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 902EAA0512; Wed, 3 Jun 2020 19:50:58 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id CC2D61D594; Wed, 3 Jun 2020 19:50:57 +0200 (CEST) Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by dpdk.org (Postfix) with ESMTP id 1B2661D585 for ; Wed, 3 Jun 2020 19:50:55 +0200 (CEST) IronPort-SDR: h9njPRlo37SJ3+PaoyDDqmFW4uoYeJlKT3fQuXbOs5n92fpnQdi6Zu6NnUZevvehZi2RFbGeRb cOp58aR0jJbQ== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Jun 2020 10:50:54 -0700 IronPort-SDR: 18NDfU8kftRlDZEjuWRdJhne3zKMwTPCVQIlIQ2wPbIx/aerCy+T54F0yEjaVhnC0/0zU4NYyL ndqThRX81s5g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,468,1583222400"; d="scan'208";a="304680643" Received: from fyigit-mobl.ger.corp.intel.com (HELO [10.213.199.102]) ([10.213.199.102]) by orsmga008.jf.intel.com with ESMTP; 03 Jun 2020 10:50:53 -0700 To: Vivien Didelot , dev@dpdk.org Cc: patrick.keroulas@radio-canada.ca, thomas@monjalon.net References: <20200523172130.2285380-1-vivien.didelot@gmail.com> From: Ferruh Yigit Autocrypt: addr=ferruh.yigit@intel.com; prefer-encrypt=mutual; keydata= mQINBFXZCFABEADCujshBOAaqPZpwShdkzkyGpJ15lmxiSr3jVMqOtQS/sB3FYLT0/d3+bvy qbL9YnlbPyRvZfnP3pXiKwkRoR1RJwEo2BOf6hxdzTmLRtGtwWzI9MwrUPj6n/ldiD58VAGQ +iR1I/z9UBUN/ZMksElA2D7Jgg7vZ78iKwNnd+vLBD6I61kVrZ45Vjo3r+pPOByUBXOUlxp9 GWEKKIrJ4eogqkVNSixN16VYK7xR+5OUkBYUO+sE6etSxCr7BahMPKxH+XPlZZjKrxciaWQb +dElz3Ab4Opl+ZT/bK2huX+W+NJBEBVzjTkhjSTjcyRdxvS1gwWRuXqAml/sh+KQjPV1PPHF YK5LcqLkle+OKTCa82OvUb7cr+ALxATIZXQkgmn+zFT8UzSS3aiBBohg3BtbTIWy51jNlYdy ezUZ4UxKSsFuUTPt+JjHQBvF7WKbmNGS3fCid5Iag4tWOfZoqiCNzxApkVugltxoc6rG2TyX CmI2rP0mQ0GOsGXA3+3c1MCdQFzdIn/5tLBZyKy4F54UFo35eOX8/g7OaE+xrgY/4bZjpxC1 1pd66AAtKb3aNXpHvIfkVV6NYloo52H+FUE5ZDPNCGD0/btFGPWmWRmkPybzColTy7fmPaGz cBcEEqHK4T0aY4UJmE7Ylvg255Kz7s6wGZe6IR3N0cKNv++O7QARAQABtCVGZXJydWggWWln aXQgPGZlcnJ1aC55aWdpdEBpbnRlbC5jb20+iQJsBBMBCgBWAhsDAh4BAheABQsJCAcDBRUK CQgLBRYCAwEABQkKqZZ8FiEE0jZTh0IuwoTjmYHH+TPrQ98TYR8FAl6ha3sXGHZrczovL2tl eXMub3BlbnBncC5vcmcACgkQ+TPrQ98TYR8uLA//QwltuFliUWe60xwmu9sY38c1DXvX67wk UryQ1WijVdIoj4H8cf/s2KtyIBjc89R254KMEfJDao/LrXqJ69KyGKXFhFPlF3VmFLsN4XiT PSfxkx8s6kHVaB3O183p4xAqnnl/ql8nJ5ph9HuwdL8CyO5/7dC/MjZ/mc4NGq5O9zk3YRGO lvdZAp5HW9VKW4iynvy7rl3tKyEqaAE62MbGyfJDH3C/nV/4+mPc8Av5rRH2hV+DBQourwuC ci6noiDP6GCNQqTh1FHYvXaN4GPMHD9DX6LtT8Fc5mL/V9i9kEVikPohlI0WJqhE+vQHFzR2 1q5nznE+pweYsBi3LXIMYpmha9oJh03dJOdKAEhkfBr6n8BWkWQMMiwfdzg20JX0o7a/iF8H 