From patchwork Wed Mar 21 08:56:23 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Horman X-Patchwork-Id: 147941 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44334B6F13 for ; Wed, 21 Mar 2012 19:57:11 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932069Ab2CUI5B (ORCPT ); Wed, 21 Mar 2012 04:57:01 -0400 Received: from kirsty.vergenet.net ([202.4.237.240]:56369 "EHLO kirsty.vergenet.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756697Ab2CUI4e (ORCPT ); Wed, 21 Mar 2012 04:56:34 -0400 Received: from joe.kanocho.kobe.vergenet.net (joe.isobedori.kobe.vergenet.net [IPv6:2001:470:4832:303:1ec1:deff:fe98:754d]) by kirsty.vergenet.net (Postfix) with ESMTP id 2FED025BF69; Wed, 21 Mar 2012 19:56:29 +1100 (EST) Received: by joe.kanocho.kobe.vergenet.net (Postfix, from userid 7100) id 524FC28A04C; Wed, 21 Mar 2012 17:56:27 +0900 (JST) From: Simon Horman To: Pablo Neira Ayuso Cc: lvs-devel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, Wensong Zhang , Julian Anastasov , Simon Horman Subject: [PATCH 8/9] ipvs: optimize the use of flags in ip_vs_bind_dest Date: Wed, 21 Mar 2012 17:56:23 +0900 Message-Id: <1332320185-27157-9-git-send-email-horms@verge.net.au> X-Mailer: git-send-email 1.7.6.3 In-Reply-To: <1332320185-27157-1-git-send-email-horms@verge.net.au> References: <1332320185-27157-1-git-send-email-horms@verge.net.au> Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org From: Julian Anastasov cp->flags is marked volatile but ip_vs_bind_dest can safely modify the flags, so save some CPU cycles by using temp variable. Signed-off-by: Julian Anastasov Signed-off-by: Simon Horman --- net/netfilter/ipvs/ip_vs_conn.c | 15 +++++++++------ 1 files changed, 9 insertions(+), 6 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c index 7478b66..1eaec99 100644 --- a/net/netfilter/ipvs/ip_vs_conn.c +++ b/net/netfilter/ipvs/ip_vs_conn.c @@ -548,6 +548,7 @@ static inline void ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest) { unsigned int conn_flags; + __u32 flags; /* if dest is NULL, then return directly */ if (!dest) @@ -559,17 +560,19 @@ ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest) conn_flags = atomic_read(&dest->conn_flags); if (cp->protocol != IPPROTO_UDP) conn_flags &= ~IP_VS_CONN_F_ONE_PACKET; + flags = cp->flags; /* Bind with the destination and its corresponding transmitter */ - if (cp->flags & IP_VS_CONN_F_SYNC) { + if (flags & IP_VS_CONN_F_SYNC) { /* if the connection is not template and is created * by sync, preserve the activity flag. */ - if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) + if (!(flags & IP_VS_CONN_F_TEMPLATE)) conn_flags &= ~IP_VS_CONN_F_INACTIVE; /* connections inherit forwarding method from dest */ - cp->flags &= ~(IP_VS_CONN_F_FWD_MASK | IP_VS_CONN_F_NOOUTPUT); + flags &= ~(IP_VS_CONN_F_FWD_MASK | IP_VS_CONN_F_NOOUTPUT); } - cp->flags |= conn_flags; + flags |= conn_flags; + cp->flags = flags; cp->dest = dest; IP_VS_DBG_BUF(7, "Bind-dest %s c:%s:%d v:%s:%d " @@ -584,11 +587,11 @@ ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest) atomic_read(&dest->refcnt)); /* Update the connection counters */ - if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) { + if (!(flags & IP_VS_CONN_F_TEMPLATE)) { /* It is a normal connection, so modify the counters * according to the flags, later the protocol can * update them on state change */ - if (!(cp->flags & IP_VS_CONN_F_INACTIVE)) + if (!(flags & IP_VS_CONN_F_INACTIVE)) atomic_inc(&dest->activeconns); else atomic_inc(&dest->inactconns);