On Wed, Oct 2, 2019 at 3:01 PM Andrii Nakryiko <andriin@xxxxxx> wrote:
>
> To allow adding a variadic BPF_CORE_READ macro with slightly different
> syntax and semantics, define CORE_READ in CO-RE reloc tests, which is
> a thin wrapper around low-level bpf_core_read() macro, which in turn is
> just a wrapper around bpf_probe_read().
>
> Acked-by: John Fastabend <john.fastabend@xxxxxxxxx>
> Acked-by: Song Liu <songliubraving@xxxxxx>
> Signed-off-by: Andrii Nakryiko <andriin@xxxxxx>
> ---
> tools/testing/selftests/bpf/bpf_helpers.h | 8 ++++----
> .../bpf/progs/test_core_reloc_arrays.c | 10 ++++++----
> .../bpf/progs/test_core_reloc_flavors.c | 8 +++++---
> .../selftests/bpf/progs/test_core_reloc_ints.c | 18 ++++++++++--------
> .../bpf/progs/test_core_reloc_kernel.c | 6 ++++--
> .../selftests/bpf/progs/test_core_reloc_misc.c | 8 +++++---
> .../selftests/bpf/progs/test_core_reloc_mods.c | 18 ++++++++++--------
> .../bpf/progs/test_core_reloc_nesting.c | 6 ++++--
> .../bpf/progs/test_core_reloc_primitives.c | 12 +++++++-----
> .../bpf/progs/test_core_reloc_ptr_as_arr.c | 4 +++-
> 10 files changed, 58 insertions(+), 40 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
> index 7b75c38238e4..5210cc7d7c5c 100644
> --- a/tools/testing/selftests/bpf/bpf_helpers.h
> +++ b/tools/testing/selftests/bpf/bpf_helpers.h
> @@ -483,7 +483,7 @@ struct pt_regs;
> #endif
>
> /*
> - * BPF_CORE_READ abstracts away bpf_probe_read() call and captures offset
> + * bpf_core_read() abstracts away bpf_probe_read() call and captures offset
> * relocation for source address using __builtin_preserve_access_index()
> * built-in, provided by Clang.
> *
> @@ -498,8 +498,8 @@ struct pt_regs;
> * actual field offset, based on target kernel BTF type that matches original
> * (local) BTF, used to record relocation.
> */
> -#define BPF_CORE_READ(dst, src) \
> - bpf_probe_read((dst), sizeof(*(src)), \
> - __builtin_preserve_access_index(src))
> +#define bpf_core_read(dst, sz, src) \
> + bpf_probe_read(dst, sz, \
> + (const void *)__builtin_preserve_access_index(src))
>
> #endif
> diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c b/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c
> index bf67f0fdf743..58efe4944594 100644
> --- a/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c
> +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c
> @@ -31,6 +31,8 @@ struct core_reloc_arrays {
> struct core_reloc_arrays_substruct d[1][2];
> };
>
> +#define CORE_READ(dst, src) bpf_core_read(dst, sizeof(*dst), src)
We are using sizeof(*dst) now, but I guess sizeof(*src) is better?
And it should be sizeof(*(src)).
