Re: [RFC PATCH bpf-next v5 7/8] selftests/bpf: move shared build definitions into Makefile.buildvars

On Wed, Aug 5, 2026 at 4:34 PM Eduard Zingerman <[email protected]> wrote:
>
> On Tue, 2026-08-04 at 10:01 -0700, Mykola Lysenko wrote:
>
> ...
>
> Thank you for taking time to reshuffle the diff, such that the
> Makefile.buildvars preserves the original relative order.
> Much easier to review.

Thank you for taking time to review!

>
> ...
>
> > --- a/tools/testing/selftests/bpf/Makefile
> > +++ b/tools/testing/selftests/bpf/Makefile
> > @@ -3,60 +3,15 @@ include ../../../build/Build.include
>
> ...
>
> > -GENHDR := $(GENDIR)/autoconf.h
> >  PKG_CONFIG ?= $(CROSS_COMPILE)pkg-config
>    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> It seems this can be removed as well, all uses are after
> Makefile.buildvars is included. Or is it needed for one of the other
> includes?

It is not - none of the earlier includes reference PKG_CONFIG (or
srctree), and the remaining uses in the top Makefile are all
recipe-time, after the include.

>
> ...
>
> > @@ -220,21 +151,8 @@ ifeq ($(feature-llvm),1)
>
> ...
>
> > -HOST_BPFOBJ := $(HOST_BUILD_DIR)/libbpf/libbpf.a
> > -RESOLVE_BTFIDS := $(HOST_BUILD_DIR)/resolve_btfids/resolve_btfids
> > +include Makefile.buildvars
>
> It appears that this include can be moved up, to the lib.mk include.
> In this case the duplicate definitions for `srctree` and `PKG_CONFIG`
> can be removed (and both can reside in Makefile.buildvars).
> Wdyt?

Agreed, will do in v6.

>
> ...
>
> > --- /dev/null
> > +++ b/tools/testing/selftests/bpf/Makefile.buildvars
>
> ...
>
> > +PKG_CONFIG ?= $(CROSS_COMPILE)pkg-config
>
> ...
>
> > +ifeq ($(srctree),)
> > +srctree := $(patsubst %/,%,$(dir $(CURDIR)))
> > +srctree := $(patsubst %/,%,$(dir $(srctree)))
> > +srctree := $(patsubst %/,%,$(dir $(srctree)))
> > +srctree := $(patsubst %/,%,$(dir $(srctree)))
> > +endif
>
> In case if shuffling includes around does not work, can we export
> `srctree` in the main makefile and not copy it here?

Not needed with the above. Thanks!

>
> ...