Re: [PATCH perf,bpf 2/2] perf, bpf: show BPF program name in print_bpf_prog_info()

From: Song Liu
Date: Thu Mar 14 2019 - 14:29:48 EST




> On Mar 14, 2019, at 11:25 AM, Song Liu <songliubraving@xxxxxx> wrote:
>
> This patch enables showing bpf program name in the header.
>
> Before the patch:
>
> perf report --header-only
> ...
> # bpf_prog_info of id 9
> # bpf_prog_info of id 10
> # bpf_prog_info of id 13
>
> After the patch:
>
> # bpf_prog_info 9: bpf_prog_7be49e3934a125ba
> # bpf_prog_info 10: bpf_prog_2a142ef67aaad174
> # bpf_prog_info 13: bpf_prog_47368425825d7384_task__task_newt
>
> Signed-off-by: Song Liu <songliubraving@xxxxxx>

Please ignore this patch, and use the other PATCH 2/2 with address and
size information instead.

Thanks,
Song

> ---
> tools/perf/util/bpf-event.c | 36 ++++++++++++++++++++++++++++++++++++
> tools/perf/util/bpf-event.h | 10 +++++++++-
> tools/perf/util/header.c | 5 +++--
> 3 files changed, 48 insertions(+), 3 deletions(-)
>
> diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
> index 6e035e08aa2d..dde35a36e2de 100644
> --- a/tools/perf/util/bpf-event.c
> +++ b/tools/perf/util/bpf-event.c
> @@ -433,3 +433,39 @@ int bpf_event__add_sb_event(struct perf_evlist **evlist,
>
> return perf_evlist__add_sb_event(evlist, &attr, bpf_event__sb_cb, env);
> }
> +
> +void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info,
> + struct perf_env *env,
> + FILE *fp)
> +{
> + char name[KSYM_NAME_LEN];
> + struct btf *btf = NULL;
> + u32 sub_prog_cnt, i;
> +
> + sub_prog_cnt = info->nr_jited_ksyms;
> + if (sub_prog_cnt != info->nr_prog_tags ||
> + sub_prog_cnt != info->nr_jited_func_lens)
> + return;
> +
> + if (info->btf_id) {
> + struct btf_node *node;
> +
> + node = perf_env__find_btf(env, info->btf_id);
> + if (node)
> + btf = btf__new((__u8 *)(node->data),
> + node->data_size);
> + }
> +
> + if (sub_prog_cnt == 1) {
> + synthesize_bpf_prog_name(name, KSYM_NAME_LEN, info, btf, 0);
> + fprintf(fp, "# bpf_prog_info %u: %s\n", info->id, name);
> + return;
> + }
> +
> + fprintf(fp, "# bpf_prog_info %u:\n", info->id);
> + for (i = 0; i < sub_prog_cnt; i++) {
> + synthesize_bpf_prog_name(name, KSYM_NAME_LEN, info, btf, i);
> +
> + fprintf(fp, "# \tsub_prog %u: %s\n", i, name);
> + }
> +}
> diff --git a/tools/perf/util/bpf-event.h b/tools/perf/util/bpf-event.h
> index 249909c826e7..4270dfd9cde9 100644
> --- a/tools/perf/util/bpf-event.h
> +++ b/tools/perf/util/bpf-event.h
> @@ -38,7 +38,9 @@ int perf_event__synthesize_bpf_events(struct perf_session *session,
> struct record_opts *opts);
> int bpf_event__add_sb_event(struct perf_evlist **evlist,
> struct perf_env *env);
> -
> +void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info,
> + struct perf_env *env,
> + FILE *fp);
> #else
> static inline int machine__process_bpf_event(struct machine *machine __maybe_unused,
> union perf_event *event __maybe_unused,
> @@ -61,5 +63,11 @@ static int bpf_event__add_sb_event(struct perf_evlist **evlist __maybe_unused,
> return 0;
> }
>
> +void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info,
> + struct perf_env *env,
> + FILE *fp)
> +{
> +
> +}
> #endif // HAVE_LIBBPF_SUPPORT
> #endif
> diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
> index 7decd2d1dbda..588a80bdd500 100644
> --- a/tools/perf/util/header.c
> +++ b/tools/perf/util/header.c
> @@ -1434,8 +1434,9 @@ static void print_bpf_prog_info(struct feat_fd *ff, FILE *fp)
>
> node = rb_entry(next, struct bpf_prog_info_node, rb_node);
> next = rb_next(&node->rb_node);
> - fprintf(fp, "# bpf_prog_info of id %u\n",
> - node->info_linear->info.id);
> +
> + bpf_event__print_bpf_prog_info(&node->info_linear->info,
> + env, fp);
> }
>
> up_read(&env->bpf_progs.lock);
> --
> 2.17.1
>