X-Git-Url: http://git.lttng.org/?p=userspace-rcu.git;a=blobdiff_plain;f=README;h=0ec723dea10186d13e6c11705e18a0c8149ae288;hp=ae8b6619cb5645dfcab48f3bf96d257b20b42973;hb=cee02f0ab0a6766662490f2d815d487c098c17b1;hpb=5f373c844a426494807d41d6fd3482649f3dc400

diff --git a/README b/README
index ae8b661..0ec723d 100644
--- a/README
+++ b/README
@@ -39,11 +39,20 @@ Being careful with signals
 	signal(7). To ensure the Userspace RCU library does not use signals,
 	define CONFIG_URCU_AVOID_SIGNALS at compile-time.
 
+	Read-side critical sections can sit in a signal handler. Be careful,
+	however, to disable these signals between thread creation and calls to
+	rcu_register_thread(), because a signal handler nesting on an
+	unregistered thread would not be allowed to call rcu_read_lock().
+
 Usage of CONFIG_URCU_AVOID_SIGNALS
 
 	CONFIG_URCU_AVOID_SIGNALS uses full SMP barriers for readers. This
 	eliminates the need for signals but results in slower reads.
 
+Usage of DEBUG_RCU
+
+	DEBUG_RCU is used to add internal debugging self-checks to the
+	RCU library. This define adds a performance penality when enabled.
 
 Usage of DEBUG_YIELD