From patchwork Tue Dec 7 20:55:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Lobakin X-Patchwork-Id: 12662661 X-Patchwork-Delegate: kuba@kernel.org 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 ABE6CC4332F for ; Tue, 7 Dec 2021 20:56:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230209AbhLGU7w (ORCPT ); Tue, 7 Dec 2021 15:59:52 -0500 Received: from mga18.intel.com ([134.134.136.126]:4679 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229475AbhLGU7s (ORCPT ); Tue, 7 Dec 2021 15:59:48 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10191"; a="224554362" X-IronPort-AV: E=Sophos;i="5.87,295,1631602800"; d="scan'208";a="224554362" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Dec 2021 12:56:17 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.87,295,1631602800"; d="scan'208";a="605867579" Received: from irvmail001.ir.intel.com ([10.43.11.63]) by fmsmga002.fm.intel.com with ESMTP; 07 Dec 2021 12:56:12 -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 1B7Ku9ke018910; Tue, 7 Dec 2021 20:56:11 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?b?QmrDtnJuIFTDtnBlbA==?= , Maciej Fijalkowski , Michal Swiatkowski , Jeff Kirsher , Krzysztof Kazimierczak , Jithu Joseph , Andre Guedes , Vedang Patel , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH v3 net-next 1/9] i40e: don't reserve excessive XDP_PACKET_HEADROOM on XSK Rx to skb Date: Tue, 7 Dec 2021 21:55:28 +0100 Message-Id: <20211207205536.563550-2-alexandr.lobakin@intel.com> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211207205536.563550-1-alexandr.lobakin@intel.com> References: <20211207205536.563550-1-alexandr.lobakin@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org {__,}napi_alloc_skb() allocates and reserves additional NET_SKB_PAD + NET_IP_ALIGN for any skb. OTOH, i40e_construct_skb_zc() currently allocates and reserves additional `xdp->data - xdp->data_hard_start`, which is XDP_PACKET_HEADROOM for XSK frames. There's no need for that at all as the frame is post-XDP and will go only to the networking stack core. Pass the size of the actual data only to __napi_alloc_skb() and don't reserve anything. This will give enough headroom for stack processing. Fixes: 0a714186d3c0 ("i40e: add AF_XDP zero-copy Rx support") Signed-off-by: Alexander Lobakin Reviewed-by: Michal Swiatkowski --- drivers/net/ethernet/intel/i40e/i40e_xsk.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c index f08d19b8c554..9564906b7da8 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c +++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c @@ -245,13 +245,11 @@ static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring, struct sk_buff *skb; /* allocate a skb to store the frags */ - skb = __napi_alloc_skb(&rx_ring->q_vector->napi, - xdp->data_end - xdp->data_hard_start, + skb = __napi_alloc_skb(&rx_ring->q_vector->napi, datasize, GFP_ATOMIC | __GFP_NOWARN); if (unlikely(!skb)) goto out; - skb_reserve(skb, xdp->data - xdp->data_hard_start); memcpy(__skb_put(skb, datasize), xdp->data, datasize); if (metasize) skb_metadata_set(skb, metasize);