[v2,1/2] perf build: Update build rule for generated files

  The bison and flex generate C files from the source (.y and .l)
files.  When O= option is used, they are saved in a separate directory
but the default build rule assumes the .C files are in the source
directory.  So it might read invalid file if there are generated files
from an old version.  The same is true for the pmu-events files.

For example, the following command would cause a build failure:

  $ git checkout v6.3
  $ make -C tools/perf  # build in the same directory

  $ git checkout v6.5-rc2
  $ mkdir build  # create a build directory
  $ make -C tools/perf O=build  # build in a different directory but it
                                # refers files in the source directory

Let's update the build rule to specify those cases explicitly to depend
on the files in the output directory.

Note that it's not a complete fix and it needs the next patch for the
include path too.

Fixes: 80eeb67fe577 ("perf jevents: Program to convert JSON file")
Cc: stable@vger.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/build/Makefile.build  | 10 ++++++++++
 tools/perf/pmu-events/Build |  6 ++++++
 2 files changed, 16 insertions(+)
  

Em Thu, Jul 27, 2023 at 07:24:46PM -0700, Namhyung Kim escreveu:
> The bison and flex generate C files from the source (.y and .l)
> files.  When O= option is used, they are saved in a separate directory
> but the default build rule assumes the .C files are in the source
> directory.  So it might read invalid file if there are generated files
> from an old version.  The same is true for the pmu-events files.
> 
> For example, the following command would cause a build failure:
> 
>   $ git checkout v6.3
>   $ make -C tools/perf  # build in the same directory
> 
>   $ git checkout v6.5-rc2
>   $ mkdir build  # create a build directory
>   $ make -C tools/perf O=build  # build in a different directory but it
>                                 # refers files in the source directory
> 
> Let's update the build rule to specify those cases explicitly to depend
> on the files in the output directory.
> 
> Note that it's not a complete fix and it needs the next patch for the
> include path too.

Applied, testing it on the container builds.

- Arnaldo
 
> Fixes: 80eeb67fe577 ("perf jevents: Program to convert JSON file")
> Cc: stable@vger.kernel.org
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> ---
>  tools/build/Makefile.build  | 10 ++++++++++
>  tools/perf/pmu-events/Build |  6 ++++++
>  2 files changed, 16 insertions(+)
> 
> diff --git a/tools/build/Makefile.build b/tools/build/Makefile.build
> index 89430338a3d9..fac42486a8cf 100644
> --- a/tools/build/Makefile.build
> +++ b/tools/build/Makefile.build
> @@ -117,6 +117,16 @@ $(OUTPUT)%.s: %.c FORCE
>  	$(call rule_mkdir)
>  	$(call if_changed_dep,cc_s_c)
>  
> +# bison and flex files are generated in the OUTPUT directory
> +# so it needs a separate rule to depend on them properly
> +$(OUTPUT)%-bison.o: $(OUTPUT)%-bison.c FORCE
> +	$(call rule_mkdir)
> +	$(call if_changed_dep,$(host)cc_o_c)
> +
> +$(OUTPUT)%-flex.o: $(OUTPUT)%-flex.c FORCE
> +	$(call rule_mkdir)
> +	$(call if_changed_dep,$(host)cc_o_c)
> +
>  # Gather build data:
>  #   obj-y        - list of build objects
>  #   subdir-y     - list of directories to nest
> diff --git a/tools/perf/pmu-events/Build b/tools/perf/pmu-events/Build
> index 150765f2baee..1d18bb89402e 100644
> --- a/tools/perf/pmu-events/Build
> +++ b/tools/perf/pmu-events/Build
> @@ -35,3 +35,9 @@ $(PMU_EVENTS_C): $(JSON) $(JSON_TEST) $(JEVENTS_PY) $(METRIC_PY) $(METRIC_TEST_L
>  	$(call rule_mkdir)
>  	$(Q)$(call echo-cmd,gen)$(PYTHON) $(JEVENTS_PY) $(JEVENTS_ARCH) $(JEVENTS_MODEL) pmu-events/arch $@
>  endif
> +
> +# pmu-events.c file is generated in the OUTPUT directory so it needs a
> +# separate rule to depend on it properly
> +$(OUTPUT)pmu-events/pmu-events.o: $(PMU_EVENTS_C)
> +	$(call rule_mkdir)
> +	$(call if_changed_dep,cc_o_c)
> -- 
> 2.41.0.487.g6d72f3e995-goog
>
  

