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[209.132.180.67]) by mx.google.com with ESMTP id l1si6739692ejr.246.2019.09.30.04.55.09; Mon, 30 Sep 2019 04:55:34 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=fail header.i=@infradead.org header.s=bombadil.20170209 header.b=TSA4rtOg; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729740AbfI3Lyu (ORCPT + 99 others); Mon, 30 Sep 2019 07:54:50 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:57260 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728214AbfI3Lyu (ORCPT ); Mon, 30 Sep 2019 07:54:50 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=y2KGBY7QYCvtjU9Jo3p22YeQoSiwLIAWWQXcVGO2Rr4=; b=TSA4rtOgRCyhAMQuiIesgTfOT 1UYr4XYXycgOZud28qmBjcP3LdZ4+MzJ2oi0gDD/LXHWg4WBo3q762O2z2QIfJBYeW21tCb9cJLLY 5UFunauOU67UdvNUMu3gfJ9BhPI9w9SIrQ4zV2BUA+dzPHVfthYho9YAkw+S+uPVJY3VVYqRFAjjU zdSRlwZWIjPAXb0V6Kb/nDe9g3nNzKwSbBaKCyq7e4n1cd/paUizWDcaXglGJW3W65wVn0t01ZGAg 5qv16YPUk5WcMy2eFGrySTr7DjLg6sY8wK6c6xLl50Et4qvC47HodAErucSZDdxPSo9COlQKGvnhc FdHa0BATw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.2 #3 (Red Hat Linux)) id 1iEuGI-0005xn-NC; Mon, 30 Sep 2019 11:54:42 +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 3BA853056B6; Mon, 30 Sep 2019 13:53:52 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 2A96D265317EF; Mon, 30 Sep 2019 13:54:40 +0200 (CEST) Date: Mon, 30 Sep 2019 13:54:40 +0200 From: Peter Zijlstra To: Nick Desaulniers Cc: Andrea Parri , David Howells , Linus Torvalds , Will Deacon , "Paul E. McKenney" , Mark Rutland , Linux List Kernel Mailing , linux-fsdevel , jose.marchesi@oracle.com Subject: Re: Do we need to correct barriering in circular-buffers.rst? Message-ID: <20190930115440.GC4581@hirez.programming.kicks-ass.net> References: <25289.1568379639@warthog.procyon.org.uk> <28447.1568728295@warthog.procyon.org.uk> <20190917170716.ud457wladfhhjd6h@willie-the-truck> <15228.1568821380@warthog.procyon.org.uk> <5385.1568901546@warthog.procyon.org.uk> <20190923144931.GC2369@hirez.programming.kicks-ass.net> <20190927095107.GA13098@andrea> <20190927124929.GB4643@worktop.programming.kicks-ass.net> <20190930093352.GM4553@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190930093352.GM4553@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 Mon, Sep 30, 2019 at 11:33:52AM +0200, Peter Zijlstra wrote: > Like I said before, something like: "disallowing store hoists over control > flow depending on a volatile load" would be sufficient I think. We need to add 'control flow depending on an inline-asm' to that. We also very much use that.