fib: use __fls() on non null argument
__fls(x) is a bit faster than fls(x), granted we know x is non null.
As Ben Hutchings pointed out, fls(x) = __fls(x) + 1
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ben Hutchings <bhutchings@solarflare.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 f0cdb30..f84a0e9 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -1550,7 +1550,8 @@
* state.directly.
*/
if (pref_mismatch) {
- int mp = KEYLENGTH - fls(pref_mismatch);
+ /* fls(x) = __fls(x) + 1 */
+ int mp = KEYLENGTH - __fls(pref_mismatch) - 1;
if (tkey_extract_bits(cn->key, mp, cn->pos - mp) != 0)
goto backtrace;