linux/include/trace/define_custom_trace.h
Steven Rostedt (Google) 3a73333fb3 tracing: Add TRACE_CUSTOM_EVENT() macro
To make it really easy to add custom events from modules, add a
TRACE_CUSTOM_EVENT() macro that acts just like the TRACE_EVENT() macro,
but creates a custom event to an already existing tracepoint.

The trace_custom_sched.[ch] has been updated to use this new macro to show
how simple it is.

Link: https://lkml.kernel.org/r/20220303220625.738622494@goodmis.org

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-11 11:49:24 -05:00

78 lines
2.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Trace files that want to automate creation of all tracepoints defined
* in their file should include this file. The following are macros that the
* trace file may define:
*
* TRACE_SYSTEM defines the system the tracepoint is for
*
* TRACE_INCLUDE_FILE if the file name is something other than TRACE_SYSTEM.h
* This macro may be defined to tell define_trace.h what file to include.
* Note, leave off the ".h".
*
* TRACE_INCLUDE_PATH if the path is something other than core kernel include/trace
* then this macro can define the path to use. Note, the path is relative to
* define_trace.h, not the file including it. Full path names for out of tree
* modules must be used.
*/
#ifdef CREATE_CUSTOM_TRACE_EVENTS
/* Prevent recursion */
#undef CREATE_CUSTOM_TRACE_EVENTS
#include <linux/stringify.h>
#undef TRACE_CUSTOM_EVENT
#define TRACE_CUSTOM_EVENT(name, proto, args, tstruct, assign, print)
#undef DEFINE_CUSTOM_EVENT
#define DEFINE_CUSTOM_EVENT(template, name, proto, args)
#undef TRACE_INCLUDE
#undef __TRACE_INCLUDE
#ifndef TRACE_INCLUDE_FILE
# define TRACE_INCLUDE_FILE TRACE_SYSTEM
# define UNDEF_TRACE_INCLUDE_FILE
#endif
#ifndef TRACE_INCLUDE_PATH
# define __TRACE_INCLUDE(system) <trace/events/system.h>
# define UNDEF_TRACE_INCLUDE_PATH
#else
# define __TRACE_INCLUDE(system) __stringify(TRACE_INCLUDE_PATH/system.h)
#endif
# define TRACE_INCLUDE(system) __TRACE_INCLUDE(system)
/* Let the trace headers be reread */
#define TRACE_CUSTOM_MULTI_READ
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
#ifdef TRACEPOINTS_ENABLED
#include <trace/trace_custom_events.h>
#endif
#undef TRACE_CUSTOM_EVENT
#undef DECLARE_CUSTOM_EVENT_CLASS
#undef DEFINE_CUSTOM_EVENT
#undef TRACE_CUSTOM_MULTI_READ
/* Only undef what we defined in this file */
#ifdef UNDEF_TRACE_INCLUDE_FILE
# undef TRACE_INCLUDE_FILE
# undef UNDEF_TRACE_INCLUDE_FILE
#endif
#ifdef UNDEF_TRACE_INCLUDE_PATH
# undef TRACE_INCLUDE_PATH
# undef UNDEF_TRACE_INCLUDE_PATH
#endif
/* We may be processing more files */
#define CREATE_CUSTOM_TRACE_POINTS
#endif /* CREATE_CUSTOM_TRACE_POINTS */