mm/mmap.c: remove redundant local variables for may_expand_vm()

Simplify may_expand_vm().

[akpm@linux-foundation.org: further simplification, per Naoya Horiguchi]
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/mmap.c

@@ -2988,14 +2988,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
  */
 int may_expand_vm(struct mm_struct *mm, unsigned long npages)
 {
-	unsigned long cur = mm->total_vm;	/* pages */
-	unsigned long lim;
-
-	lim = rlimit(RLIMIT_AS) >> PAGE_SHIFT;
-
-	if (cur + npages > lim)
-		return 0;
-	return 1;
+	return mm->total_vm + npages <= rlimit(RLIMIT_AS) >> PAGE_SHIFT;
 }
 
 static int special_mapping_fault(struct vm_area_struct *vma,