rcu: Add destroy_work_on_stack() to match INIT_WORK_ONSTACK()

The synchronize_rcu_expedited() function has an INIT_WORK_ONSTACK(),
but lacks the corresponding destroy_work_on_stack().  This commit
therefore adds destroy_work_on_stack().

Reported-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Acked-by: Andrea Arcangeli <aarcange@redhat.com>

diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h
index af7e7b9c86afac1da4984f3f8bb81b292298cc4f..513b403b683b7105686e3f915e9a771fe135dc6b 100644 (file)
--- a/kernel/rcu/tree_exp.h
+++ b/kernel/rcu/tree_exp.h
@@ -792,6 +792,7 @@ static int rcu_print_task_exp_stall(struct rcu_node *rnp)
  */
 void synchronize_rcu_expedited(void)
 {
+       bool boottime = (rcu_scheduler_active == RCU_SCHEDULER_INIT);
        struct rcu_exp_work rew;
        struct rcu_node *rnp;
        unsigned long s;
@@ -817,7 +818,7 @@ void synchronize_rcu_expedited(void)
                return;  /* Someone else did our work for us. */
 
        /* Ensure that load happens before action based on it. */
-       if (unlikely(rcu_scheduler_active == RCU_SCHEDULER_INIT)) {
+       if (unlikely(boottime)) {
                /* Direct call during scheduler init and early_initcalls(). */
                rcu_exp_sel_wait_wake(s);
        } else {
@@ -835,5 +836,8 @@ void synchronize_rcu_expedited(void)
 
        /* Let the next expedited grace period start. */
        mutex_unlock(&rcu_state.exp_mutex);
+
+       if (likely(!boottime))
+               destroy_work_on_stack(&rew.rew_work);
 }
 EXPORT_SYMBOL_GPL(synchronize_rcu_expedited);