From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933573AbcIOLkK (ORCPT ); Thu, 15 Sep 2016 07:40:10 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:37958 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1763811AbcIOLkJ (ORCPT ); Thu, 15 Sep 2016 07:40:09 -0400 Date: Thu, 15 Sep 2016 04:40:05 -0700 From: Christoph Hellwig To: Wouter Verhelst Cc: Alex Bligh , Josef Bacik , "nbd-general@lists.sourceforge.net" , "linux-kernel@vger.kernel.org" , linux-block@vger.kernel.org, Markus Pargmann , kernel-team@fb.com Subject: Re: [Nbd] [RESEND][PATCH 0/5] nbd improvements Message-ID: <20160915114005.GC23259@infradead.org> References: <1473369130-22986-1-git-send-email-jbacik@fb.com> <20160909200203.phhvodsfs7ymukfp@grep.be> <20160915104935.ohuwgq2chsedz6fl@grep.be> <27B346AF-F144-4770-BE38-446A66E71326@alex.org.uk> <20160915112936.vb7zxe7k6rvczosg@grep.be> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160915112936.vb7zxe7k6rvczosg@grep.be> User-Agent: Mutt/1.6.1 (2016-04-27) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 15, 2016 at 01:29:36PM +0200, Wouter Verhelst wrote: > Yes, and that is why I was asking about this. If the write barriers > are expected to be shared across connections, we have a problem. If, > however, they are not, then it doesn't matter that the commands may be > processed out of order. There is no such thing as a write barrier in the Linux kernel. We'd much prefer protocols not to introduce any pointless synchronization if we can avoid it.