Paul E . McKenney" Subject: Re: [PATCH v2 1/5] csky: Remove custom asm/atomic.h implementation Message-ID: References: <1608478763-60148-1-git-send-email-guoren@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1608478763-60148-1-git-send-email-guoren@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-csky@vger.kernel.org On Sun, Dec 20, 2020 at 03:39:19PM +0000, guoren@kernel.org wrote: > From: Guo Ren > > Use generic atomic implementation based on cmpxchg. So remove csky > asm/atomic.h. Clarification would be good. Typically cmpxchg() loops perform sub-optimal on LL/SC architectures, due to the double loop construction.