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| author |   Martin KaFai Lau <kafai@fb.com> | 2018-11-19 15:29:08 -0800 |
|---|---|---|
| committer |   Alexei Starovoitov <ast@kernel.org> | 2018-11-20 10:54:38 -0800 |
| commit | 2667a2626f4da370409c2830552f6e8c8b8c41e2 (patch) | |
| tree | c6eba2292a81ead78b2c48075c8f7eb75588a172 /include | |
| parent | bpf: btf: Break up btf_type_is_void() (diff) | |
| download | linux-dev-2667a2626f4da370409c2830552f6e8c8b8c41e2.tar.xz linux-dev-2667a2626f4da370409c2830552f6e8c8b8c41e2.zip | |
bpf: btf: Add BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO
This patch adds BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO
to support the function debug info.
BTF_KIND_FUNC_PROTO must not have a name (i.e. !t->name_off)
and it is followed by >= 0 'struct bpf_param' objects to
describe the function arguments.
The BTF_KIND_FUNC must have a valid name and it must
refer back to a BTF_KIND_FUNC_PROTO.
The above is the conclusion after the discussion between
Edward Cree, Alexei, Daniel, Yonghong and Martin.
By combining BTF_KIND_FUNC and BTF_LIND_FUNC_PROTO,
a complete function signature can be obtained. It will be
used in the later patches to learn the function signature of
a running bpf program.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/uapi/linux/btf.h | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/include/uapi/linux/btf.h b/include/uapi/linux/btf.h index 972265f32871..14f66948fc95 100644 --- a/include/uapi/linux/btf.h +++ b/include/uapi/linux/btf.h @@ -40,7 +40,8 @@ struct btf_type { /* "size" is used by INT, ENUM, STRUCT and UNION. * "size" tells the size of the type it is describing. * - * "type" is used by PTR, TYPEDEF, VOLATILE, CONST and RESTRICT. + * "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT, + * FUNC and FUNC_PROTO. * "type" is a type_id referring to another type. */ union { @@ -64,8 +65,10 @@ struct btf_type { #define BTF_KIND_VOLATILE 9 /* Volatile */ #define BTF_KIND_CONST 10 /* Const */ #define BTF_KIND_RESTRICT 11 /* Restrict */ -#define BTF_KIND_MAX 11 -#define NR_BTF_KINDS 12 +#define BTF_KIND_FUNC 12 /* Function */ +#define BTF_KIND_FUNC_PROTO 13 /* Function Proto */ +#define BTF_KIND_MAX 13 +#define NR_BTF_KINDS 14 /* For some specific BTF_KIND, "struct btf_type" is immediately * followed by extra data. @@ -110,4 +113,13 @@ struct btf_member { __u32 offset; /* offset in bits */ }; +/* BTF_KIND_FUNC_PROTO is followed by multiple "struct btf_param". + * The exact number of btf_param is stored in the vlen (of the + * info in "struct btf_type"). + */ +struct btf_param { + __u32 name_off; + __u32 type; +}; + #endif /* _UAPI__LINUX_BTF_H__ */ |