From: Jeremy Linton Perf has a problem that if sizeof() macros are used within TRACE_EVENT() macro's they end up in userspace as "sizeof(kernel structure)" which cannot properly be parsed. Add a macro which can forward this data through the eval_map for userspace utilization. Link: http://lkml.kernel.org/r/20170531215653.3240-10-jeremy.linton@arm.com Signed-off-by: Jeremy Linton Signed-off-by: Steven Rostedt (VMware) --- include/linux/tracepoint.h | 1 + include/trace/trace_events.h | 16 ++++++++++++++++ 2 files changed, 17 insertions(+) diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index f7b0f5525e46..a26ffbe09e71 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -88,6 +88,7 @@ extern void syscall_unregfunc(void); #define PARAMS(args...) args #define TRACE_DEFINE_ENUM(x) +#define TRACE_DEFINE_SIZEOF(x) #endif /* _LINUX_TRACEPOINT_H */ diff --git a/include/trace/trace_events.h b/include/trace/trace_events.h index 49cce5fb54ee..3976fa1f6e42 100644 --- a/include/trace/trace_events.h +++ b/include/trace/trace_events.h @@ -46,6 +46,19 @@ TRACE_MAKE_SYSTEM_STR(); __attribute__((section("_ftrace_eval_map"))) \ *TRACE_SYSTEM##_##a = &__##TRACE_SYSTEM##_##a +#undef TRACE_DEFINE_SIZEOF +#define TRACE_DEFINE_SIZEOF(a) \ + static struct trace_eval_map __used __initdata \ + __##TRACE_SYSTEM##_##a = \ + { \ + .system = TRACE_SYSTEM_STRING, \ + .eval_string = "sizeof(" #a ")", \ + .eval_value = sizeof(a) \ + }; \ + static struct trace_eval_map __used \ + __attribute__((section("_ftrace_eval_map"))) \ + *TRACE_SYSTEM##_##a = &__##TRACE_SYSTEM##_##a + /* * DECLARE_EVENT_CLASS can be used to add a generic function * handlers for events. That is, if all events have the same @@ -158,6 +171,9 @@ TRACE_MAKE_SYSTEM_STR(); #undef TRACE_DEFINE_ENUM #define TRACE_DEFINE_ENUM(a) +#undef TRACE_DEFINE_SIZEOF +#define TRACE_DEFINE_SIZEOF(a) + #undef __field #define __field(type, item) -- 2.10.2