vmscan: report vm_flags in page_referenced()
[sfrench/cifs-2.6.git] / mm / rmap.c
index 316c9d6930ad204b9e8ebae20a84d2a97a0ad67c..c9ccc1a72dc32652827c0d6d81add911f59abbfb 100644 (file)
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -333,7 +333,9 @@ static int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma)
  * repeatedly from either page_referenced_anon or page_referenced_file.
  */
 static int page_referenced_one(struct page *page,
-       struct vm_area_struct *vma, unsigned int *mapcount)
+                              struct vm_area_struct *vma,
+                              unsigned int *mapcount,
+                              unsigned long *vm_flags)
 {
        struct mm_struct *mm = vma->vm_mm;
        unsigned long address;
@@ -381,11 +383,14 @@ out_unmap:
        (*mapcount)--;
        pte_unmap_unlock(pte, ptl);
 out:
+       if (referenced)
+               *vm_flags |= vma->vm_flags;
        return referenced;
 }
 
 static int page_referenced_anon(struct page *page,
-                               struct mem_cgroup *mem_cont)
+                               struct mem_cgroup *mem_cont,
+                               unsigned long *vm_flags)
 {
        unsigned int mapcount;
        struct anon_vma *anon_vma;
@@ -405,7 +410,8 @@ static int page_referenced_anon(struct page *page,
                 */
                if (mem_cont && !mm_match_cgroup(vma->vm_mm, mem_cont))
                        continue;
-               referenced += page_referenced_one(page, vma, &mapcount);
+               referenced += page_referenced_one(page, vma,
+                                                 &mapcount, vm_flags);
                if (!mapcount)
                        break;
        }
@@ -418,6 +424,7 @@ static int page_referenced_anon(struct page *page,
  * page_referenced_file - referenced check for object-based rmap
  * @page: the page we're checking references on.
  * @mem_cont: target memory controller
+ * @vm_flags: collect encountered vma->vm_flags who actually referenced the page
  *
  * For an object-based mapped page, find all the places it is mapped and
  * check/clear the referenced flag.  This is done by following the page->mapping
@@ -427,7 +434,8 @@ static int page_referenced_anon(struct page *page,
  * This function is only called from page_referenced for object-based pages.
  */
 static int page_referenced_file(struct page *page,
-                               struct mem_cgroup *mem_cont)
+                               struct mem_cgroup *mem_cont,
+                               unsigned long *vm_flags)
 {
        unsigned int mapcount;
        struct address_space *mapping = page->mapping;
@@ -467,7 +475,8 @@ static int page_referenced_file(struct page *page,
                 */
                if (mem_cont && !mm_match_cgroup(vma->vm_mm, mem_cont))
                        continue;
-               referenced += page_referenced_one(page, vma, &mapcount);
+               referenced += page_referenced_one(page, vma,
+                                                 &mapcount, vm_flags);
                if (!mapcount)
                        break;
        }
@@ -481,29 +490,35 @@ static int page_referenced_file(struct page *page,
  * @page: the page to test
  * @is_locked: caller holds lock on the page
  * @mem_cont: target memory controller
+ * @vm_flags: collect encountered vma->vm_flags who actually referenced the page
  *
  * Quick test_and_clear_referenced for all mappings to a page,
  * returns the number of ptes which referenced the page.
  */
-int page_referenced(struct page *page, int is_locked,
-                       struct mem_cgroup *mem_cont)
+int page_referenced(struct page *page,
+                   int is_locked,
+                   struct mem_cgroup *mem_cont,
+                   unsigned long *vm_flags)
 {
        int referenced = 0;
 
        if (TestClearPageReferenced(page))
                referenced++;
 
+       *vm_flags = 0;
        if (page_mapped(page) && page->mapping) {
                if (PageAnon(page))
-                       referenced += page_referenced_anon(page, mem_cont);
+                       referenced += page_referenced_anon(page, mem_cont,
+                                                               vm_flags);
                else if (is_locked)
-                       referenced += page_referenced_file(page, mem_cont);
+                       referenced += page_referenced_file(page, mem_cont,
+                                                               vm_flags);
                else if (!trylock_page(page))
                        referenced++;
                else {
                        if (page->mapping)
-                               referenced +=
-                                       page_referenced_file(page, mem_cont);
+                               referenced += page_referenced_file(page,
+                                                       mem_cont, vm_flags);
                        unlock_page(page);
                }
        }