Commit ed7d2f1a authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

rcutorture: Allow per-RCU-flavor polled double-GP check 



Only vanilla RCU needs a double grace period for its compressed
polled grace-period old-state cookie.  This commit therefore adds an
rcu_torture_ops per-flavor function ->poll_need_2gp to allow this check
to be adapted to the RCU flavor under test.  A NULL pointer for this
function says that doubled grace periods are never needed.

Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent ccb42229

kernel/rcu/rcutorture.c

+8 −1
Original line number Diff line number Diff line
@@ -341,6 +341,7 @@ struct rcu_torture_ops { 
	unsigned long (*start_gp_poll)(void);

	bool (*poll_gp_state)(unsigned long oldstate);

	bool (*poll_gp_state_full)(struct rcu_gp_oldstate *rgosp);

	bool (*poll_need_2gp)(bool poll, bool poll_full);

	void (*cond_sync)(unsigned long oldstate);

	call_rcu_func_t call;

	void (*cb_barrier)(void);
@@ -492,6 +493,11 @@ static void rcu_sync_torture_init(void) 
	INIT_LIST_HEAD(&rcu_torture_removed);

}



static bool rcu_poll_need_2gp(bool poll, bool poll_full)

{

	return poll || (!IS_ENABLED(CONFIG_TINY_RCU) && poll_full && num_online_cpus() <= 1);

}



static struct rcu_torture_ops rcu_ops = {

	.ttype			= RCU_FLAVOR,

	.init			= rcu_sync_torture_init,
@@ -511,6 +517,7 @@ static struct rcu_torture_ops rcu_ops = { 
	.start_gp_poll		= start_poll_synchronize_rcu,

	.poll_gp_state		= poll_state_synchronize_rcu,

	.poll_gp_state_full	= poll_state_synchronize_rcu_full,

	.poll_need_2gp		= rcu_poll_need_2gp,

	.cond_sync		= cond_synchronize_rcu,

	.get_gp_state_exp	= get_state_synchronize_rcu,

	.start_gp_poll_exp	= start_poll_synchronize_rcu_expedited,
@@ -1228,7 +1235,7 @@ static void do_rtws_sync(struct torture_random_state *trsp, void (*sync)(void)) 
		cookie = cur_ops->get_gp_state();

	if (dopoll_full)

		cur_ops->get_gp_state_full(&cookie_full);

	if (dopoll || (!IS_ENABLED(CONFIG_TINY_RCU) && dopoll_full && num_online_cpus() <= 1))

	if (cur_ops->poll_need_2gp && cur_ops->poll_need_2gp(dopoll, dopoll_full))

		sync();

	sync();

	WARN_ONCE(dopoll && !cur_ops->poll_gp_state(cookie),