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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Willem de Bruijn , Donald Hunter , Jonathan Corbet , Bjorn Topel , "Karlsson, Magnus" , "Fijalkowski, Maciej" , Jonathan Lemon , Andrew Lunn , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , "Damato, Joe" , Stanislav Fomichev , Xuan Zhuo , Mina Almasry , Daniel Jurgens , 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 , "Nguyen, Anthony L" , "Kitszel, Przemyslaw" , "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: Re: [PATCH bpf-next v6 4/4] igc: Add launch time support to XDP ZC Message-ID: References: <20250116155350.555374-1-yoong.siang.song@intel.com> <20250116155350.555374-5-yoong.siang.song@intel.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On 01/23, Florian Bezdeka wrote: > Hi all, > > On Thu, 2025-01-23 at 16:41 +0000, Song, Yoong Siang wrote: > > On Thursday, January 23, 2025 11:40 PM, Bouska, Zdenek wrote: > > > > > > Hi Siang, > > > > > > I tested this patch series on 6.13 with Intel I226-LM (rev 04). > > > > > > I also applied patch "selftests/bpf: Actuate tx_metadata_len in xdp_hw_metadata" [1] > > > and "selftests/bpf: Enable Tx hwtstamp in xdp_hw_metadata" [2] so that TX timestamps > > > work. > > > > > > HW RX-timestamp was small (0.5956 instead of 1737373125.5956): > > > > > > HW RX-time: 595572448 (sec:0.5956) delta to User RX-time sec:1737373124.9873 (1737373124987318.750 usec) > > > XDP RX-time: 1737373125582798388 (sec:1737373125.5828) delta to User RX-time sec:0.0001 (92.733 usec) > > > > > > Igc's raw HW RX-timestamp in front of frame data was overwritten by BPF program on > > > line 90 in tools/testing/selftests/bpf: meta->hint_valid = 0; > > > > > > "HW timestamp has been copied into local variable" comment is outdated on > > > line 2813 in drivers/net/ethernet/intel/igc/igc_main.c after > > > commit 069b142f5819 igc: Add support for PTP .getcyclesx64() [3]. > > > > > > Workaround is to add unused data to xdp_meta struct: > > > > > > --- a/tools/testing/selftests/bpf/xdp_metadata.h > > > +++ b/tools/testing/selftests/bpf/xdp_metadata.h > > > @@ -49,4 +49,5 @@ struct xdp_meta { > > > __s32 rx_vlan_tag_err; > > > }; > > > enum xdp_meta_field hint_valid; > > > + __u8 avoid_IGC_TS_HDR_LEN[16]; > > > }; > > > > > > > Hi Zdenek Bouska, > > > > Thanks for your help on testing this patch set. > > You are right, there is some issue with the Rx hw timestamp, > > I will submit the bug fix patch when the solution is finalized, > > but the fix will not be part of this launch time patch set. > > Until then, you can continue to use your WA. > > I think there is no simple fix for that. That needs some discussion > around the "expectations" to the headroom / meta data area in front of > the actual packet data. By 'simple' you mean without some new UAPI to signal the size of that 'reserved area' by the driver? I don't see any other easy way out as well :-/ From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BEEC4C0218B for ; Thu, 23 Jan 2025 19:49:35 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 7007A84040; Thu, 23 Jan 2025 19:49:35 +0000 (UTC) X-Virus-Scanned: amavis at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP id AokZHk1ll2o6; Thu, 23 Jan 2025 19:49:34 +0000 (UTC) X-Comment: SPF check N/A for local connections - client-ip=140.211.166.142; helo=lists1.osuosl.org; envelope-from=intel-wired-lan-bounces@osuosl.org; receiver= DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org A8E9F83FEE DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=osuosl.org; s=default; t=1737661774; bh=/qLickY1e0ujLI7bpuAPKBg3ra7SxF8sIpaNTGdpk/E=; h=Date:From:To:Cc:References:In-Reply-To:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=ZtZhZ1dDnUnpOIKdI22IdKkVXwcZUt2ZTy/WPQhwzt9E7NOuuOJFgmsDexS+3D+JO 49qVkslG2NMIshJpvI/ErEuXAij30/D7F0f9tNmwhorgnb5Dt1jANOmX7oGF89LJ3Q jLDCWpNPb53bsWUCIynG7sgY+tCqBMMfwk+gjtsVZvdyrYln0Jt7ajypI48Ptd7ZCj u4keTvTgm0RKDxiMrE3YGE1LWPCOH9yF94Nfi8d1FsYAL6M6q8XGfMqz/moj2SJqt+ QvJy/Is+jZ0YNgbjF8aKMPVGt9d5/PrszuMh9aDPc4bo4aBuf8YcATHjDkiR5Sl2ou 18n3vjrrhUX1g== Received: from lists1.osuosl.org (lists1.osuosl.org [140.211.166.142]) by smtp1.osuosl.org (Postfix) with ESMTP id A8E9F83FEE; Thu, 23 Jan 2025 19:49:34 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [IPv6:2605:bc80:3010::133]) by lists1.osuosl.org (Postfix) with ESMTP id 15EDC959 for ; Thu, 23 Jan 2025 19:49:33 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 03DE240296 for ; Thu, 23 Jan 2025 19:49:33 +0000 (UTC) X-Virus-Scanned: amavis at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP id kJxkbrrANVDY for ; Thu, 23 Jan 2025 19:49:32 +0000 (UTC) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=2607:f8b0:4864:20::636; helo=mail-pl1-x636.google.com; envelope-from=stfomichev@gmail.com; receiver= DMARC-Filter: OpenDMARC Filter v1.4.2 smtp2.osuosl.org 06D0A40176 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org 06D0A40176 Received: from mail-pl1-x636.google.com (mail-pl1-x636.google.com [IPv6:2607:f8b0:4864:20::636]) by smtp2.osuosl.org (Postfix) with ESMTPS id 06D0A40176 for ; Thu, 23 Jan 2025 19:49:31 +0000 (UTC) Received: by mail-pl1-x636.google.com with SMTP id d9443c01a7336-2165cb60719so23307355ad.0 for ; Thu, 23 Jan 2025 11:49:31 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1737661771; x=1738266571; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=/qLickY1e0ujLI7bpuAPKBg3ra7SxF8sIpaNTGdpk/E=; b=Jv/RTMrwpgYqpucV7cGLSHYo0IGP7VELoeBYmltoR1jBUnGaUxI2Hlthy7Ebv2CatM 2iIN/M5gKMQF2y1FXzsYZ06xi0dvu7vsv0si5AD3qvSAhkNH7f889tD12qZvNABtTmkK l8PST1J+Ab/vGYrXPsNp+FlOExwZIaGEAAWMuEUpatLviRdYOkuRyKWN91IAv8K/0KAJ Toe8Nc67/U185y9mxVVpzEKp6vFPhFfFuc/v0BiyEvzbVKqkdsZlDznayMt65tPIOaTd V+4rotnvRYJEQsY3P+whE1b4yhm+/UmejeR1OI2Sm9aUgLTRCkBvLkA1xW8WX4R5zTbI zZqA== X-Forwarded-Encrypted: i=1; AJvYcCWO4e0JqT+Cbcc38qy5jV4z6NmsZGNFa8UQgy4fTdlGPdifZEFQGCmqxmOWcORnLgCEfijFQkqbEXCldpzqbko=@lists.osuosl.org X-Gm-Message-State: AOJu0Yw9D+Tj2fj0SsJnvd5Glj41/qJ6Fv6P5+a1Tg1R7VTIX/jPGXM+ eCNf7TlamLlOpBd3gPupGC6glyyRxlpXhyt1HNouVYosNC+TvLtzReMlNrE= X-Gm-Gg: ASbGncsOfshLQ0ysIqVlrbsiAGQdQ1pBcag28FPZ4ym4yZt+KU0UFbX2RF0YWuMzUc0 cBLyX6FjOQW/ApWDqXOzfWebRkqnoSmXkKNhb2KbNULhG3NEf2MbGhPaz7NPEPEhOi3rnVgEK0j 2wiFyZ/jABKCm9GtL2JDFdLojA0IO/kytoPyRfUQGl2QwCap/3J0syHuS/Z2FN9fdcckOwqwXTR NnGw0qPmRcMLQxZ9dBzaUHpZKOyMXXmZ1FFmHHoy/s6ohq8jzIMIiLSJvdGV3nSd3NwGI66Y7or ZmVU X-Google-Smtp-Source: AGHT+IESeNKwX2zcipFaXoMlvYsxaD0Oto3RCfSnVHPTxJyo13u3XHbde1U83PRnjPUOPMjYL0fFMw== X-Received: by 2002:a17:903:988:b0:216:7ee9:220b with SMTP id d9443c01a7336-21c35530048mr461405425ad.22.1737661771206; Thu, 23 Jan 2025 11:49:31 -0800 (PST) Received: from localhost ([2601:646:9e00:f56e:123b:cea3:439a:b3e3]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-21da4141436sm2728275ad.134.2025.01.23.11.49.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 23 Jan 2025 11:49:30 -0800 (PST) Date: Thu, 23 Jan 2025 11:49:30 -0800 From: Stanislav Fomichev To: Florian Bezdeka Cc: "Song, Yoong Siang" , "Bouska, Zdenek" , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Willem de Bruijn , Donald Hunter , Jonathan Corbet , Bjorn Topel , "Karlsson, Magnus" , "Fijalkowski, Maciej" , Jonathan Lemon , Andrew Lunn , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , "Damato, Joe" , Stanislav Fomichev , Xuan Zhuo , Mina Almasry , Daniel Jurgens , 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 , "Nguyen, Anthony L" , "Kitszel, Przemyslaw" , "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" Message-ID: References: <20250116155350.555374-1-yoong.siang.song@intel.com> <20250116155350.555374-5-yoong.siang.song@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1737661771; x=1738266571; darn=lists.osuosl.