On Mon, Nov 18, 2019 at 5:38 PM Daniel Borkmann <daniel@xxxxxxxxxxxxx> wrote:
>
> Add initial poke table data structures and management to the BPF
> prog that can later be used by JITs. Also add an instance of poke
> specific data for tail call maps; plan for later work is to extend
> this also for BPF static keys.
>
> Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
> Acked-by: Andrii Nakryiko <andriin@xxxxxx>
> ---
> include/linux/bpf.h | 20 ++++++++++++++++++++
> include/linux/filter.h | 10 ++++++++++
> kernel/bpf/core.c | 34 ++++++++++++++++++++++++++++++++++
> 3 files changed, 64 insertions(+)
>
> diff --git a/include/linux/bpf.h b/include/linux/bpf.h
> index 836e49855bf9..cad4382c1265 100644
> --- a/include/linux/bpf.h
> +++ b/include/linux/bpf.h
> @@ -488,6 +488,24 @@ struct bpf_func_info_aux {
> bool unreliable;
> };
>
> +enum bpf_jit_poke_reason {
> + BPF_POKE_REASON_TAIL_CALL,
> +};
> +
> +/* Descriptor of pokes pointing /into/ the JITed image. */
> +struct bpf_jit_poke_descriptor {
> + void *ip;
> + union {
> + struct {
> + struct bpf_map *map;
> + u32 key;
> + } tail_call;
> + };
> + u8 ip_stable;
this one is bool, any reason you used u8 instead?
> + u8 adj_off;
> + u16 reason;
> +};
> +
[...]
