[PATCH] percpu data: only iterate over possible CPUs

percpu_data blindly allocates bootmem memory to store NR_CPUS instances of
cpudata, instead of allocating memory only for possible cpus.

As a preparation for changing that, we need to convert various 0 -> NR_CPUS
loops to use for_each_cpu().

(The above only applies to users of asm-generic/percpu.h.  powerpc has gone it
alone and is presently only allocating memory for present CPUs, so it's
currently corrupting memory).

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Jens Axboe <axboe@suse.de>
Cc: Anton Blanchard <anton@samba.org>
Acked-by: William Irwin <wli@holomorphy.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/net/core/dev.c b/net/core/dev.c
index ffb8207..2afb0de 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3237,7 +3237,7 @@
 	 *	Initialise the packet receive queues.
 	 */
 
-	for (i = 0; i < NR_CPUS; i++) {
+	for_each_cpu(i) {
 		struct softnet_data *queue;
 
 		queue = &per_cpu(softnet_data, i);
diff --git a/net/core/utils.c b/net/core/utils.c
index ac1d1fc..fdc4f38 100644
--- a/net/core/utils.c
+++ b/net/core/utils.c
@@ -121,7 +121,7 @@
 {
 	int i;
 
-	for (i = 0; i < NR_CPUS; i++) {
+	for_each_cpu(i) {
 		struct nrnd_state *state = &per_cpu(net_rand_state,i);
 		__net_srandom(state, i+jiffies);
 	}
@@ -133,7 +133,7 @@
 	unsigned long seed[NR_CPUS];
 
 	get_random_bytes(seed, sizeof(seed));
-	for (i = 0; i < NR_CPUS; i++) {
+	for_each_cpu(i) {
 		struct nrnd_state *state = &per_cpu(net_rand_state,i);
 		__net_srandom(state, seed[i]);
 	}
diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c
index 39d49dc..1b167c4b 100644
--- a/net/ipv4/proc.c
+++ b/net/ipv4/proc.c
@@ -49,7 +49,7 @@
 	int res = 0;
 	int cpu;
 
-	for (cpu = 0; cpu < NR_CPUS; cpu++)
+	for_each_cpu(cpu)
 		res += proto->stats[cpu].inuse;
 
 	return res;
diff --git a/net/ipv6/proc.c b/net/ipv6/proc.c
index 50a13e7..4238b1e 100644
--- a/net/ipv6/proc.c
+++ b/net/ipv6/proc.c
@@ -38,7 +38,7 @@
 	int res = 0;
 	int cpu;
 
-	for (cpu=0; cpu<NR_CPUS; cpu++)
+	for_each_cpu(cpu)
 		res += proto->stats[cpu].inuse;
 
 	return res;
diff --git a/net/socket.c b/net/socket.c
index b38a263..a00851f 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -2078,7 +2078,7 @@
 	int cpu;
 	int counter = 0;
 
-	for (cpu = 0; cpu < NR_CPUS; cpu++)
+	for_each_cpu(cpu)
 		counter += per_cpu(sockets_in_use, cpu);
 
 	/* It can be negative, by the way. 8) */