> +
> SEC("raw_tracepoint/sys_enter")
> int test_core_arrays(void *ctx)
> {
> @@ -38,16 +40,16 @@ int test_core_arrays(void *ctx)
> struct core_reloc_arrays_output *out = (void *)&data.out;
>
> /* in->a[2] */
> - if (BPF_CORE_READ(&out->a2, &in->a[2]))
> + if (CORE_READ(&out->a2, &in->a[2]))
> return 1;
> /* in->b[1][2][3] */
> - if (BPF_CORE_READ(&out->b123, &in->b[1][2][3]))
> + if (CORE_READ(&out->b123, &in->b[1][2][3]))
> return 1;
> /* in->c[1].c */
> - if (BPF_CORE_READ(&out->c1c, &in->c[1].c))
> + if (CORE_READ(&out->c1c, &in->c[1].c))
> return 1;
> /* in->d[0][0].d */
> - if (BPF_CORE_READ(&out->d00d, &in->d[0][0].d))
> + if (CORE_READ(&out->d00d, &in->d[0][0].d))
> return 1;
>
> return 0;
> diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_flavors.c b/tools/testing/selftests/bpf/progs/test_core_reloc_flavors.c
> index 9fda73e87972..3348acc7e50b 100644
> --- a/tools/testing/selftests/bpf/progs/test_core_reloc_flavors.c
> +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_flavors.c
> @@ -39,6 +39,8 @@ struct core_reloc_flavors___weird {
> };
> };
>
> +#define CORE_READ(dst, src) bpf_core_read(dst, sizeof(*dst), src)
> +
> SEC("raw_tracepoint/sys_enter")
> int test_core_flavors(void *ctx)
> {
> @@ -48,13 +50,13 @@ int test_core_flavors(void *ctx)
> struct core_reloc_flavors *out = (void *)&data.out;
>
> /* read a using weird layout */
> - if (BPF_CORE_READ(&out->a, &in_weird->a))
> + if (CORE_READ(&out->a, &in_weird->a))
> return 1;
> /* read b using reversed layout */
> - if (BPF_CORE_READ(&out->b, &in_rev->b))
> + if (CORE_READ(&out->b, &in_rev->b))
> return 1;
> /* read c using original layout */
> - if (BPF_CORE_READ(&out->c, &in_orig->c))
> + if (CORE_READ(&out->c, &in_orig->c))
> return 1;
>
> return 0;
> diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_ints.c b/tools/testing/selftests/bpf/progs/test_core_reloc_ints.c
> index d99233c8008a..cfe16ede48dd 100644
> --- a/tools/testing/selftests/bpf/progs/test_core_reloc_ints.c
> +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_ints.c
> @@ -23,20 +23,22 @@ struct core_reloc_ints {
> int64_t s64_field;
> };
>
> +#define CORE_READ(dst, src) bpf_core_read(dst, sizeof(*dst), src)
ditto.
> +
> SEC("raw_tracepoint/sys_enter")
> int test_core_ints(void *ctx)
> {
> struct core_reloc_ints *in = (void *)&data.in;
> struct core_reloc_ints *out = (void *)&data.out;
>
> - if (BPF_CORE_READ(&out->u8_field, &in->u8_field) ||
> - BPF_CORE_READ(&out->s8_field, &in->s8_field) ||
> - BPF_CORE_READ(&out->u16_field, &in->u16_field) ||
> - BPF_CORE_READ(&out->s16_field, &in->s16_field) ||
> - BPF_CORE_READ(&out->u32_field, &in->u32_field) ||
> - BPF_CORE_READ(&out->s32_field, &in->s32_field) ||
> - BPF_CORE_READ(&out->u64_field, &in->u64_field) ||
> - BPF_CORE_READ(&out->s64_field, &in->s64_field))
> + if (CORE_READ(&out->u8_field, &in->u8_field) ||
> + CORE_READ(&out->s8_field, &in->s8_field) ||
> + CORE_READ(&out->u16_field, &in->u16_field) ||
> + CORE_READ(&out->s16_field, &in->s16_field) ||
> + CORE_READ(&out->u32_field, &in->u32_field) ||
> + CORE_READ(&out->s32_field, &in->s32_field) ||
> + CORE_READ(&out->u64_field, &in->u64_field) ||
> + CORE_READ(&out->s64_field, &in->s64_field))
> return 1;
>
> return 0;
> diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c b/tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c
> index 37e02aa3f0c8..e5308026cfda 100644
> --- a/tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c
> +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c
> @@ -17,6 +17,8 @@ struct task_struct {
> int tgid;
> };
>
> +#define CORE_READ(dst, src) bpf_core_read(dst, sizeof(*dst), src)
ditto again, and more below.
Thanks,
Song
