@@ -1008,9 +1008,7 @@ EXPORT_SYMBOL_GPL(show_rcu_tasks_classic_gp_kthread);
*/
void exit_tasks_rcu_start(void) __acquires(&tasks_rcu_exit_srcu)
{
- preempt_disable();
current->rcu_tasks_idx = __srcu_read_lock(&tasks_rcu_exit_srcu);
- preempt_enable();
}
/*
@@ -1022,9 +1020,7 @@ void exit_tasks_rcu_finish(void) __releases(&tasks_rcu_exit_srcu)
{
struct task_struct *t = current;
- preempt_disable();
__srcu_read_unlock(&tasks_rcu_exit_srcu, t->rcu_tasks_idx);
- preempt_enable();
exit_tasks_rcu_finish_trace(t);
}
Ever since the following commit: 5a41344a3d83 ("srcu: Simplify __srcu_read_unlock() via this_cpu_dec()") SRCU doesn't rely anymore on preemption to be disabled in order to modify the per-CPU counter. And even then it used to be done from the API itself. Therefore and after checking further, it appears to be safe to remove the preemption disablement around __srcu_read_[un]lock() in exit_tasks_rcu_start() and exit_tasks_rcu_finish() Suggested-by: Boqun Feng <boqun.feng@gmail.com> Suggested-by: Paul E. McKenney <paulmck@kernel.org> Suggested-by: Neeraj Upadhyay <quic_neeraju@quicinc.com> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> --- kernel/rcu/tasks.h | 4 ---- 1 file changed, 4 deletions(-)