On Sun, 2011-01-09 at 21:09 +0000, tip-bot for Steven Rostedt wrote: > Commit-ID: 3a9f987b3141f086de27832514aad9f50a53f754 > Gitweb: http://git.kernel.org/tip/3a9f987b3141f086de27832514aad9f50a53f754 > Author: Steven Rostedt <srostedt@xxxxxxxxxx> > AuthorDate: Fri, 7 Jan 2011 15:40:10 -0500 > Committer: Steven Rostedt <rostedt@xxxxxxxxxxx> > CommitDate: Fri, 7 Jan 2011 15:44:56 -0500 > > tracing: Include module.h in define_trace.h > > While doing some developing, Peter Zijlstra and I have found > that if a CREATE_TRACE_POINTS include is done before module.h > is included, it can break the build. > > We have been lucky so far that this has not broke the build > since module.h is included in almost everything. > > Reported-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> > Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx> > --- > include/trace/define_trace.h | 10 ++++++++++ > 1 files changed, 10 insertions(+), 0 deletions(-) > > diff --git a/include/trace/define_trace.h b/include/trace/define_trace.h > index b0b4eb2..da39b22 100644 > --- a/include/trace/define_trace.h > +++ b/include/trace/define_trace.h > @@ -21,6 +21,16 @@ > #undef CREATE_TRACE_POINTS > > #include <linux/stringify.h> > +/* > + * module.h includes tracepoints, and because ftrace.h > + * pulls in module.h: > + * trace/ftrace.h -> linux/ftrace_event.h -> linux/perf_event.h -> > + * linux/ftrace.h -> linux/module.h > + * we must include module.h here before we play with any of > + * the TRACE_EVENT() macros, otherwise the tracepoints included > + * by module.h may break the build. > + */ > +#include <linux/module.h> > > #undef TRACE_EVENT > #define TRACE_EVENT(name, proto, args, tstruct, assign, print) \ After I got everything building on that tree I was working on, the above was found to compile but not to link, since it makes every: #define CREATE_TRACE_POINTS #include <trace/event/foo.h> site also create the trace/event/module.h tracepoints, thus confusing the linker with tons of duplicate symbols. The below patch makes things compile and link: --- include/trace/define_trace.h | 23 +++++++++++++---------- 1 files changed, 13 insertions(+), 10 deletions(-) diff --git a/include/trace/define_trace.h b/include/trace/define_trace.h index da39b22..9ebd0d3 100644 --- a/include/trace/define_trace.h +++ b/include/trace/define_trace.h @@ -21,16 +21,6 @@ #undef CREATE_TRACE_POINTS #include <linux/stringify.h> -/* - * module.h includes tracepoints, and because ftrace.h - * pulls in module.h: - * trace/ftrace.h -> linux/ftrace_event.h -> linux/perf_event.h -> - * linux/ftrace.h -> linux/module.h - * we must include module.h here before we play with any of - * the TRACE_EVENT() macros, otherwise the tracepoints included - * by module.h may break the build. - */ -#include <linux/module.h> #undef TRACE_EVENT #define TRACE_EVENT(name, proto, args, tstruct, assign, print) \ @@ -120,4 +110,17 @@ /* We may be processing more files */ #define CREATE_TRACE_POINTS +#else /* CREATE_TRACE_POINTS */ + +/* + * module.h includes tracepoints, and because ftrace.h + * pulls in module.h: + * trace/ftrace.h -> linux/ftrace_event.h -> linux/perf_event.h -> + * linux/ftrace.h -> linux/module.h + * we must include module.h here before we play with any of + * the TRACE_EVENT() macros, otherwise the tracepoints included + * by module.h may break the build. + */ +#include <linux/module.h> + #endif /* CREATE_TRACE_POINTS */ -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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