From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH] ring: fix sc dequeue performance issue Date: Mon, 25 Jul 2016 07:54:01 -0700 (PDT) Message-ID: <2289614.DUoAzxZEto@xps13> References: <1469380060-26696-1-git-send-email-jerin.jacob@caviumnetworks.com> <2601191342CEEE43887BDE71AB97725836B817D7@irsmsx105.ger.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: "Ananyev, Konstantin" , dev@dpdk.org To: Jerin Jacob Return-path: Received: from mail-wm0-f50.google.com (mail-wm0-f50.google.com [74.125.82.50]) by dpdk.org (Postfix) with ESMTP id 21A583777 for ; Mon, 25 Jul 2016 16:54:02 +0200 (CEST) Received: by mail-wm0-f50.google.com with SMTP id o80so161001091wme.1 for ; Mon, 25 Jul 2016 07:54:02 -0700 (PDT) In-Reply-To: <2601191342CEEE43887BDE71AB97725836B817D7@irsmsx105.ger.corp.intel.com> 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" 2016-07-24 22:57, Ananyev, Konstantin: > From: Jerin Jacob [mailto:jerin.jacob@caviumnetworks.com] > > Use of rte_smb_wmb() instead of rte_smb_rmb() in sc dequeue function creates the additional overhead of waiting for all the STOREs to be > > completed to local buffer from ring buffer memory. The sc dequeue function demands only LOAD-STORE barrier where LOADs from ring > > buffer memory needs to be completed before tail pointer update. Changing to rte_smb_rmb() to enable the required LOAD-STORE barrier. > > > > Fixes: ecc7d10e448e ("ring: guarantee dequeue ordering before tail update") > > > > Signed-off-by: Jerin Jacob > > Acked-by: Konstantin Ananyev Applied, thanks for the quick reaction