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Thu, 18 Sep 2025 00:41:52 +0000 (UTC) X-Virus-Scanned: amavis at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP id 0Nv9_WWHFX9y for ; Thu, 18 Sep 2025 00:41:51 +0000 (UTC) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=2600:3c0a:e001:78e:0:1991:8:25; helo=sea.source.kernel.org; envelope-from=kuba@kernel.org; receiver= DMARC-Filter: OpenDMARC Filter v1.4.2 smtp4.osuosl.org ECDDE414B2 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org ECDDE414B2 Received: from sea.source.kernel.org (sea.source.kernel.org [IPv6:2600:3c0a:e001:78e:0:1991:8:25]) by smtp4.osuosl.org (Postfix) with ESMTPS id ECDDE414B2 for ; Thu, 18 Sep 2025 00:41:50 +0000 (UTC) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 4055840282; Thu, 18 Sep 2025 00:41:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 88EECC4CEE7; Thu, 18 Sep 2025 00:41:49 +0000 (UTC) Date: Wed, 17 Sep 2025 17:41:48 -0700 From: Jakub Kicinski To: Vadim Fedorenko Cc: Andrew Lunn , Michael Chan , Pavan Chebbi , Tariq Toukan , Gal Pressman , intel-wired-lan@lists.osuosl.org, Donald Hunter , Carolina Jubran , Paolo Abeni , Simon Horman , netdev@vger.kernel.org Message-ID: <20250917174148.0c909f92@kernel.org> In-Reply-To: <20250916191257.13343-2-vadim.fedorenko@linux.dev> References: <20250916191257.13343-1-vadim.fedorenko@linux.dev> <20250916191257.13343-2-vadim.fedorenko@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1758156110; bh=SKSm9QwVf25v16NYpqpomgrgFTSL2lDCp6R788YSyvA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=eGCTo23z7YO+rA5ArYwaSo0h15bg18cZQqLPiT7cmDbu+0H1i0+mFQom1njtbw64P fKou2oiV8rjChCTsXuQ/U3NPOFlGKUXpYHJbSk60cpvuT5IKx6adsTCCF+Pb4iVDoa mCBaN9Z4k7aIrwoJBrihRM1c1Eug8EuAA2fg+5dY3ueuclkmOyH83clLoqU2LP30Ii y+ul7ckvE+kNsbhV5jYV8bZSnLcLn1mX+Dj6AQygeEmakgKx6XHPVYwdXe/aRYL1Ib RwqyuyMsYoSJ1npsOycgqK6LJdMMroMuifgeddpR/NKgmF+4ZYakjn3Njcive+SY/V mDFjIBnDqF6dQ== X-Mailman-Original-Authentication-Results: smtp4.osuosl.org; dmarc=pass (p=quarantine dis=none) header.from=kernel.org X-Mailman-Original-Authentication-Results: smtp4.osuosl.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=eGCTo23z Subject: Re: [Intel-wired-lan] [PATCH net-next v3 1/4] ethtool: add FEC bins histogram report 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 Tue, 16 Sep 2025 19:12:54 +0000 Vadim Fedorenko wrote: > IEEE 802.3ck-2022 defines counters for FEC bins and 802.3df-2024 > clarifies it a bit further. Implement reporting interface through as > addition to FEC stats available in ethtool. > diff --git a/Documentation/netlink/specs/ethtool.yaml b/Documentation/netlink/specs/ethtool.yaml > index 7a7594713f1f..de5008266884 100644 > --- a/Documentation/netlink/specs/ethtool.yaml > +++ b/Documentation/netlink/specs/ethtool.yaml > @@ -1219,6 +1219,23 @@ attribute-sets: > name: udp-ports > type: nest > nested-attributes: tunnel-udp > + - > + name: fec-hist > + attr-cnt-name: __ethtool-a-fec-hist-cnt s/__/--/ > + attributes: > + - > + name: bin-low > + type: u32 > + - > + name: bin-high > + type: u32 We should add some doc: strings here so that the important info like which one is inclusive is rendered right in