From cf8da764fc6959b7efb482f375dfef9830e98205 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 19 May 2009 18:54:22 +0000 Subject: [PATCH] net: fix length computation in rt_check_expire() rt_check_expire() computes average and standard deviation of chain lengths, but not correclty reset length to 0 at beginning of each chain. This probably gives overflows for sum2 (and sum) on loaded machines instead of meaningful results. Signed-off-by: Eric Dumazet Acked-by: Neil Horman Signed-off-by: David S. Miller --- net/ipv4/route.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/ipv4/route.c b/net/ipv4/route.c index c4c60e9..869cf1c 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -785,7 +785,7 @@ static void rt_check_expire(void) static unsigned int rover; unsigned int i = rover, goal; struct rtable *rth, **rthp; - unsigned long length = 0, samples = 0; + unsigned long samples = 0; unsigned long sum = 0, sum2 = 0; u64 mult; @@ -795,9 +795,9 @@ static void rt_check_expire(void) goal = (unsigned int)mult; if (goal > rt_hash_mask) goal = rt_hash_mask + 1; - length = 0; for (; goal > 0; goal--) { unsigned long tmo = ip_rt_gc_timeout; + unsigned long length; i = (i + 1) & rt_hash_mask; rthp = &rt_hash_table[i].chain; @@ -809,6 +809,7 @@ static void rt_check_expire(void) if (*rthp == NULL) continue; + length = 0; spin_lock_bh(rt_hash_lock_addr(i)); while ((rth = *rthp) != NULL) { if (rt_is_expired(rth)) { -- 2.7.4