tracing: update sample event documentation

[safe/jmp/linux-2.6] / samples / trace_events / Makefile

diff --git a/samples/trace_events/Makefile b/samples/trace_events/Makefile
index 0d428dc..0f8d921 100644 (file)
--- a/samples/trace_events/Makefile
+++ b/samples/trace_events/Makefile
@@ -1,6 +1,14 @@
 # builds the trace events example kernel modules;
 # then to use one (as root):  insmod <module_name.ko>
 
+# If you include a trace header outside of include/trace/events
+# then the file that does the #define CREATE_TRACE_POINTS must
+# have that tracer file in its main search path. This is because
+# define_trace.h will include it, and must be able to find it from
+# the include/trace directory.
+#
+# Here trace-events-sample.c does the CREATE_TRACE_POINTS.
+#
 CFLAGS_trace-events-sample.o := -I$(src)
 
 obj-$(CONFIG_SAMPLE_TRACE_EVENTS) += trace-events-sample.o