Hi Arnaldo,

On Fri, Jul 28, 2023 at 11:09 PM Arnaldo Carvalho de Melo
<acme@kernel.org> wrote:
>
> Em Thu, Jul 27, 2023 at 07:24:46PM -0700, Namhyung Kim escreveu:
> > The bison and flex generate C files from the source (.y and .l)
> > files.  When O= option is used, they are saved in a separate directory
> > but the default build rule assumes the .C files are in the source
> > directory.  So it might read invalid file if there are generated files
> > from an old version.  The same is true for the pmu-events files.
> >
> > For example, the following command would cause a build failure:
> >
> >   $ git checkout v6.3
> >   $ make -C tools/perf  # build in the same directory
> >
> >   $ git checkout v6.5-rc2
> >   $ mkdir build  # create a build directory
> >   $ make -C tools/perf O=build  # build in a different directory but it
> >                                 # refers files in the source directory
> >
> > Let's update the build rule to specify those cases explicitly to depend
> > on the files in the output directory.
> >
> > Note that it's not a complete fix and it needs the next patch for the
> > include path too.
>
> Applied, testing it on the container builds.

I don't see these commits in the perf-tools{,-next} yet.

Thanks,
Namhyung
  

Em Wed, Aug 09, 2023 at 03:56:17PM +0900, Namhyung Kim escreveu:
> On Fri, Jul 28, 2023 at 11:09 PM Arnaldo Carvalho de Melo <acme@kernel.org> wrote:
> > Em Thu, Jul 27, 2023 at 07:24:46PM -0700, Namhyung Kim escreveu:
> > > Let's update the build rule to specify those cases explicitly to depend
> > > on the files in the output directory.

> > > Note that it's not a complete fix and it needs the next patch for the
> > > include path too.

> > Applied, testing it on the container builds.

> I don't see these commits in the perf-tools{,-next} yet.

6 days	perf build: Include generated header files properly	Namhyung Kim	5	-9/+9
6 days	perf build: Update build rule for generated files	Namhyung Kim	2	-0/+16

https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/commit/?h=perf-tools-next&id=7822a8913f4c51c7d1aff793b525d60c3384fb5b
https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/commit/?h=perf-tools-next&id=c7e97f215a4ad634b746804679f5937d25f77e29

Did I miss something?

- Arnaldo
  

On Wed, Aug 9, 2023 at 10:28 PM Arnaldo Carvalho de Melo
<acme@kernel.org> wrote:
>
> Em Wed, Aug 09, 2023 at 03:56:17PM +0900, Namhyung Kim escreveu:
> > On Fri, Jul 28, 2023 at 11:09 PM Arnaldo Carvalho de Melo <acme@kernel.org> wrote:
> > > Em Thu, Jul 27, 2023 at 07:24:46PM -0700, Namhyung Kim escreveu:
> > > > Let's update the build rule to specify those cases explicitly to depend
> > > > on the files in the output directory.
>
> > > > Note that it's not a complete fix and it needs the next patch for the
> > > > include path too.
>
> > > Applied, testing it on the container builds.
>
> > I don't see these commits in the perf-tools{,-next} yet.
>
> 6 days  perf build: Include generated header files properly     Namhyung Kim    5       -9/+9
> 6 days  perf build: Update build rule for generated files       Namhyung Kim    2       -0/+16
>
> https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/commit/?h=perf-tools-next&id=7822a8913f4c51c7d1aff793b525d60c3384fb5b
> https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/commit/?h=perf-tools-next&id=c7e97f215a4ad634b746804679f5937d25f77e29
>
> Did I miss something?

Oops, my bad.  I somehow overlooked the commits.
Now I can see it in the perf-tools-next, sorry for the noise.

Thanks,
Namhyung