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[2620:137:e000::1:20]) by mx.google.com with ESMTP id p1-20020a17090a868100b00219fda33b30si3070777pjn.108.2022.12.23.03.05.56; Fri, 23 Dec 2022 03:06:05 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=ka70E5tl; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236035AbiLWKre (ORCPT + 65 others); Fri, 23 Dec 2022 05:47:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60072 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229996AbiLWKrc (ORCPT ); Fri, 23 Dec 2022 05:47:32 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1BBA92EFA0; Fri, 23 Dec 2022 02:47:32 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id C4A3EB82047; Fri, 23 Dec 2022 10:47:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 24284C433EF; Fri, 23 Dec 2022 10:47:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1671792449; bh=ex9tUFVzc3QpNndS9PcMpEixDO6l3s3FIt9ke6UH+ZE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ka70E5tliEuEJuR8BXOIfpsdrB8M3Ypxmi8HmSwwAgr+652FYThaXtjy9LMDQ89n+ 2n5/b2Ca34ShyUWa8l8C6bbRPwSt6koWzxNoTd860eZcPF6tdSZ87LxEnBwGXevYhD lGioDkksupu6H8Tdi+tNbaXYi2XTogjCsFLJT3rDihEQ+W7v+PwKD+9bGbUANus4iV a8ALJKh39Q7v00Hg5RhZVzrxj4L1ouW1ktcyYown5kKjg6Qo9zPm34rON2gYICJVqO cO162Ao1DpYeAK4iUGx3W0N+rToXUhIr1d6g9NEAeS/8LbF2EC1AVaquHZ79Ad3dVY IIABKhvvgyR2A== Date: Fri, 23 Dec 2022 11:47:24 +0100 From: Christian Brauner To: Uros Bizjak Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Alexander Viro Subject: Re: [PATCH] posix_acl: Use try_cmpxchg in get_acl Message-ID: <20221223104724.uurfko6bqzpjv5n5@wittgenstein> References: <20221221193540.10078-1-ubizjak@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20221221193540.10078-1-ubizjak@gmail.com> X-Spam-Status: No, score=-7.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_HI, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 21, 2022 at 08:35:40PM +0100, Uros Bizjak wrote: > Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old > in get_acl. x86 CMPXCHG instruction returns success in ZF flag, > so this change saves a compare after cmpxchg (and related move > instruction in front of cmpxchg). > > No functional change intended. > > Signed-off-by: Uros Bizjak > Cc: Christian Brauner > Cc: Alexander Viro > --- Looks ok to me. But it's not urgent so I'll circle back to this post -rc1. Thanks! Christian