mm: convert mm->cpu_vm_cpumask into cpumask_var_t

cpumask_t is very big struct and cpu_vm_mask is placed wrong position.
It might lead to reduce cache hit ratio.

This patch has two change.
1) Move the place of cpumask into last of mm_struct. Because usually cpumask
   is accessed only front bits when the system has cpu-hotplug capability
2) Convert cpu_vm_mask into cpumask_var_t. It may help to reduce memory
   footprint if cpumask_size() will use nr_cpumask_bits properly in future.

In addition, this patch change the name of cpu_vm_mask with cpu_vm_mask_var.
It may help to detect out of tree cpu_vm_mask users.

This patch has no functional change.

[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 0 insertions, 1 deletions

diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index 998e972f3b1a..30ac65df7d4e 100644
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -110,7 +110,6 @@ static struct mm_struct tboot_mm = {
         .mmap_sem       = __RWSEM_INITIALIZER(init_mm.mmap_sem),
         .page_table_lock =  __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock),
         .mmlist         = LIST_HEAD_INIT(init_mm.mmlist),
-        .cpu_vm_mask    = CPU_MASK_ALL,
 };
 
 static inline void switch_to_tboot_pt(void)