Re: [PATCH v2] x86/trace: set TRACE_INCLUDE_PATH correctly instead of header search path

[Steven Rostedt]

On Mon, Dec 31, 2018 at 12:23:25AM +0900, Masahiro Yamada wrote:
> ---
> 
> Changes in v2:
>   - Rebase
> 
>  arch/x86/include/asm/trace/exceptions.h  | 2 +-
>  arch/x86/include/asm/trace/irq_vectors.h | 2 +-
>  arch/x86/kernel/Makefile                 | 2 --
>  arch/x86/mm/Makefile                     | 2 --
>  4 files changed, 2 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/x86/include/asm/trace/exceptions.h b/arch/x86/include/asm/trace/exceptions.h
> index e0e6d7f..00c1d1b 100644
> --- a/arch/x86/include/asm/trace/exceptions.h
> +++ b/arch/x86/include/asm/trace/exceptions.h
> @@ -46,7 +46,7 @@ DEFINE_PAGE_FAULT_EVENT(page_fault_kernel);
>  
>  #undef TRACE_INCLUDE_PATH
>  #undef TRACE_INCLUDE_FILE
> -#define TRACE_INCLUDE_PATH .
> +#define TRACE_INCLUDE_PATH asm/trace/

As I replied in another thread:

Note, the reason why I did not show this method in the samples/trace_events/
is that there's one "gotcha" that you need to be careful about. It may not be
an issue here, but please be aware of it.

The words in TRACE_INCLUDE_PATH can be updated by C preprocessor defines. For
example, if for some reason you had:

#define asm special_asm

The above would turn into:

#define TRACE_INCLUDE_PATH special_asm/trace

 and it wont build, and you will be left scratching your head wondering why.

Again, it most likely wont be an issue, but perhaps a comment or something
should be noted to warn about it?

-- Steve


>  #define TRACE_INCLUDE_FILE exceptions
>  #endif /*  _TRACE_PAGE_FAULT_H */