Commit 43b39caf authored by Zqiang's avatar Zqiang Committed by Paul E. McKenney
Browse files

rcutorture: Make rcutorture support srcu double call test 

This commit allows rcutorture to test double-call_srcu() when the
CONFIG_DEBUG_OBJECTS_RCU_HEAD Kconfig option is enabled.  The non-raw
sdp structure's ->spinlock will be acquired in call_srcu(), hence this
commit also removes the current IRQ and preemption disabling so as to
avoid lockdep complaints.

Link: https://lore.kernel.org/all/20240407112714.24460-1-qiang.zhang1211@gmail.com/



Signed-off-by: default avatarZqiang <qiang.zhang1211@gmail.com>
Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent 1613e604

kernel/rcu/rcutorture.c

+26 −20
Original line number Diff line number Diff line
@@ -390,6 +390,7 @@ struct rcu_torture_ops { 
	int extendables;

	int slow_gps;

	int no_pi_lock;

	int debug_objects;

	const char *name;

};
@@ -577,6 +578,7 @@ static struct rcu_torture_ops rcu_ops = { 
	.irq_capable		= 1,

	.can_boost		= IS_ENABLED(CONFIG_RCU_BOOST),

	.extendables		= RCUTORTURE_MAX_EXTEND,

	.debug_objects		= 1,

	.name			= "rcu"

};
@@ -747,6 +749,7 @@ static struct rcu_torture_ops srcu_ops = { 
	.cbflood_max	= 50000,

	.irq_capable	= 1,

	.no_pi_lock	= IS_ENABLED(CONFIG_TINY_SRCU),

	.debug_objects	= 1,

	.name		= "srcu"

};
@@ -786,6 +789,7 @@ static struct rcu_torture_ops srcud_ops = { 
	.cbflood_max	= 50000,

	.irq_capable	= 1,

	.no_pi_lock	= IS_ENABLED(CONFIG_TINY_SRCU),

	.debug_objects	= 1,

	.name		= "srcud"

};
@@ -3455,7 +3459,6 @@ rcu_torture_cleanup(void) 
		cur_ops->gp_slow_unregister(NULL);

}



#ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD

static void rcu_torture_leak_cb(struct rcu_head *rhp)

{

}
@@ -3473,7 +3476,6 @@ static void rcu_torture_err_cb(struct rcu_head *rhp) 
	 */

	pr_alert("%s: duplicated callback was invoked.\n", KBUILD_MODNAME);

}

#endif /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */



/*

 * Verify that double-free causes debug-objects to complain, but only
@@ -3482,39 +3484,43 @@ static void rcu_torture_err_cb(struct rcu_head *rhp) 
 */

static void rcu_test_debug_objects(void)

{

#ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD

	struct rcu_head rh1;

	struct rcu_head rh2;

	int idx;



	if (!IS_ENABLED(CONFIG_DEBUG_OBJECTS_RCU_HEAD)) {

		pr_alert("%s: !CONFIG_DEBUG_OBJECTS_RCU_HEAD, not testing duplicate call_%s()\n",

					KBUILD_MODNAME, cur_ops->name);

		return;

	}



	if (WARN_ON_ONCE(cur_ops->debug_objects &&

			(!cur_ops->call || !cur_ops->cb_barrier)))

		return;



	struct rcu_head *rhp = kmalloc(sizeof(*rhp), GFP_KERNEL);



	init_rcu_head_on_stack(&rh1);

	init_rcu_head_on_stack(&rh2);

	pr_alert("%s: WARN: Duplicate call_rcu() test starting.\n", KBUILD_MODNAME);

	pr_alert("%s: WARN: Duplicate call_%s() test starting.\n", KBUILD_MODNAME, cur_ops->name);



	/* Try to queue the rh2 pair of callbacks for the same grace period. */

	preempt_disable(); /* Prevent preemption from interrupting test. */

	rcu_read_lock(); /* Make it impossible to finish a grace period. */

	call_rcu_hurry(&rh1, rcu_torture_leak_cb); /* Start grace period. */

	local_irq_disable(); /* Make it harder to start a new grace period. */

	call_rcu_hurry(&rh2, rcu_torture_leak_cb);

	call_rcu_hurry(&rh2, rcu_torture_err_cb); /* Duplicate callback. */

	idx = cur_ops->readlock(); /* Make it impossible to finish a grace period. */

	cur_ops->call(&rh1, rcu_torture_leak_cb); /* Start grace period. */

	cur_ops->call(&rh2, rcu_torture_leak_cb);

	cur_ops->call(&rh2, rcu_torture_err_cb); /* Duplicate callback. */

	if (rhp) {

		call_rcu_hurry(rhp, rcu_torture_leak_cb);

		call_rcu_hurry(rhp, rcu_torture_err_cb); /* Another duplicate callback. */

		cur_ops->call(rhp, rcu_torture_leak_cb);

		cur_ops->call(rhp, rcu_torture_err_cb); /* Another duplicate callback. */

	}

	local_irq_enable();

	rcu_read_unlock();

	preempt_enable();

	cur_ops->readunlock(idx);



	/* Wait for them all to get done so we can safely return. */

	rcu_barrier();

	pr_alert("%s: WARN: Duplicate call_rcu() test complete.\n", KBUILD_MODNAME);

	cur_ops->cb_barrier();

	pr_alert("%s: WARN: Duplicate call_%s() test complete.\n", KBUILD_MODNAME, cur_ops->name);

	destroy_rcu_head_on_stack(&rh1);

	destroy_rcu_head_on_stack(&rh2);

	kfree(rhp);

#else /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */

	pr_alert("%s: !CONFIG_DEBUG_OBJECTS_RCU_HEAD, not testing duplicate call_rcu()\n", KBUILD_MODNAME);

#endif /* #else #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */

}



static void rcutorture_sync(void)