From patchwork Thu Oct 31 11:47:06 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 287461 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 4E2DD2C03D5 for ; Thu, 31 Oct 2013 22:47:59 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751899Ab3JaLr1 (ORCPT ); Thu, 31 Oct 2013 07:47:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:30269 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751381Ab3JaLr1 (ORCPT ); Thu, 31 Oct 2013 07:47:27 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r9VBlJO5013137 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 31 Oct 2013 07:47:19 -0400 Received: from jason-ThinkPad-T430s.redhat.com (dhcp-66-71-71.eng.nay.redhat.com [10.66.71.71] (may be forged)) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id r9VBlFro023775; Thu, 31 Oct 2013 07:47:16 -0400 From: Jason Wang To: davem@davemloft.net, edumazet@google.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, rusty@rustcorp.com.au, mst@redhat.com, mwdalton@google.com, virtualization@lists.linux-foundation.org Cc: kmindg@gmail.com, Jason Wang Subject: [PATCH net-next V2 1/2] net: introduce skb_coalesce_rx_frag() Date: Thu, 31 Oct 2013 19:47:06 +0800 Message-Id: <1383220027-12278-1-git-send-email-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Sometimes we need to coalesce the rx frags to avoid frag list. One example is virtio-net driver which tries to use small frags for both MTU sized packet and GSO packet. So this patch introduce skb_coalesce_rx_frag() to do this. Cc: Rusty Russell Cc: Michael S. Tsirkin Cc: Michael Dalton Cc: Eric Dumazet Acked-by: Michael S. Tsirkin Signed-off-by: Jason Wang --- Changes from V1: - remove the useless off parameter. --- include/linux/skbuff.h | 3 +++ net/core/skbuff.c | 13 +++++++++++++ 2 files changed, 16 insertions(+) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 2c15497..fffaeaf 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1372,6 +1372,9 @@ static inline void skb_fill_page_desc(struct sk_buff *skb, int i, void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off, int size, unsigned int truesize); +void skb_coalesce_rx_frag(struct sk_buff *skb, int i, int size, + unsigned int truesize); + #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags) #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_has_frag_list(skb)) #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb)) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 0ab32fa..87670e1 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -476,6 +476,19 @@ void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off, } EXPORT_SYMBOL(skb_add_rx_frag); +void skb_coalesce_rx_frag(struct sk_buff *skb, int i, int size, + unsigned int truesize) +{ + skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + + skb_frag_size_add(frag, size); + skb->len += size; + skb->data_len += size; + skb->truesize += truesize; + skb_frag_unref(skb, i); +} +EXPORT_SYMBOL(skb_coalesce_rx_frag); + static void skb_drop_list(struct sk_buff **listp) { kfree_skb_list(*listp);