This patch contains the PCM utility installation and continously

[kvmfornfv.git] / kernel / samples / trace_events / trace-events-sample.h

diff --git a/kernel/samples/trace_events/trace-events-sample.h b/kernel/samples/trace_events/trace-events-sample.h
index 8965d1b..d6b75bb 100644 (file)
--- a/kernel/samples/trace_events/trace-events-sample.h
+++ b/kernel/samples/trace_events/trace-events-sample.h
@@ -4,14 +4,14 @@
  *
  * The define_trace.h below will also look for a file name of
  * TRACE_SYSTEM.h where TRACE_SYSTEM is what is defined here.
- * In this case, it would look for sample.h
+ * In this case, it would look for sample-trace.h
  *
  * If the header name will be different than the system name
  * (as in this case), then you can override the header name that
  * define_trace.h will look up by defining TRACE_INCLUDE_FILE
  *
  * This file is called trace-events-sample.h but we want the system
- * to be called "sample". Therefore we must define the name of this
+ * to be called "sample-trace". Therefore we must define the name of this
  * file:
  *
  * #define TRACE_INCLUDE_FILE trace-events-sample
@@ -106,7 +106,7 @@
  *
  *         memcpy(__entry->foo, bar, 10);
  *
- *   __dynamic_array: This is similar to array, but can vary is size from
+ *   __dynamic_array: This is similar to array, but can vary its size from
  *         instance to instance of the tracepoint being called.
  *         Like __array, this too has three elements (type, name, size);
  *         type is the type of the element, name is the name of the array.
@@ -168,7 +168,10 @@
  *
  *      For __dynamic_array(int, foo, bar) use __get_dynamic_array(foo)
  *            Use __get_dynamic_array_len(foo) to get the length of the array
- *            saved.
+ *            saved. Note, __get_dynamic_array_len() returns the total allocated
+ *            length of the dynamic array; __print_array() expects the second
+ *            parameter to be the number of elements. To get that, the array length
+ *            needs to be divided by the element size.
  *
  *      For __string(foo, bar) use __get_str(foo)
  *
@@ -288,7 +291,7 @@ TRACE_EVENT(foo_bar,
  *    This prints out the array that is defined by __array in a nice format.
  */
                  __print_array(__get_dynamic_array(list),
-                               __get_dynamic_array_len(list),
+                               __get_dynamic_array_len(list) / sizeof(int),
                                sizeof(int)),
                  __get_str(str), __get_bitmask(cpus))
 );