[PATCH tip/core/rcu 16/22] rcu: Remove failsafe check for lost quiescent state

From: Paul E. McKenney
Date: Tue Jun 26 2018 - 13:11:56 EST


Now that quiescent-state reporting is fully event-driven, this commit
removes the check for a lost quiescent state from force_qs_rnp().

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
kernel/rcu/tree.c | 16 +++-------------
1 file changed, 3 insertions(+), 13 deletions(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 7de1820a04c1..8704b31b696d 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -2317,8 +2317,9 @@ rcu_report_qs_rnp(unsigned long mask, struct rcu_state *rsp,
* irqs disabled, and this lock is released upon return, but irqs remain
* disabled.
*/
-static void rcu_report_unblock_qs_rnp(struct rcu_state *rsp,
- struct rcu_node *rnp, unsigned long flags)
+static void __maybe_unused
+rcu_report_unblock_qs_rnp(struct rcu_state *rsp,
+ struct rcu_node *rnp, unsigned long flags)
__releases(rnp->lock)
{
unsigned long gps;
@@ -2679,17 +2680,6 @@ static void force_qs_rnp(struct rcu_state *rsp, int (*f)(struct rcu_data *rsp))
/* rcu_initiate_boost() releases rnp->lock */
continue;
}
- if (rnp->parent &&
- (rnp->parent->qsmask & rnp->grpmask)) {
- /*
- * Race between grace-period
- * initialization and task exiting RCU
- * read-side critical section: Report.
- */
- rcu_report_unblock_qs_rnp(rsp, rnp, flags);
- /* rcu_report_unblock_qs_rnp() rlses ->lock */
- continue;
- }
raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
continue;
}
--
2.17.1