mm: simplify lock_page_memcg()

[cascardo/linux.git] / mm / page-writeback.c

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 2b5ea12..d7cf2c5 100644 (file)
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2414,8 +2414,7 @@ int __set_page_dirty_no_writeback(struct page *page)
  *
  * NOTE: This relies on being atomic wrt interrupts.
  */
-void account_page_dirtied(struct page *page, struct address_space *mapping,
-                         struct mem_cgroup *memcg)
+void account_page_dirtied(struct page *page, struct address_space *mapping)
 {
        struct inode *inode = mapping->host;
 
@@ -2427,7 +2426,7 @@ void account_page_dirtied(struct page *page, struct address_space *mapping,
                inode_attach_wb(inode, page);
                wb = inode_to_wb(inode);
 
-               mem_cgroup_inc_page_stat(memcg, MEM_CGROUP_STAT_DIRTY);
+               mem_cgroup_inc_page_stat(page, MEM_CGROUP_STAT_DIRTY);
                __inc_zone_page_state(page, NR_FILE_DIRTY);
                __inc_zone_page_state(page, NR_DIRTIED);
                __inc_wb_stat(wb, WB_RECLAIMABLE);
@@ -2445,10 +2444,10 @@ EXPORT_SYMBOL(account_page_dirtied);
  * Caller must hold lock_page_memcg().
  */
 void account_page_cleaned(struct page *page, struct address_space *mapping,
-                         struct mem_cgroup *memcg, struct bdi_writeback *wb)
+                         struct bdi_writeback *wb)
 {
        if (mapping_cap_account_dirty(mapping)) {
-               mem_cgroup_dec_page_stat(memcg, MEM_CGROUP_STAT_DIRTY);
+               mem_cgroup_dec_page_stat(page, MEM_CGROUP_STAT_DIRTY);
                dec_zone_page_state(page, NR_FILE_DIRTY);
                dec_wb_stat(wb, WB_RECLAIMABLE);
                task_io_account_cancelled_write(PAGE_CACHE_SIZE);
@@ -2469,26 +2468,24 @@ void account_page_cleaned(struct page *page, struct address_space *mapping,
  */
 int __set_page_dirty_nobuffers(struct page *page)
 {
-       struct mem_cgroup *memcg;
-
-       memcg = lock_page_memcg(page);
+       lock_page_memcg(page);
        if (!TestSetPageDirty(page)) {
                struct address_space *mapping = page_mapping(page);
                unsigned long flags;
 
                if (!mapping) {
-                       unlock_page_memcg(memcg);
+                       unlock_page_memcg(page);
                        return 1;
                }
 
                spin_lock_irqsave(&mapping->tree_lock, flags);
                BUG_ON(page_mapping(page) != mapping);
                WARN_ON_ONCE(!PagePrivate(page) && !PageUptodate(page));
-               account_page_dirtied(page, mapping, memcg);
+               account_page_dirtied(page, mapping);
                radix_tree_tag_set(&mapping->page_tree, page_index(page),
                                   PAGECACHE_TAG_DIRTY);
                spin_unlock_irqrestore(&mapping->tree_lock, flags);
-               unlock_page_memcg(memcg);
+               unlock_page_memcg(page);
 
                if (mapping->host) {
                        /* !PageAnon && !swapper_space */
@@ -2496,7 +2493,7 @@ int __set_page_dirty_nobuffers(struct page *page)
                }
                return 1;
        }
-       unlock_page_memcg(memcg);
+       unlock_page_memcg(page);
        return 0;
 }
 EXPORT_SYMBOL(__set_page_dirty_nobuffers);
@@ -2626,17 +2623,16 @@ void cancel_dirty_page(struct page *page)
        if (mapping_cap_account_dirty(mapping)) {
                struct inode *inode = mapping->host;
                struct bdi_writeback *wb;
-               struct mem_cgroup *memcg;
                bool locked;
 