the API reference > + - > + name: bin-val > + type: uint > + - > + name: bin-val-per-lane > + type: binary probably good to doc this too > + sub-type: u64 > - > name: fec-stat > attr-cnt-name: __ethtool-a-fec-stat-cnt > @@ -1242,6 +1259,11 @@ attribute-sets: > name: corr-bits > type: binary > sub-type: u64 > + - > + name: hist > + type: nest > + multi-attr: True > + nested-attributes: fec-hist > - > name: fec > attr-cnt-name: __ethtool-a-fec-cnt > diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst > index ab20c644af24..b270886c5f5d 100644 > --- a/Documentation/networking/ethtool-netlink.rst > +++ b/Documentation/networking/ethtool-netlink.rst > @@ -1541,6 +1541,11 @@ Drivers fill in the statistics in the following structure: > .. kernel-doc:: include/linux/ethtool.h > :identifiers: ethtool_fec_stats > > +Statistics may have FEC bins histogram attribute ``ETHTOOL_A_FEC_STAT_HIST`` > +as defined in IEEE 802.3ck-2022 and 802.3df-2024. Nested attributes will have > +the range of FEC errors in the bin (inclusive) and the amount of error events > +in the bin. Does this sound better? Optional ``ETHTOOL_A_FEC_STAT_HIST`` attributes form a FEC error histogram, as defined in IEEE 802.3ck-2022 and 802.3df-2024 (histogram of number of errors within a single FEC block). Each ``ETHTOOL_A_FEC_STAT_HIST`` entry contains error count (optionally also broken down by SerDes lane) as well as metadata about the bin. Bin range (low, high) is inclusive. > static void > -nsim_get_fec_stats(struct net_device *dev, struct ethtool_fec_stats *fec_stats) > +nsim_get_fec_stats(struct net_device *dev, struct ethtool_fec_stats *fec_stats, > + struct ethtool_fec_hist *hist) > { > + struct ethtool_fec_hist_value *values = hist->values; > + > + hist->ranges = netdevsim_fec_ranges; > + > fec_stats->corrected_blocks.total = 123; > fec_stats->uncorrectable_blocks.total = 4; > + > + values[0].bin_value = 445; Bin 0 had per lane breakdown, can't core add up the lanes for the driver? > + values[1].bin_value = 12; > + values[2].bin_value = 2; > + values[0].bin_value_per_lane[0] = 125; > + values[0].bin_value_per_lane[1] = 120; > + values[0].bin_value_per_lane[2] = 100; > + values[0].bin_value_per_lane[3] = 100; > } > +/** > + * struct ethtool_fec_hist_range - error bits range for FEC bins histogram Don't say "FEC bin histogram" I think the word histogram implies that the data is bin'ed up. > + * statistics > + * @low: low bound of the bin (inclusive) > + * @high: high bound of the bin (inclusive) > + */ > @@ -113,7 +114,11 @@ static int fec_prepare_data(const struct ethnl_req_info *req_base, > struct ethtool_fec_stats stats; > > ethtool_stats_init((u64 *)&stats, sizeof(stats) / 8); > - dev->ethtool_ops->get_fec_stats(dev, &stats); > + ethtool_stats_init((u64 *)data->fec_stat_hist.values, > + ETHTOOL_FEC_HIST_MAX * > + sizeof(struct ethtool_fec_hist_value) / 8); sizeof(data->fec_stat_hist.values) / 8 would save you the multiplication? > + dev->ethtool_ops->get_fec_stats(dev, &stats, > + &data->fec_stat_hist); > > fec_stats_recalc(&data->corr, &stats.corrected_blocks); > fec_stats_recalc(&data->uncorr, &stats.uncorrectable_blocks); > +static int