[INET]: Consolidate the xxx_evictor

The evictors collect some statistics for ipv4 and ipv6,
so make it return the number of evicted queues and account
them all at once in the caller.

The XXX_ADD_STATS_BH() macros are just for this case,
but maybe there are places in code, that can make use of
them as well.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/ip.h b/include/net/ip.h
index e6aa955..840dd91 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -160,6 +160,7 @@
 #define IP_INC_STATS(field)		SNMP_INC_STATS(ip_statistics, field)
 #define IP_INC_STATS_BH(field)		SNMP_INC_STATS_BH(ip_statistics, field)
 #define IP_INC_STATS_USER(field) 	SNMP_INC_STATS_USER(ip_statistics, field)
+#define IP_ADD_STATS_BH(field, val)	SNMP_ADD_STATS_BH(ip_statistics, field, val)
 DECLARE_SNMP_STAT(struct linux_mib, net_statistics);
 #define NET_INC_STATS(field)		SNMP_INC_STATS(net_statistics, field)
 #define NET_INC_STATS_BH(field)		SNMP_INC_STATS_BH(net_statistics, field)