On Fri, Aug 16, 2024 at 7:56 PM Matthieu Baerts (NGI0)
<matttbe@xxxxxxxxxx> wrote:
>
> Instead of duplicating UAPI header files in 'tools/include/uapi', the
> BPF selftests can also look at the header files inside the kernel
> source.
>
> To do that, the kernel selftests infrastructure provides the
> 'KHDR_INCLUDES' variable. This is what is being used in most selftests,
> because it is what is recommended in the documentation [1]. If the
> selftests are not executed from the kernel sources, it is possible to
> override the variable, e.g.
>
> make KHDR_INCLUDES="-I${HDR_DIR}/include" -C "${KSFT_DIR}"
>
> ... where ${HDR_DIR} has been generated by this command:
>
> make headers_install INSTALL_HDR_PATH="${HDR_DIR}"
>
> Thanks to 'KHDR_INCLUDES', it is no longer needed to duplicate header
> files for userspace test programs, and these programs can include UAPI
> header files without the 'uapi' prefix.
>
> Note that it is still required to use 'tools/include/uapi' -- APIDIR,
> which corresponds to TOOLS_INCLUDES from lib.mk -- for the BPF programs,
> not to conflict with what is already defined in vmlinux.h.
>
> Link: https://docs.kernel.org/dev-tools/kselftest.html#contributing-new-tests-details [1]
> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
> ---
> tools/testing/selftests/bpf/Makefile | 2 +-
> tools/testing/selftests/bpf/prog_tests/assign_reuse.c | 2 +-
> tools/testing/selftests/bpf/prog_tests/tc_links.c | 4 ++--
> tools/testing/selftests/bpf/prog_tests/tc_netkit.c | 2 +-
> tools/testing/selftests/bpf/prog_tests/tc_opts.c | 2 +-
> tools/testing/selftests/bpf/prog_tests/user_ringbuf.c | 2 +-
> tools/testing/selftests/bpf/prog_tests/xdp_bonding.c | 2 +-
> tools/testing/selftests/bpf/prog_tests/xdp_cpumap_attach.c | 2 +-
> tools/testing/selftests/bpf/prog_tests/xdp_devmap_attach.c | 2 +-
> tools/testing/selftests/bpf/prog_tests/xdp_do_redirect.c | 2 +-
> tools/testing/selftests/bpf/prog_tests/xdp_link.c | 2 +-
> tools/testing/selftests/bpf/xdp_features.c | 4 ++--
> 12 files changed, 14 insertions(+), 14 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
> index 4eceb491a8ae..6a7aeae7e206 100644
> --- a/tools/testing/selftests/bpf/Makefile
> +++ b/tools/testing/selftests/bpf/Makefile
> @@ -37,7 +37,7 @@ CFLAGS += -g $(OPT_FLAGS) -rdynamic \
> -Wall -Werror -fno-omit-frame-pointer \
> $(GENFLAGS) $(SAN_CFLAGS) $(LIBELF_CFLAGS) \
> -I$(CURDIR) -I$(INCLUDE_DIR) -I$(GENDIR) -I$(LIBDIR) \
> - -I$(TOOLSINCDIR) -I$(APIDIR) -I$(OUTPUT)
> + -I$(TOOLSINCDIR) $(KHDR_INCLUDES) -I$(OUTPUT)
> LDFLAGS += $(SAN_LDFLAGS)
> LDLIBS += $(LIBELF_LIBS) -lz -lrt -lpthread
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/assign_reuse.c b/tools/testing/selftests/bpf/prog_tests/assign_reuse.c
> index 989ee4d9785b..3d06bf5a1ba4 100644
> --- a/tools/testing/selftests/bpf/prog_tests/assign_reuse.c
> +++ b/tools/testing/selftests/bpf/prog_tests/assign_reuse.c
> @@ -1,6 +1,6 @@
> // SPDX-License-Identifier: GPL-2.0
> /* Copyright (c) 2023 Isovalent */
> -#include <uapi/linux/if_link.h>
> +#include <linux/if_link.h>
No. This is not an option.
User space shouldn't include kernel headers like this.
Long ago tools/include directory was specifically
created to break such dependency.
Back then it was done for perf.
pw-bot: cr
