memcg: move charges to root cgroup if use_hierarchy=0

[karo-tx-linux.git] / mm / mmap.c

diff --git a/mm/mmap.c b/mm/mmap.c
index e8dcfc7de866e2b7c1a1dccd90eb4a9aff89161d..4a9c2a391e28efe523e1a3aaaf9ab06d24627e86 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1639,33 +1639,34 @@ struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
 {
        struct vm_area_struct *vma = NULL;
 
-       if (mm) {
-               /* Check the cache first. */
-               /* (Cache hit rate is typically around 35%.) */
-               vma = mm->mmap_cache;
-               if (!(vma && vma->vm_end > addr && vma->vm_start <= addr)) {
-                       struct rb_node * rb_node;
-
-                       rb_node = mm->mm_rb.rb_node;
-                       vma = NULL;
-
-                       while (rb_node) {
-                               struct vm_area_struct * vma_tmp;
-
-                               vma_tmp = rb_entry(rb_node,
-                                               struct vm_area_struct, vm_rb);
-
-                               if (vma_tmp->vm_end > addr) {
-                                       vma = vma_tmp;
-                                       if (vma_tmp->vm_start <= addr)
-                                               break;
-                                       rb_node = rb_node->rb_left;
-                               } else
-                                       rb_node = rb_node->rb_right;
-                       }
-                       if (vma)
-                               mm->mmap_cache = vma;
+       if (WARN_ON_ONCE(!mm))          /* Remove this in linux-3.6 */
+               return NULL;
+
+       /* Check the cache first. */
+       /* (Cache hit rate is typically around 35%.) */
+       vma = mm->mmap_cache;
+       if (!(vma && vma->vm_end > addr && vma->vm_start <= addr)) {
+               struct rb_node *rb_node;
+
+               rb_node = mm->mm_rb.rb_node;
+               vma = NULL;
+
+               while (rb_node) {
+                       struct vm_area_struct *vma_tmp;
+
+                       vma_tmp = rb_entry(rb_node,
+                                          struct vm_area_struct, vm_rb);
+
+                       if (vma_tmp->vm_end > addr) {
+                               vma = vma_tmp;
+                               if (vma_tmp->vm_start <= addr)
+                                       break;
+                               rb_node = rb_node->rb_left;
+                       } else
+                               rb_node = rb_node->rb_right;
                }
+               if (vma)
+                       mm->mmap_cache = vma;
        }
        return vma;
 }