From patchwork Wed May 2 06:22:39 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Horman X-Patchwork-Id: 156357 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 3DC59B6F62 for ; Wed, 2 May 2012 16:23:58 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756232Ab2EBGXG (ORCPT ); Wed, 2 May 2012 02:23:06 -0400 Received: from kirsty.vergenet.net ([202.4.237.240]:44698 "EHLO kirsty.vergenet.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755611Ab2EBGWu (ORCPT ); Wed, 2 May 2012 02:22:50 -0400 Received: from ayumi.akashicho.tokyo.vergenet.net (p5238-ipbfp903kobeminato.hyogo.ocn.ne.jp [123.221.44.238]) by kirsty.vergenet.net (Postfix) with ESMTP id 0C828267164; Wed, 2 May 2012 16:22:49 +1000 (EST) Received: by ayumi.akashicho.tokyo.vergenet.net (Postfix, from userid 7100) id 1ABC6EDE57F; Wed, 2 May 2012 15:22:46 +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 , Hans Schillstrom , Jesper Dangaard Brouer , Simon Horman Subject: [PATCH 15/18] ipvs: optimize the use of flags in ip_vs_bind_dest Date: Wed, 2 May 2012 15:22:39 +0900 Message-Id: <1335939762-1912-16-git-send-email-horms@verge.net.au> X-Mailer: git-send-email 1.7.10 In-Reply-To: <1335939762-1912-1-git-send-email-horms@verge.net.au> References: <1335939762-1912-1-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 file changed, 9 insertions(+), 6 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c index 6a43c93..7f21b91 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);