Subject: blkcg: dirty rate accounting
Date: Sat Apr 02 20:15:28 CST 2011

To be used by the balance_dirty_pages() async write IO controller.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
---
 block/blk-cgroup.c         |    4 ++++
 include/linux/blk-cgroup.h |    1 +
 mm/page-writeback.c        |    4 ++++
 3 files changed, 9 insertions(+)

--- linux-next.orig/block/blk-cgroup.c	2011-04-02 20:17:08.000000000 +0800
+++ linux-next/block/blk-cgroup.c	2011-04-02 21:59:24.000000000 +0800
@@ -1458,6 +1458,7 @@ static void blkiocg_destroy(struct cgrou
 
 	free_css_id(&blkio_subsys, &blkcg->css);
 	rcu_read_unlock();
+	percpu_counter_destroy(&blkcg->nr_dirtied);
 	if (blkcg != &blkio_root_cgroup)
 		kfree(blkcg);
 }
@@ -1483,6 +1484,9 @@ done:
 	INIT_HLIST_HEAD(&blkcg->blkg_list);
 
 	INIT_LIST_HEAD(&blkcg->policy_list);
+
+	percpu_counter_init(&blkcg->nr_dirtied, 0);
+
 	return &blkcg->css;
 }
 
--- linux-next.orig/include/linux/blk-cgroup.h	2011-04-02 20:17:08.000000000 +0800
+++ linux-next/include/linux/blk-cgroup.h	2011-04-02 21:59:02.000000000 +0800
@@ -111,6 +111,7 @@ struct blkio_cgroup {
 	spinlock_t lock;
 	struct hlist_head blkg_list;
 	struct list_head policy_list; /* list of blkio_policy_node */
+	struct percpu_counter nr_dirtied;
 };
 
 struct blkio_group_stats {
--- linux-next.orig/mm/page-writeback.c	2011-04-02 20:17:08.000000000 +0800
+++ linux-next/mm/page-writeback.c	2011-04-02 21:59:02.000000000 +0800
@@ -34,6 +34,7 @@
 #include <linux/syscalls.h>
 #include <linux/buffer_head.h>
 #include <linux/pagevec.h>
+#include <linux/blk-cgroup.h>
 #include <trace/events/writeback.h>
 
 /*
@@ -221,6 +222,9 @@ EXPORT_SYMBOL_GPL(bdi_writeout_inc);
 
 void task_dirty_inc(struct task_struct *tsk)
 {
+	struct blkio_cgroup *blkcg = task_to_blkio_cgroup(tsk);
+	if (blkcg)
+		__percpu_counter_add(&blkcg->nr_dirtied, 1, BDI_STAT_BATCH);
 	prop_inc_single(&vm_dirties, &tsk->dirties);
 }