From patchwork Wed Feb 5 02:41:11 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Song, Yoong Siang" X-Patchwork-Id: 13960449 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6F964200A3; Wed, 5 Feb 2025 02:41:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.17 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738723290; cv=none; b=T35gZkVy0t7AXkfuhb+8SMaYxP18SFa4sBy6mrWR+RA6zcNhpmaUMzOOmHY7oi0Dj5Zq/WorGorf+rHqNJ3ZiFm9uVZeO/Hp+GrGJxS/VMM+qEsJuERlz2+bNK5fMM1x8pOkl7iIYOC37u9D7pTovrk0FA3TmL1OOfcLTpKR/es= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738723290; c=relaxed/simple; bh=JZgQkH+UIDzCx9TfxkKdm4ixBg9gHdAsFun4ac3uwuI=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=EbSknLqmJ/0GVu0jp43PLRuqlXi9h+dgkhwUzYjrzf86h2XgomJhmiPRqjtYR5S7S207YE68iES4GS0miiKKsD3mZgGs8aY6bbvjB0jf650OHHwkWQI0uiJMavtnjQLyxs/zD8JMr+nzzeqEiuRLELwNVXmNet38BuNvuJDvseY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=MtRL4UOW; arc=none smtp.client-ip=198.175.65.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="MtRL4UOW" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1738723289; x=1770259289; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=JZgQkH+UIDzCx9TfxkKdm4ixBg9gHdAsFun4ac3uwuI=; b=MtRL4UOWGHZMZ6yFBnvWDoVXcNd6NqW5zsOhgHxu9LyMJ5nICXXsieP8 bF1RorcokpvLszObH+aNd9bgG126Afo6yKrWekp0/tCB99akcWiyMt1+c GeDSxSRCF0BUveucvqR8IdZr4zCNuAB+fwBjsFf/cNxkss0dJAyTUcchr Y6ThvikG8tAPV5GQh4SXxJp67Bk0DEUsgKUFyR/NaLL3F4A9Ji0Rc0Iya ON4awoFKrSUMv7b7Gj3W8DTo2LBHl7se9mwFUsC6ty9EqyKFDjUpeVdhR scCkqCwb43+NTH0s2m4hgWOCD5qa7mSl9gjD2Pdap8LiIZBbWF+RLBxH/ Q==; X-CSE-ConnectionGUID: FFbxe7pUSsqgE6ZjdQpOgg== X-CSE-MsgGUID: /2I1bgl6RqSJDAcCc20ruA== X-IronPort-AV: E=McAfee;i="6700,10204,11336"; a="39303770" X-IronPort-AV: E=Sophos;i="6.13,260,1732608000"; d="scan'208";a="39303770" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa109.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Feb 2025 18:41:28 -0800 X-CSE-ConnectionGUID: Z7J4DcRpRnOCPPqiQ72SdA== X-CSE-MsgGUID: IyDqqxbBR3i9rCAWSoy8yA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.13,260,1732608000"; d="scan'208";a="110666534" Received: from p12ill20yoongsia.png.intel.com ([10.88.227.38]) by fmviesa007.fm.intel.com with ESMTP; 04 Feb 2025 18:41:16 -0800 From: Song Yoong Siang To: "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Willem de Bruijn , Florian Bezdeka , Donald Hunter , Jonathan Corbet , Bjorn Topel , Magnus Karlsson , Maciej Fijalkowski , Jonathan Lemon , Andrew Lunn , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Joe Damato , Stanislav Fomichev , Xuan Zhuo , Mina Almasry , Daniel Jurgens , Song Yoong Siang , Andrii Nakryiko , Eduard Zingerman , Mykola Lysenko , Martin KaFai Lau , Song Liu , Yonghong Song , KP Singh , Hao Luo , Jiri Olsa , Shuah Khan , Alexandre Torgue , Jose Abreu , Maxime Coquelin , Tony Nguyen , Przemek Kitszel , Faizal Rahim , Choong Yong Liang , Bouska Zdenek Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, intel-wired-lan@lists.osuosl.org, xdp-hints@xdp-project.net Subject: [PATCH bpf-next v8 0/5] xsk: TX metadata Launch Time support Date: Wed, 5 Feb 2025 10:41:11 +0800 Message-Id: <20250205024116.798862-1-yoong.siang.song@intel.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 This series expands the XDP TX metadata framework to allow user applications to pass per packet 64-bit launch time directly to the kernel driver, requesting launch time hardware offload support. The XDP TX metadata framework will not perform any clock conversion or packet reordering. Please note that the role of Tx metadata is just to pass the launch time, not to enable the offload feature. Users will need to enable the launch time hardware offload feature of the device by using the respective command, such as the tc-etf command. Although some devices use the tc-etf command to enable their launch time hardware offload feature, xsk packets will not go through the etf qdisc. Therefore, in my opinion, the launch time should always be based on the PTP Hardware Clock (PHC). Thus, i did not include a clock ID to indicate the clock source. To simplify the test steps, I modified the xdp_hw_metadata bpf self-test tool in such a way