From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerin Jacob Subject: Re: [PATCH] lib: change rte_ring dequeue to guarantee ordering before tail update Date: Sat, 23 Jul 2016 11:35:16 +0530 Message-ID: <20160723060515.GA13747@localhost.localdomain> References: <20160715043951.32040-1-juhamatti.kuusisaari@coriant.com> <2601191342CEEE43887BDE71AB97725836B7E32F@irsmsx105.ger.corp.intel.com> <14017551.U6D1dIIx0P@xps13> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: Juhamatti Kuusisaari , , "Ananyev, Konstantin" To: Thomas Monjalon Return-path: Received: from NAM02-BL2-obe.outbound.protection.outlook.com (mail-bl2nam02on0081.outbound.protection.outlook.com [104.47.38.81]) by dpdk.org (Postfix) with ESMTP id 73482559C for ; Sat, 23 Jul 2016 08:05:42 +0200 (CEST) Content-Disposition: inline In-Reply-To: <14017551.U6D1dIIx0P@xps13> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On Thu, Jul 21, 2016 at 11:26:50PM +0200, Thomas Monjalon wrote: > > > Consumer queue dequeuing must be guaranteed to be done fully before the tail is updated. This is not guaranteed with a read barrier, > > > changed to a write barrier just before tail update which in practice guarantees correct order of reads and writes. > > > > > > Signed-off-by: Juhamatti Kuusisaari > > > > Acked-by: Konstantin Ananyev > > Applied, thanks There was ongoing discussion on this http://dpdk.org/ml/archives/dev/2016-July/044168.html This change may not be required as it has the performance impact.