fec_put_hist(struct sk_buff *skb, const struct ethtool_fec_hist *hist) over 80 chars, please wrap (checkpatch --max-line-length=80) > +{ > + const struct ethtool_fec_hist_range *ranges = hist->ranges; > + const struct ethtool_fec_hist_value *values = hist->values; > + struct nlattr *nest; > + int i, j; > + > + if (!ranges) > + return 0; > + > + for (i = 0; i < ETHTOOL_FEC_HIST_MAX; i++) { > + if (i && !ranges[i].low && !ranges[i].high) low and high should probably be unsigned now > + break; > + > + if (WARN_ON_ONCE(values[i].bin_value == ETHTOOL_STAT_NOT_SET)) > + break; > + > + nest = nla_nest_start(skb, ETHTOOL_A_FEC_STAT_HIST); > + if (!nest) > + return -EMSGSIZE; > + > + if (nla_put_u32(skb, ETHTOOL_A_FEC_HIST_BIN_LOW, > + ranges[i].low) || > + nla_put_u32(skb, ETHTOOL_A_FEC_HIST_BIN_HIGH, > + ranges[i].high) || > + nla_put_uint(skb, ETHTOOL_A_FEC_HIST_BIN_VAL, > + values[i].bin_value)) > + goto err_cancel_hist; > + for (j = 0; j < ETHTOOL_MAX_LANES; j++) { > + if (values[i].bin_value_per_lane[j] == ETHTOOL_STAT_NOT_SET) You know, bin_value could be 'sum', and bin_value_per_lane could be simply 'per_lane'. > + break; > + } {} brackets unnecessary > + if (j && nla_put_64bit(skb, ETHTOOL_A_FEC_HIST_BIN_VAL_PER_LANE, > + sizeof(u64) * j, > + values[i].bin_value_per_lane, > + ETHTOOL_A_FEC_STAT_PAD)) > + goto err_cancel_hist; > + > + nla_nest_end(skb, nest); > + } > + > + return 0; > + > +err_cancel_hist: > + nla_nest_cancel(skb, nest); > + return -EMSGSIZE; > +} We need a selftest. Add a case to stats.py and do basic sanity checking on what the kernel spits out? Maybe 2 test cases - one for overall and one for per-lane, cause mlx5 doesn't have per lane and we'd like the test to pass there. From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 7EFAC4315A for ; Thu, 18 Sep 2025 00:41:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758156110; cv=none; b=Q2j9r3A9BNTi6z3qaJteMEhpkO5s4Py5yy2M1Kfh4FI7g44ZOSln9txsqU1YNbV8KLEesySh62yWs+uK4SIe3BqeDLfYUKM+uHyaAGDR69rXssyyEQyCPfMIalJ4MovFXwyx7wpiHEcXi0+/Sm5u45y4Ek072v+e/laf1iaJb4k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758156110; c=relaxed/simple; bh=SKSm9QwVf25v16NYpqpomgrgFTSL2lDCp6R788YSyvA=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=PiWuT8t5uoYVMXIdnNK0fRku+NhtL/87+O9CmLxrpf8Rw8mBoHOpembttTfbdSkSlACDgYgeUxEBZ7hhz3E5lq8w/0NZr2jgycNAWjr1IQRutv1wG6FSI88Du3KqDRq+HS6khh0VP9XyNDtkYeHrR77pOHeGIKClocONhnvRUCQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eGCTo23z; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="eGCTo23z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 88EECC4CEE7; Thu, 18 Sep 2025 00:41:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1758156110; bh=SKSm9QwVf25v16NYpqpomgrgFTSL2lDCp6R788YSyvA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=eGCTo23z7YO+rA5ArYwaSo0h15bg18cZQqLPiT7cmDbu+0H1i0+mFQom1njtbw64P fKou2oiV8rjChCTsXuQ/U3NPOFlGKUXpYHJbSk60cpvuT5IKx6adsTCCF+Pb4iVDoa mCBaN9Z4k7aIrwoJBrihRM1c1Eug8EuAA2fg+5dY3ueuclkmOyH83clLoqU2LP30Ii y+ul7ckvE+kNsbhV5jYV8bZSnLcLn1mX+Dj6AQygeEmakgKx6XHPVYwdXe/aRYL1Ib RwqyuyMsYoSJ1npsOycgqK6LJdMMroMuifgeddpR/NKgmF+4ZYakjn3Njcive+SY/V mDFjIBnDqF6dQ== Date: Wed, 17 Sep 2025 17:41:48 -0700 