- * ZTHR wakeup, cancel, and resume are requests on a zthr to
- * change its internal state. Requests on a zthr are serialized
- * using the zthr_request_lock, while changes in its internal
- * state are protected by the zthr_state_lock. A request will
- * first acquire the zthr_request_lock and then immediately
- * acquire the zthr_state_lock. We do this so that incoming
- * requests are serialized using the request lock, while still
- * allowing us to use the state lock for thread communication
- * via zthr_cv.
+ * ZTHR cancel and resume are requests on a zthr to change its
+ * internal state. These requests are serialized using the
+ * zthr_request_lock, while changes in its internal state are
+ * protected by the zthr_state_lock. A request will first acquire
+ * the zthr_request_lock and then immediately acquire the
+ * zthr_state_lock. We do this so that incoming requests are
+ * serialized using the request lock, while still allowing us
+ * to use the state lock for thread communication via zthr_cv.
+ *
+ * ZTHR wakeup broadcasts to zthr_cv, causing sleeping threads
+ * to wakeup. It acquires the zthr_state_lock but not the
+ * zthr_request_lock, so that a wakeup on a zthr in the middle
+ * of being cancelled will not block.