diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index a13d69b..8ae5fac 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1444,7 +1444,8 @@
 			Param: "schedule" - profile schedule points.
 			Param: <number> - step/bucket size as a power of 2 for
 				statistical time based profiling.
-			Param: "sleep" - profile D-state sleeping (millisecs)
+			Param: "sleep" - profile D-state sleeping (millisecs).
+				Requires CONFIG_SCHEDSTATS
 			Param: "kvm" - profile VM exits.
 
 	processor.max_cstate=	[HW,ACPI]