cpumask: add CPU_MASK_ALL_PTR macro

  * Add a static cpumask_t variable "CPU_MASK_ALL_PTR" to use as
    a pointer reference to CPU_MASK_ALL.  This reduces where possible
    the instances where CPU_MASK_ALL allocates and fills a large
    array on the stack.  Used only if NR_CPUS > BITS_PER_LONG.

  * Change init/main.c to use new set_cpus_allowed_ptr().

Depends on:
	[sched-devel]: sched: add new set_cpus_allowed_ptr function

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/init/main.c b/init/main.c
index 99ce949..2df3f06 100644
--- a/init/main.c
+++ b/init/main.c
@@ -363,6 +363,11 @@
 
 #else
 
+#if NR_CPUS > BITS_PER_LONG
+cpumask_t cpu_mask_all __read_mostly = CPU_MASK_ALL;
+EXPORT_SYMBOL(cpu_mask_all);
+#endif
+
 #ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
 
@@ -811,7 +816,7 @@
 	/*
 	 * init can run on any cpu.
 	 */
-	set_cpus_allowed(current, CPU_MASK_ALL);
+	set_cpus_allowed_ptr(current, CPU_MASK_ALL_PTR);
 	/*
 	 * Tell the world that we're going to be the grim
 	 * reaper of innocent orphaned children.