4dshBs+dXdIKzPfJhMjHxLDFNPNH8zRQkB02JceY9ESEah3wAbzTwz+e/9qQ5OyDTQjKkVOo cxC2U7CqeNt0JZi0tmuzIWrfxjAUulVhBmnceqyMOzGpSCQIkvalb6+eXsC9V1DZ4zsHZ2Mx Hi+7pCksdraXUhKdg5bOVCt8XFmx1MX4AoV3GWy6mZ4eMMvJN2hjXcrreQgG25BdCdcxKgqp e9cMbCtF+RZax8U6LkAWueJJ1QXrav1Jk5SnG8/5xANQoBQKGz+yFiWcgEs9Tpxth15o2v59 gXK5Ag0EV9ZMvgEQAKc0Db17xNqtSwEvmfp4tkddwW9XA0tWWKtY4KUdd/jijYqc3fDD54ES YpV8QWj0xK4YM0dLxnDU2IYxjEshSB1TqAatVWz9WtBYvzalsyTqMKP3w34FciuL7orXP4Ai bPtrHuIXWQOBECcVZTTOdZYGAzaYzxiAONzF9eTiwIqe9/oaOjTwTLnOarHt16QApTYQSnxD UQljeNvKYt1lZE/gAUUxNLWsYyTT+22/vU0GDUahsJxs1+f1yEr+OGrFiEAmqrzpF0lCS3f/ 3HVTU6rS9cK3glVUeaTF4+1SK5ZNO35piVQCwphmxa+dwTG/DvvHYCtgOZorTJ+OHfvCnSVj sM4kcXGjJPy3JZmUtyL9UxEbYlrffGPQI3gLXIGD5AN5XdAXFCjjaID/KR1c9RHd7Oaw0Pdc q9UtMLgM1vdX8RlDuMGPrj5sQrRVbgYHfVU/TQCk1C9KhzOwg4Ap2T3tE1umY/DqrXQgsgH7 1PXFucVjOyHMYXXugLT8YQ0gcBPHy9mZqw5mgOI5lCl6d4uCcUT0l/OEtPG/rA1lxz8ctdFB VOQOxCvwRG2QCgcJ/UTn5vlivul+cThi6ERPvjqjblLncQtRg8izj2qgmwQkvfj+h7Ex88bI 8iWtu5+I3K3LmNz/UxHBSWEmUnkg4fJlRr7oItHsZ0ia6wWQ8lQnABEBAAGJAjwEGAEKACYC GwwWIQTSNlOHQi7ChOOZgcf5M+tD3xNhHwUCXqFrngUJCKxSYAAKCRD5M+tD3xNhH3YWD/9b cUiWaHJasX+OpiuZ1Li5GG3m9aw4lR/k2lET0UPRer2Jy1JsL+uqzdkxGvPqzFTBXgx/6Byz EMa2mt6R9BCyR286s3lxVS5Bgr5JGB3EkpPcoJT3A7QOYMV95jBiiJTy78Qdzi5LrIu4tW6H o0MWUjpjdbR01cnj6EagKrDx9kAsqQTfvz4ff5JIFyKSKEHQMaz1YGHyCWhsTwqONhs0G7V2 0taQS1bGiaWND0dIBJ/u0pU998XZhmMzn765H+/MqXsyDXwoHv1rcaX/kcZIcN3sLUVcbdxA WHXOktGTQemQfEpCNuf2jeeJlp8sHmAQmV3dLS1R49h0q7hH4qOPEIvXjQebJGs5W7s2vxbA 5u5nLujmMkkfg1XHsds0u7Zdp2n200VC4GQf8vsUp6CSMgjedHeF9zKv1W4lYXpHp576ZV7T GgsEsvveAE1xvHnpV9d7ZehPuZfYlP4qgo2iutA1c0AXZLn5LPcDBgZ+KQZTzm05RU1gkx7n gL9CdTzVrYFy7Y5R+TrE9HFUnsaXaGsJwOB/emByGPQEKrupz8CZFi9pkqPuAPwjN6Wonokv ChAewHXPUadcJmCTj78Oeg9uXR6yjpxyFjx3vdijQIYgi5TEGpeTQBymLANOYxYWYOjXk+ae dYuOYKR9nbPv+2zK9pwwQ2NXbUBystaGyQ== Message-ID: <1d7b6c2e-84a9-5e20-1353-4f64de667b03@intel.com> Date: Wed, 3 Jun 2020 18:50:51 +0100 MIME-Version: 1.0 In-Reply-To: <20200523172130.2285380-1-vivien.didelot@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] [PATCH 1/2] net/pcap: support software Tx nanosecond timestamp 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" On 5/23/2020 6:21 PM, Vivien Didelot wrote: > When capturing packets into a PCAP file, DPDK currently uses > microseconds for the timestamp. But libpcap supports interpreting > tv_usec as nanoseconds depending on the file timestamp precision. > > To support this, use PCAP_TSTAMP_PRECISION_NANO