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=/qLickY1e0ujLI7bpuAPKBg3ra7SxF8sIpaNTGdpk/E=; b=fdb+j9FZ70S3LQK2S1OKdghi0VQ/hjdU/URZRTpRhfcfhrOfihqKHyxlRveXFD3Q6z 4XPQzNoyI21grEySuO6fagFIOcbXpT6uDAcVttd0XXFBXCrHinb8ZbYDRtlp4eEh7+Tp O+8VKVmgIldE8r9n1az9+FN01dGv9MH0L1CxywILfyH3zOh/AuGYTsuWxij1kkO1EOEE IY8KvWuBvGIicuH8g7/jmmcRbTO0CV9z/60Or2KMHR6Ch1Xq2VpTYxR78rCcoezl8nFf IXy0D9niknl3RGang9vJZwnOMwNjZSZNMbql8xpJ0YS84QmmgFAG7TpOVQus7wnYUYu8 HObQ== X-Mailman-Original-Authentication-Results: smtp2.osuosl.org; dmarc=pass (p=none dis=none) header.from=gmail.com X-Mailman-Original-Authentication-Results: smtp2.osuosl.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20230601 header.b=fdb+j9FZ Subject: Re: [Intel-wired-lan] [PATCH bpf-next v6 4/4] igc: Add launch time support to XDP ZC X-BeenThere: intel-wired-lan@osuosl.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Intel Wired Ethernet Linux Kernel Driver Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-wired-lan-bounces@osuosl.org Sender: "Intel-wired-lan" On 01/23, Florian Bezdeka wrote: > Hi all, > > On Thu, 2025-01-23 at 16:41 +0000, Song, Yoong Siang wrote: > > On Thursday, January 23, 2025 11:40 PM, Bouska, Zdenek wrote: > > > > > > Hi Siang, > > > > > > I tested this patch series on 6.13 with Intel I226-LM (rev 04). > > > > > > I also applied patch "selftests/bpf: Actuate tx_metadata_len in xdp_hw_metadata" [1] > > > and "selftests/bpf: Enable Tx hwtstamp in xdp_hw_metadata" [2] so that TX timestamps > > > work. > > > > > > HW RX-timestamp was small (0.5956 instead of 1737373125.5956): > > > > > > HW RX-time: 595572448 (sec:0.5956) delta to User RX-time sec:1737373124.9873 (1737373124987318.750 usec) > > > XDP RX-time: 1737373125582798388 (sec:1737373125.5828) delta to User RX-time sec:0.0001 (92.733 usec) > > > > > > Igc's raw HW RX-timestamp in front of frame data was overwritten by BPF program on > > > line 90 in tools/testing/selftests/bpf: meta->hint_valid = 0; > > > > > > "HW timestamp has been copied into local variable" comment is outdated on > > > line 2813 in drivers/net/ethernet/intel/igc/igc_main.c after > > > commit 069b142f5819 igc: Add support for PTP .getcyclesx64() [3]. > > > > > > Workaround is to add unused data to xdp_meta struct: > > > > > > --- a/tools/testing/selftests/bpf/xdp_metadata.h > > > +++ b/tools/testing/selftests/bpf/xdp_metadata.h > > > @@ -49,4 +49,5 @@ struct xdp_meta { > > > __s32 rx_vlan_tag_err; > > > }; > > > enum xdp_meta_field hint_valid; > > > + __u8 avoid_IGC_TS_HDR_LEN[16]; > > > }; > > > > > > > Hi Zdenek Bouska, > > > > Thanks for your help on testing this patch set. > > You are right, there is some issue with the Rx hw timestamp, > > I will submit the bug fix patch when the solution is finalized, > > but the fix will not be part of this launch time patch set. > > Until then, you can continue to use your WA. > > I think there is no simple fix for that. That needs some discussion > around the "expectations" to the headroom / meta data area in front of > the actual packet data. By 'simple' you mean without some new UAPI to signal the size of that 'reserved area' by the driver? I don't see any other easy way out as well :-/