ipvs: optimize rates reading

 	Move the estimator reading from estimation_timer to user
context. ip_vs_read_estimator() will be used to decode the rate
values. As the decoded rates are not set by estimation timer
there is no need to reset them in ip_vs_zero_stats.

 	There is no need ip_vs_new_estimator() to encode stats
to rates, if the destination is in trash both the stats and the
rates are inactive.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index cf014ab..e4a39c4 100644
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -1179,6 +1179,8 @@
 extern void ip_vs_new_estimator(struct net *net, struct ip_vs_stats *stats);
 extern void ip_vs_kill_estimator(struct net *net, struct ip_vs_stats *stats);
 extern void ip_vs_zero_estimator(struct ip_vs_stats *stats);
+extern void ip_vs_read_estimator(struct ip_vs_stats_user *dst,
+				 struct ip_vs_stats *stats);
 
 /*
  *	Various IPVS packet transmitters (from ip_vs_xmit.c)