[PATCH v2 tip/core/rcu 18/18] rcu: Add lockdep checks to synchronous expedited primitives

Paul E. McKenney
2017-01-18T03:53:21Z

The non-expedited synchronize_*rcu() primitives have lockdep checks, but
their expedited counterparts lack these checks. This commit therefore
adds these checks to the expedited synchronize_*rcu() primitives.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
---
kernel/rcu/tree_exp.h | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h
index 303df97bbfc5..f3e214898e3a 100644
--- a/kernel/rcu/tree_exp.h
+++ b/kernel/rcu/tree_exp.h
@@ -639,6 +639,11 @@ void synchronize_sched_expedited(void)
{
struct rcu_state *rsp = &rcu_sched_state;

+ RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map) ||
+ lock_is_held(&rcu_lock_map) ||
+ lock_is_held(&rcu_sched_lock_map),
+ "Illegal synchronize_sched_expedited() in RCU read-side critical section");
+
/* If only one CPU, this is automatically a grace period. */
if (rcu_blocking_is_gp())
return;
@@ -708,6 +713,11 @@ void synchronize_rcu_expedited(void)
{
struct rcu_state *rsp = rcu_state_p;

+ RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map) ||
+ lock_is_held(&rcu_lock_map) ||
+ lock_is_held(&rcu_sched_lock_map),
+ "Illegal synchronize_rcu_expedited() in RCU read-side critical section");
+
if (rcu_scheduler_active == RCU_SCHEDULER_INACTIVE)
return;
_synchronize_rcu_expedited(rsp, sync_rcu_exp_handler);
--
2.5.2