On Mon, Oct 12, 2026 at 11:40:13PM +0800, Leon Hwang wrote:
SNIP
> @@ -3787,64 +3796,129 @@ static const struct bpf_link_ops
> bpf_tracing_multi_link_lops = {
> #endif
> };
>
> -static int ids_cmp_r(const void *pa, const void *pb, const void *priv
> __maybe_unused)
> +struct tracing_multi_sort_data {
> + u64 *keys;
> + struct bpf_prog **progs;
> + u32 *ids;
> + u64 *cookies;
> +};
> +
> +static int keys_cmp_r(const void *pa, const void *pb, const void *priv
> __maybe_unused)
> {
> - u32 a = *(u32 *) pa;
> - u32 b = *(u32 *) pb;
I think you could just s/32/64/ and keep the rest in here and have simpler diff
> + const u64 *key_a = pa, *key_b = pb;
>
> - return (a > b) - (a < b);
> + return (*key_a > *key_b) - (*key_a < *key_b);
> }
>
> -static void ids_swap_r(void *a, void *b, int size __maybe_unused,
> - const void *priv __maybe_unused)
> +static void keys_swap_r(void *a, void *b, int size __maybe_unused,
> + const void *priv __maybe_unused)
> {
> + const struct tracing_multi_sort_data *data = priv;
> + struct bpf_prog **prog_a, **prog_b;
> u64 *cookie_a, *cookie_b, *cookies;
> - u32 *id_a = a, *id_b = b, *ids;
> - void **data = (void **) priv;
> + u64 *key_a = a, *key_b = b, *keys;
> + u32 *id_a, *id_b, *ids;
> +
> + keys = data->keys;
> + ids = data->ids;
> + cookies = data->cookies;
> + id_a = ids + (key_a - keys);
> + id_b = ids + (key_b - keys);
>
> - ids = data[0];
> - cookies = data[1];
> + if (data->progs) {
nit, let's unify with the rest of the code and have progs variable for
data->progs ?
SNIP
> - err = check_dup_ids(ids, cookies, cnt);
> + keys = kvmalloc_objs(*keys, cnt);
> + if (!keys) {
> + err = -ENOMEM;
> + goto error;
> + }
> +
> + for (int i = 0; i < cnt; i++)
> + keys[i] = bpf_trampoline_compute_key(progs ? progs[i] : NULL,
> btf, ids[i]);
> +
> + err = check_dup_keys(keys, progs, ids, cookies, cnt);
> if (err)
> goto error;
>
> @@ -3908,19 +4022,32 @@ int bpf_tracing_multi_attach(struct bpf_prog *prog,
> const union bpf_attr *attr)
> link->nodes_cnt = cnt;
> link->cookies = cookies;
> link->fexits = fexits;
> + link->tgt_progs = progs;
> + link->pokes = pokes;
>
> - err = bpf_trampoline_multi_attach(prog, ids, link);
> + if (progs)
> + err = bpf_trampoline_multi_prog_attach(prog, ids, keys, link);
you need keys computed ahead for dups check, so let's the above
bpf_trampoline_compute_key calls be the single place we compute keys
and pass keys to bpf_trampoline_multi_attach below as well?
> + else
> + err = bpf_trampoline_multi_attach(prog, ids, link);
nit, let's add empty line in here?
> kvfree(ids);
> + kvfree(keys);
> + kvfree(fds);
> if (err) {
> + bpf_put_progs(progs, cnt);
> bpf_link_cleanup(&link_primer);
> return err;
> }
> return bpf_link_settle(&link_primer);
thanks,
jirka
