Re: [PATCH v4 perf,bpf 15/15] perf, bpf: save information about short living bpf programs

From: Jiri Olsa
Date: Wed Feb 27 2019 - 08:21:22 EST


On Mon, Feb 25, 2019 at 04:20:19PM -0800, Song Liu wrote:

SNIP

> + btf_id = info_linear->info.btf_id;
> +
> + info_node = malloc(sizeof(struct bpf_prog_info_node));
> + if (info_node) {
> + info_node->info_linear = info_linear;
> + perf_env__insert_bpf_prog_info(env, info_node);
> + } else
> + free(info_linear);
> +
> + if (btf_id == 0)
> + goto out;
> +
> + if (btf__get_from_id(btf_id, &btf)) {
> + pr_debug("%s: failed to get BTF of id %u, aborting\n",
> + __func__, btf_id);
> + goto out;
> + }
> + perf_env__fetch_btf(env, btf_id, btf);

so is this the main reason we are doing this? getting the btf
data for bpf prog ids and store them?

please describe the whole bpf events/features data flow in
changelog as I asked in previous email

thanks,
jirka