[NET]: use __read_mostly on kmem_cache_t , DEFINE_SNMP_STAT pointers
This patch puts mostly read only data in the right section
(read_mostly), to help sharing of these data between CPUS without
memory ping pongs.
On one of my production machine, tcp_statistics was sitting in a
heavily modified cache line, so *every* SNMP update had to force a
reload.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/flow.c b/net/core/flow.c
index f289570..7e95b39 100644
--- a/net/core/flow.c
+++ b/net/core/flow.c
@@ -42,7 +42,7 @@
#define flow_table(cpu) (per_cpu(flow_tables, cpu))
-static kmem_cache_t *flow_cachep;
+static kmem_cache_t *flow_cachep __read_mostly;
static int flow_lwm, flow_hwm;