fs: add dirtytime_expire_seconds sysctl

Add a tuning knob so we can adjust the dirtytime expiration timeout,
which is very useful for testing lazytime.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>

1 files changed, 8 insertions, 0 deletions

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 88ea2d6..ce410bb 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1228,6 +1228,14 @@ static struct ctl_table vm_table[] = {
 		.extra1		= &zero,
 	},
 	{
+		.procname	= "dirtytime_expire_seconds",
+		.data		= &dirtytime_expire_interval,
+		.maxlen		= sizeof(dirty_expire_interval),
+		.mode		= 0644,
+		.proc_handler	= dirtytime_interval_handler,
+		.extra1		= &zero,
+	},
+	{
 		.procname       = "nr_pdflush_threads",
 		.mode           = 0444 /* read-only */,
 		.proc_handler   = pdflush_proc_obsolete,