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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C3035C04ABB for ; Wed, 12 Sep 2018 03:17:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8800420882 for ; Wed, 12 Sep 2018 03:17:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8800420882 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728096AbeILIUF (ORCPT ); Wed, 12 Sep 2018 04:20:05 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:44548 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726027AbeILIUF (ORCPT ); Wed, 12 Sep 2018 04:20:05 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 3BD4340241C0; Wed, 12 Sep 2018 03:17:41 +0000 (UTC) Received: from jason-ThinkPad-T450s.redhat.com (ovpn-12-130.pek2.redhat.com [10.72.12.130]) by smtp.corp.redhat.com (Postfix) with ESMTP id 89E1B2027EA4; Wed, 12 Sep 2018 03:17:38 +0000 (UTC) From: Jason Wang To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, mst@redhat.com, jasowang@redhat.com Subject: [PATCH net-next V2 04/11] tuntap: simplify error handling in tun_build_skb() Date: Wed, 12 Sep 2018 11:17:02 +0800 Message-Id: <20180912031709.14112-5-jasowang@redhat.com> In-Reply-To: <20180912031709.14112-1-jasowang@redhat.com> References: <20180912031709.14112-1-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Wed, 12 Sep 2018 03:17:41 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Wed, 12 Sep 2018 03:17:41 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'jasowang@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There's no need to duplicate page get logic in each action. So this patch tries to get page and calculate the offset before processing XDP actions (except for XDP_DROP), and undo them when meet errors (we don't care the performance on errors). This will be used for factoring out XDP logic. Signed-off-by: Jason Wang --- drivers/net/tun.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 372caf7d67d9..257cf7342d54 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1701,17 +1701,13 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun, xdp_do_flush_map(); if (err) goto err_redirect; - rcu_read_unlock(); - local_bh_enable(); - return NULL; + goto out; case XDP_TX: get_page(alloc_frag->page); alloc_frag->offset += buflen; if (tun_xdp_tx(tun->dev, &xdp) < 0) goto err_redirect; - rcu_read_unlock(); - local_bh_enable(); - return NULL; + goto out; case XDP_PASS: delta = orig_data - xdp.data; len = xdp.data_end - xdp.data; @@ -1742,7 +1738,7 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun, err_redirect: put_page(alloc_frag->page); -err_xdp: +out: rcu_read_unlock(); local_bh_enable(); this_cpu_inc(tun->pcpu_stats->rx_dropped); -- 2.17.1