Re: [PATCH bpf-next v11 10/13] bpf, net: switch to dynamic registration

[Martin KaFai Lau <martin.lau@xxxxxxxxx>]

On 11/6/23 12:12 PM, thinker.li@xxxxxxxxx wrote:
> diff --git a/include/linux/bpf.h b/include/linux/bpf.h
> index 48e97a255945..432c088d4001 100644
> --- a/include/linux/bpf.h
> +++ b/include/linux/bpf.h
> @@ -1643,7 +1643,6 @@ struct bpf_struct_ops_desc {
>   #if defined(CONFIG_BPF_JIT) && defined(CONFIG_BPF_SYSCALL)
>   #define BPF_MODULE_OWNER ((void *)((0xeB9FUL << 2) + POISON_POINTER_DELTA))
>   const struct bpf_struct_ops_desc *bpf_struct_ops_find(struct btf *btf, u32 type_id);
> -void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log);
>   bool bpf_struct_ops_get(const void *kdata);
>   void bpf_struct_ops_put(const void *kdata);
>   int bpf_struct_ops_map_sys_lookup_elem(struct bpf_map *map, void *key,
> @@ -1689,10 +1688,6 @@ static inline const struct bpf_struct_ops_desc *bpf_struct_ops_find(struct btf *
>   {
>   	return NULL;
>   }
> -static inline void bpf_struct_ops_init(struct btf *btf,
> -				       struct bpf_verifier_log *log)
> -{
> -}
>   static inline bool bpf_try_module_get(const void *data, struct module *owner)
>   {
>   	return try_module_get(owner);
> @@ -3232,6 +3227,8 @@ static inline bool bpf_is_subprog(const struct bpf_prog *prog)
>   }
>   
>   #ifdef CONFIG_BPF_JIT
> +int register_bpf_struct_ops(struct bpf_struct_ops *st_ops);
> +
>   enum bpf_struct_ops_state {
>   	BPF_STRUCT_OPS_STATE_INIT,
>   	BPF_STRUCT_OPS_STATE_INUSE,
> @@ -3243,6 +3240,23 @@ struct bpf_struct_ops_common_value {
>   	refcount_t refcnt;
>   	enum bpf_struct_ops_state state;
>   };
> +
> +/* bpf_struct_ops_##_name (e.g. bpf_struct_ops_tcp_congestion_ops) is
> + * the map's value exposed to the userspace and its btf-type-id is
> + * stored at the map->btf_vmlinux_value_type_id.
> + *
> + */
> +#define DEFINE_STRUCT_OPS_VALUE_TYPE(_name)			\
> +extern struct bpf_struct_ops bpf_##_name;			\

Is it still needed?

> +								\
> +struct bpf_struct_ops_##_name {					\
> +	struct bpf_struct_ops_common_value common;		\
> +	struct _name data ____cacheline_aligned_in_smp;		\
> +}
> +
> +extern int bpf_struct_ops_desc_init(struct bpf_struct_ops_desc *st_ops_desc,
> +				    struct btf *btf,
> +				    struct bpf_verifier_log *log);

nit. Remove extern.

>   #endif /* CONFIG_BPF_JIT */
>   
>   #endif /* _LINUX_BPF_H */