[PATCH -next 09/15] fs: fs-writeback: move sysctl to its own file

The dirtytime_expire_interval belongs to fs/fs-writeback.c, move it into
its own file from /kernel/sysctl.c. And remove the useless extern variable
declaration and the function declaration from include/linux/writeback.h

Signed-off-by: Kaixiong Yu <[email protected]>
---
 fs/fs-writeback.c         | 28 ++++++++++++++++++++--------
 include/linux/writeback.h |  4 ----
 kernel/sysctl.c           |  8 --------
 3 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 1a5006329f6f..71ff73552323 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -2400,14 +2400,7 @@ static void wakeup_dirtytime_writeback(struct work_struct *w)
 	schedule_delayed_work(&dirtytime_work, dirtytime_expire_interval * HZ);
 }
 
-static int __init start_dirtytime_writeback(void)
-{
-	schedule_delayed_work(&dirtytime_work, dirtytime_expire_interval * HZ);
-	return 0;
-}
-__initcall(start_dirtytime_writeback);
-
-int dirtytime_interval_handler(const struct ctl_table *table, int write,
+static int dirtytime_interval_handler(const struct ctl_table *table, int write,
 			       void *buffer, size_t *lenp, loff_t *ppos)
 {
 	int ret;
@@ -2418,6 +2411,25 @@ int dirtytime_interval_handler(const struct ctl_table *table, int write,
 	return ret;
 }
 
+static struct ctl_table vm_fs_writeback_table[] = {
+	{
+		.procname	= "dirtytime_expire_seconds",
+		.data		= &dirtytime_expire_interval,
+		.maxlen		= sizeof(dirtytime_expire_interval),
+		.mode		= 0644,
+		.proc_handler	= dirtytime_interval_handler,
+		.extra1		= SYSCTL_ZERO,
+	},
+};
+
+static int __init start_dirtytime_writeback(void)
+{
+	schedule_delayed_work(&dirtytime_work, dirtytime_expire_interval * HZ);
+	register_sysctl_init("vm", vm_fs_writeback_table);
+	return 0;
+}
+__initcall(start_dirtytime_writeback);
+
 /**
  * __mark_inode_dirty -	internal function to mark an inode dirty
  *
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index 21dac644d325..22bc047ed91e 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -351,12 +351,8 @@ extern struct wb_domain global_wb_domain;
 /* These are exported to sysctl. */
 extern unsigned int dirty_writeback_interval;
 extern unsigned int dirty_expire_interval;
-extern unsigned int dirtytime_expire_interval;
 extern int laptop_mode;
 
-int dirtytime_interval_handler(const struct ctl_table *table, int write,
-		void *buffer, size_t *lenp, loff_t *ppos);
-
 void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty);
 unsigned long wb_calc_thresh(struct bdi_writeback *wb, unsigned long thresh);
 unsigned long cgwb_calc_thresh(struct bdi_writeback *wb);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index d3de31ec74bf..373e018b950c 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2024,14 +2024,6 @@ static struct ctl_table kern_table[] = {
 };
 
 static struct ctl_table vm_table[] = {
-	{
-		.procname	= "dirtytime_expire_seconds",
-		.data		= &dirtytime_expire_interval,
-		.maxlen		= sizeof(dirtytime_expire_interval),
-		.mode		= 0644,
-		.proc_handler	= dirtytime_interval_handler,
-		.extra1		= SYSCTL_ZERO,
-	},
 	{
 		.procname	= "drop_caches",
 		.data		= &sysctl_drop_caches,
-- 
2.25.1