From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next-2.6] net: eth_type_trans() should inline skb_pull() Date: Sat, 01 May 2010 18:15:58 -0700 (PDT) Message-ID: <20100501.181558.141243424.davem@davemloft.net> References: <1272696145.2230.101.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, therbert@google.com, hadi@cyberus.ca To: eric.dumazet@gmail.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:49759 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753648Ab0EBBPy (ORCPT ); Sat, 1 May 2010 21:15:54 -0400 In-Reply-To: <1272696145.2230.101.camel@edumazet-laptop> Sender: netdev-owner@vger.kernel.org List-ID: From: Eric Dumazet Date: Sat, 01 May 2010 08:42:25 +0200 > [PATCH net-next-2.6] net: eth_type_trans() should inline skb_pull() > > With RPS, this patch can give a 5 % boost in performance. > > Signed-off-by: Eric Dumazet Awesome, but let's do this in a way that allows us to easily annotate where inlining makes sense in other places, not just here. Something like this, ok? diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 82f5116..746a652 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1128,6 +1128,11 @@ static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len) return skb->data += len; } +static inline unsigned char *skb_pull_inline(struct sk_buff *skb, unsigned int len) +{ + return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len); +} + extern unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta); static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 4218ff4..8b9c109 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1051,7 +1051,7 @@ EXPORT_SYMBOL(skb_push); */ unsigned char *skb_pull(struct sk_buff *skb, unsigned int len) { - return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len); + return skb_pull_inline(skb, len); } EXPORT_SYMBOL(skb_pull); diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c index 0c0d272..61ec032 100644 --- a/net/ethernet/eth.c +++ b/net/ethernet/eth.c @@ -162,7 +162,7 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev) skb->dev = dev; skb_reset_mac_header(skb); - skb_pull(skb, ETH_HLEN); + skb_pull_inline(skb, ETH_HLEN); eth = eth_hdr(skb); if (unlikely(is_multicast_ether_addr(eth->h_dest))) {