From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.17]) by mail.toke.dk (Postfix) with ESMTPS id 21588AF7380 for ; Wed, 05 Feb 2025 03:42:23 +0100 (CET) Authentication-Results: mail.toke.dk; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=OPW5Sqka DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1738723344; x=1770259344; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=ksaAaaoLVoDgCUczAlEVx+8YvcmGLf/2DZVsnOi+dMg=; b=OPW5Sqka0f3kClJrpt9T881jSPPpq2wOpy/iSp33kg1IW0c2iBHhIuCA 7bU0HaBYoDWiOuXX35J/iEVN01MBvzL4k+y9kk6RIlxxtk9YBdteTUYp6 0LZ2MQ05hYw5CqlqvqILkSz6j7qvNYRqk5K6V3SmcQyH5tYC8w62otJ8t CAdZCdjXyrHP8ZBk04WV89iTiLXXH+hSpu52c/PIEsX4jw6WAWvtxZb+H ivEv4v0uEww7M/wdheeTF8v8m2fnJc7uws/oaNMDWbK4QpLgBBkp45B40 cnzIBWXzCK80YVdmYkrlk0Cgr4RaxqFlMt/ksc7ujjE+TDsNB6ahyuED+ Q==; X-CSE-ConnectionGUID: GsqP5R0QTT6dQTMiyWpW1Q== X-CSE-MsgGUID: jQKeDw6vRvy7V3QorQJV4w== X-IronPort-AV: E=McAfee;i="6700,10204,11336"; a="39303941" X-IronPort-AV: E=Sophos;i="6.13,260,1732608000"; d="scan'208";a="39303941" 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 18:42:22 -0800 X-CSE-ConnectionGUID: 2d39cPQ/SOaBgbXAfBQn9g== X-CSE-MsgGUID: /2zzmDmhTZ+9sGS70cNnQA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.13,260,1732608000"; d="scan'208";a="110666614" Received: from p12ill20yoongsia.png.intel.com ([10.88.227.38]) by fmviesa007.fm.intel.com with ESMTP; 04 Feb 2025 18:42:11 -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 Date: Wed, 5 Feb 2025 10:41:16 +0800 Message-Id: <20250205024116.798862-6-yoong.siang.song@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250205024116.798862-1-yoong.siang.song@intel.com> References: <20250205024116.798862-1-yoong.siang.song@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: 7AIC32N7FOVV5U5AIEYEY544BMTKLEAQ X-Message-ID-Hash: 7AIC32N7FOVV5U5AIEYEY544BMTKLEAQ X-MailFrom: yoong.siang.song@intel.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; loop; banned-address; emergency; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header 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 X-Mailman-Version: 3.3.10 Precedence: list Subject: [xdp-hints] [PATCH bpf-next v8 5/5] igc: Add launch time support to XDP ZC List-Id: XDP hardware hints design discussion Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: Enable Launch Time Control (LTC) support for XDP zero copy via XDP Tx metadata framework. This patch has been tested with tools/testing/selftests/bpf/xdp_hw_metadata on Intel I225-LM Ethernet controller. Below are the test steps and result. Test 1: Send a single packet with the launch time set to 1 s in the future. Test steps: 1. On the DUT, start the xdp_hw_metadata selftest application: $ sudo ./xdp_hw_metadata enp2s0 -l 1000000000 -L 1 2. On the Link Partner, send a UDP packet with VLAN priority 1 to port 9091 of the DUT. Result: When the launch time is set to 1 s in the future, the delta between the launch time and the transmit hardware timestamp is 0.016 us, as shown in printout of the xdp_hw_metadata application below. 0x562ff5dc8880: rx_desc[4]->addr=84110 addr=84110 comp_addr=84110 EoP rx_hash: 0xE343384 with RSS type:0x1 HW RX-time: 1734578015467548904 (sec:1734578015.4675) delta to User RX-time sec:0.0002 (183.103 usec) XDP RX-time: 1734578015467651698 (sec:1734578015.4677) delta to User RX-time sec:0.0001 (80.309 usec) No rx_vlan_tci or rx_vlan_proto, err=-95 0x562ff5dc8880: ping-pong with csum=561c (want c7dd) csum_start=34 csum_offset=6 HW RX-time: 1734578015467548904 (sec:1734578015.4675) delta to HW Launch-time sec:1.0000 (1000000.000 usec) 0x562ff5dc8880: complete tx idx=4 addr=4018 HW Launch-time: 1734578016467548904 (sec:1734578016.4675) delta to HW TX-complete-time sec:0.0000 (0.016 usec) HW TX-complete-time: 1734578016467548920 (sec:1734578016.4675) delta to User TX-complete-time sec:0.0000 (32.546 usec) XDP RX-time: 1734578015467651698 (sec:1734578015.4677) delta to User TX-complete-time sec:0.9999 (999929.768 usec) HW RX-time: 1734578015467548904 (sec:1734578015.4675) delta to HW TX-complete-time sec:1.0000 (1000000.016 usec) 0x562ff5dc8880: complete rx idx=132 addr=84110 Test 2: Send 1000 packets with a 10 ms interval and the launch time set to 500 us in the