-               memcg = lock_page_memcg(page);
+               lock_page_memcg(page);
                wb = unlocked_inode_to_wb_begin(inode, &locked);
 
                if (TestClearPageDirty(page))
-                       account_page_cleaned(page, mapping, memcg, wb);
+                       account_page_cleaned(page, mapping, wb);
 
                unlocked_inode_to_wb_end(inode, locked);
-               unlock_page_memcg(memcg);
+               unlock_page_memcg(page);
        } else {
                ClearPageDirty(page);
        }
@@ -2667,7 +2663,6 @@ int clear_page_dirty_for_io(struct page *page)
        if (mapping && mapping_cap_account_dirty(mapping)) {
                struct inode *inode = mapping->host;
                struct bdi_writeback *wb;
-               struct mem_cgroup *memcg;
                bool locked;
 
                /*
@@ -2705,16 +2700,16 @@ int clear_page_dirty_for_io(struct page *page)
                 * always locked coming in here, so we get the desired
                 * exclusion.
                 */
-               memcg = lock_page_memcg(page);
+               lock_page_memcg(page);
                wb = unlocked_inode_to_wb_begin(inode, &locked);
                if (TestClearPageDirty(page)) {
-                       mem_cgroup_dec_page_stat(memcg, MEM_CGROUP_STAT_DIRTY);
+                       mem_cgroup_dec_page_stat(page, MEM_CGROUP_STAT_DIRTY);
                        dec_zone_page_state(page, NR_FILE_DIRTY);
                        dec_wb_stat(wb, WB_RECLAIMABLE);
                        ret = 1;
                }
                unlocked_inode_to_wb_end(inode, locked);
-               unlock_page_memcg(memcg);
+               unlock_page_memcg(page);
                return ret;
        }
        return TestClearPageDirty(page);
@@ -2724,10 +2719,9 @@ EXPORT_SYMBOL(clear_page_dirty_for_io);
 int test_clear_page_writeback(struct page *page)
 {
        struct address_space *mapping = page_mapping(page);
-       struct mem_cgroup *memcg;
        int ret;
 
-       memcg = lock_page_memcg(page);
+       lock_page_memcg(page);
        if (mapping) {
                struct inode *inode = mapping->host;
                struct backing_dev_info *bdi = inode_to_bdi(inode);
@@ -2751,21 +2745,20 @@ int test_clear_page_writeback(struct page *page)
                ret = TestClearPageWriteback(page);
        }
        if (ret) {
-               mem_cgroup_dec_page_stat(memcg, MEM_CGROUP_STAT_WRITEBACK);
+               mem_cgroup_dec_page_stat(page, MEM_CGROUP_STAT_WRITEBACK);
                dec_zone_page_state(page, NR_WRITEBACK);
                inc_zone_page_state(page, NR_WRITTEN);
        }
-       unlock_page_memcg(memcg);
+       unlock_page_memcg(page);
        return ret;
 }
 
 int __test_set_page_writeback(struct page *page, bool keep_write)
 {
        struct address_space *mapping = page_mapping(page);
-       struct mem_cgroup *memcg;
        int ret;
 
-       memcg = lock_page_memcg(page);
+       lock_page_memcg(page);
        if (mapping) {
                struct inode *inode = mapping->host;
                struct backing_dev_info *bdi = inode_to_bdi(inode);
@@ -2793,10 +2786,10 @@ int __test_set_page_writeback(struct page *page, bool keep_write)
                ret = TestSetPageWriteback(page);
        }
        if (!ret) {
-               mem_cgroup_inc_page_stat(memcg, MEM_CGROUP_STAT_WRITEBACK);
+               mem_cgroup_inc_page_stat(page, MEM_CGROUP_STAT_WRITEBACK);
                inc_zone_page_state(page, NR_WRITEBACK);
        }
-       unlock_page_memcg(memcg);
+       unlock_page_memcg(page);
        return ret;
 
 }