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

* [PATCH] tools include: Add __sum16 and __wsum definitions.
@ 2021-03-07 22:30 Ian Rogers
  2021-03-08 13:37 ` Daniel Borkmann
  0 siblings, 1 reply; 3+ messages in thread
From: Ian Rogers @ 2021-03-07 22:30 UTC (permalink / raw)
  To: Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo,
	Mark Rutland, Alexander Shishkin, Jiri Olsa, Namhyung Kim,
	Song Liu, linux-kernel, Alexei Starovoitov, Daniel Borkmann,
	Andrii Nakryiko, Martin KaFai Lau, Yonghong Song, John Fastabend,
	KP Singh, Tiezhu Yang, netdev, bpf
  Cc: Stephane Eranian, Ian Rogers

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 <irogers@google.com>
---
 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


^ permalink raw reply related	[flat|nested] 3+ messages in thread