diff options
Diffstat (limited to 'kernel/rcu')
| -rw-r--r-- | kernel/rcu/tree.c | 24 |
1 files changed, 14 insertions, 10 deletions
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 2437960a2795..4b00e4fbfa10 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -3059,12 +3059,14 @@ __call_rcu(struct rcu_head *head, rcu_callback_t func) * period elapses, in other words after all pre-existing RCU read-side * critical sections have completed. However, the callback function * might well execute concurrently with RCU read-side critical sections - * that started after call_rcu() was invoked. RCU read-side critical - * sections are delimited by rcu_read_lock() and rcu_read_unlock(), and - * may be nested. In addition, regions of code across which interrupts, - * preemption, or softirqs have been disabled also serve as RCU read-side - * critical sections. This includes hardware interrupt handlers, softirq - * handlers, and NMI handlers. + * that started after call_rcu() was invoked. + * + * RCU read-side critical sections are delimited by rcu_read_lock() + * and rcu_read_unlock(), and may be nested. In addition, but only in + * v5.0 and later, regions of code across which interrupts, preemption, + * or softirqs have been disabled also serve as RCU read-side critical + * sections. This includes hardware interrupt handlers, softirq handlers, + * and NMI handlers. * * Note that all CPUs must agree that the grace period extended beyond * all pre-existing RCU read-side critical section. On systems with more @@ -3730,10 +3732,12 @@ static int rcu_blocking_is_gp(void) * read-side critical sections have completed. Note, however, that * upon return from synchronize_rcu(), the caller might well be executing * concurrently with new RCU read-side critical sections that began while - * synchronize_rcu() was waiting. RCU read-side critical sections are - * delimited by rcu_read_lock() and rcu_read_unlock(), and may be nested. - * In addition, regions of code across which interrupts, preemption, or - * softirqs have been disabled also serve as RCU read-side critical + * synchronize_rcu() was waiting. + * + * RCU read-side critical sections are delimited by rcu_read_lock() + * and rcu_read_unlock(), and may be nested. In addition, but only in + * v5.0 and later, regions of code across which interrupts, preemption, + * or softirqs have been disabled also serve as RCU read-side critical * sections. This includes hardware interrupt handlers, softirq handlers, * and NMI handlers. * |