Commit a7eb937b authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

rcutorture: Don't do need_resched() testing if ->sync is NULL 



If cur_ops->sync is NULL, rcu_torture_fwd_prog_nr() will nevertheless
attempt to call through it.  This commit therefore flags cases where
neither need_resched() nor call_rcu() forward-progress testing
can be performed due to NULL function pointers, and also causes
rcu_torture_fwd_prog_nr() to take an early exit if cur_ops->sync()
is NULL.

Reported-by: default avatarTom Rix <trix@redhat.com>
Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent 0d720287

kernel/rcu/rcutorture.c

+5 −3
Original line number Diff line number Diff line
@@ -1923,7 +1923,9 @@ static void rcu_torture_fwd_prog_nr(struct rcu_fwd *rfp, 
	unsigned long stopat;

	static DEFINE_TORTURE_RANDOM(trs);



	if  (cur_ops->call && cur_ops->sync && cur_ops->cb_barrier) {

	if (!cur_ops->sync)

		return; // Cannot do need_resched() forward progress testing without ->sync.

	if (cur_ops->call && cur_ops->cb_barrier) {

		init_rcu_head_on_stack(&fcs.rh);

		selfpropcb = true;

	}
@@ -2149,8 +2151,8 @@ static int __init rcu_torture_fwd_prog_init(void) 


	if (!fwd_progress)

		return 0; /* Not requested, so don't do it. */

	if (!cur_ops->stall_dur || cur_ops->stall_dur() <= 0 ||

	    cur_ops == &rcu_busted_ops) {

	if ((!cur_ops->sync && !cur_ops->call) ||

	    !cur_ops->stall_dur || cur_ops->stall_dur() <= 0 || cur_ops == &rcu_busted_ops) {

		VERBOSE_TOROUT_STRING("rcu_torture_fwd_prog_init: Disabled, unsupported by RCU flavor under test");

		return 0;

	}