From: Jakub Kicinski To: Vadim Fedorenko Cc: Andrew Lunn , Michael Chan , Pavan Chebbi , Tariq Toukan , Gal Pressman , intel-wired-lan@lists.osuosl.org, Donald Hunter , Carolina Jubran , Paolo Abeni , Simon Horman , netdev@vger.kernel.org Subject: Re: [PATCH net-next v3 1/4] ethtool: add FEC bins histogram report Message-ID: <20250917174148.0c909f92@kernel.org> In-Reply-To: <20250916191257.13343-2-vadim.fedorenko@linux.dev> References: <20250916191257.13343-1-vadim.fedorenko@linux.dev> <20250916191257.13343-2-vadim.fedorenko@linux.dev> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Tue, 16 Sep 2025 19:12:54 +0000 Vadim Fedorenko wrote: > IEEE 802.3ck-2022 defines counters for FEC bins and 802.3df-2024 > clarifies it a bit further. Implement reporting interface through as > addition to FEC stats available in ethtool. > diff --git a/Documentation/netlink/specs/ethtool.yaml b/Documentation/netlink/specs/ethtool.yaml > index 7a7594713f1f..de5008266884 100644 > --- a/Documentation/netlink/specs/ethtool.yaml > +++ b/Documentation/netlink/specs/ethtool.yaml > @@ -1219,6 +1219,23 @@ attribute-sets: > name: udp-ports > type: nest > nested-attributes: tunnel-udp > + - > + name: fec-hist > + attr-cnt-name: __ethtool-a-fec-hist-cnt s/__/--/ > + attributes: > + - > + name: bin-low > + type: u32 > + - > + name: bin-high > + type: u32 We should add some doc: strings here so that the important info like which one is inclusive is rendered right in the API reference > + - > + name: bin-val > + type: uint > + - > + name: bin-val-per-lane > + type: binary probably good to doc this too > + sub-type: u64 > - > name: fec-stat > attr-cnt-name: __ethtool-a-fec-stat-cnt > @@ -1242,6 +1259,11 @@ attribute-sets: > name: corr-bits > type: binary > sub-type: u64 > + - > + name: hist > + type: nest > + multi-attr: True > + nested-attributes: fec-hist > - > name: fec > attr-cnt-name: __ethtool-a-fec-cnt > diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst > index ab20c644af24..b270886c5f5d 100644 > --- a/Documentation/networking/ethtool-netlink.rst > +++ b/Documentation/networking/ethtool-netlink.rst > @@ -1541,6 +1541,11 @@ Drivers fill in the statistics in the following structure: > .. kernel-doc:: include/linux/ethtool.h > :identifiers: ethtool_fec_stats > > +Statistics may have FEC bins histogram attribute ``ETHTOOL_A_FEC_STAT_HIST`` > +as defined in IEEE 802.3ck-2022 and 802.3df-2024. Nested attributes will have > +the range of FEC errors in the bin (inclusive) and the amount of error events > +in the bin. Does this sound better? Optional ``ETHTOOL_A_FEC_STAT_HIST`` attributes form a FEC error histogram, as defined in IEEE 802.3ck-2022 and 802.3df-2024 (histogram of number of errors within a single FEC block). Each ``ETHTOOL_A_FEC_STAT_HIST`` entry contains error count (optionally also broken down by SerDes lane) as well as metadata about the bin. Bin range (low, high) is inclusive. > static void > -nsim_get_fec_stats(struct net_device *dev, struct ethtool_fec_stats *fec_stats) > +nsim_get_fec_stats(struct net_device *dev, struct ethtool_fec_stats *fec_stats, > + struct ethtool_fec_hist *hist) > { > + struct ethtool_fec_hist_value *values = hist->values; > + > + hist->ranges = netdevsim_fec_ranges; > + > fec_stats->corrected_blocks.total = 123; > fec_stats->uncorrectable_blocks.total = 4; > + > + values[0].bin_value = 445; Bin 0 had per lane breakdown, can't core add up the lanes for the driver? > + values[1].bin_value = 12; > + values[2].bin_value = 2; > + values[0].bin_value_per_lane[0] = 125; > + values[0].bin_value_per_lane[1] = 120; > + values[0].bin_value_per_lane[2] = 100; > + values[0].bin_value_per_lane[3] = 100; > } > +/** > + * struct ethtool_fec_hist_range - error bits range for FEC bins histogram Don't say "FEC bin histogram" I think the word histogram implies that the data is bin'ed up. > + * statistics > + * @low: low bound of the bin (inclusive) > + * @high: high bound of the bin (inclusive) > + */ > @@ -113,7 +114,11 @@ static int fec_prepare_data(const struct ethnl_req_info *req_base, > struct ethtool_fec_stats stats; > > ethtool_stats_init((u64 *)&stats, sizeof(stats) / 8); > - dev->ethtool_ops->get_fec_stats(dev, &stats); > + ethtool_stats_init((u64 *)data->fec_stat_hist.values, > + ETHTOOL_FEC_HIST_MAX * > + sizeof(struct ethtool_fec_hist_value) / 8); sizeof(data->fec_stat_hist.values) / 8 would save you the multiplication? > + dev->ethtool_ops->get_fec_stats(dev, &stats, > + &data->fec_stat_hist); > > fec_stats_recalc(&data->corr, &stats.corrected_blocks); > fec_stats_recalc(&data->uncorr, &stats.uncorrectable_blocks); > +static int fec_put_hist(struct sk_buff *skb, const struct ethtool_fec_hist *hist) over 80 chars, please wrap (checkpatch --max-line-length=80) > +{ > + const struct ethtool_fec_hist_range *ranges = hist->ranges; > + const struct ethtool_fec_hist_value *values = hist->values; > + struct nlattr *nest; > + int i, j; > + > + if (!ranges) > + return 0; > + > + for (i = 0; i < ETHTOOL_FEC_HIST_MAX; i++) { > + if (i && !ranges[i].low && !ranges[i].high) low and high should probably be unsigned now > + break; > + > + if (WARN_ON_ONCE(values[i].bin_value == ETHTOOL_STAT_NOT_SET)) > + break; > + > + nest = nla_nest_start(skb, ETHTOOL_A_FEC_STAT_HIST); > + if (!nest) > + return -EMSGSIZE; > + > + if (nla_put_u32(skb, ETHTOOL_A_FEC_HIST_BIN_LOW, > + ranges[i].low) || > + nla_put_u32(skb, ETHTOOL_A_FEC_HIST_BIN_HIGH, > + ranges[i].high) || > + nla_put_uint(skb, ETHTOOL_A_FEC_HIST_BIN_VAL, > + values[i].bin_value)) > + goto err_cancel_hist; > + for (j = 0; j < ETHTOOL_MAX_LANES; j++) { > + if (values[i].bin_value_per_lane[j] == ETHTOOL_STAT_NOT_SET) You know, bin_value could be 'sum', and bin_value_per_lane could be simply 'per_lane'. > + break; > + } {} brackets unnecessary > + if (j && nla_put_64bit(skb, ETHTOOL_A_FEC_HIST_BIN_VAL_PER_LANE, > + sizeof(u64) * j, > + values[i].bin_value_per_lane, > + ETHTOOL_A_FEC_STAT_PAD)) > + goto err_cancel_hist; > + > + nla_nest_end(skb, nest); > + } > + > + return 0; > + > +err_cancel_hist: > + nla_nest_cancel(skb, nest); > + return -EMSGSIZE; > +} We need a selftest. Add a case to stats.py and do basic sanity checking on what the kernel spits out? Maybe 2 test cases - one for overall and one for per-lane, cause mlx5 doesn't have per lane and we'd like the test to pass there.