CAPI: Convert capidev_list_lock into a mutex

[safe/jmp/linux-2.6] / mm / rmap.c

diff --git a/mm/rmap.c b/mm/rmap.c
index c81bedd..278cd27 100644 (file)
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -721,7 +721,7 @@ void page_add_file_rmap(struct page *page)
 {
        if (atomic_inc_and_test(&page->_mapcount)) {
                __inc_zone_page_state(page, NR_FILE_MAPPED);
-               mem_cgroup_update_mapped_file_stat(page, 1);
+               mem_cgroup_update_file_mapped(page, 1);
        }
 }
 
@@ -753,8 +753,8 @@ void page_remove_rmap(struct page *page)
                __dec_zone_page_state(page, NR_ANON_PAGES);
        } else {
                __dec_zone_page_state(page, NR_FILE_MAPPED);
+               mem_cgroup_update_file_mapped(page, -1);
        }
-       mem_cgroup_update_mapped_file_stat(page, -1);
        /*
         * It would be tidy to reset the PageAnon mapping here,
         * but that might overwrite a racing page_add_anon_rmap
@@ -789,10 +789,9 @@ int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
         * skipped over this mm) then we should reactivate it.
         */
        if (!(flags & TTU_IGNORE_MLOCK)) {
-               if (vma->vm_flags & VM_LOCKED) {
-                       ret = SWAP_MLOCK;
-                       goto out_unmap;
-               }
+               if (vma->vm_flags & VM_LOCKED)
+                       goto out_mlock;
+
                if (TTU_ACTION(flags) == TTU_MUNLOCK)
                        goto out_unmap;
        }
@@ -865,18 +864,28 @@ int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 
 out_unmap:
        pte_unmap_unlock(pte, ptl);
+out:
+       return ret;
 
-       if (ret == SWAP_MLOCK) {
-               ret = SWAP_AGAIN;
-               if (down_read_trylock(&vma->vm_mm->mmap_sem)) {
-                       if (vma->vm_flags & VM_LOCKED) {
-                               mlock_vma_page(page);
-                               ret = SWAP_MLOCK;
-                       }
-                       up_read(&vma->vm_mm->mmap_sem);
+out_mlock:
+       pte_unmap_unlock(pte, ptl);
+
+
+       /*
+        * We need mmap_sem locking, Otherwise VM_LOCKED check makes
+        * unstable result and race. Plus, We can't wait here because
+        * we now hold anon_vma->lock or mapping->i_mmap_lock.
+        * if trylock failed, the page remain in evictable lru and later
+        * vmscan could retry to move the page to unevictable lru if the
+        * page is actually mlocked.
+        */
+       if (down_read_trylock(&vma->vm_mm->mmap_sem)) {
+               if (vma->vm_flags & VM_LOCKED) {
+                       mlock_vma_page(page);
+                       ret = SWAP_MLOCK;
                }
+               up_read(&vma->vm_mm->mmap_sem);
        }
-out:
        return ret;
 }