future. Test steps: 1. On the DUT, start the xdp_hw_metadata selftest application: $ sudo chrt -f 99 ./xdp_hw_metadata enp2s0 -l 500000 -L 1 > \ /dev/shm/result.log 2. On the Link Partner, send 1000 UDP packets with a 10 ms interval and VLAN priority 1 to port 9091 of the DUT. Result: When the launch time is set to 500 us in the future, the average delta between the launch time and the transmit hardware timestamp is 0.016 us, as shown in the analysis of /dev/shm/result.log below. The XDP launch time works correctly in sending 1000 packets continuously. Min delta: 0.005 us Avr delta: 0.016 us Max delta: 0.031 us Total packets forwarded: 1000 Signed-off-by: Song Yoong Siang --- drivers/net/ethernet/intel/igc/igc.h | 1 + drivers/net/ethernet/intel/igc/igc_main.c | 52 ++++++++++++++++++++++- 2 files changed, 51 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/intel/igc/igc.h index b8111ad9a9a8..cd1d7b6c1782 100644 --- a/drivers/net/ethernet/intel/igc/igc.h +++ b/drivers/net/ethernet/intel/igc/igc.h @@ -579,6 +579,7 @@ struct igc_metadata_request { struct xsk_tx_metadata *meta; struct igc_ring *tx_ring; u32 cmd_type; + u16 used_desc; }; struct igc_q_vector { diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c index 553d6d82af0d..a4ec487da701 100644 --- a/drivers/net/ethernet/intel/igc/igc_main.c +++ b/drivers/net/ethernet/intel/igc/igc_main.c @@ -2954,9 +2954,39 @@ static u64 igc_xsk_fill_timestamp(void *_priv) return *(u64 *)_priv; } +static void igc_xsk_request_launch_time(u64 launch_time, void *_priv) +{ + struct igc_metadata_request *meta_req = _priv; + struct igc_ring *tx_ring = meta_req->tx_ring; + __le32 launch_time_offset; + bool insert_empty = false; + bool first_flag = false; + + if (!tx_ring->launchtime_enable) + return; + + launch_time_offset = igc_tx_launchtime(tx_ring, + ns_to_ktime(launch_time), + &first_flag, &insert_empty); + if (insert_empty) { + igc_insert_empty_packet(tx_ring); + meta_req->tx_buffer = + &tx_ring->tx_buffer_info[tx_ring->next_to_use]; + /* Inserting an empty packet requires two descriptors: + * one data descriptor and one context descriptor. + */ + meta_req->used_desc += 2; + } + + /* Use one context descriptor to specify launch time and first flag. */ + igc_tx_ctxtdesc(tx_ring, launch_time_offset, first_flag, 0, 0, 0); + meta_req->used_desc += 1; +} + const struct xsk_tx_metadata_ops igc_xsk_tx_metadata_ops = { .tmo_request_timestamp = igc_xsk_request_timestamp, .tmo_fill_timestamp = igc_xsk_fill_timestamp, + .tmo_request_launch_time = igc_xsk_request_launch_time, }; static void igc_xdp_xmit_zc(struct igc_ring *ring) @@ -2979,7 +3009,13 @@ static void igc_xdp_xmit_zc(struct igc_ring *ring) ntu = ring->next_to_use; budget = igc_desc_unused(ring); - while (xsk_tx_peek_desc(pool, &xdp_desc) && budget--) { + /* Packets with launch time require one data descriptor and one context + * descriptor. When the launch time falls into the next Qbv cycle, we + * may need to insert an empty packet, which requires two more + * descriptors. Therefore, to be safe, we always ensure we have at least + * 4 descriptors available. + */ + while (xsk_tx_peek_desc(pool, &xdp_desc) && budget >= 4) { struct igc_metadata_request meta_req; struct xsk_tx_metadata *meta = NULL; struct igc_tx_buffer *bi; @@ -3000,9 +3036,19 @@ static void igc_xdp_xmit_zc(struct igc_ring *ring) meta_req.tx_ring = ring; meta_req.tx_buffer = bi; meta_req.meta = meta; + meta_req.used_desc = 0; xsk_tx_metadata_request(meta, &igc_xsk_tx_metadata_ops, &meta_req); + /* xsk_tx_metadata_request() may have updated next_to_use */ + ntu = ring->next_to_use; + + /* xsk_tx_metadata_request() may have updated Tx buffer info */ + bi = meta_req.tx_buffer; + + /* xsk_tx_metadata_request() may use a few descriptors */ + budget -= meta_req.used_desc; + tx_desc = IGC_TX_DESC(ring, ntu); tx_desc->read.cmd_type_len = cpu_to_le32(meta_req.cmd_type); tx_desc->read.olinfo_status = cpu_to_le32(olinfo_status); @@ -3020,9 +3066,11 @@ static void igc_xdp_xmit_zc(struct igc_ring *ring) ntu++; if (ntu == ring->count) ntu = 0; + + ring->next_to_use = ntu; + budget--; } - ring->next_to_use = ntu; if (tx_desc) { igc_flush_tx_descriptors(ring); xsk_tx_release(pool); -- 2.34.1