[PATCH 7/8] rcu/srcutiny: don't return before reenabling preemption

Frederic Weisbecker posted 8 patches 2 weeks, 3 days ago
[PATCH 7/8] rcu/srcutiny: don't return before reenabling preemption
Posted by Frederic Weisbecker 2 weeks, 3 days ago
From: Michal Schmidt <mschmidt@redhat.com>

Code after the return statement is dead. Enable preemption before
returning from srcu_drive_gp().

This will be important when/if PREEMPT_AUTO (lazy resched) gets merged.

Fixes: 65b4a59557f6 ("srcu: Make Tiny SRCU explicitly disable preemption")
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
---
 kernel/rcu/srcutiny.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/rcu/srcutiny.c b/kernel/rcu/srcutiny.c
index 549c03336ee9..4dcbf8aa80ff 100644
--- a/kernel/rcu/srcutiny.c
+++ b/kernel/rcu/srcutiny.c
@@ -122,8 +122,8 @@ void srcu_drive_gp(struct work_struct *wp)
 	ssp = container_of(wp, struct srcu_struct, srcu_work);
 	preempt_disable();  // Needed for PREEMPT_AUTO
 	if (ssp->srcu_gp_running || ULONG_CMP_GE(ssp->srcu_idx, READ_ONCE(ssp->srcu_idx_max))) {
+		preempt_enable();
 		return; /* Already running or nothing to do. */
-		preempt_enable();
 	}
 
 	/* Remove recently arrived callbacks and wait for readers. */
-- 
2.46.0