2021-03-08 08:30:34

by Ian Rogers

[permalink] [raw]
Subject: [PATCH] tools include: Add __sum16 and __wsum definitions.

This adds definitions available in the uapi version.

Explanation:
In the kernel include of types.h the uapi version is included.
In tools the uapi/linux/types.h and linux/types.h are distinct.
For BPF programs a definition of __wsum is needed by the generated
bpf_helpers.h. The definition comes either from a generated vmlinux.h or
from <linux/types.h> that may be transitively included from bpf.h. The
perf build prefers linux/types.h over uapi/linux/types.h for
<linux/types.h>*. To allow tools/perf/util/bpf_skel/bpf_prog_profiler.bpf.c
to compile with the same include path used for perf then these
definitions are necessary.

There is likely a wider conversation about exactly how types.h should be
specified and the include order used by the perf build - it is somewhat
confusing that tools/include/uapi/linux/bpf.h is using the non-uapi
types.h.

*see tools/perf/Makefile.config:
...
INC_FLAGS += -I$(srctree)/tools/include/
INC_FLAGS += -I$(srctree)/tools/arch/$(SRCARCH)/include/uapi
INC_FLAGS += -I$(srctree)/tools/include/uapi
...
The include directories are scanned from left-to-right:
https://gcc.gnu.org/onlinedocs/gcc/Directory-Options.html
As tools/include/linux/types.h appears before
tools/include/uapi/linux/types.h then I say it is preferred.

Signed-off-by: Ian Rogers <[email protected]>
---
tools/include/linux/types.h | 3 +++
1 file changed, 3 insertions(+)

diff --git a/tools/include/linux/types.h b/tools/include/linux/types.h
index e9c5a215837d..6e14a533ab4e 100644
--- a/tools/include/linux/types.h
+++ b/tools/include/linux/types.h
@@ -61,6 +61,9 @@ typedef __u32 __bitwise __be32;
typedef __u64 __bitwise __le64;
typedef __u64 __bitwise __be64;

+typedef __u16 __bitwise __sum16;
+typedef __u32 __bitwise __wsum;
+
typedef struct {
int counter;
} atomic_t;
--
2.30.1.766.gb4fecdf3b7-goog


2021-03-08 13:40:16

by Daniel Borkmann

[permalink] [raw]
Subject: Re: [PATCH] tools include: Add __sum16 and __wsum definitions.

On 3/7/21 11:30 PM, Ian Rogers wrote:
> This adds definitions available in the uapi version.
>
> Explanation:
> In the kernel include of types.h the uapi version is included.
> In tools the uapi/linux/types.h and linux/types.h are distinct.
> For BPF programs a definition of __wsum is needed by the generated
> bpf_helpers.h. The definition comes either from a generated vmlinux.h or
> from <linux/types.h> that may be transitively included from bpf.h. The
> perf build prefers linux/types.h over uapi/linux/types.h for
> <linux/types.h>*. To allow tools/perf/util/bpf_skel/bpf_prog_profiler.bpf.c
> to compile with the same include path used for perf then these
> definitions are necessary.
>
> There is likely a wider conversation about exactly how types.h should be
> specified and the include order used by the perf build - it is somewhat
> confusing that tools/include/uapi/linux/bpf.h is using the non-uapi
> types.h.
>
> *see tools/perf/Makefile.config:
> ...
> INC_FLAGS += -I$(srctree)/tools/include/
> INC_FLAGS += -I$(srctree)/tools/arch/$(SRCARCH)/include/uapi
> INC_FLAGS += -I$(srctree)/tools/include/uapi
> ...
> The include directories are scanned from left-to-right:
> https://gcc.gnu.org/onlinedocs/gcc/Directory-Options.html
> As tools/include/linux/types.h appears before
> tools/include/uapi/linux/types.h then I say it is preferred.
>
> Signed-off-by: Ian Rogers <[email protected]>

Given more related to perf build infra, I presume Arnaldo would pick
this one up?

Thanks,
Daniel

2021-03-08 13:43:33

by Arnaldo Carvalho de Melo

[permalink] [raw]
Subject: Re: [PATCH] tools include: Add __sum16 and __wsum definitions.

Em Mon, Mar 08, 2021 at 02:37:32PM +0100, Daniel Borkmann escreveu:
> On 3/7/21 11:30 PM, Ian Rogers wrote:
> > This adds definitions available in the uapi version.
> >
> > Explanation:
> > In the kernel include of types.h the uapi version is included.
> > In tools the uapi/linux/types.h and linux/types.h are distinct.
> > For BPF programs a definition of __wsum is needed by the generated
> > bpf_helpers.h. The definition comes either from a generated vmlinux.h or
> > from <linux/types.h> that may be transitively included from bpf.h. The
> > perf build prefers linux/types.h over uapi/linux/types.h for
> > <linux/types.h>*. To allow tools/perf/util/bpf_skel/bpf_prog_profiler.bpf.c
> > to compile with the same include path used for perf then these
> > definitions are necessary.
> >
> > There is likely a wider conversation about exactly how types.h should be
> > specified and the include order used by the perf build - it is somewhat
> > confusing that tools/include/uapi/linux/bpf.h is using the non-uapi
> > types.h.
> >
> > *see tools/perf/Makefile.config:
> > ...
> > INC_FLAGS += -I$(srctree)/tools/include/
> > INC_FLAGS += -I$(srctree)/tools/arch/$(SRCARCH)/include/uapi
> > INC_FLAGS += -I$(srctree)/tools/include/uapi
> > ...
> > The include directories are scanned from left-to-right:
> > https://gcc.gnu.org/onlinedocs/gcc/Directory-Options.html
> > As tools/include/linux/types.h appears before
> > tools/include/uapi/linux/types.h then I say it is preferred.
> >
> > Signed-off-by: Ian Rogers <[email protected]>
>
> Given more related to perf build infra, I presume Arnaldo would pick
> this one up?

I'll process it.

- Arnaldo