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 D0E89A04DF; Fri, 30 Oct 2020 10:27:16 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 2F5F19B04; Fri, 30 Oct 2020 10:27:14 +0100 (CET) Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id 58C739AFD for ; Fri, 30 Oct 2020 10:27:11 +0100 (CET) IronPort-SDR: MLQiH08pAJViRc0ZI6UL/liWO3bODbizn9g3uD24GoUbEFMzXBLWL5I7GJ9LIzAHKSkTyTHn3p MWwqPX9Uy5lQ== X-IronPort-AV: E=McAfee;i="6000,8403,9789"; a="165086153" X-IronPort-AV: E=Sophos;i="5.77,432,1596524400"; d="scan'208";a="165086153" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Oct 2020 02:27:10 -0700 IronPort-SDR: u6pBPKaF8ZmWbKyuqTgF/0lf+qK3I/YjHk4FYMuGwmPJTDhNn1GZFnTFfgDZpl3giWBzchMCx2 jkFJJp+hfhhg== X-IronPort-AV: E=Sophos;i="5.77,432,1596524400"; d="scan'208";a="537006159" Received: from fyigit-mobl1.ger.corp.intel.com (HELO [10.252.23.197]) ([10.252.23.197]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Oct 2020 02:27:08 -0700 To: Bruce Richardson , =?UTF-8?Q?Morten_Br=c3=b8rup?= Cc: thomas@monjalon.net, arybchenko@solarflare.com, jia.guo@intel.com, dev@dpdk.org References: <20200914110511.95609-1-mb@smartsharesystems.com> <20201027102415.GB936@bricha3-MOBL.ger.corp.intel.com> From: Ferruh Yigit Message-ID: <5c70bcf3-f596-f2e2-beca-160aa7237f11@intel.com> Date: Fri, 30 Oct 2020 09:27:04 +0000 MIME-Version: 1.0 In-Reply-To: <20201027102415.GB936@bricha3-MOBL.ger.corp.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] [PATCH] ethdev: rte_eth_rx_burst() nb_pkts requirements 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 10/27/2020 10:24 AM, Bruce Richardson wrote: > On Mon, Sep 14, 2020 at 01:05:11PM +0200, Morten Brørup wrote: >> Updated description of rte_eth_rx_burst() to reflect what drivers, >> when using vector instructions, expect from nb_pkts. >> >> Also discussed on the mailing list here: >> http://inbox.dpdk.org/dev/98CBD80474FA8B44BF855DF32C47DC35C61257@smartserver.smartshare.dk/ >> >> Signed-off-by: Morten Brørup >> --- >> lib/librte_ethdev/rte_ethdev.h | 5 +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git a/lib/librte_ethdev/rte_ethdev.h b/lib/librte_ethdev/rte_ethdev.h >> index 70295d7ab..41f8ba4ef 100644 >> --- a/lib/librte_ethdev/rte_ethdev.h >> +++ b/lib/librte_ethdev/rte_ethdev.h >> @@ -4469,6 +4469,10 @@ int rte_eth_dev_hairpin_capability_get(uint16_t port_id, >> * burst-oriented optimizations in both synchronous and asynchronous >> * packet processing environments with no overhead in both cases. >> * >> + * @note >> + * Some drivers using vector instructions require that *nb_pkts* is >> + * divisible by 4 or 8, depending on the driver implementation. >> + * >> * The rte_eth_rx_burst() function does not provide any error >> * notification to avoid the corresponding overhead. As a hint, the >> * upper-level application might check the status of the device link once >> @@ -4485,6 +4489,7 @@ int rte_eth_dev_hairpin_capability_get(uint16_t port_id, >> * must be large enough to store *nb_pkts* pointers in it. >> * @param nb_pkts >> * The maximum number of packets to retrieve. >> + * The value must be divisible by 8 in order to work with any driver. >> * @return >> * The number of packets actually retrieved, which is the number >> * of pointers to *rte_mbuf* structures effectively supplied to the >> -- > > This correctly documents the current situation, so following the discussion > on-list: > > Acked-by: Bruce Richardson > Applied to dpdk-next-net/main, thanks.