Re: [PATCH bpf-next 1/4] bpf: Introduce global percpu data

[Leon Hwang <leon.hwang@linux.dev>]

On 8/2/25 08:23, Alexei Starovoitov wrote:
> On Mon, Jan 27, 2025 at 8:22 AM Leon Hwang <leon.hwang@linux.dev> wrote:
>>
>> +
>> +static int percpu_array_map_direct_value_meta(const struct bpf_map *map,
>> +                                             u64 imm, u32 *off)
>> +{
>> +       struct bpf_array *array = container_of(map, struct bpf_array, map);
>> +       u64 base = (u64) array->pptrs[0];
>> +       u64 range = array->elem_size;
>> +
>> +       if (map->max_entries != 1)
>> +               return -EOPNOTSUPP;
>> +       if (imm < base || imm >= base + range)
>> +               return -ENOENT;
>> +       if (!bpf_jit_supports_percpu_insn())
>> +               return -EOPNOTSUPP;
>> +
>> +       *off = imm - base;
>> +       return 0;
>> +}
> 
> Pls add a selftest for off != 0.
> I think the above should work, but this is not obvious.
> 

Ack.

>>
>> +#ifdef CONFIG_SMP
>> +               if (insn->code == (BPF_LD | BPF_IMM | BPF_DW) &&
>> +                   (insn->src_reg == BPF_PSEUDO_MAP_VALUE ||
>> +                    insn->src_reg == BPF_PSEUDO_MAP_IDX_VALUE)) {
> 
> Is there a selftest for BPF_PSEUDO_MAP_IDX_VALUE part ?
> I couldn't find it.

Do you mean add a selftest with 'bpftool gen skeleton -L'?

Indeed, it's better to test it.

Thanks,
Leon