mirror of
https://github.com/adulau/aha.git
synced 2024-12-27 11:16:11 +00:00
tracing: update sample event documentation
The comments in the sample code is a bit confusing. This patch cleans them up a little. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
parent
00e95830a4
commit
44ad18e0a6
2 changed files with 24 additions and 11 deletions
|
@ -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
|
||||
|
|
|
@ -19,16 +19,21 @@
|
|||
* If TRACE_SYSTEM is defined, that will be the directory created
|
||||
* in the ftrace directory under /debugfs/tracing/events/<system>
|
||||
*
|
||||
* The define_trace.h belowe will also look for a file name of
|
||||
* 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
|
||||
*
|
||||
* If you want a different system than file name, you can override
|
||||
* the header name by defining TRACE_INCLUDE_FILE
|
||||
* 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
|
||||
*
|
||||
* If this file was called, goofy.h, then we would define:
|
||||
* 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
|
||||
* file:
|
||||
*
|
||||
* #define TRACE_INCLUDE_FILE goofy
|
||||
* #define TRACE_INCLUDE_FILE trace-events-sample
|
||||
*
|
||||
* As we do an the bottom of this file.
|
||||
*/
|
||||
#undef TRACE_SYSTEM
|
||||
#define TRACE_SYSTEM sample
|
||||
|
@ -99,13 +104,13 @@ TRACE_EVENT(foo_bar,
|
|||
*
|
||||
* #define TRACE_INCLUDE_PATH ../../samples/trace_events
|
||||
*
|
||||
* But I chose to simply make it use the current directory and then in
|
||||
* the Makefile I added:
|
||||
* But the safest and easiest way to simply make it use the directory
|
||||
* that the file is in is to add in the Makefile:
|
||||
*
|
||||
* CFLAGS_trace-events-sample.o := -I$(PWD)/samples/trace_events/
|
||||
* CFLAGS_trace-events-sample.o := -I$(src)
|
||||
*
|
||||
* This will make sure the current path is part of the include
|
||||
* structure for our file so that we can find it.
|
||||
* structure for our file so that define_trace.h can find it.
|
||||
*
|
||||
* I could have made only the top level directory the include:
|
||||
*
|
||||
|
@ -115,8 +120,8 @@ TRACE_EVENT(foo_bar,
|
|||
*
|
||||
* #define TRACE_INCLUDE_PATH samples/trace_events
|
||||
*
|
||||
* But then if something defines "samples" or "trace_events" then we
|
||||
* could risk that being converted too, and give us an unexpected
|
||||
* But then if something defines "samples" or "trace_events" as a macro
|
||||
* then we could risk that being converted too, and give us an unexpected
|
||||
* result.
|
||||
*/
|
||||
#undef TRACE_INCLUDE_PATH
|
||||
|
|
Loading…
Reference in a new issue