diff options
Diffstat (limited to 'kernel/rcutree_plugin.h')
| -rw-r--r-- | kernel/rcutree_plugin.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index f92115488187..57e0ef8ed721 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -670,6 +670,9 @@ EXPORT_SYMBOL_GPL(kfree_call_rcu); * 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. + * + * See the description of synchronize_sched() for more detailed information + * on memory ordering guarantees. */ void synchronize_rcu(void) { @@ -875,6 +878,11 @@ EXPORT_SYMBOL_GPL(synchronize_rcu_expedited); /** * rcu_barrier - Wait until all in-flight call_rcu() callbacks complete. + * + * Note that this primitive does not necessarily wait for an RCU grace period + * to complete. For example, if there are no RCU callbacks queued anywhere + * in the system, then rcu_barrier() is within its rights to return + * immediately, without waiting for anything, much less an RCU grace period. */ void rcu_barrier(void) { |