when creating the > empty PCAP file as specified by PCAP_OPEN_DEAD(3PCAP) and implement > nanosecond timeval addition. This also ensures that the precision > reported by capinfos is nanoseconds (9). Overall good idea and patch looks good. Only concern is change in the libpcap dependency. Do you know which libpcap version supports 'PCAP_TSTAMP_PRECISION_NANO'? If a user of pcap PMD updates to latest DPDK and the environment doesn't have new version of the libpcap, this change will require an environment update and this may or may not be easy to do. That is why not sure if the updates require dependency change should wait for the LTS or not. Another things is the backward compatibility, as far as I understand the pcap file recorded with nanosecond precision can be read and parsed without problem by old application that doesn't know the nanosecond precision, but can you please confirm this? Thanks, ferruh > > Signed-off-by: Vivien Didelot > --- > drivers/net/pcap/rte_eth_pcap.c | 15 ++++++++++++--- > 1 file changed, 12 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/pcap/rte_eth_pcap.c b/drivers/net/pcap/rte_eth_pcap.c > index b4c79d174..68588c3d7 100644 > --- a/drivers/net/pcap/rte_eth_pcap.c > +++ b/drivers/net/pcap/rte_eth_pcap.c > @@ -287,6 +287,8 @@ eth_null_rx(void *queue __rte_unused, > return 0; > } > > +#define NSEC_PER_SEC 1e9 > + > static inline void > calculate_timestamp(struct timeval *ts) { > uint64_t cycles; > @@ -294,8 +296,14 @@ calculate_timestamp(struct timeval *ts) { > > cycles = rte_get_timer_cycles() - start_cycles; > cur_time.tv_sec = cycles / hz; > - cur_time.tv_usec = (cycles % hz) * 1e6 / hz; > - timeradd(&start_time, &cur_time, ts); > + cur_time.tv_usec = (cycles % hz) * NSEC_PER_SEC / hz; > + > + ts->tv_sec = start_time.tv_sec + cur_time.tv_sec; > + ts->tv_usec = start_time.tv_usec + cur_time.tv_usec; > + if (ts->tv_usec > NSEC_PER_SEC) { > + ts->tv_usec -= NSEC_PER_SEC; > + ts->tv_sec += 1; > + } > } > > /* > @@ -475,7 +483,8 @@ open_single_tx_pcap(const char *pcap_filename, pcap_dumper_t **dumper) > * with pcap_dump_open(). We create big enough an Ethernet > * pcap holder. > */ > - tx_pcap = pcap_open_dead(DLT_EN10MB, RTE_ETH_PCAP_SNAPSHOT_LEN); > + tx_pcap = pcap_open_dead_with_tstamp_precision(DLT_EN10MB, > + RTE_ETH_PCAP_SNAPSHOT_LEN, PCAP_TSTAMP_PRECISION_NANO); > if (tx_pcap == NULL) { > PMD_LOG(ERR, "Couldn't create dead pcap"); > return -1; >