Commit e086481b authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

rcutorture: Add a lock_busted to test the test 



This commit adds a maximally broken locking primitive in which
lock acquisition and release are both no-ops.

Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: default avatarJosh Triplett <josh@joshtriplett.org>
parent b46f358a

kernel/locking/locktorture.c

+32 −1
Original line number Diff line number Diff line
@@ -112,6 +112,37 @@ static struct lock_torture_ops *cur_ops; 
 * Definitions for lock torture testing.

 */



static int torture_lock_busted_write_lock(void)

{

	return 0;  /* BUGGY, do not use in real life!!! */

}



static void torture_lock_busted_write_delay(struct torture_random_state *trsp)

{

	const unsigned long longdelay_us = 100;



	/* We want a long delay occasionally to force massive contention.  */

	if (!(torture_random(trsp) %

	      (nrealwriters_stress * 2000 * longdelay_us)))

		mdelay(longdelay_us);

#ifdef CONFIG_PREEMPT

	if (!(torture_random(trsp) % (nrealwriters_stress * 20000)))

		preempt_schedule();  /* Allow test to be preempted. */

#endif

}



static void torture_lock_busted_write_unlock(void)

{

	  /* BUGGY, do not use in real life!!! */

}



static struct lock_torture_ops lock_busted_ops = {

	.writelock	= torture_lock_busted_write_lock,

	.write_delay	= torture_lock_busted_write_delay,

	.writeunlock	= torture_lock_busted_write_unlock,

	.name		= "lock_busted"

};



static DEFINE_SPINLOCK(torture_spinlock);



static int torture_spin_lock_write_lock(void) __acquires(torture_spinlock)
@@ -320,7 +351,7 @@ static int __init lock_torture_init(void) 
	int i;

	int firsterr = 0;

	static struct lock_torture_ops *torture_ops[] = {

		&spin_lock_ops, &spin_lock_irq_ops,

		&lock_busted_ops, &spin_lock_ops, &spin_lock_irq_ops,

	};



	torture_init_begin(torture_type, verbose, &locktorture_runnable);