xfrm: use new function dev_fetch_sw_netstats

Simplify the code by using new function dev_fetch_sw_netstats().
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/a6b816f4-bbf2-9db0-d59a-7e4e9cc808fe@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

net/xfrm/xfrm_interface.c

@@ -541,27 +541,7 @@ static int xfrmi_update(struct xfrm_if *xi, struct xfrm_if_parms *p)
 static void xfrmi_get_stats64(struct net_device *dev,
 			       struct rtnl_link_stats64 *s)
 {
-	int cpu;
-
-	for_each_possible_cpu(cpu) {
-		struct pcpu_sw_netstats *stats;
-		struct pcpu_sw_netstats tmp;
-		int start;
-
-		stats = per_cpu_ptr(dev->tstats, cpu);
-		do {
-			start = u64_stats_fetch_begin_irq(&stats->syncp);
-			tmp.rx_packets = stats->rx_packets;
-			tmp.rx_bytes   = stats->rx_bytes;
-			tmp.tx_packets = stats->tx_packets;
-			tmp.tx_bytes   = stats->tx_bytes;
-		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
-
-		s->rx_packets += tmp.rx_packets;
-		s->rx_bytes   += tmp.rx_bytes;
-		s->tx_packets += tmp.tx_packets;
-		s->tx_bytes   += tmp.tx_bytes;
-	}
+	dev_fetch_sw_netstats(s, dev->tstats);
 
 	s->rx_dropped = dev->stats.rx_dropped;
 	s->tx_dropped = dev->stats.tx_dropped;