Re: [Qemu-devel] [PATCH v2 01/47] trace: introduce some Makefile rules for module code gen

["Daniel P. Berrange" <berrange@redhat.com>]

On Fri, Jan 06, 2017 at 06:20:51PM +0100, Lluís Vilanova wrote:
> Daniel P Berrange writes:
> 
> > Introduce rules that are able to generate trace.[ch] files
> > in every subdirectory which has a trace-events file.
> 
> > Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
> > ---
> >  .gitignore                               |  6 +++
> >  Makefile                                 | 65 +++++++++++++++++++++++++++-----
> >  Makefile.objs                            |  5 +++
> >  Makefile.target                          |  7 +++-
> >  scripts/tracetool/backend/dtrace.py      |  7 +++-
> >  scripts/tracetool/backend/ust.py         |  7 +++-
> >  scripts/tracetool/format/ust_events_c.py |  2 +-
> >  scripts/tracetool/format/ust_events_h.py |  7 +++-
> >  tests/Makefile.include                   |  2 +-
> >  trace/Makefile.objs                      | 23 ++++++++---
> >  10 files changed, 109 insertions(+), 22 deletions(-)
> 
> > diff --git a/.gitignore b/.gitignore
> > index e43c304..fe6add3 100644
> > --- a/.gitignore
> > +++ b/.gitignore
> > @@ -111,3 +111,9 @@ tags
> >  TAGS
> >  docker-src.*
> >  *~
> > +trace.h
> > +trace.c
> > +trace-events-common
> > +trace-ust.h
> > +trace-dtrace.h
> > +trace-dtrace.dtrace
> > diff --git a/Makefile b/Makefile
> > index 214cbad..181802b 100644
> > --- a/Makefile
> > +++ b/Makefile
> > @@ -70,11 +70,53 @@ GENERATED_SOURCES += trace/generated-helpers.c
>  
> >  ifeq ($(findstring ust,$(TRACE_BACKENDS)),ust)
> >  GENERATED_HEADERS += trace/generated-ust-provider.h
> > +GENERATED_HEADERS += trace/generated-ust-provider-all.h
> >  GENERATED_SOURCES += trace/generated-ust.c
> >  endif
>  
> >  GENERATED_HEADERS += module_block.h
>  
> > +GENERATED_HEADERS += $(trace-events-subdirs:%=%/trace.h)
> > +GENERATED_SOURCES += $(trace-events-subdirs:%=%/trace.c)
> > +GENERATED_DTRACE =
> > +ifdef CONFIG_TRACE_DTRACE
> > +GENERATED_HEADERS += $(trace-events-subdirs:%=%/trace-dtrace.h)
> > +GENERATED_DTRACE += $(trace-events-subdirs:%=%/trace-dtrace.dtrace)
> > +endif
> > +ifdef CONFIG_TRACE_UST
> > +GENERATED_HEADERS += $(trace-events-subdirs:%=%/trace-ust.h)
> > +endif
> > +
> > +%/trace.h: $(SRC_PATH)/%/trace-events $(tracetool-y)
> > +	$(call quiet-command,$(TRACETOOL) \
> > +		--format=h \
> > +		--backends=$(TRACE_BACKENDS) \
> > +		$< > $@,"GEN","$@")
> > +
> > +%/trace.c: $(SRC_PATH)/%/trace-events $(tracetool-y)
> > +	$(call quiet-command,$(TRACETOOL) \
> > +		--format=c \
> > +		--backends=$(TRACE_BACKENDS) \
> > +		$< > $@,"GEN","$@")
> > +
> > +%/trace-ust.h: $(SRC_PATH)/%/trace-events $(tracetool-y)
> > +	$(call quiet-command,$(TRACETOOL) \
> > +		--format=ust-events-h \
> > +		--backends=$(TRACE_BACKENDS) \
> > +		$< > $@,"GEN","$@")
> 
> There's a discrepancy between generation in trace/Makefile.objs, where timestamp
> files are used to filter out internal changes in tracetool, and here.

I took the view that the timestamp comparisons are an uneccessary
complexity - we don't do that for other places where we generate
code from scripts.

> > diff --git a/scripts/tracetool/backend/dtrace.py b/scripts/tracetool/backend/dtrace.py
> > index 79505c6..1319990 100644
> > --- a/scripts/tracetool/backend/dtrace.py
> > +++ b/scripts/tracetool/backend/dtrace.py
> > @@ -36,7 +36,12 @@ def binary():
>  
>  
> >  def generate_h_begin(events, group):
> > -    out('#include "trace/generated-tracers-dtrace.h"',
> > +    if group == "common":
> > +        include = "trace/generated-tracers-dtrace.h"
> > +    else:
> > +        include = "trace-dtrace.h"
> > +
> > +    out('#include "%s"' % include,
> >          '')
> 
> Why is the top-level events file treated as a special case?

This is temporary until the end of the series when the special
cases go away


Regards,
Daniel
-- 
|: http://berrange.com      -o-    http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org              -o-             http://virt-manager.org :|
|: http://entangle-photo.org       -o-    http://search.cpan.org/~danberr/ :|