| Message ID | 20200729153926.127083-1-stefanha@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | [for-5.1] tracetool: carefully define SDT_USE_VARIADIC | expand |
On Wed, Jul 29, 2020 at 04:39:26PM +0100, 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(+) Thanks, applied to my tracing tree: https://github.com/stefanha/qemu/commits/tracing Stefan
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>
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:
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(+)