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

On Tue, 2026-08-04 at 10:01 -0700, Mykola Lysenko wrote:

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Thank you for taking time to reshuffle the diff, such that the
Makefile.buildvars preserves the original relative order.
Much easier to review.

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> --- a/tools/testing/selftests/bpf/Makefile
> +++ b/tools/testing/selftests/bpf/Makefile
> @@ -3,60 +3,15 @@ include ../../../build/Build.include

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> -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?

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> @@ -220,21 +151,8 @@ ifeq ($(feature-llvm),1)

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> -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?

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> --- /dev/null
> +++ b/tools/testing/selftests/bpf/Makefile.buildvars

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> +PKG_CONFIG ?= $(CROSS_COMPILE)pkg-config

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> +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?

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