mm: dirty page tracking race fix
[linux-2.6.git] / mm / swap_state.c
index 3e3381d..797c383 100644 (file)
@@ -39,7 +39,7 @@ static struct backing_dev_info swap_backing_dev_info = {
 
 struct address_space swapper_space = {
        .page_tree      = RADIX_TREE_INIT(GFP_ATOMIC|__GFP_NOWARN),
-       .tree_lock      = __RW_LOCK_UNLOCKED(swapper_space.tree_lock),
+       .tree_lock      = __SPIN_LOCK_UNLOCKED(swapper_space.tree_lock),
        .a_ops          = &swap_aops,
        .i_mmap_nonlinear = LIST_HEAD_INIT(swapper_space.i_mmap_nonlinear),
        .backing_dev_info = &swap_backing_dev_info,
@@ -56,10 +56,11 @@ static struct {
 
 void show_swap_cache_info(void)
 {
-       printk("Swap cache: add %lu, delete %lu, find %lu/%lu\n",
+       printk("%lu pages in swap cache\n", total_swapcache_pages);
+       printk("Swap cache stats: add %lu, delete %lu, find %lu/%lu\n",
                swap_cache_info.add_total, swap_cache_info.del_total,
                swap_cache_info.find_success, swap_cache_info.find_total);
-       printk("Free swap  = %lukB\n", nr_swap_pages << (PAGE_SHIFT - 10));
+       printk("Free swap  = %ldkB\n", nr_swap_pages << (PAGE_SHIFT - 10));
        printk("Total swap = %lukB\n", total_swap_pages << (PAGE_SHIFT - 10));
 }
 
@@ -80,7 +81,7 @@ int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp_mask)
                SetPageSwapCache(page);
                set_page_private(page, entry.val);
 
-               write_lock_irq(&swapper_space.tree_lock);
+               spin_lock_irq(&swapper_space.tree_lock);
                error = radix_tree_insert(&swapper_space.page_tree,
                                                entry.val, page);
                if (likely(!error)) {
@@ -88,7 +89,7 @@ int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp_mask)
                        __inc_zone_page_state(page, NR_FILE_PAGES);
                        INC_CACHE_INFO(add_total);
                }
-               write_unlock_irq(&swapper_space.tree_lock);
+               spin_unlock_irq(&swapper_space.tree_lock);
                radix_tree_preload_end();
 
                if (unlikely(error)) {
@@ -182,9 +183,9 @@ void delete_from_swap_cache(struct page *page)
 
        entry.val = page_private(page);
 
-       write_lock_irq(&swapper_space.tree_lock);
+       spin_lock_irq(&swapper_space.tree_lock);
        __delete_from_swap_cache(page);
-       write_unlock_irq(&swapper_space.tree_lock);
+       spin_unlock_irq(&swapper_space.tree_lock);
 
        swap_free(entry);
        page_cache_release(page);
@@ -200,7 +201,7 @@ void delete_from_swap_cache(struct page *page)
  */
 static inline void free_swap_cache(struct page *page)
 {
-       if (PageSwapCache(page) && !TestSetPageLocked(page)) {
+       if (PageSwapCache(page) && trylock_page(page)) {
                remove_exclusive_swap_page(page);
                unlock_page(page);
        }
@@ -301,9 +302,9 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
                 * re-using the just freed swap entry for an existing page.
                 * May fail (-ENOMEM) if radix-tree node allocation failed.
                 */
-               SetPageLocked(new_page);
+               set_page_locked(new_page);
                err = add_to_swap_cache(new_page, entry, gfp_mask & GFP_KERNEL);
-               if (!err) {
+               if (likely(!err)) {
                        /*
                         * Initiate read into locked page and return.
                         */
@@ -311,7 +312,7 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
                        swap_readpage(NULL, new_page);
                        return new_page;
                }
-               ClearPageLocked(new_page);
+               clear_page_locked(new_page);
                swap_free(entry);
        } while (err != -ENOMEM);