Re: [RFC PATCH net-next] tools/bpftool: use version from the kernel source tree

[Yonghong Song]

On 12/20/17 12:19 PM, Roman Gushchin wrote:
> Bpftool determines it's own version based on the kernel
> version, which is picked from the linux/version.h header.
>
> It's strange to use the version of the installed kernel
> headers, and makes much more sense to use the version
> of the actual source tree, where bpftool sources are.
>
> This patch adds $(srctree)/usr/include to the list
> of include files, which causes bpftool to use the version
> from the source tree.
>
> Example:
> before:
>
> $ bpftool version
> bpftool v4.14.6
>
> after:
> $ bpftool version
> bpftool v4.15.0
>
> Signed-off-by: Roman Gushchin <guro@xxxxxx>
> Cc: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx>
> Cc: Alexei Starovoitov <ast@xxxxxxxxxx>
> Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
> ---
>   tools/bpf/bpftool/Makefile | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile
> index 9c089cfa5f3f..6864d416c49e 100644
> --- a/tools/bpf/bpftool/Makefile
> +++ b/tools/bpf/bpftool/Makefile
> @@ -37,7 +37,9 @@ CC = gcc
>   
>   CFLAGS += -O2
>   CFLAGS += -W -Wall -Wextra -Wno-unused-parameter -Wshadow
> -CFLAGS += -D__EXPORTED_HEADERS__ -I$(srctree)/tools/include/uapi -I$(srctree)/tools/include -I$(srctree)/tools/lib/bpf -I$(srctree)/kernel/bpf/
> +CFLAGS += -D__EXPORTED_HEADERS__ -I$(srctree)/tools/include/uapi
> +CFLAGS += -I$(srctree)/tools/include -I$(srctree)/tools/lib/bpf
> +CFLAGS += -I$(srctree)/kernel/bpf/ -I$(srctree)/usr/include

-I$(srctree)/usr/include may not work if build directory is not the same 
as the source directory. You probably should use
-I$(objtree)/usr/include?

>   LIBS = -lelf -lbfd -lopcodes $(LIBBPF)
>   
>   INSTALL ?= install