From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f48.google.com (mail-wm0-f48.google.com [74.125.82.48]) by dpdk.org (Postfix) with ESMTP id 50F7858CF for ; Tue, 21 Feb 2017 10:53:57 +0100 (CET) Received: by mail-wm0-f48.google.com with SMTP id v77so70960153wmv.0 for ; Tue, 21 Feb 2017 01:53:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=6wind-com.20150623.gappssmtp.com; s=20150623; h=from:date:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=2nfv29qJ0haz1oH3nOeaTJqlm0OTZj44aOYEVGSMe0E=; b=PuFmjw0rEiMzfZboDj+MkeSf/6kwgd2Ml+uQcBjsu73inrtHbL+CbiFNR1yXeYQZb9 uylqz0DmwqKcw3iCsMFnHYqvxX4oHUCvdGb6Q5ZW27Nq5wYOI5lzqDANbJkFeUtBG0uA nnGO2qObMepRUEzzY2NSjagklHmZ+YcBsxBtNFrZKggdbdhE1j2EBGDNqgD1MmKBB/be eaLrA66Pf0vEC6tJg8h/zQd6xwQFh7VR04ox6byOUDYfZ26ic7rfIrsGQYh00ZeBtm1D xYpU0C0rs+sKaWu8v/39VmI7QVVmplhcVEbh7uYO80YlmdRmgwZ8Wmj5cfIQ5fFk1FEM ypHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=2nfv29qJ0haz1oH3nOeaTJqlm0OTZj44aOYEVGSMe0E=; b=ZgahEyrClrFMyTZoJCpG7xMqgSgLaQv0DDdD2l/FjlFvqUFmPKaDryDh5kfST+S4M1 1UBrScVoqXOyU5nYBvHlfsqgYoDlsI6ys4eezytiel2oow3sI+XgQ8+nNhTTzNA+pLEm b7nn7uEJ+qHFs06ZwPdQk/k+xhrQ89fZQv37DkJZW6CLYBiWtrkq/LT2pI/XtYiPsxiE yIpIpZuLyUMWNxobmpPG0onXRL8JJaa6UoDZjXWWD6HFXWHxuochT8xfkrnJ0QAmUDib tqpqw1h6bubO/LxqNo3vbGQtALhH0m3bNwgJ8+u91Ju+qRnY7buuJjQZVbT1++Nc5DdJ fWPg== X-Gm-Message-State: AMke39kXRrUhP8NdPk6dbAKrdQ/AqGU0WBn5qHLS5qBrt4RgGhsm3E16sjtB51ppef1womrY X-Received: by 10.28.198.65 with SMTP id w62mr14103084wmf.123.1487670837100; Tue, 21 Feb 2017 01:53:57 -0800 (PST) Received: from glumotte.dev.6wind.com (host.78.145.23.62.rev.coltfrance.com. [62.23.145.78]) by smtp.gmail.com with ESMTPSA id w207sm16860002wmw.29.2017.02.21.01.53.56 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 21 Feb 2017 01:53:56 -0800 (PST) From: Olivier MATZ X-Google-Original-From: Olivier MATZ Date: Tue, 21 Feb 2017 10:53:49 +0100 To: "Ananyev, Konstantin" Cc: Olivier Matz , Jan Blunck , "dev@dpdk.org" Message-ID: <20170221105349.1fb36287@glumotte.dev.6wind.com> In-Reply-To: <2601191342CEEE43887BDE71AB9772583F118DD7@irsmsx105.ger.corp.intel.com> References: <1485271173-13408-1-git-send-email-olivier.matz@6wind.com> <2601191342CEEE43887BDE71AB9772583F111A29@irsmsx105.ger.corp.intel.com> <20170216144807.7add2c71@platinum> <20170217115153.0afeb061@platinum> <20170217151708.20bf4a49@platinum> <2601191342CEEE43887BDE71AB9772583F118DD7@irsmsx105.ger.corp.intel.com> X-Mailer: Claws Mail 3.14.1 (GTK+ 2.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] [RFC 0/8] mbuf: structure reorganization 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: Tue, 21 Feb 2017 09:53:57 -0000 Hi Konstantin, On Fri, 17 Feb 2017 18:42:01 +0000, "Ananyev, Konstantin" wrote: > Hi guys, > > > > My point is that I still doubt that it belongs into the first > > > cacheline. It requires accessing other structures for converting > > > into nanoseconds anyway. Optimally I would like to see this > > > happening on access instead but if that isn't achievable at least > > > in a second step. > > > > Sorry, I don't really get your point. My comprehension of the > > timestamp usage in a PMD is as following: > > > > rx_burst(struct rxq *rxq, ...) > > { > > unsigned long factor = rxq->timestamp_factor; > > unsigned port = rxq->port; > > > > for each hw_desc { > > m = rte_pktmbuf_alloc(rxq->pool); > > m->len = hw_desc->len; > > m->port = port; > > m->ol_flags = > > ... > > m->timestamp = hw_desc->timestamp * factor; > > } > > ... > > } > > > > In that case, I think it deserves to be in the 1st cache line. > > So you are saying that: > - for some HW that DPDK supports (mlx?) timestamp information > Is available in HW RX descriptor > - and as soon timestamp field will be available in mbuf, you plan > to populate it using this HW RXD field. > Is that so? Yes, that's what I'm seeing in mellanox's patchset: http://dpdk.org/ml/archives/dev/2016-October/048810.html Do you know if Intel has plans to support some sort of timestamp using this timestamp field? Thanks, Olivier