From patchwork Tue Mar 28 20:15:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jesper Dangaard Brouer X-Patchwork-Id: 13191514 X-Patchwork-Delegate: bpf@iogearbox.net 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 95A69C77B60 for ; Tue, 28 Mar 2023 20:17:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229891AbjC1UQ7 (ORCPT ); Tue, 28 Mar 2023 16:16:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59626 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229910AbjC1UQx (ORCPT ); Tue, 28 Mar 2023 16:16:53 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE63B3AB7 for ; Tue, 28 Mar 2023 13:16:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1680034563; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Btpaq0T95DzJARTIOQ/tKL2YaQOMLaE7wfp3COF2FTY=; b=W/TMywnG4pKAHjQy84EhQ0ysG5bVY3LZc9Gc3jzqmJoKyrgHC053uGdzlOl9qIrSZFuP+D b1TQlU8jEueTynEEsciuXE2yvLlhIvtDF6t83UWyZ1oPOLyMr008ncFisRwGdHCexFnymm 6c211ytM7F3k4MQIlRbGRgWYjMSToqg= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-231-g5Rjh4JJNqSdboiLnOtOPQ-1; Tue, 28 Mar 2023 16:16:00 -0400 X-MC-Unique: g5Rjh4JJNqSdboiLnOtOPQ-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6B3B4101A531; Tue, 28 Mar 2023 20:15:59 +0000 (UTC) Received: from firesoul.localdomain (unknown [10.45.242.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id 16548492C3E; Tue, 28 Mar 2023 20:15:59 +0000 (UTC) Received: from [10.1.1.1] (localhost [IPv6:::1]) by firesoul.localdomain (Postfix) with ESMTP id 3616E30736C72; Tue, 28 Mar 2023 22:15:58 +0200 (CEST) Subject: [PATCH bpf RFC 1/4] xdp: rss hash types representation From: Jesper Dangaard Brouer To: bpf@vger.kernel.org Cc: Jesper Dangaard Brouer , netdev@vger.kernel.org, Stanislav Fomichev , martin.lau@kernel.org, ast@kernel.org, daniel@iogearbox.net, alexandr.lobakin@intel.com, larysa.zaremba@intel.com, xdp-hints@xdp-project.net, anthony.l.nguyen@intel.com, yoong.siang.song@intel.com, boon.leong.ong@intel.com, intel-wired-lan@lists.osuosl.org, pabeni@redhat.com, jesse.brandeburg@intel.com, kuba@kernel.org, edumazet@google.com, john.fastabend@gmail.com, hawk@kernel.org, davem@davemloft.net Date: Tue, 28 Mar 2023 22:15:58 +0200 Message-ID: <168003455815.3027256.7575362149566382055.stgit@firesoul> In-Reply-To: <168003451121.3027256.13000250073816770554.stgit@firesoul> References: <168003451121.3027256.13000250073816770554.stgit@firesoul> User-Agent: StGit/1.4 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net X-Patchwork-State: RFC The RSS hash type specifies what portion of packet data NIC hardware used when calculating RSS hash value. The RSS types are focused on Internet traffic protocols at OSI layers L3 and L4. L2 (e.g. ARP) often get hash value zero and no RSS type. For L3 focused on IPv4 vs. IPv6, and L4 primarily TCP vs UDP, but some hardware supports SCTP. Hardware RSS types are differently encoded for each hardware NIC. Most hardware represent RSS hash type as a number. Determining L3 vs L4 often requires a mapping table as there often isn't a pattern or sorting according to ISO layer. The patch introduce a XDP RSS hash type (xdp_rss_hash_type) that can both be seen as a number that is ordered according by ISO layer, and can be bit masked to separate IPv4 and IPv6 types for L4 protocols. Room is available for extending later while keeping these properties. This maps and unifies difference to hardware specific hashes. This proposal change the kfunc API bpf_xdp_metadata_rx_hash() to