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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61D50C433EF for ; Wed, 8 Dec 2021 14:07:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234744AbhLHOLF (ORCPT ); Wed, 8 Dec 2021 09:11:05 -0500 Received: from mga04.intel.com ([192.55.52.120]:20809 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231363AbhLHOLF (ORCPT ); Wed, 8 Dec 2021 09:11:05 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10191"; a="236574216" X-IronPort-AV: E=Sophos;i="5.88,189,1635231600"; d="scan'208";a="236574216" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Dec 2021 06:07:33 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,189,1635231600"; d="scan'208";a="479908986" Received: from irvmail001.ir.intel.com ([10.43.11.63]) by orsmga002.jf.intel.com with ESMTP; 08 Dec 2021 06:07:28 -0800 Received: from newjersey.igk.intel.com (newjersey.igk.intel.com [10.102.20.203]) by irvmail001.ir.intel.com (8.14.3/8.13.6/MailSET/Hub) with ESMTP id 1B8E7Quc009548; Wed, 8 Dec 2021 14:07:26 GMT From: Alexander Lobakin To: intel-wired-lan@lists.osuosl.org Cc: Alexander Lobakin , Jesse Brandeburg , Tony Nguyen , "David S. Miller" , Jakub Kicinski , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , Maciej Fijalkowski , Michal Swiatkowski , Jithu Joseph , Martin KaFai Lau , Song Liu , KP Singh , Yonghong Song , Andrii Nakryiko , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH v4 net-next 0/9] net: intel: napi_alloc_skb() vs metadata Date: Wed, 8 Dec 2021 15:06:53 +0100 Message-Id: <20211208140702.642741-1-alexandr.lobakin@intel.com> X-Mailer: git-send-email 2.33.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org This is an interpolation of [0] to other Intel Ethernet drivers (and is (re)based on its code). The main aim is to keep XDP metadata not only in case with build_skb(), but also when we do napi_alloc_skb() + memcpy(). All Intel drivers suffers from the same here: - metadata gets lost on XDP_PASS in legacy-rx; - excessive headroom allocation on XSK Rx to skbs; - metadata gets lost on XSK Rx to skbs. Those get especially actual in XDP Hints upcoming. I couldn't have addressed the first one for all Intel drivers due to that they don't reserve any headroom for now in legacy-rx mode even with XDP enabled. This is hugely wrong, but requires quite a bunch of work and a separate series. Luckily, ice doesn't suffer from that. igc has 1 and 3 already fixed in [0]. >From v3 ([1]): - fix driver name and ixgbe_construct_skb() function name in the commit message of #9 (Jesper); - no functional changes. >From v2 (unreleased upstream): - tweaked 007 to pass bi->xdp directly and simplify code (Maciej); - picked Michal's Reviewed-by. >From v1 (unreleased upstream): - drop "fixes" of legacy-rx for i40e, igb and ixgbe since they have another flaw regarding headroom (see above); - drop igc cosmetic fixes since they landed upstream incorporated into Jesper's commits; - picked one Acked-by from Maciej. [0] https://lore.kernel.org/netdev/163700856423.565980.10162564921347693758.stgit@firesoul [1] https://lore.kernel.org/netdev/20211207205536.563550-1-alexandr.lobakin@intel.com Alexander Lobakin (9): i40e: don't reserve excessive XDP_PACKET_HEADROOM on XSK Rx to skb i40e: respect metadata on XSK Rx to skb ice: respect metadata in legacy-rx/ice_construct_skb() ice: don't reserve excessive XDP_PACKET_HEADROOM on XSK Rx to skb ice: respect metadata on XSK Rx to skb igc: don't reserve excessive XDP_PACKET_HEADROOM on XSK Rx to skb ixgbe: pass bi->xdp to ixgbe_construct_skb_zc() directly ixgbe: don't reserve excessive XDP_PACKET_HEADROOM on XSK Rx to skb ixgbe: respect metadata on XSK Rx to skb drivers/net/ethernet/intel/i40e/i40e_xsk.c | 16 +++++++----- drivers/net/ethernet/intel/ice/ice_txrx.c | 15 ++++++++--- drivers/net/ethernet/intel/ice/ice_xsk.c | 16 +++++++----- drivers/net/ethernet/intel/igc/igc_main.c | 13 +++++----- drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c | 27 ++++++++++++-------- 5 files changed, 54 insertions(+), 33 deletions(-) -- Testing hints: Setup an XDP and AF_XDP program which will prepend metadata at the front of the frames and return XDP_PASS, then check that metadata is present after frames reach kernel network stack. -- 2.33.1