1 files changed, 19 insertions, 16 deletions

diff --git a/mm/swap_state.c b/mm/swap_state.c
index 3353c9029cef..3ecea98ecb45 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -17,6 +17,7 @@
 #include <linux/backing-dev.h>
 #include <linux/pagevec.h>
 #include <linux/migrate.h>
+#include <linux/page_cgroup.h>
 
 #include <asm/pgtable.h>
 
@@ -72,10 +73,10 @@ int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp_mask)
 {
         int error;
 
-        BUG_ON(!PageLocked(page));
-        BUG_ON(PageSwapCache(page));
-        BUG_ON(PagePrivate(page));
-        BUG_ON(!PageSwapBacked(page));
+        VM_BUG_ON(!PageLocked(page));
+        VM_BUG_ON(PageSwapCache(page));
+        VM_BUG_ON(!PageSwapBacked(page));
+
         error = radix_tree_preload(gfp_mask);
         if (!error) {
                 page_cache_get(page);
@@ -108,10 +109,11 @@ int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp_mask)
  */
 void __delete_from_swap_cache(struct page *page)
 {
-        BUG_ON(!PageLocked(page));
-        BUG_ON(!PageSwapCache(page));
-        BUG_ON(PageWriteback(page));
-        BUG_ON(PagePrivate(page));
+        swp_entry_t ent = {.val = page_private(page)};
+
+        VM_BUG_ON(!PageLocked(page));
+        VM_BUG_ON(!PageSwapCache(page));
+        VM_BUG_ON(PageWriteback(page));
 
         radix_tree_delete(&swapper_space.page_tree, page_private(page));
         set_page_private(page, 0);
@@ -119,6 +121,7 @@ void __delete_from_swap_cache(struct page *page)
         total_swapcache_pages--;
         __dec_zone_page_state(page, NR_FILE_PAGES);
         INC_CACHE_INFO(del_total);
+        mem_cgroup_uncharge_swapcache(page, ent);
 }
 
 /**
@@ -129,13 +132,13 @@ void __delete_from_swap_cache(struct page *page)
  * Allocate swap space for the page and add the page to the
  * swap cache.  Caller needs to hold the page lock. 
  */
-int add_to_swap(struct page * page, gfp_t gfp_mask)
+int add_to_swap(struct page *page)
 {
         swp_entry_t entry;
         int err;
 
-        BUG_ON(!PageLocked(page));
-        BUG_ON(!PageUptodate(page));
+        VM_BUG_ON(!PageLocked(page));
+        VM_BUG_ON(!PageUptodate(page));
 
         for (;;) {
                 entry = get_swap_page();
@@ -154,7 +157,7 @@ int add_to_swap(struct page * page, gfp_t gfp_mask)
                  * Add it to the swap cache and mark it dirty
                  */
                 err = add_to_swap_cache(page, entry,
-                                gfp_mask|__GFP_NOMEMALLOC|__GFP_NOWARN);
+                                __GFP_HIGH|__GFP_NOMEMALLOC|__GFP_NOWARN);
 
                 switch (err) {
                 case 0:                         /* Success */
@@ -196,14 +199,14 @@ void delete_from_swap_cache(struct page *page)
  * If we are the only user, then try to free up the swap cache. 
  * 
  * Its ok to check for PageSwapCache without the page lock
- * here because we are going to recheck again inside 
- * exclusive_swap_page() _with_ the lock. 
+ * here because we are going to recheck again inside
+ * try_to_free_swap() _with_ the lock.
  *                                      - Marcelo
  */
 static inline void free_swap_cache(struct page *page)
 {
-        if (PageSwapCache(page) && trylock_page(page)) {
-                remove_exclusive_swap_page(page);
+        if (PageSwapCache(page) && !page_mapped(page) && trylock_page(page)) {
+                try_to_free_swap(page);
                 unlock_page(page);
         }
 }