From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 6FB17A0093; Thu, 21 May 2020 21:57:15 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 5011D1D721; Thu, 21 May 2020 21:57:14 +0200 (CEST) Received: from mail-oo1-f41.google.com (mail-oo1-f41.google.com [209.85.161.41]) by dpdk.org (Postfix) with ESMTP id 9C3081D708 for ; Thu, 21 May 2020 21:57:12 +0200 (CEST) Received: by mail-oo1-f41.google.com with SMTP id p67so1686667ooa.11 for ; Thu, 21 May 2020 12:57:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=radio-canada-ca.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=z1V75voSFTqYk5CThil1ICOjZyjf0dH14lQq38uGJ+Q=; b=sC06/IYLKIcPGcF1rZ/0exGu1pV7wI6eMa/LaYzaKCW4fQNjAuBVT4XW7PXbGvNQ0K o8uILCPxSWlUG4dl4xg21OOzkAP3WKHyo6yfJC9TQRBWvUCfWDp6KhrO6vaTailq1tzD P4xr1eCqP0/IX/HdnEpyQOYM0UQyIN1T2S1+yEiiyOqDHMIrhNDlMzpimpKS4VYDpRCt yEvZhi28S6m/4hpXbZGqlzTTCOonYitdZyI/xncVOASVXuS2n2hFJo+SVGLafOaZeyq4 8WI2ZaOz3VjycT+e7nawgKh8Kaj8x5dZx7+vJ0uzz11VLw9d4N3mqcoYlbc/zW0Wsog+ OK5A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=z1V75voSFTqYk5CThil1ICOjZyjf0dH14lQq38uGJ+Q=; b=WNfhCAEM7ZjDiY1bL8L29KQ3th4o+Nm8rAebHlzQw6wEhS2wZw/yH84v3PQJra4Px9 Qj42BVboTKqaYGlyGQ69AikGVT9wuhjVGTQwB8NcgH6PZsLG88szCpdnFJlc7OqZebFD OrN2fgqQE/3f0y5qGjd+AWyKSH4lvi+H+SL3SE41q8Q7X7Ds/QlppFdxRh2EuCade88j pCg+8IzCo8bt//HHlIfbNfwW0WfRdDmPokV7qhbmvnHKszfLgAUQ4nyz0GlkxrZiiPw4 J/NpM8g4ApExzfL/A9XmRu5Q5LHI3BFAh8j1iy6OxSrroCWX6i6CajNwUoNLWhNavkYC 77Cw== X-Gm-Message-State: AOAM530EvaTWP5YHO9UFIbionP4Op4YfTzXPTC4vs3dYWFLxKi19+oFh 6m014FZYrHP+wZRQAEe1f4/VoivSC0afjk3ntiqt3w== X-Google-Smtp-Source: ABdhPJyQclXJeyj0Rj/M66BPpG/2BFsTc2Dn9iNB6jfjfynX8XQ1GaBAuD+eJPQB0aHeSwcDWnV+SaOo6Jpmi5t8TSo= X-Received: by 2002:a05:6820:229:: with SMTP id j9mr267229oob.32.1590091031744; Thu, 21 May 2020 12:57:11 -0700 (PDT) MIME-Version: 1.0 References: <3986292.sUUuQTochr@thomas> In-Reply-To: <3986292.sUUuQTochr@thomas> From: PATRICK KEROULAS Date: Thu, 21 May 2020 15:57:00 -0400 Message-ID: To: Thomas Monjalon , dev@dpdk.org Cc: Vivien Didelot Content-Type: text/plain; charset="UTF-8" Subject: Re: [dpdk-dev] mlx5 & pdump: convert HW timestamps to nanoseconds 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" > > I'm trying to build an accurate capture device based on Mellanox > > Connect-X5 with following requirements: > > - capture every incoming packets with hardware timestamps > > - output: pcap with timestamps in nanoseconds > > My problem is that the packets forwarded to `dpdk-pdump` carry raw > > timestamps from NIC clock. > > Please could you describe how you use dpdk-pdump? > Is it using the mlx5 PMD or pcap PMD? We're actually using both: # Rx, receive from NIC CONFIG_RTE_LIBRTE_MLX5_PMD=y # Tx, output to pcap file CONFIG_RTE_LIBRTE_PMD_PCAP=y $ sudo ./build/app/testpmd -w 0000:01:00.0 -w 0000:01:00.1 -n4 -- --enable-rx-timestamp $ dpdk-pdump -- --pdump 'port=0,queue=*,rx-dev=capture.pcap' We've sent this placeholder with the intention to start the discussion. https://github.com/DPDK/dpdk/commit/bd371e1ba5bfc5b7092d712a01bbc28799fd58bc.patch https://github.com/DPDK/dpdk/commit/e6f5c731c4ab27ab80b229af98c9b3d257e13843.patch > > mlx5 part of libibverbs includes a ts-to-ns converter which takes the > > instantaneous clock info. It's unused in dpdk so far. I've tested it in the > > device/port init routine and the result looks reliable. Since this approach > > looks very simple, compared to the time sync mechanism, I'm trying to > > integrate. > > > > The conversion should occur in the primary process (testpmd) I suppose. > > 1) The needed clock info derives from ethernet device. Is it possible to > > access that struct from a rx callback? > > 2) how to attach the nanosecond to mbuf so that `pdump` catches it? > > (workaround: copy `mbuf->udata64` in forwarded packets.) > > 3) any other idea? > > The timestamp is carried in mbuf. > Then the conversion must be done by the ethdev caller (application or > any other upper layer). What if the converter function needs a clock_info? https://github.com/linux-rdma/rdma-core/blob/7af01c79e00555207dee6132d72e7bfc1bb5485e/providers/mlx5/mlx5dv.h#L1201 I'm affraid this info may change by the time the converter is called by upper layer. Thanks, PK