Re: [PATCH 2/3] libbpf: support detecting and attaching of writable tracepoint program

[Yonghong Song <yhs@fb.com>]

On 9/16/21 6:55 AM, Hou Tao wrote:
> Program on writable tracepoint is BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
> but its attachment is the same as BPF_PROG_TYPE_RAW_TRACEPOINT.
> 
> Signed-off-by: Hou Tao <houtao1@huawei.com>
> ---
>   tools/lib/bpf/libbpf.c | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index 88d8825fc6f6..e6a1d552040c 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -7942,6 +7942,10 @@ static const struct bpf_sec_def section_defs[] = {
>   		.attach_fn = attach_raw_tp),
>   	SEC_DEF("raw_tp/", RAW_TRACEPOINT,
>   		.attach_fn = attach_raw_tp),
> +	SEC_DEF("raw_tracepoint_writable/", RAW_TRACEPOINT_WRITABLE,
> +		.attach_fn = attach_raw_tp),
> +	SEC_DEF("raw_tp_writable/", RAW_TRACEPOINT_WRITABLE,
> +		.attach_fn = attach_raw_tp),

Looks like initially ([1]) we don't have C bpf program test case for 
RAW_TRACEPOINT_WRITABLE, so the above sec definition is missing.

  [1] e950e843367d7 selftests: bpf: test writable buffers in raw tps

>   	SEC_DEF("tp_btf/", TRACING,
>   		.expected_attach_type = BPF_TRACE_RAW_TP,
>   		.is_attach_btf = true,
>