From: baker.zhang <baker.kernel@gmail.com>
Date: Tue, 8 Oct 2013 03:36:51 +0000 (+0800)
Subject: fib_trie: only calc for the un-first node
X-Git-Tag: v3.13-rc1~105^2~199
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4c60f1d67fae632743df9324301e3cb2682f54d4;p=kernel%2Fkernel-generic.git

fib_trie: only calc for the un-first node

This is a enhancement.

for the first node in fib_trie, newpos is 0, bit is 1.
Only for the leaf or node with unmatched key need calc pos.

Signed-off-by: baker.zhang <baker.kernel@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 45c74ba..ec9a9ef 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -1117,12 +1117,8 @@ static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen)
 		 *  first tnode need some special handling
 		 */
 
-		if (tp)
-			pos = tp->pos+tp->bits;
-		else
-			pos = 0;
-
 		if (n) {
+			pos = tp ? tp->pos+tp->bits : 0;
 			newpos = tkey_mismatch(key, pos, n->key);
 			tn = tnode_new(n->key, newpos, 1);
 		} else {