Convert cpu_sibling_map to be a per cpu variable

Convert cpu_sibling_map from a static array sized by NR_CPUS to a per_cpu
variable.  This saves sizeof(cpumask_t) * NR unused cpus.  Access is mostly
from startup and CPU HOTPLUG functions.

Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 4 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index bba57adb9504..78c8fbd373a3 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -5869,7 +5869,7 @@ static int cpu_to_core_group(int cpu, const cpumask_t *cpu_map,
                              struct sched_group **sg)
 {
         int group;
-        cpumask_t mask = cpu_sibling_map[cpu];
+        cpumask_t mask = per_cpu(cpu_sibling_map, cpu);
         cpus_and(mask, mask, *cpu_map);
         group = first_cpu(mask);
         if (sg)
@@ -5898,7 +5898,7 @@ static int cpu_to_phys_group(int cpu, const cpumask_t *cpu_map,
         cpus_and(mask, mask, *cpu_map);
         group = first_cpu(mask);
 #elif defined(CONFIG_SCHED_SMT)
-        cpumask_t mask = cpu_sibling_map[cpu];
+        cpumask_t mask = per_cpu(cpu_sibling_map, cpu);
         cpus_and(mask, mask, *cpu_map);
         group = first_cpu(mask);
 #else
@@ -6132,7 +6132,7 @@ static int build_sched_domains(const cpumask_t *cpu_map)
                 p = sd;
                 sd = &per_cpu(cpu_domains, i);
                 *sd = SD_SIBLING_INIT;
-                sd->span = cpu_sibling_map[i];
+                sd->span = per_cpu(cpu_sibling_map, i);
                 cpus_and(sd->span, sd->span, *cpu_map);
                 sd->parent = p;
                 p->child = sd;
@@ -6143,7 +6143,7 @@ static int build_sched_domains(const cpumask_t *cpu_map)
 #ifdef CONFIG_SCHED_SMT
         /* Set up CPU (sibling) groups */
         for_each_cpu_mask(i, *cpu_map) {
-                cpumask_t this_sibling_map = cpu_sibling_map[i];
+                cpumask_t this_sibling_map = per_cpu(cpu_sibling_map, i);
                 cpus_and(this_sibling_map, this_sibling_map, *cpu_map);
                 if (i != first_cpu(this_sibling_map))
                         continue;