/*
* rcuwait provides a way of blocking and waking up a single
- * task in an rcu-safe manner; where it is forbidden to use
- * after exit_notify(). task_struct is not properly rcu protected,
- * unless dealing with rcu-aware lists, ie: find_task_by_*().
+ * task in an rcu-safe manner.
*
- * Alternatively we have task_rcu_dereference(), but the return
- * semantics have different implications which would break the
- * wakeup side. The only time @task is non-nil is when a user is
- * blocked (or checking if it needs to) on a condition, and reset
- * as soon as we know that the condition has succeeded and are
- * awoken.
+ * The only time @task is non-nil is when a user is blocked (or
+ * checking if it needs to) on a condition, and reset as soon as we
+ * know that the condition has succeeded and are awoken.
*/
struct rcuwait {
struct task_struct __rcu *task;
*/
#define rcuwait_wait_event(w, condition) \
({ \
- /* \
- * Complain if we are called after do_exit()/exit_notify(), \
- * as we cannot rely on the rcu critical region for the \
- * wakeup side. \
- */ \
- WARN_ON(current->exit_state); \
- \
rcu_assign_pointer((w)->task, current); \
for (;;) { \
/* \