diff --git a/Documentation/ABI/testing/sysfs-bus-event_source-devices-events b/Documentation/ABI/testing/sysfs-bus-event_source-devices-events
index 20979f8b3edb..505f080d20a1 100644
--- a/Documentation/ABI/testing/sysfs-bus-event_source-devices-events
+++ b/Documentation/ABI/testing/sysfs-bus-event_source-devices-events
@@ -52,12 +52,18 @@ Description:	Per-pmu performance monitoring events specific to the running syste
 			event=0x2abc
 			event=0x423,inv,cmask=0x3
 			domain=0x1,offset=0x8,starting_index=0xffff
+			domain=0x1,offset=0x8,core=?
 
 		Each of the assignments indicates a value to be assigned to a
 		particular set of bits (as defined by the format file
 		corresponding to the <term>) in the perf_event structure passed
 		to the perf_open syscall.
 
+		In the case of the last example, a value replacing "?" would
+		need to be provided by the user selecting the particular event.
+		This is referred to as "event parameterization". Event
+		parameters have the format 'param=?'.
+
 What: /sys/bus/event_source/devices/<pmu>/events/<event>.unit
 Date: 2014/02/24
 Contact:	Linux kernel mailing list <linux-kernel@vger.kernel.org>