torture: Allow inter-stutter interval to be specified

Currently, the inter-stutter interval is the same as the stutter duration,
that is, whatever number of jiffies is passed into torture_stutter_init().
This has worked well for quite some time, but the addition of
forward-progress testing to rcutorture can delay processes for several
seconds, which can triple the time that they are stuttered.

This commit therefore adds a second argument to torture_stutter_init()
that specifies the inter-stutter interval.  While locktorture preserves
the current behavior, rcutorture uses the RCU CPU stall warning interval
to provide a wider inter-stutter interval.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit is contained in:
Paul E. McKenney
2019-04-09 14:44:49 -07:00
parent e8516c64fe
commit ff3bf92d90
4 changed files with 10 additions and 5 deletions

View File

@@ -570,6 +570,7 @@ static void torture_shutdown_cleanup(void)
static struct task_struct *stutter_task;
static int stutter_pause_test;
static int stutter;
static int stutter_gap;
/*
* Block until the stutter interval ends. This must be called periodically
@@ -621,7 +622,7 @@ static int torture_stutter(void *arg)
}
WRITE_ONCE(stutter_pause_test, 0);
if (!torture_must_stop())
schedule_timeout_interruptible(stutter);
schedule_timeout_interruptible(stutter_gap);
torture_shutdown_absorb("torture_stutter");
} while (!torture_must_stop());
torture_kthread_stopping("torture_stutter");
@@ -631,9 +632,10 @@ static int torture_stutter(void *arg)
/*
* Initialize and kick off the torture_stutter kthread.
*/
int torture_stutter_init(const int s)
int torture_stutter_init(const int s, const int sgap)
{
stutter = s;
stutter_gap = sgap;
return torture_create_kthread(torture_stutter, NULL, stutter_task);
}
EXPORT_SYMBOL_GPL(torture_stutter_init);