[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH for-5.1] tracetool: carefully define SDT_USE_VARIADIC
From: |
Philippe Mathieu-Daudé |
Subject: |
Re: [PATCH for-5.1] tracetool: carefully define SDT_USE_VARIADIC |
Date: |
Thu, 30 Jul 2020 18:16:48 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 |
On 7/29/20 5:39 PM, Stefan Hajnoczi wrote:
> The dtrace backend defines SDT_USE_VARIADIC as a workaround for a
> conflict with a LTTng UST header file, which requires SDT_USE_VARIADIC
> to be defined.
>
> LTTng UST <lttng/tracepoint.h> breaks if included after generated dtrace
> headers because SDT_USE_VARIADIC will already be defined:
>
> #ifdef LTTNG_UST_HAVE_SDT_INTEGRATION
> #define SDT_USE_VARIADIC <-- error, it's already defined
> #include <sys/sdt.h>
>
> Be more careful when defining SDT_USE_VARIADIC. This fixes the build
> when both the dtrace and ust tracers are enabled at the same time.
>
> Fixes: 27e08bab94f7c6ebe0b75938c98c394c969e3fd8 ("tracetool: work around ust
> <sys/sdt.h> include conflict")
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
> scripts/tracetool/backend/dtrace.py | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/scripts/tracetool/backend/dtrace.py
> b/scripts/tracetool/backend/dtrace.py
> index b7fe4c1b50..fc0c8fc52f 100644
> --- a/scripts/tracetool/backend/dtrace.py
> +++ b/scripts/tracetool/backend/dtrace.py
> @@ -44,11 +44,15 @@ def generate_h_begin(events, group):
> # require SDT_USE_VARIADIC to be defined. If dtrace includes <sys/sdt.h>
> # first without defining SDT_USE_VARIADIC then ust breaks because the
> # STAP_PROBEV() macro is not defined.
> + out('#ifndef SDT_USE_VARIADIC')
> out('#define SDT_USE_VARIADIC 1')
> + out('#endif')
>
> out('#include "%s"' % header,
> '')
>
> + out('#undef SDT_USE_VARIADIC')
> +
> # SystemTap defines <provider>_<name>_ENABLED() but other DTrace
> # implementations might not.
> for e in events:
>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>