[PATCH V2 net-next] fib_trie: avoid a redundant bit judgement in inflate

[PATCH V2 net-next] fib_trie: avoid a redundant bit judgement in inflate

[baker.kernel]

From: "baker.zhang" <baker.kernel@gmail.com>

Because 'node' is the i'st child of 'oldnode',
thus, here 'i' equals
tkey_extract_bits(node->key, oldtnode->pos, oldtnode->bits)

we just get 1 more bit,
and need not care the detail value of this bits.

Signed-off-by: baker.zhang <baker.kernel@gmail.com>
---
 net/ipv4/fib_trie.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 3df6d3e..45c74ba 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -762,12 +762,9 @@ static struct tnode *inflate(struct trie *t, struct tnode *tn)
 
 		if (IS_LEAF(node) || ((struct tnode *) node)->pos >
 		   tn->pos + tn->bits - 1) {
-			if (tkey_extract_bits(node->key,
-					      oldtnode->pos + oldtnode->bits,
-					      1) == 0)
-				put_child(tn, 2*i, node);
-			else
-				put_child(tn, 2*i+1, node);
+			put_child(tn,
+				tkey_extract_bits(node->key, oldtnode->pos, oldtnode->bits + 1),
+				node);
 			continue;
 		}
 
-- 
1.8.1.2

Re: [PATCH V2 net-next] fib_trie: avoid a redundant bit judgement in inflate

[David Miller]

Based upon how quickly you sent these two patches, the first of which
wouldn't even compile, I have zero confidence that you actually
booted and tested this patch at all.

I'm not applying this until you take the time to boot and test the
change in some way, and say explicitly in your commit message how
you tested it.