+Usage of urcu-call-rcu
+
+ * Follow instructions for either liburcu, liburcu-qsbr,
+ liburcu-mb, liburcu-signal, or liburcu-bp above.
+ The urcu-call-rcu functionality is provided for each of
+ these library modules.
+ * Provides the call_rcu() primitive to enqueue delayed callbacks
+ in a manner similar to defer_rcu(), but without ever delaying
+ for a grace period. On the other hand, call_rcu()'s best-case
+ overhead is not quite as good as that of defer_rcu().
+ * Provides call_rcu() to allow asynchronous handling of RCU
+ grace periods. A number of additional functions are provided
+ to manage the helper threads used by call_rcu(), but reasonable
+ defaults are used if these additional functions are not invoked.
+ See API.txt for more details.
+