Function rrw_exit

freebsd/contrib/openzfs/module/zfs/rrwlock.c:239–276

}

void
rrw_exit(rrwlock_t *rrl, void *tag)
{
	mutex_enter(&rrl->rr_lock);
#if !defined(ZFS_DEBUG) && defined(_KERNEL)
	if (!rrl->rr_writer && rrl->rr_linked_rcount.rc_count == 0) {
		rrl->rr_anon_rcount.rc_count--;
		if (rrl->rr_anon_rcount.rc_count == 0)
			cv_broadcast(&rrl->rr_cv);
		mutex_exit(&rrl->rr_lock);
		return;
	}
	DTRACE_PROBE(zfs__rrwfastpath__exitmiss);
#endif
	ASSERT(!zfs_refcount_is_zero(&rrl->rr_anon_rcount) ||
	    !zfs_refcount_is_zero(&rrl->rr_linked_rcount) ||
	    rrl->rr_writer != NULL);

	if (rrl->rr_writer == NULL) {
		int64_t count;
		if (rrn_find_and_remove(rrl, tag)) {
			count = zfs_refcount_remove(
			    &rrl->rr_linked_rcount, tag);
		} else {
			ASSERT(!rrl->rr_track_all);
			count = zfs_refcount_remove(&rrl->rr_anon_rcount, tag);
		}
		if (count == 0)
			cv_broadcast(&rrl->rr_cv);
	} else {
		ASSERT(rrl->rr_writer == curthread);
		ASSERT(zfs_refcount_is_zero(&rrl->rr_anon_rcount) &&
		    zfs_refcount_is_zero(&rrl->rr_linked_rcount));
		rrl->rr_writer = NULL;
		cv_broadcast(&rrl->rr_cv);
	}
	mutex_exit(&rrl->rr_lock);
}

/*
 * If the lock was created with track_all, rrw_held(RW_READER) will return