1 files changed, 14 insertions, 16 deletions

diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index e6e0cb5..35b0074 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -31,6 +31,7 @@ enum bdi_state {
 	BDI_async_congested,	/* The async (write) queue is getting full */
 	BDI_sync_congested,	/* The sync queue is getting full */
 	BDI_registered,		/* bdi_register() was done */
+	BDI_writeback_running,	/* Writeback is in progress */
 	BDI_unused,		/* Available bits start here */
 };
 
@@ -45,22 +46,21 @@ enum bdi_stat_item {
 #define BDI_STAT_BATCH (8*(1+ilog2(nr_cpu_ids)))
 
 struct bdi_writeback {
-	struct list_head list;			/* hangs off the bdi */
-
-	struct backing_dev_info *bdi;		/* our parent bdi */
+	struct backing_dev_info *bdi;	/* our parent bdi */
 	unsigned int nr;
 
-	unsigned long last_old_flush;		/* last old data flush */
+	unsigned long last_old_flush;	/* last old data flush */
+	unsigned long last_active;	/* last time bdi thread was active */
 
-	struct task_struct	*task;		/* writeback task */
-	struct list_head	b_dirty;	/* dirty inodes */
-	struct list_head	b_io;		/* parked for writeback */
-	struct list_head	b_more_io;	/* parked for more writeback */
+	struct task_struct *task;	/* writeback thread */
+	struct timer_list wakeup_timer; /* used for delayed bdi thread wakeup */
+	struct list_head b_dirty;	/* dirty inodes */
+	struct list_head b_io;		/* parked for writeback */
+	struct list_head b_more_io;	/* parked for more writeback */
 };
 
 struct backing_dev_info {
 	struct list_head bdi_list;
-	struct rcu_head rcu_head;
 	unsigned long ra_pages;	/* max readahead in PAGE_CACHE_SIZE units */
 	unsigned long state;	/* Always use atomic bitops on this */
 	unsigned int capabilities; /* Device capabilities */
@@ -80,10 +80,7 @@ struct backing_dev_info {
 	unsigned int max_ratio, max_prop_frac;
 
 	struct bdi_writeback wb;  /* default writeback info for this bdi */
-	spinlock_t wb_lock;	  /* protects update side of wb_list */
-	struct list_head wb_list; /* the flusher threads hanging off this bdi */
-	unsigned long wb_mask;	  /* bitmask of registered tasks */
-	unsigned int wb_cnt;	  /* number of registered tasks */
+	spinlock_t wb_lock;	  /* protects work_list */
 
 	struct list_head work_list;
 
@@ -105,11 +102,12 @@ int bdi_register(struct backing_dev_info *bdi, struct device *parent,
 int bdi_register_dev(struct backing_dev_info *bdi, dev_t dev);
 void bdi_unregister(struct backing_dev_info *bdi);
 int bdi_setup_and_register(struct backing_dev_info *, char *, unsigned int);
-void bdi_start_writeback(struct backing_dev_info *bdi, struct super_block *sb,
-				long nr_pages, int sb_locked);
-int bdi_writeback_task(struct bdi_writeback *wb);
+void bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages);
+void bdi_start_background_writeback(struct backing_dev_info *bdi);
+int bdi_writeback_thread(void *data);
 int bdi_has_dirty_io(struct backing_dev_info *bdi);
 void bdi_arm_supers_timer(void);
+void bdi_wakeup_thread_delayed(struct backing_dev_info *bdi);
 
 extern spinlock_t bdi_lock;
 extern struct list_head bdi_list;