return this RSS hash type on success. Signed-off-by: Jesper Dangaard Brouer --- include/net/xdp.h | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ net/core/xdp.c | 4 +++- 2 files changed, 54 insertions(+), 1 deletion(-) diff --git a/include/net/xdp.h b/include/net/xdp.h index 5393b3ebe56e..63f462f5ea7f 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -8,6 +8,7 @@ #include /* skb_shared_info */ #include +#include /** * DOC: XDP RX-queue information @@ -396,6 +397,56 @@ XDP_METADATA_KFUNC_xxx MAX_XDP_METADATA_KFUNC, }; +/* For partitioning of xdp_rss_hash_type */ +#define RSS_L3 GENMASK(2,0) /* 3-bits = values between 1-7 */ +#define L4_BIT BIT(3) /* 1-bit - L4 indication */ +#define RSS_L4_IPV4 GENMASK(6,4) /* 3-bits */ +#define RSS_L4_IPV6 GENMASK(9,7) /* 3-bits */ +#define RSS_L4 GENMASK(9,3) /* = 7-bits - covering L4 IPV4+IPV6 */ +#define L4_IPV6_EX_BIT BIT(9) /* 1-bit - L4 IPv6 with Extension hdr */ + /* 11-bits in total */ + +/* The XDP RSS hash type (xdp_rss_hash_type) can both be seen as a number that + * is ordered according by ISO layer, and can be bit masked to separate IPv4 and + * IPv6 types for L4 protocols. Room is available for extending later while + * keeping above properties, as this need to cover NIC hardware RSS types. + */ +enum xdp_rss_hash_type { + XDP_RSS_TYPE_NONE = 0, + XDP_RSS_TYPE_L2 = XDP_RSS_TYPE_NONE, + + XDP_RSS_TYPE_L3_MASK = RSS_L3, + XDP_RSS_TYPE_L3_IPV4 = FIELD_PREP_CONST(RSS_L3, 1), + XDP_RSS_TYPE_L3_IPV6 = FIELD_PREP_CONST(RSS_L3, 2), + XDP_RSS_TYPE_L3_IPV6_EX = FIELD_PREP_CONST(RSS_L3, 4), + + XDP_RSS_TYPE_L4_MASK = RSS_L4, + XDP_RSS_TYPE_L4_SHIFT = __bf_shf(RSS_L4), + XDP_RSS_TYPE_L4_MASK_EX = RSS_L4 | L4_IPV6_EX_BIT, + + XDP_RSS_TYPE_L4_IPV4_MASK = RSS_L4_IPV4, + XDP_RSS_TYPE_L4_BIT = L4_BIT, + XDP_RSS_TYPE_L4_IPV4_TCP = L4_BIT|FIELD_PREP_CONST(RSS_L4_IPV4, 1), + XDP_RSS_TYPE_L4_IPV4_UDP = L4_BIT|FIELD_PREP_CONST(RSS_L4_IPV4, 2), + XDP_RSS_TYPE_L4_IPV4_SCTP = L4_BIT|FIELD_PREP_CONST(RSS_L4_IPV4, 3), + + XDP_RSS_TYPE_L4_IPV6_MASK = RSS_L4_IPV6, + XDP_RSS_TYPE_L4_IPV6_TCP = L4_BIT|FIELD_PREP_CONST(RSS_L4_IPV6, 1), + XDP_RSS_TYPE_L4_IPV6_UDP = L4_BIT|FIELD_PREP_CONST(RSS_L4_IPV6, 2), + XDP_RSS_TYPE_L4_IPV6_SCTP = L4_BIT|FIELD_PREP_CONST(RSS_L4_IPV6, 3), + + XDP_RSS_TYPE_L4_IPV6_EX_MASK = L4_IPV6_EX_BIT, + XDP_RSS_TYPE_L4_IPV6_TCP_EX = XDP_RSS_TYPE_L4_IPV6_TCP |L4_IPV6_EX_BIT, + XDP_RSS_TYPE_L4_IPV6_UDP_EX = XDP_RSS_TYPE_L4_IPV6_UDP |L4_IPV6_EX_BIT, + XDP_RSS_TYPE_L4_IPV6_SCTP_EX = XDP_RSS_TYPE_L4_IPV6_SCTP|L4_IPV6_EX_BIT, +}; +#undef RSS_L3 +#undef L4_BIT +#undef RSS_L4_IPV4 +#undef RSS_L4_IPV6 +#undef RSS_L4 +#undef L4_IPV6_EX_BIT + #ifdef CONFIG_NET u32 bpf_xdp_metadata_kfunc_id(int id); bool bpf_dev_bound_kfunc_id(u32 btf_id); diff --git a/net/core/xdp.c b/net/core/xdp.c index 7133017bcd74..81d41df30695 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -721,12 +721,14 @@ __bpf_kfunc int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx, u64 *tim * @hash: Return value pointer. * * Return: - * * Returns 0 on success or ``-errno`` on error. + * * Returns (positive) RSS hash **type** on success or ``-errno`` on error. + * * ``enum xdp_rss_hash_type`` : RSS hash type * * ``-EOPNOTSUPP`` : means device driver doesn't implement kfunc * * ``-ENODATA`` : means no RX-hash available for this frame */ __bpf_kfunc int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, u32 *hash) { + BTF_TYPE_EMIT(enum xdp_rss_hash_type); return -EOPNOTSUPP; }