[PATCH net-next] net: ipv4: optimize tkey_mismatch
From: <hidden>
Date: 2012-08-28 08:53:11
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
From: Igor Maravic <redacted> Optimize tkey_mismatch function by using __fls function. Signed-off-by: Igor Maravic <redacted> --- net/ipv4/fib_trie.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-)
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index ec45621..b4b126c 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c@@ -265,14 +265,8 @@ static inline int tkey_sub_equals(t_key a, int offset, int bits, t_key b) static inline int tkey_mismatch(t_key a, int offset, t_key b) { - t_key diff = a ^ b; - int i = offset; - - if (!diff) - return 0; - while ((diff << i) >> (KEYLENGTH-1) == 0) - i++; - return i; + t_key diff = (a ^ b) & (~((t_key)0) << offset >> offset); + return diff ? (KEYLENGTH - __fls(diff) - 1) : 0; } /*
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1.7.9.5