ipvs: reorganize tot_stats

 	The global tot_stats contains cpustats field just like the
stats for dest and svc, so better use it to simplify the usage
in estimation_timer. As tot_stats is registered as estimator
we can remove the special ip_vs_read_cpu_stats call for
tot_stats. Fix ip_vs_read_cpu_stats to be called under
stats lock because it is still used as synchronization between
estimation timer and user context (the stats readers).

 	Also, make sure ip_vs_stats_percpu_show reads properly
the u64 stats from user context.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
diff --git a/net/netfilter/ipvs/ip_vs_est.c b/net/netfilter/ipvs/ip_vs_est.c
index 88bd716..b3751cf 100644
--- a/net/netfilter/ipvs/ip_vs_est.c
+++ b/net/netfilter/ipvs/ip_vs_est.c
@@ -101,13 +101,12 @@
 	struct netns_ipvs *ipvs;
 
 	ipvs = net_ipvs(net);
-	ip_vs_read_cpu_stats(&ipvs->tot_stats->ustats, ipvs->cpustats);
 	spin_lock(&ipvs->est_lock);
 	list_for_each_entry(e, &ipvs->est_list, list) {
 		s = container_of(e, struct ip_vs_stats, est);
 
-		ip_vs_read_cpu_stats(&s->ustats, s->cpustats);
 		spin_lock(&s->lock);
+		ip_vs_read_cpu_stats(&s->ustats, s->cpustats);
 		n_conns = s->ustats.conns;
 		n_inpkts = s->ustats.inpkts;
 		n_outpkts = s->ustats.outpkts;