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[23.128.96.18]) by mx.google.com with ESMTP id g7si3378350ejf.410.2020.04.22.05.27.24; Wed, 22 Apr 2020 05:27:47 -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=@kernel.org header.s=default header.b=JL01+7Ny; 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; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726319AbgDVM0f (ORCPT + 99 others); Wed, 22 Apr 2020 08:26:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:39216 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725810AbgDVM0e (ORCPT ); Wed, 22 Apr 2020 08:26:34 -0400 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D498620882; Wed, 22 Apr 2020 12:26:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587558394; bh=WoG2dRF24011ASSJYkMybNHc6GOGg8Zw81SdJa7uWmA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=JL01+7NyGCwL4SlN73HMZYvZs4+e0Kpgw5i4ViVCGIdgw9rRAAkJE1o9XG9xEXdzs bmrk6baGNDggzYYVj4vUQIpIcMlF4kuKxlK/2MGRUlIeJLKFvmKPfouVDoupzAal9P UJoM+AYccAuas6549mdjRFCs08BhdDEiaOjCYUxY= Date: Wed, 22 Apr 2020 13:26:27 +0100 From: Will Deacon To: Peter Zijlstra Cc: Linus Torvalds , Linux Kernel Mailing List , linux-arch , Android Kernel Team , Mark Rutland , Michael Ellerman , Segher Boessenkool , Christian Borntraeger , Luc Van Oostenryck , Arnd Bergmann , Peter Oberparleiter , Masahiro Yamada , Nick Desaulniers Subject: Re: [PATCH v4 00/11] Rework READ_ONCE() to improve codegen Message-ID: <20200422122626.GA676@willie-the-truck> References: <20200421151537.19241-1-will@kernel.org> <20200422081838.GA29541@willie-the-truck> <20200422113721.GA20730@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200422113721.GA20730@hirez.programming.kicks-ass.net> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 22, 2020 at 01:37:21PM +0200, Peter Zijlstra wrote: > On Wed, Apr 22, 2020 at 09:18:39AM +0100, Will Deacon wrote: > > On Tue, Apr 21, 2020 at 11:42:56AM -0700, Linus Torvalds wrote: > > > On Tue, Apr 21, 2020 at 8:15 AM Will Deacon wrote: > > > > > > > > It's me again. This is version four of the READ_ONCE() codegen improvement > > > > patches [...] > > > > > > Let's just plan on biting the bullet and do this for 5.8. I'm assuming > > > that I'll juet get a pull request from you? > > > > Sure thing, thanks. I'll get it into -next along with the arm64 bits for > > 5.8, but I'll send it as a separate pull when the time comes. I'll also > > include the sparc32 changes because otherwise the build falls apart and > > we'll get an army of angry robots yelling at us (they seem to form the > > majority of the active sparc32 user base afaict). > > So I'm obviously all for these patches; do note however that it collides > most mighty with the KCSAN stuff, which I believe is still pending. That stuff has been pending for the last two releases afaict :/ Anyway, I'm happy to either provide a branch with this series on, or do the merge myself, or send this again based on something else. What works best for you? The only thing I'd obviously like to avoid is tightly coupling this to KCSAN if there's a chance of it missing the merge window again. Cheers, Will