Re: [PATCH] perf build: Suppress warning about missing libbabeltrace

[Ingo Molnar <mingo@kernel.org>]

* Jiri Olsa <jolsa@kernel.org> wrote:

> Be silent about missing babeltrace library until the needed
> version (1.3) is pushed into most common distros.
> 
> Requested-by: Ingo Molnar <mingo@kernel.org>
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> Link: http://lkml.kernel.org/n/tip-95mcd8hoxyt43jighilggjej@git.kernel.org
> ---
>  tools/perf/config/Makefile | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile
> index cd121dfc4de9..2d9142b10cd3 100644
> --- a/tools/perf/config/Makefile
> +++ b/tools/perf/config/Makefile
> @@ -606,7 +606,12 @@ ifndef NO_LIBBABELTRACE
>      EXTLIBS += -lbabeltrace-ctf
>      $(call detected,CONFIG_LIBBABELTRACE)
>    else
> -    msg := $(warning No libbabeltrace found, disables 'perf data' CTF format support, please install libbabeltrace-dev[el]/libbabeltrace-ctf-dev);
> +#
> +# Be silent about missing babeltrace library
> +# until the needed version (1.3) is pushed
> +# into most common distros.
> +#
> +#    msg := $(warning No libbabeltrace found, disables 'perf data' CTF format support, please install libbabeltrace-dev[el]/libbabeltrace-ctf-dev);
>      NO_LIBBABELTRACE := 1
>    endif
>  endif

But, but ... the feature detection is still executed, and it slows 
down the regular build on 99.9999% of the systems, right?

I don't mind carrying the code, but could we make it such that it 
needs some special option to build or so?

Thanks,

	Ingo