mm: add CONFIG_DEBUG_VM_RB build option

[firefly-linux-kernel-4.4.55.git] / mm / mmap.c

diff --git a/mm/mmap.c b/mm/mmap.c
index 2e580ed7921176b694db73693d185f0922f9926f..deb422c39e21590ab680ea0142c02d42c24d95b0 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -51,12 +51,6 @@ static void unmap_region(struct mm_struct *mm,
                struct vm_area_struct *vma, struct vm_area_struct *prev,
                unsigned long start, unsigned long end);
 
-/*
- * WARNING: the debugging will use recursive algorithms so never enable this
- * unless you know what you are doing.
- */
-#undef DEBUG_MM_RB
-
 /* description of effects of mapping type and prot in current implementation.
  * this is due to the limited x86 page protection hardware.  The expected
  * behavior is in parens:
@@ -303,7 +297,7 @@ out:
        return retval;
 }
 
-#ifdef DEBUG_MM_RB
+#ifdef CONFIG_DEBUG_VM_RB
 static int browse_rb(struct rb_root *root)
 {
        int i = 0, j;
@@ -337,9 +331,12 @@ void validate_mm(struct mm_struct *mm)
 {
        int bug = 0;
        int i = 0;
-       struct vm_area_struct *tmp = mm->mmap;
-       while (tmp) {
-               tmp = tmp->vm_next;
+       struct vm_area_struct *vma = mm->mmap;
+       while (vma) {
+               struct anon_vma_chain *avc;
+               list_for_each_entry(avc, &vma->anon_vma_chain, same_vma)
+                       anon_vma_interval_tree_verify(avc);
+               vma = vma->vm_next;
                i++;
        }
        if (i != mm->map_count)
@@ -1790,6 +1787,7 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
        }
        vma_unlock_anon_vma(vma);
        khugepaged_enter_vma_merge(vma);
+       validate_mm(vma->vm_mm);
        return error;
 }
 #endif /* CONFIG_STACK_GROWSUP || CONFIG_IA64 */
@@ -1843,6 +1841,7 @@ int expand_downwards(struct vm_area_struct *vma,
        }
        vma_unlock_anon_vma(vma);
        khugepaged_enter_vma_merge(vma);
+       validate_mm(vma->vm_mm);
        return error;
 }