This commit add lockdep detection for illegal use synchronize_srcu()
in same-type SRCU (or in RCU) read-side critical section and support
early boot operations.
Signed-off-by: Zqiang <qiang1.zhang@xxxxxxxxx>
---
kernel/rcu/srcutiny.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/kernel/rcu/srcutiny.c b/kernel/rcu/srcutiny.c
index 33adafdad261..b12fb0cec44d 100644
--- a/kernel/rcu/srcutiny.c
+++ b/kernel/rcu/srcutiny.c
@@ -197,6 +197,16 @@ void synchronize_srcu(struct srcu_struct *ssp)
{
struct rcu_synchronize rs;
+ RCU_LOCKDEP_WARN(lockdep_is_held(ssp) ||
+ lock_is_held(&rcu_bh_lock_map) ||
+ lock_is_held(&rcu_lock_map) ||
+ lock_is_held(&rcu_sched_lock_map),
+ "Illegal synchronize_srcu() in same-type SRCU (or in RCU) read-side critical section");
+
+ if (rcu_scheduler_active == RCU_SCHEDULER_INACTIVE)
+ return;
+
+ might_sleep();
init_rcu_head_on_stack(&rs.head);
init_completion(&rs.completion);
call_srcu(ssp, &rs.head, wakeme_after_rcu);
--
2.25.1
