From: Eric Dumazet Date: Fri, 21 Dec 2007 09:49:07 +0000 (-0800) Subject: [INET]: Avoid an integer divide in rt_garbage_collect() X-Git-Tag: v2.6.25-rc1~1162^2~929 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b790cedd24a7f7d1639072b3faf35f1f56cb38ea;p=linux-2.6 [INET]: Avoid an integer divide in rt_garbage_collect() Since 'goal' is a signed int, compiler may emit an integer divide to compute goal/2. Using a right shift is OK here and less expensive. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 1cc6c23cf7..933b093721 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -851,14 +851,14 @@ static int rt_garbage_collect(void) equilibrium = ipv4_dst_ops.gc_thresh; goal = atomic_read(&ipv4_dst_ops.entries) - equilibrium; if (goal > 0) { - equilibrium += min_t(unsigned int, goal / 2, rt_hash_mask + 1); + equilibrium += min_t(unsigned int, goal >> 1, rt_hash_mask + 1); goal = atomic_read(&ipv4_dst_ops.entries) - equilibrium; } } else { /* We are in dangerous area. Try to reduce cache really * aggressively. */ - goal = max_t(unsigned int, goal / 2, rt_hash_mask + 1); + goal = max_t(unsigned int, goal >> 1, rt_hash_mask + 1); equilibrium = atomic_read(&ipv4_dst_ops.entries) - goal; }