that it will set the launch time based on the offset provided by the user and the value of the Receive Hardware Timestamp, which is against the PHC. This will eliminate the need to discipline System Clock with the PHC and then use clock_gettime() to get the time. Please note that AF_XDP lacks a feedback mechanism to inform the application if the requested launch time is invalid. So, users are expected to familiar with the horizon of the launch time of the device they use and not request a launch time that is beyond the horizon. Otherwise, the driver might interpret the launch time incorrectly and react wrongly. For stmmac and igc, where modulo computation is used, a launch time larger than the horizon will cause the device to transmit the packet earlier that the requested launch time. Although there is no feedback mechanism for the launch time request for now, user still can check whether the requested launch time is working or not, by requesting the Transmit Completion Hardware Timestamp. V8: - check the number of used descriptor in xsk_tx_metadata_request() by using used_desc of struct igc_metadata_request, and then decreases the budget with it (Maciej) V7: https://lore.kernel.org/netdev/20250204004907.789330-1-yoong.siang.song@intel.com/ - split the refactoring code of igc empty packet insertion into a separate commit (Faizal) - add explanation on why the value "4" is used as igc transmit budget (Faizal) - perform a stress test by sending 1000 packets with 10ms interval and launch time set to 500us in the future (Faizal & Yong Liang) V6: https://lore.kernel.org/netdev/20250116155350.555374-1-yoong.siang.song@intel.com/ - fix selftest build errors by using asprintf() and realloc(), instead of managing the buffer sizes manually (Daniel, Stanislav) V5: https://lore.kernel.org/netdev/20250114152718.120588-1-yoong.siang.song@intel.com/ - change netdev feature name from tx-launch-time to tx-launch-time-fifo to explicitly state the FIFO behaviour (Stanislav) - improve the looping of xdp_hw_metadata app to wait for packet tx completion to be more readable by using clock_gettime() (Stanislav) - add launch time setup steps into xdp_hw_metadata app (Stanislav) V4: https://lore.kernel.org/netdev/20250106135506.9687-1-yoong.siang.song@intel.com/ - added XDP launch time support to the igc driver (Jesper & Florian) - added per-driver launch time limitation on xsk-tx-metadata.rst (Jesper) - added explanation on FIFO behavior on xsk-tx-metadata.rst (Jakub) - added step to enable launch time in the commit message (Jesper & Willem) - explicitly documented the type of launch_time and which clock source it is against (Willem) V3: https://lore.kernel.org/netdev/20231203165129.1740512-1-yoong.siang.song@intel.com/ - renamed to use launch time (Jesper & Willem) - changed the default launch time in xdp_hw_metadata apps from 1s to 0.1s because some NICs do not support such a large future time. V2: https://lore.kernel.org/netdev/20231201062421.1074768-1-yoong.siang.song@intel.com/ - renamed to use Earliest TxTime First (Willem) - renamed to use txtime (Willem) V1: https://lore.kernel.org/netdev/20231130162028.852006-1-yoong.siang.song@intel.com/ Song Yoong Siang (5): xsk: Add launch time hardware offload support to XDP Tx metadata selftests/bpf: Add launch time request to xdp_hw_metadata net: stmmac: Add launch time support to XDP ZC igc: Refactor empty packet insertion into a reusable function igc: Add launch time support to XDP ZC Documentation/netlink/specs/netdev.yaml | 4 + Documentation/networking/xsk-tx-metadata.rst | 62 +++++++ drivers/net/ethernet/intel/igc/igc.h | 1 + drivers/net/ethernet/intel/igc/igc_main.c | 94 +++++++--- drivers/net/ethernet/stmicro/stmmac/stmmac.h | 2 + .../net/ethernet/stmicro/stmmac/stmmac_main.c | 13 ++ include/net/xdp_sock.h | 10 ++ include/net/xdp_sock_drv.h | 1 + include/uapi/linux/if_xdp.h | 10 ++ include/uapi/linux/netdev.h | 3 + net/core/netdev-genl.c | 2 + net/xdp/xsk.c | 3 + tools/include/uapi/linux/if_xdp.h | 10 ++ tools/include/uapi/linux/netdev.h | 3 + tools/testing/selftests/bpf/xdp_hw_metadata.c | 168 +++++++++++++++++- 15 files changed, 359 insertions(+), 27 deletions(-)