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 <dada1@cosmosbay.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 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 @@
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 @@
if (*rthp == NULL)
continue;
+ length = 0;
spin_lock_bh(rt_hash_lock_addr(i));
while ((rth = *rthp) != NULL) {
if (rt_is_expired(rth)) {