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, 8 insertions, 4 deletions

diff --git a/arch/ia64/kernel/setup.c b/arch/ia64/kernel/setup.c
index 9e392a30d197..777c8d8bd5e7 100644
--- a/arch/ia64/kernel/setup.c
+++ b/arch/ia64/kernel/setup.c
@@ -528,10 +528,6 @@ setup_arch (char **cmdline_p)
 
 #ifdef CONFIG_SMP
         cpu_physical_id(0) = hard_smp_processor_id();
-
-        cpu_set(0, cpu_sibling_map[0]);
-        cpu_set(0, cpu_core_map[0]);
-
         check_for_logical_procs();
         if (smp_num_cpucores > 1)
                 printk(KERN_INFO
@@ -873,6 +869,14 @@ cpu_init (void)
         void *cpu_data;
 
         cpu_data = per_cpu_init();
+        /*
+         * insert boot cpu into sibling and core mapes
+         * (must be done after per_cpu area is setup)
+         */
+        if (smp_processor_id() == 0) {
+                cpu_set(0, per_cpu(cpu_sibling_map, 0));
+                cpu_set(0, cpu_core_map[0]);
+        }
 
         /*
          * We set ar.k3 so that assembly code in MCA handler can compute