From patchwork Wed Dec 8 14:06:54 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Lobakin X-Patchwork-Id: 12664453 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 147EFC43217 for ; Wed, 8 Dec 2021 14:07:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234786AbhLHOLL (ORCPT ); Wed, 8 Dec 2021 09:11:11 -0500 Received: from mga01.intel.com ([192.55.52.88]:2741 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234754AbhLHOLH (ORCPT ); Wed, 8 Dec 2021 09:11:07 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10191"; a="261912441" X-IronPort-AV: E=Sophos;i="5.88,189,1635231600"; d="scan'208";a="261912441" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Dec 2021 06:07:34 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,189,1635231600"; d="scan'208";a="606303931" Received: from irvmail001.ir.intel.com ([10.43.11.63]) by fmsmga002.fm.intel.com with ESMTP; 08 Dec 2021 06:07:29 -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 1B8E7Qud009548; Wed, 8 Dec 2021 14:07:27 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 , 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 1/9] i40e: don't reserve excessive XDP_PACKET_HEADROOM on XSK Rx to skb Date: Wed, 8 Dec 2021 15:06:54 +0100 Message-Id: <20211208140702.642741-2-alexandr.lobakin@intel.com> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211208140702.642741-1-alexandr.lobakin@intel.com> References: <20211208140702.642741-1-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 Acked-by: Jesper Dangaard Brouer Tested-by: Kiran Bhandare A Contingent Worker at Intel --- 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);