On Thu, Mar 12, 2020 at 6:04 AM Tobias Klauser <tklauser@xxxxxxxxxx> wrote:
>
> When compiling bpftool on a system where the /usr/include/asm symlink
> doesn't exist (e.g. on an Ubuntu system without gcc-multilib installed),
> the build fails with:
>
> CLANG skeleton/profiler.bpf.o
> In file included from skeleton/profiler.bpf.c:4:
> In file included from /usr/include/linux/bpf.h:11:
> /usr/include/linux/types.h:5:10: fatal error: 'asm/types.h' file not found
> #include <asm/types.h>
> ^~~~~~~~~~~~~
> 1 error generated.
> make: *** [Makefile:123: skeleton/profiler.bpf.o] Error 1
>
> This indicates that the build is using linux/types.h from system headers
> instead of source tree headers.
>
> To fix this, adjust the clang search path to include the necessary
> headers from tools/testing/selftests/bpf/include/uapi and
> tools/include/uapi. Also use __bitwise__ instead of __bitwise in
> skeleton/profiler.h to avoid clashing with the definition in
> tools/testing/selftests/bpf/include/uapi/linux/types.h.
>
> Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
> Cc: Song Liu <songliubraving@xxxxxx>
> Cc: Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx>
> Cc: Quentin Monnet <quentin@xxxxxxxxxxxxx>
> Signed-off-by: Tobias Klauser <tklauser@xxxxxxxxxx>
> ---
> tools/bpf/bpftool/Makefile | 5 ++++-
> tools/bpf/bpftool/skeleton/profiler.h | 17 ++++++++---------
> 2 files changed, 12 insertions(+), 10 deletions(-)
>
> diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile
> index 20a90d8450f8..f294f6c1e795 100644
> --- a/tools/bpf/bpftool/Makefile
> +++ b/tools/bpf/bpftool/Makefile
> @@ -120,7 +120,10 @@ $(OUTPUT)_bpftool: $(_OBJS) $(LIBBPF)
> $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $(_OBJS) $(LIBS)
>
> skeleton/profiler.bpf.o: skeleton/profiler.bpf.c
> - $(QUIET_CLANG)$(CLANG) -I$(srctree)/tools/lib -g -O2 -target bpf -c $< -o $@
> + $(QUIET_CLANG)$(CLANG) \
> + -I$(srctree)/tools/include/uapi/ \
> + -I$(srctree)/tools/testing/selftests/bpf/include/uapi \
Seems like I'm spoiling all the fun today :) But why are we ok with
bpftool build depending on selftests? This just makes it even harder
to have a stand-alone bpftool build eventually (similar to libbpf's
Github).
> + -I$(srctree)/tools/lib -g -O2 -target bpf -c $< -o $@
>
> profiler.skel.h: $(OUTPUT)_bpftool skeleton/profiler.bpf.o
> $(QUIET_GEN)$(OUTPUT)./_bpftool gen skeleton skeleton/profiler.bpf.o > $@
> diff --git a/tools/bpf/bpftool/skeleton/profiler.h b/tools/bpf/bpftool/skeleton/profiler.h
> index e03b53eae767..1f767e9510f7 100644
> --- a/tools/bpf/bpftool/skeleton/profiler.h
> +++ b/tools/bpf/bpftool/skeleton/profiler.h
> @@ -32,16 +32,15 @@ enum {
> #else
> #define __bitwise__
> #endif
> -#define __bitwise __bitwise__
>
> -typedef __u16 __bitwise __le16;
> -typedef __u16 __bitwise __be16;
> -typedef __u32 __bitwise __le32;
> -typedef __u32 __bitwise __be32;
> -typedef __u64 __bitwise __le64;
> -typedef __u64 __bitwise __be64;
> +typedef __u16 __bitwise__ __le16;
> +typedef __u16 __bitwise__ __be16;
> +typedef __u32 __bitwise__ __le32;
> +typedef __u32 __bitwise__ __be32;
> +typedef __u64 __bitwise__ __le64;
> +typedef __u64 __bitwise__ __be64;
>
> -typedef __u16 __bitwise __sum16;
> -typedef __u32 __bitwise __wsum;
> +typedef __u16 __bitwise__ __sum16;
> +typedef __u32 __bitwise__ __wsum;
>
> #endif /* __PROFILER_H */
> --
> 2.25.1
>
