[NET]: Wider use of for_each_*cpu()

In 'net' change the explicit use of for-loops and NR_CPUS into the
general for_each_cpu() or for_each_online_cpu() constructs, as
appropriate.  This widens the scope of potential future optimizations
of the general constructs, as well as takes advantage of the existing
optimizations of first_cpu() and next_cpu(), which is advantageous
when the true CPU count is much smaller than NR_CPUS.

Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

net/core/neighbour.c

@@ -1625,12 +1625,9 @@ static int neightbl_fill_info(struct neigh_table *tbl, struct sk_buff *skb,
 
 		memset(&ndst, 0, sizeof(ndst));
 
-		for (cpu = 0; cpu < NR_CPUS; cpu++) {
+		for_each_cpu(cpu) {
 			struct neigh_statistics	*st;
 
-			if (!cpu_possible(cpu))
-				continue;
-
 			st = per_cpu_ptr(tbl->stats, cpu);
 			ndst.ndts_allocs		+= st->allocs;
 			ndst.ndts_destroys		+= st->destroys;

net/core/pktgen.c

@@ -3065,12 +3065,9 @@ static int __init pg_init(void)
 	/* Register us to receive netdevice events */
 	register_netdevice_notifier(&pktgen_notifier_block);
 
-	for (cpu = 0; cpu < NR_CPUS ; cpu++) {
+	for_each_online_cpu(cpu) {
 		char buf[30];
 
-		if (!cpu_online(cpu))
-			continue;
-
                 sprintf(buf, "kpktgend_%i", cpu);
                 pktgen_create_thread(buf, cpu);
         }

net/ipv4/icmp.c

@@ -1108,12 +1108,9 @@ void __init icmp_init(struct net_proto_family *ops)
 	struct inet_sock *inet;
 	int i;
 
-	for (i = 0; i < NR_CPUS; i++) {
+	for_each_cpu(i) {
 		int err;
 
-		if (!cpu_possible(i))
-			continue;
-
 		err = sock_create_kern(PF_INET, SOCK_RAW, IPPROTO_ICMP,
 				       &per_cpu(__icmp_socket, i));
 

net/ipv4/proc.c

@@ -90,9 +90,7 @@ fold_field(void *mib[], int offt)
 	unsigned long res = 0;
 	int i;
 
-	for (i = 0; i < NR_CPUS; i++) {
-		if (!cpu_possible(i))
-			continue;
+	for_each_cpu(i) {
 		res += *(((unsigned long *) per_cpu_ptr(mib[0], i)) + offt);
 		res += *(((unsigned long *) per_cpu_ptr(mib[1], i)) + offt);
 	}

net/ipv6/icmp.c

@@ -700,10 +700,7 @@ int __init icmpv6_init(struct net_proto_family *ops)
 	struct sock *sk;
 	int err, i, j;
 
-	for (i = 0; i < NR_CPUS; i++) {
-		if (!cpu_possible(i))
-			continue;
-
+	for_each_cpu(i) {
 		err = sock_create_kern(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6,
 				       &per_cpu(__icmpv6_socket, i));
 		if (err < 0) {
@@ -749,9 +746,7 @@ void icmpv6_cleanup(void)
 {
 	int i;
 
-	for (i = 0; i < NR_CPUS; i++) {
-		if (!cpu_possible(i))
-			continue;
+	for_each_cpu(i) {
 		sock_release(per_cpu(__icmpv6_socket, i));
 	}
 	inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);

net/ipv6/proc.c

@@ -140,9 +140,7 @@ fold_field(void *mib[], int offt)
         unsigned long res = 0;
         int i;
 
-        for (i = 0; i < NR_CPUS; i++) {
-                if (!cpu_possible(i))
-                        continue;
+        for_each_cpu(i) {
                 res += *(((unsigned long *)per_cpu_ptr(mib[0], i)) + offt);
                 res += *(((unsigned long *)per_cpu_ptr(mib[1], i)) + offt);
         }

net/sctp/proc.c

@@ -69,9 +69,7 @@ fold_field(void *mib[], int nr)
 	unsigned long res = 0;
 	int i;
 
-	for (i = 0; i < NR_CPUS; i++) {
-		if (!cpu_possible(i))
-			continue;
+	for_each_cpu(i) {
 		res +=
 		    *((unsigned long *) (((void *) per_cpu_ptr(mib[0], i)) +
 					 sizeof (unsigned long) * nr));