nommu: struct vm_region's vm_usage count need not be atomic

The vm_usage count field in struct vm_region does not need to be atomic as
it's only even modified whilst nommu_region_sem is write locked.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 84d020bed083..80cfa78a8cf6 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -122,7 +122,7 @@ struct vm_region {
         unsigned long   vm_pgoff;       /* the offset in vm_file corresponding to vm_start */
         struct file     *vm_file;       /* the backing file or NULL */
 
-        atomic_t        vm_usage;       /* region usage count */
+        int             vm_usage;       /* region usage count (access under nommu_region_sem) */
         bool            vm_icache_flushed : 1; /* true if the icache has been flushed for
                                                 * this region */
 };