[PATCH tip/core/rcu 16/18] rcu: Eliminate redundant NULL-pointer check

From: Paul E. McKenney
Date: Tue Mar 26 2019 - 19:13:28 EST


Because rcu_wake_cond() checks for a null task_struct pointer, there is
no need for its callers to do so. This commit eliminates the redundant
check.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxx>
---
kernel/rcu/tree_plugin.h | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index f0aeb7416dcc..81d3cd821891 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -1191,8 +1191,6 @@ static int rcu_boost_kthread(void *arg)
static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)
__releases(rnp->lock)
{
- struct task_struct *t;
-
raw_lockdep_assert_held_rcu_node(rnp);
if (!rcu_preempt_blocked_readers_cgp(rnp) && rnp->exp_tasks == NULL) {
raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
@@ -1206,9 +1204,8 @@ static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)
if (rnp->exp_tasks == NULL)
rnp->boost_tasks = rnp->gp_tasks;
raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
- t = rnp->boost_kthread_task;
- if (t)
- rcu_wake_cond(t, rnp->boost_kthread_status);
+ rcu_wake_cond(rnp->boost_kthread_task,
+ rnp->boost_kthread_status);
} else {
raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
}
--
2.17.1