summaryrefslogtreecommitdiff
path: root/kernel/rcu/tree_plugin.h
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/rcu/tree_plugin.h')
-rw-r--r--kernel/rcu/tree_plugin.h25
1 files changed, 16 insertions, 9 deletions
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index d3db2168598e..6082dd23408f 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -556,16 +556,16 @@ rcu_preempt_deferred_qs_irqrestore(struct task_struct *t, unsigned long flags)
raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
}
- /* Unboost if we were boosted. */
- if (IS_ENABLED(CONFIG_RCU_BOOST) && drop_boost_mutex)
- rt_mutex_futex_unlock(&rnp->boost_mtx.rtmutex);
-
/*
* If this was the last task on the expedited lists,
* then we need to report up the rcu_node hierarchy.
*/
if (!empty_exp && empty_exp_now)
rcu_report_exp_rnp(rnp, true);
+
+ /* Unboost if we were boosted. */
+ if (IS_ENABLED(CONFIG_RCU_BOOST) && drop_boost_mutex)
+ rt_mutex_futex_unlock(&rnp->boost_mtx.rtmutex);
} else {
local_irq_restore(flags);
}
@@ -994,12 +994,15 @@ dump_blkd_tasks(struct rcu_node *rnp, int ncheck)
*/
static void rcu_cpu_kthread_setup(unsigned int cpu)
{
+ struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu);
#ifdef CONFIG_RCU_BOOST
struct sched_param sp;
sp.sched_priority = kthread_prio;
sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
#endif /* #ifdef CONFIG_RCU_BOOST */
+
+ WRITE_ONCE(rdp->rcuc_activity, jiffies);
}
#ifdef CONFIG_RCU_BOOST
@@ -1170,15 +1173,14 @@ static void rcu_spawn_one_boost_kthread(struct rcu_node *rnp)
struct sched_param sp;
struct task_struct *t;
+ mutex_lock(&rnp->boost_kthread_mutex);
if (rnp->boost_kthread_task || !rcu_scheduler_fully_active)
- return;
-
- rcu_state.boost = 1;
+ goto out;
t = kthread_create(rcu_boost_kthread, (void *)rnp,
"rcub/%d", rnp_index);
if (WARN_ON_ONCE(IS_ERR(t)))
- return;
+ goto out;
raw_spin_lock_irqsave_rcu_node(rnp, flags);
rnp->boost_kthread_task = t;
@@ -1186,6 +1188,9 @@ static void rcu_spawn_one_boost_kthread(struct rcu_node *rnp)
sp.sched_priority = kthread_prio;
sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
wake_up_process(t); /* get to TASK_INTERRUPTIBLE quickly. */
+
+ out:
+ mutex_unlock(&rnp->boost_kthread_mutex);
}
/*
@@ -1208,14 +1213,16 @@ static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
return;
if (!zalloc_cpumask_var(&cm, GFP_KERNEL))
return;
+ mutex_lock(&rnp->boost_kthread_mutex);
for_each_leaf_node_possible_cpu(rnp, cpu)
if ((mask & leaf_node_cpu_bit(rnp, cpu)) &&
cpu != outgoingcpu)
cpumask_set_cpu(cpu, cm);
cpumask_and(cm, cm, housekeeping_cpumask(HK_FLAG_RCU));
- if (cpumask_weight(cm) == 0)
+ if (cpumask_empty(cm))
cpumask_copy(cm, housekeeping_cpumask(HK_FLAG_RCU));
set_cpus_allowed_ptr(t, cm);
+ mutex_unlock(&rnp->boost_kthread_mutex);
free_cpumask_var(cm);
}