From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 405F441E0B for ; Tue, 7 Mar 2023 23:14:07 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id DF187410DD; Tue, 7 Mar 2023 23:14:06 +0100 (CET) Received: from mail-pl1-f179.google.com (mail-pl1-f179.google.com [209.85.214.179]) by mails.dpdk.org (Postfix) with ESMTP id 3948C410DD for ; Tue, 7 Mar 2023 23:14:06 +0100 (CET) Received: by mail-pl1-f179.google.com with SMTP id a2so15734719plm.4 for ; Tue, 07 Mar 2023 14:14:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20210112.gappssmtp.com; s=20210112; t=1678227245; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=Wq0i/RWEjVrcB60O4N2Su5TOaUyriE92kFSIquZp5l8=; b=cO03OqvZqXrEHZdSZBPcPVbqN/t+clyZMRBAjYNSag6PzJWwA8dozTmGfw4OO7pcwz EbzvsEuIcBgkmMn5MQuDICWdJ0367FHSTq0VYUTfaaY512PjFaiVryMawKQdq8ua/nr9 XSru/XbFGzMe3ajNrC+10Wrk4tMLZ6cVAZ1CRqBiQdByOWsmV2TJDvAg85sIQP3wGy1z 4TGuIkf7Et6I8CYyBrE3Edvtp7vUYO1KWSPutLzV3P1c05DqCNEXqL2i3cxB1Ibu/vYm HfHKjydLYOMa5iNU66JGa5RrCYGHQigmYxC5d6KKUhC2gop/RasVHREXfxvFjxMs1n8a cCnw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1678227245; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Wq0i/RWEjVrcB60O4N2Su5TOaUyriE92kFSIquZp5l8=; b=tBQsbuAxq5rDEyOCElMKCptmulT9OEO0xgQARJ2D2Wg6g3rkO17CuV7bfDisvKV/pr rZhIYsqHZLzEtFi19skayd4mFHpMY3vIufM+ma08SnIgoTRi3ErsMpP4ztUFhVJ0MRo1 5T6YRrfWgiLZw0ij4eyk59bRI71XLYjKF0uB0IROJK6buKsFSC+oj2R8+cDhIG6qQh6I DsvmyQXcY5LJQaE+9PI82iCCqZpINi+GpdkaKBMf40RG5jOqcNlevxG5kZWhCCb3ClJm ECl9ApmjdL+moDM+nB+Ut+tP/BCWL6hQT6S4+DI4NJOElesipu+0z2YBbxNzAb/YpeZX i0iA== X-Gm-Message-State: AO0yUKXznnUwaBL7Xs3/TD5ZlZfnrHpBOcnM/bKMfTjQzHfQs2/Il3UE m+fMMTXvOYpd0Ktnj1Sb6ANgjA== X-Google-Smtp-Source: AK7set/2Ce7uquicBytBkbnPkh795bGfibVGGY8IrSjPsJwr0MjQbYoDKIToXcjL2xq52uip6SB2Pw== X-Received: by 2002:a17:903:1103:b0:19e:b2f3:e8c4 with SMTP id n3-20020a170903110300b0019eb2f3e8c4mr10536969plh.25.1678227245225; Tue, 07 Mar 2023 14:14:05 -0800 (PST) Received: from hermes.local (204-195-120-218.wavecable.com. [204.195.120.218]) by smtp.gmail.com with ESMTPSA id i18-20020a170902eb5200b001991e4e0bdcsm8828026pli.233.2023.03.07.14.14.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 07 Mar 2023 14:14:05 -0800 (PST) Date: Tue, 7 Mar 2023 14:14:03 -0800 From: Stephen Hemminger To: fwefew 4t4tg <7532yahoo@gmail.com> Cc: users@dpdk.org Subject: Re: Callback or hook into completion queues? Message-ID: <20230307141403.5657b8e9@hermes.local> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: users@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK usage discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: users-bounces@dpdk.org On Tue, 7 Mar 2023 17:07:41 -0500 fwefew 4t4tg <7532yahoo@gmail.com> wrote: > Once I call rte_eth_tx_burst() (Mellanox Connect5-LX) is there a way to > inspect or get a callback when transmitted packets go into the NIC's > completion queue? Not in DPDK. > > This is related to the earlier question on timestamping with rdtsc(). > Ideally I'd take the timestamp as soon (close) to the time the packet is on > the wire. > > I've looked at tx callbacks however this is invoked as the packet is about > to go into the "hardware queue for transmission" meaning there's lot's of > work + serialization of packet's data to electrical signals at NIC > bandwidth to come before the packet is on the wire. > > The ideal time to get run rdtsc() is when the NIC delivers a completion > event to a CQ for packets sent. > > Presumably there's something in the mlx5 driver or perhaps DMA library to > do this? Not that I have ever seen.