1 files changed, 46 insertions, 1 deletions

diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index f5e6a2f95a2a..624ff75e08ab 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -144,8 +144,45 @@ bool rcu_gp_is_normal(void)
 }
 EXPORT_SYMBOL_GPL(rcu_gp_is_normal);
 
-static atomic_t rcu_expedited_nesting = ATOMIC_INIT(1);
+static atomic_t rcu_async_hurry_nesting = ATOMIC_INIT(1);
+/*
+ * Should call_rcu() callbacks be processed with urgency or are
+ * they OK being executed with arbitrary delays?
+ */
+bool rcu_async_should_hurry(void)
+{
+	return !IS_ENABLED(CONFIG_RCU_LAZY) ||
+	       atomic_read(&rcu_async_hurry_nesting);
+}
+EXPORT_SYMBOL_GPL(rcu_async_should_hurry);
+
+/**
+ * rcu_async_hurry - Make future async RCU callbacks not lazy.
+ *
+ * After a call to this function, future calls to call_rcu()
+ * will be processed in a timely fashion.
+ */
+void rcu_async_hurry(void)
+{
+	if (IS_ENABLED(CONFIG_RCU_LAZY))
+		atomic_inc(&rcu_async_hurry_nesting);
+}
+EXPORT_SYMBOL_GPL(rcu_async_hurry);
 
+/**
+ * rcu_async_relax - Make future async RCU callbacks lazy.
+ *
+ * After a call to this function, future calls to call_rcu()
+ * will be processed in a lazy fashion.
+ */
+void rcu_async_relax(void)
+{
+	if (IS_ENABLED(CONFIG_RCU_LAZY))
+		atomic_dec(&rcu_async_hurry_nesting);
+}
+EXPORT_SYMBOL_GPL(rcu_async_relax);
+
+static atomic_t rcu_expedited_nesting = ATOMIC_INIT(1);
 /*
  * Should normal grace-period primitives be expedited?  Intended for
  * use within RCU.  Note that this function takes the rcu_expedited
@@ -195,6 +232,7 @@ static bool rcu_boot_ended __read_mostly;
 void rcu_end_inkernel_boot(void)
 {
 	rcu_unexpedite_gp();
+	rcu_async_relax();
 	if (rcu_normal_after_boot)
 		WRITE_ONCE(rcu_normal, 1);
 	rcu_boot_ended = true;
@@ -220,6 +258,7 @@ void rcu_test_sync_prims(void)
 {
 	if (!IS_ENABLED(CONFIG_PROVE_RCU))
 		return;
+	pr_info("Running RCU synchronous self tests\n");
 	synchronize_rcu();
 	synchronize_rcu_expedited();
 }
@@ -508,6 +547,8 @@ int rcu_cpu_stall_timeout __read_mostly = CONFIG_RCU_CPU_STALL_TIMEOUT;
 module_param(rcu_cpu_stall_timeout, int, 0644);
 int rcu_exp_cpu_stall_timeout __read_mostly = CONFIG_RCU_EXP_CPU_STALL_TIMEOUT;
 module_param(rcu_exp_cpu_stall_timeout, int, 0644);
+bool rcu_exp_stall_task_details __read_mostly;
+module_param(rcu_exp_stall_task_details, bool, 0644);
 #endif /* #ifdef CONFIG_RCU_STALL_COMMON */
 
 // Suppress boot-time RCU CPU stall warnings and rcutorture writer stall
@@ -555,9 +596,12 @@ struct early_boot_kfree_rcu {
 static void early_boot_test_call_rcu(void)
 {
 	static struct rcu_head head;
+	int idx;
 	static struct rcu_head shead;
 	struct early_boot_kfree_rcu *rhp;
 
+	idx = srcu_down_read(&early_srcu);
+	srcu_up_read(&early_srcu, idx);
 	call_rcu(&head, test_callback);
 	early_srcu_cookie = start_poll_synchronize_srcu(&early_srcu);
 	call_srcu(&early_srcu, &shead, test_callback);
@@ -586,6 +630,7 @@ static int rcu_verify_early_boot_tests(void)
 		early_boot_test_counter++;
 		srcu_barrier(&early_srcu);
 		WARN_ON_ONCE(!poll_state_synchronize_srcu(&early_srcu, early_srcu_cookie));
+		cleanup_srcu_struct(&early_srcu);
 	}
 	if (rcu_self_test_counter != early_boot_test_counter) {
 		WARN_ON(1);