From c94fbe1d9e1e9b1a1f82eb0b53b1cf53bcf9712b Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Fri, 14 Jan 2011 11:25:58 -0500 Subject: tracing: Only process module tracepoints once The commit: 9f987b3141f086de27832514aad9f50a53f754 tracing: Include module.h in define_trace.h only solved half the problem. If the trace/events/module.h header is included at the time of define_trace.h (or in ftrace.h within it), the module.h TRACE_SYSTEM will override the current TRACE_SYSTEM macro. Since define_trace.h is included when CREATE_TRACE_POINTS is set, and the first thing it does is to #undef CREATE_TRACE_POINTS, by placing the module.h TRACE_SYSTEM inside a #ifdef CREATE_TRACE_POINTS we can prevent it from overriding the TRACE_SYSTEM that is being processed, and still process the module.h tracepoints when the module code defines CREATE_TRACE_POINTS and includes the trace/events/module.h header. As with commit 9f987b3141, this is only an issue if module.h is not included before the trace/events/.h file is included, which (luckily) has not happened yet. Reported-by: Peter Zijlstra Signed-off-by: Steven Rostedt --- include/trace/events/module.h | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/include/trace/events/module.h b/include/trace/events/module.h index c7bb2f0..c6bae36 100644 --- a/include/trace/events/module.h +++ b/include/trace/events/module.h @@ -1,5 +1,15 @@ +/* + * Because linux/module.h has tracepoints in the header, and ftrace.h + * eventually includes this file, define_trace.h includes linux/module.h + * But we do not want the module.h to override the TRACE_SYSTEM macro + * variable that define_trace.h is processing, so we only set it + * when module events are being processed, which would happen when + * CREATE_TRACE_POINTS is defined. + */ +#ifdef CREATE_TRACE_POINTS #undef TRACE_SYSTEM #define TRACE_SYSTEM module +#endif #if !defined(_TRACE_MODULE_H) || defined(TRACE_HEADER_MULTI_READ) #define _TRACE_MODULE_H -- cgit v1.1