Re: [PATCH v8 bpf-next 09/10] bpf: Add kfunc filter function to 'struct btf_kfunc_id_set'

[Martin KaFai Lau <martin.lau@linux.dev>]

On 5/17/23 10:59 AM, Aditi Ghag wrote:
>   static int btf_populate_kfunc_set(struct btf *btf, enum btf_kfunc_hook hook,
> -				  struct btf_id_set8 *add_set)
> +				  const struct btf_kfunc_id_set *kset)
>   {
> +	struct btf_kfunc_hook_filter *hook_filter;
> +	struct btf_id_set8 *add_set = kset->set;
>   	bool vmlinux_set = !btf_is_module(btf);
> +	bool add_filter = !!kset->filter;
>   	struct btf_kfunc_set_tab *tab;
>   	struct btf_id_set8 *set;
>   	u32 set_cnt;
> @@ -7737,6 +7747,20 @@ static int btf_populate_kfunc_set(struct btf *btf, enum btf_kfunc_hook hook,
>   		return 0;
>   
>   	tab = btf->kfunc_set_tab;
> +
> +	if (tab && add_filter) {
> +		int i;
> +
> +		hook_filter = &tab->hook_filters[hook];
> +		for (i = 0; i < hook_filter->nr_filters; i++) {
> +			if (hook_filter->filters[i] == kset->filter)
> +				add_filter = false;

Just noticed that this missed a "break;" that can save some unnecessary loops.

It seems it needs to respin one more time to clarify the patch 1 commit message. 
Please also move patch 9 before patch 6 adding the 'bpf: Add bpf_sock_destroy 
kfunc'. Patch 6 requires patch 9 to be safe. Then the patch 10 selftests can be 
combined with patch 8 selftests as the last patch of the set.

Others lgtm.

> +		}
> +
> +		if (add_filter && hook_filter->nr_filters == BTF_KFUNC_FILTER_MAX_CNT)
> +			return -E2BIG;
> +	}
> +
>   	if (!tab) {
>   		tab = kzalloc(sizeof(*tab), GFP_KERNEL | __GFP_NOWARN);
>   		if (!tab)