From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yb0-f182.google.com (mail-yb0-f182.google.com [209.85.213.182]) by dpdk.org (Postfix) with ESMTP id 495CE10DCA for ; Fri, 23 Dec 2016 02:42:24 +0100 (CET) Received: by mail-yb0-f182.google.com with SMTP id w19so15805060ybb.2 for ; Thu, 22 Dec 2016 17:42:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=EsKTWr9hoNkoWFbj0J4lw/jZngAs8EbbMf/Eg/cWd7Y=; b=ckdIHmFx5AuSh91DJLTHe3TbbFfnuEqxL6AR6TTmavko3mCm8EPl7vtvuSgy+bY/66 /42+WoFSiXDYndIVCvSoTPGq15XPxjAMI/kE+JECqijI+ysqcIqr1OjeQtE9f6thd1iT lKzE5PaBstB7D/UgB0mF1yrxqiUyuxXxnEQos= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=EsKTWr9hoNkoWFbj0J4lw/jZngAs8EbbMf/Eg/cWd7Y=; b=DFwQkeeF/43TVqteneoVcpSAR1dRQjU7xXN+uDPBs/mlTaX9nLIvjpVCdT1VSfyM6L ZLkibLDu49E3NeDx3wA9xrmQXk5BzI3zpzM6z7weU7tnrPmnZkCsDCqnPeLbyoM0HQr8 PjfmzW4Q6GPkoc+OUZ/lVhzCH+sIf4JZ9SyvWyGD7WvkVwqqp+izya1vtSrSXYmeknvd I7giAqa+1mSeXvfLJ4X0Jv3QID68qgI7t+KcEqmfUoq9C2P/CEEJ6c7GytcQ/VRvI4Ww X/8oNgnBoQYkrCZIub0rbhbehmIENpM8XX3Le7YpmKDlPDeOfshr8LZItcccvRlBB0BP gvwQ== X-Gm-Message-State: AIkVDXKDbizH/nzFRY87vrZEiVC+NPvcmhO+xPlH6vXimzi70qCSMSFWz2FqoIVjkEt068QGzOb5o8WhSChTvKaI X-Received: by 10.37.178.23 with SMTP id i23mr8690352ybj.29.1482457343696; Thu, 22 Dec 2016 17:42:23 -0800 (PST) MIME-Version: 1.0 Received: by 10.37.193.131 with HTTP; Thu, 22 Dec 2016 17:42:23 -0800 (PST) In-Reply-To: <20161222123614.GA8868@santosh-Latitude-E5530-non-vPro> References: <1481680558-4003-1-git-send-email-jerin.jacob@caviumnetworks.com> <1481680558-4003-24-git-send-email-jerin.jacob@caviumnetworks.com> <20161216044017.GA29607@santosh-Latitude-E5530-non-vPro> <20161222123614.GA8868@santosh-Latitude-E5530-non-vPro> From: Jianbo Liu Date: Fri, 23 Dec 2016 09:42:23 +0800 Message-ID: To: Santosh Shukla Cc: Jerin Jacob , dev@dpdk.org, "Ananyev, Konstantin" , Thomas Monjalon , Bruce Richardson , Jan Viktorin , Helin Zhang Content-Type: text/plain; charset=UTF-8 Subject: Re: [dpdk-dev] [PATCH 23/28] net/ixgbe: use eal I/O device memory read/write API X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 23 Dec 2016 01:42:24 -0000 Hi Santosh, On 22 December 2016 at 20:36, Santosh Shukla wrote: > Hi Jiangbo, > > On Thu, Dec 15, 2016 at 08:40:19PM -0800, Santosh Shukla wrote: >> On Thu, Dec 15, 2016 at 04:37:12PM +0800, Jianbo Liu wrote: >> > On 14 December 2016 at 09:55, Jerin Jacob >> > wrote: >> > > From: Santosh Shukla >> > > >> > >> > memory barrier operation is put inside IXGBE_PCI_REG_READ/WRITE in >> > your change, but I found rte_*mb is called before these macros in some >> > places. >> > Can you remove all these redundant calls? And please do the same >> > checking for other drivers. >> > >> >> Ok. >> >> Thinking of adding _relaxed_rd/wr style macro agnostic to arch for ixgbe case >> in particular. Such that for those code incident: >> x86 case> first default barrier + relaxed call. >> arm case> first default barrier + relaxed call. >> >> Does that make sense to you? If so then will take care in v2. >> >> Santosh. > > We spend time looking at drivers code where double barrier > may happen. Most of them are in driver init path, > configuration/control path code. So keeping double > barrier won't impact performance. > > We plan to replace only fast path code with _relaxed > style API's. That way we won't impact each driver > performance and we'll have the clean port. > > Does it make sense? Thought? > Yes, please continue your work.