rcutorture: Add RCU-tasks qualifier to dereference

Although RCU-tasks isn't really designed to support rcu_dereference()
and list manipulation, that is how rcutorture tests it.  Which means
that lockdep-RCU complains about the rcu_dereference_check() invocations
because RCU-tasks doesn't have read-side markers.  This commit therefore
creates a torturing_tasks() to silence the lockdep-RCU complaints from
rcu_dereference_check() when RCU-tasks is being tortured.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit is contained in:
Paul E. McKenney 2015-06-30 08:57:57 -07:00
parent 3a0af33341
commit 5be5d1a117
1 changed files with 14 additions and 2 deletions

View File

@ -684,10 +684,20 @@ static struct rcu_torture_ops tasks_ops = {
#define RCUTORTURE_TASKS_OPS &tasks_ops,
static bool __maybe_unused torturing_tasks(void)
{
return cur_ops == &tasks_ops;
}
#else /* #ifdef CONFIG_TASKS_RCU */
#define RCUTORTURE_TASKS_OPS
static bool torturing_tasks(void)
{
return false;
}
#endif /* #else #ifdef CONFIG_TASKS_RCU */
/*
@ -1087,7 +1097,8 @@ static void rcu_torture_timer(unsigned long unused)
p = rcu_dereference_check(rcu_torture_current,
rcu_read_lock_bh_held() ||
rcu_read_lock_sched_held() ||
srcu_read_lock_held(srcu_ctlp));
srcu_read_lock_held(srcu_ctlp) ||
torturing_tasks());
if (p == NULL) {
/* Leave because rcu_torture_writer is not yet underway */
cur_ops->readunlock(idx);
@ -1161,7 +1172,8 @@ rcu_torture_reader(void *arg)
p = rcu_dereference_check(rcu_torture_current,
rcu_read_lock_bh_held() ||
rcu_read_lock_sched_held() ||
srcu_read_lock_held(srcu_ctlp));
srcu_read_lock_held(srcu_ctlp) ||
torturing_tasks());
if (p == NULL) {
/* Wait for rcu_torture_writer to get underway */
cur_ops->readunlock(idx);