net: use this_cpu_ptr()

use this_cpu_ptr(p) instead of per_cpu_ptr(p, smp_processor_id())

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index db47a5a..d859bcc 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -342,7 +342,7 @@
 
 #ifdef CONFIG_NET_CLS_ROUTE
 	if (unlikely(skb_dst(skb)->tclassid)) {
-		struct ip_rt_acct *st = per_cpu_ptr(ip_rt_acct, smp_processor_id());
+		struct ip_rt_acct *st = this_cpu_ptr(ip_rt_acct);
 		u32 idx = skb_dst(skb)->tclassid;
 		st[idx&0xFF].o_packets++;
 		st[idx&0xFF].o_bytes += skb->len;