From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-4.sys.kth.se (smtp-4.sys.kth.se [130.237.48.193]) by dpdk.org (Postfix) with ESMTP id 417F42C60 for ; Wed, 27 Mar 2019 17:08:09 +0100 (CET) Received: from smtp-4.sys.kth.se (localhost.localdomain [127.0.0.1]) by smtp-4.sys.kth.se (Postfix) with ESMTP id DC2762A9B; Wed, 27 Mar 2019 17:08:08 +0100 (CET) X-Virus-Scanned: by amavisd-new at kth.se Received: from smtp-4.sys.kth.se ([127.0.0.1]) by smtp-4.sys.kth.se (smtp-4.sys.kth.se [127.0.0.1]) (amavisd-new, port 10024) with LMTP id tpiAlwx1EQ90; Wed, 27 Mar 2019 17:08:08 +0100 (CET) X-KTH-Auth: barbette [130.237.20.142] DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kth.se; s=default; t=1553702888; bh=NVfmOgeqxWMt05FrDHMgCX35LbH3o/wvldgtVCJNqVc=; h=Subject:To:Cc:References:From:Date:In-Reply-To; b=eFv9cwb6F5MNX5QoOIh8f1yv97E/2nqd9aDczYVxOPp/+JmkE9r5GU74UZr+DyamE NUaLTrVbujz/gA6w/k54j5I0XahcTw29FXy5ZN5++Rb8jEnslzFO/F9ETke+mOGSGY XOxQtqqc2xnyfQXPhCVvJ+uNtuwxT2EYuonBXBH8= X-KTH-mail-from: barbette@kth.se Received: from [130.237.20.142] (s2587.it.kth.se [130.237.20.142]) by smtp-4.sys.kth.se (Postfix) with ESMTPSA id 48C87292B; Wed, 27 Mar 2019 17:08:04 +0100 (CET) To: "Wiles, Keith" , Stephen Hemminger Cc: dpdk-dev , "Richardson, Bruce" , "Mcnamara, John" , Thomas Monjalon , "Yigit, Ferruh" , Andrew Rybchenko , Shahaf Shuler , Yongseok Koh References: <20190327061935.19572-1-barbette@kth.se> <20190327074112.427c4758@shemminger-XPS-13-9360> <3652C395-2CA3-4F74-BD45-0F06386633FB@intel.com> From: Tom Barbette Message-ID: <650d6a84-0f8c-c750-afe3-500c91610a67@kth.se> Date: Wed, 27 Mar 2019 17:08:04 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.1 MIME-Version: 1.0 In-Reply-To: <3652C395-2CA3-4F74-BD45-0F06386633FB@intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] [PATCH v2 0/3] Add rte_eth_read_clock 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: Wed, 27 Mar 2019 16:08:09 -0000 On 2019-03-27 15:54, Wiles, Keith wrote: > I know the API rte_eht_read_clock() is attempting to read the NIC for this timestamp, but if the PMD does not support this request can we just default to the rte_rdtsc() as a return value? I would not advise that, because the goal of the function is to have something that is from the same unit than the hardware timestamp given in the mbufs. > The current timestamp API is a mess because not all devices behave the > same way. Trying to write an application that uses timestamping is > therefore > very difficult. This is different than timesync, no other devices implement hardware timestamping. For me, it's a different feature. Cheers, Tom From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by dpdk.space (Postfix) with ESMTP id E6FF5A05D3 for ; Wed, 27 Mar 2019 17:08:10 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 231064C94; Wed, 27 Mar 2019 17:08:10 +0100 (CET) Received: from smtp-4.sys.kth.se (smtp-4.sys.kth.se [130.237.48.193]) by dpdk.org (Postfix) with ESMTP id 417F42C60 for ; Wed, 27 Mar 2019 17:08:09 +0100 (CET) Received: from smtp-4.sys.kth.se (localhost.localdomain [127.0.0.1]) by smtp-4.sys.kth.se (Postfix) with ESMTP id DC2762A9B; Wed, 27 Mar 2019 17:08:08 +0100 (CET) X-Virus-Scanned: by amavisd-new at kth.se Received: from smtp-4.sys.kth.se ([127.0.0.1]) by smtp-4.sys.kth.se (smtp-4.sys.kth.se [127.0.0.1]) (amavisd-new, port 10024) with LMTP id tpiAlwx1EQ90; Wed, 27 Mar 2019 17:08:08 +0100 (CET) X-KTH-Auth: barbette [130.237.20.142] DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kth.se; s=default; t=1553702888; bh=NVfmOgeqxWMt05FrDHMgCX35LbH3o/wvldgtVCJNqVc=; h=Subject:To:Cc:References:From:Date:In-Reply-To; b=eFv9cwb6F5MNX5QoOIh8f1yv97E/2nqd9aDczYVxOPp/+JmkE9r5GU74UZr+DyamE NUaLTrVbujz/gA6w/k54j5I0XahcTw29FXy5ZN5++Rb8jEnslzFO/F9ETke+mOGSGY XOxQtqqc2xnyfQXPhCVvJ+uNtuwxT2EYuonBXBH8= X-KTH-mail-from: barbette@kth.se Received: from [130.237.20.142] (s2587.it.kth.se [130.237.20.142]) by smtp-4.sys.kth.se (Postfix) with ESMTPSA id 48C87292B; Wed, 27 Mar 2019 17:08:04 +0100 (CET) To: "Wiles, Keith" , Stephen Hemminger Cc: dpdk-dev , "Richardson, Bruce" , "Mcnamara, John" , Thomas Monjalon , "Yigit, Ferruh" , Andrew Rybchenko , Shahaf Shuler , Yongseok Koh References: <20190327061935.19572-1-barbette@kth.se> <20190327074112.427c4758@shemminger-XPS-13-9360> <3652C395-2CA3-4F74-BD45-0F06386633FB@intel.com> From: Tom Barbette Message-ID: <650d6a84-0f8c-c750-afe3-500c91610a67@kth.se> Date: Wed, 27 Mar 2019 17:08:04 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.1 MIME-Version: 1.0 In-Reply-To: <3652C395-2CA3-4F74-BD45-0F06386633FB@intel.com> Content-Type: text/plain; charset="UTF-8"; format="flowed" Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] [PATCH v2 0/3] Add rte_eth_read_clock 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: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Message-ID: <20190327160804.mzDuCjR99HGXlA4yN_awB7DNCD-wEVQ1OnQ7QGpSdjs@z> On 2019-03-27 15:54, Wiles, Keith wrote: > I know the API rte_eht_read_clock() is attempting to read the NIC for this timestamp, but if the PMD does not support this request can we just default to the rte_rdtsc() as a return value? I would not advise that, because the goal of the function is to have something that is from the same unit than the hardware timestamp given in the mbufs. > The current timestamp API is a mess because not all devices behave the > same way. Trying to write an application that uses timestamping is > therefore > very difficult. This is different than timesync, no other devices implement hardware timestamping. For me, it's a different feature. Cheers, Tom