doc: Update RCU documentation

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/Documentation/RCU/whatisRCU.txt b/Documentation/RCU/whatisRCU.txt
index 8ed6c9f6133c..df62466da4e0 100644
--- a/Documentation/RCU/whatisRCU.txt
+++ b/Documentation/RCU/whatisRCU.txt
@@ -890,6 +890,8 @@ SRCU:	Critical sections	Grace period		Barrier
 	srcu_read_lock_held
 
 SRCU:	Initialization/cleanup
+	DEFINE_SRCU
+	DEFINE_STATIC_SRCU
 	init_srcu_struct
 	cleanup_srcu_struct
 
@@ -913,7 +915,8 @@ a.	Will readers need to block?  If so, you need SRCU.
 b.	What about the -rt patchset?  If readers would need to block
 	in an non-rt kernel, you need SRCU.  If readers would block
 	in a -rt kernel, but not in a non-rt kernel, SRCU is not
-	necessary.
+	necessary.  (The -rt patchset turns spinlocks into sleeplocks,
+	hence this distinction.)
 
 c.	Do you need to treat NMI handlers, hardirq handlers,
 	and code segments with preemption disabled (whether