Commit-ID: 27c744e32a9a4066daca0ee7496819bff78c1b37
Gitweb: https://git.kernel.org/tip/27c744e32a9a4066daca0ee7496819bff78c1b37
Author: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
AuthorDate: Wed, 27 Jun 2018 21:48:00 -0700
Committer: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
CommitDate: Thu, 30 Aug 2018 16:02:35 -0700
rcu: Allow processing deferred QSes for exiting RCU-preempt readers
If an RCU-preempt read-side critical section is exiting, that is,
->rcu_read_lock_nesting is negative, then it is a good time to look
at the possibility of reporting deferred quiescent states. This
commit therefore updates the checks in rcu_preempt_need_deferred_qs()
to allow exiting critical sections to report deferred quiescent states.
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
kernel/rcu/tree_plugin.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 542791361908..24c209676d20 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -602,7 +602,7 @@ static bool rcu_preempt_need_deferred_qs(struct task_struct *t)
{
return (this_cpu_ptr(&rcu_preempt_data)->deferred_qs ||
READ_ONCE(t->rcu_read_unlock_special.s)) &&
- !t->rcu_read_lock_nesting;
+ t->rcu_read_lock_nesting <= 0;
}
/*
|