rcu: Remove rsp parameter from rcu_spawn_one_boost_kthread()

There now is only one rcu_state structure in a given build of the
Linux kernel, so there is no need to pass it as a parameter to RCU's
functions.  This commit therefore removes the rsp parameter from
rcu_spawn_one_boost_kthread().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index ccdee6b..dc1c337 100644 (file)
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -463,10 +463,6 @@ static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
 static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
 static void invoke_rcu_callbacks_kthread(void);
 static bool rcu_is_callbacks_kthread(void);
-#ifdef CONFIG_RCU_BOOST
-static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
-                                                struct rcu_node *rnp);
-#endif /* #ifdef CONFIG_RCU_BOOST */
 static void __init rcu_spawn_boost_kthreads(void);
 static void rcu_prepare_kthreads(int cpu);
 static void rcu_cleanup_after_idle(void);

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 9a3d301..9a6dea5 100644 (file)
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -1290,21 +1290,20 @@ static void rcu_preempt_boost_start_gp(struct rcu_node *rnp)
  * already exist.  We only create this kthread for preemptible RCU.
  * Returns zero if all is well, a negated errno otherwise.
  */
-static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
-                                      struct rcu_node *rnp)
+static int rcu_spawn_one_boost_kthread(struct rcu_node *rnp)
 {
-       int rnp_index = rnp - &rsp->node[0];
+       int rnp_index = rnp - rcu_get_root();
        unsigned long flags;
        struct sched_param sp;
        struct task_struct *t;
 
-       if (&rcu_state != rsp)
+       if (!IS_ENABLED(CONFIG_PREEMPT_RCU))
                return 0;
 
        if (!rcu_scheduler_fully_active || rcu_rnp_online_cpus(rnp) == 0)
                return 0;
 
-       rsp->boost = 1;
+       rcu_state.boost = 1;
        if (rnp->boost_kthread_task != NULL)
                return 0;
        t = kthread_create(rcu_boost_kthread, (void *)rnp,
@@ -1430,7 +1429,7 @@ static void __init rcu_spawn_boost_kthreads(void)
                per_cpu(rcu_cpu_has_work, cpu) = 0;
        BUG_ON(smpboot_register_percpu_thread(&rcu_cpu_thread_spec));
        rcu_for_each_leaf_node(&rcu_state, rnp)
-               (void)rcu_spawn_one_boost_kthread(&rcu_state, rnp);
+               (void)rcu_spawn_one_boost_kthread(rnp);
 }
 
 static void rcu_prepare_kthreads(int cpu)
@@ -1440,7 +1439,7 @@ static void rcu_prepare_kthreads(int cpu)
 
        /* Fire up the incoming CPU's kthread and leaf rcu_node kthread. */
        if (rcu_scheduler_fully_active)
-               (void)rcu_spawn_one_boost_kthread(&rcu_state, rnp);
+               (void)rcu_spawn_one_boost_kthread(rnp);
 }
 
 #else /* #ifdef CONFIG_RCU_BOOST */