cpumask: put cpumask_of_cpu_map in the initdata section

  * Create the cpumask_of_cpu_map statically in the init data section
    using NR_CPUS but replace it during boot up with one sized by
    nr_cpu_ids (num possible cpus).

Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 11 insertions, 7 deletions

diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c
index f7745f94c006..1cd53dfcd309 100644
--- a/arch/x86/kernel/setup_percpu.c
+++ b/arch/x86/kernel/setup_percpu.c
@@ -81,10 +81,12 @@ static void __init setup_per_cpu_maps(void)
 }
 
 #ifdef CONFIG_HAVE_CPUMASK_OF_CPU_MAP
-cpumask_t *cpumask_of_cpu_map __read_mostly;
-EXPORT_SYMBOL(cpumask_of_cpu_map);
-
-/* requires nr_cpu_ids to be initialized */
+/*
+ * Replace static cpumask_of_cpu_map in the initdata section,
+ * with one that's allocated sized by the possible number of cpus.
+ *
+ * (requires nr_cpu_ids to be initialized)
+ */
 static void __init setup_cpumask_of_cpu(void)
 {
         int i;
diff --git a/kernel/cpu.c b/kernel/cpu.c
index fe31ff3d3809..9d4e1c28c053 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -462,7 +462,6 @@ out:
 
 #endif /* CONFIG_SMP */
 
-#ifndef CONFIG_HAVE_CPUMASK_OF_CPU_MAP
 /* 64 bits of zeros, for initializers. */
 #if BITS_PER_LONG == 32
 #define Z64 0, 0
@@ -509,7 +508,11 @@ out:
 
 /* We want this statically initialized, just to be safe.  We try not
  * to waste too much space, either. */
-static const cpumask_t cpumask_map[] = {
+static const cpumask_t cpumask_map[]
+#ifdef CONFIG_HAVE_CPUMASK_OF_CPU_MAP
+__initdata
+#endif
+= {
         CMI0(0), CMI0(1), CMI0(2), CMI0(3),
 #if NR_CPUS > 4
         CMI0(4), CMI0(5), CMI0(6), CMI0(7),
@@ -569,4 +572,3 @@ static const cpumask_t cpumask_map[] = {
 };
 
 const cpumask_t *cpumask_of_cpu_map = cpumask_map;
-#endif /* !CONFIG_HAVE_CPUMASK_OF_CPU_MAP */