bpftool: Display cookie for perf event link probes

Displaying cookie for perf event link probes, in plain mode:

  # bpftool link
  17: perf_event  prog 90
          kprobe ffffffff82b1c2b0 bpf_fentry_test1  cookie 3735928559
  18: perf_event  prog 90
          kretprobe ffffffff82b1c2b0 bpf_fentry_test1  cookie 3735928559
  20: perf_event  prog 92
          tracepoint sched_switch  cookie 3735928559
  21: perf_event  prog 93
          event software:page-faults  cookie 3735928559
  22: perf_event  prog 91
          uprobe /proc/self/exe+0xd703c  cookie 3735928559

And in json mode:

  # bpftool link -j | jq

  {
    "id": 30,
    "type": "perf_event",
    "prog_id": 160,
    "retprobe": false,
    "addr": 18446744071607272112,
    "func": "bpf_fentry_test1",
    "offset": 0,
    "missed": 0,
    "cookie": 3735928559
  }

  {
    "id": 33,
    "type": "perf_event",
    "prog_id": 162,
    "tracepoint": "sched_switch",
    "cookie": 3735928559
  }

  {
    "id": 34,
    "type": "perf_event",
    "prog_id": 163,
    "event_type": "software",
    "event_config": "page-faults",
    "cookie": 3735928559
  }

  {
    "id": 35,
    "type": "perf_event",
    "prog_id": 161,
    "retprobe": false,
    "file": "/proc/self/exe",
    "offset": 880700,
    "cookie": 3735928559
  }
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240119110505.400573-8-jolsa@kernel.orgSigned-off-by: Alexei Starovoitov <ast@kernel.org>

tools/bpf/bpftool/link.c

@@ -334,6 +334,7 @@ show_perf_event_kprobe_json(struct bpf_link_info *info, json_writer_t *wtr)
 			   u64_to_ptr(info->perf_event.kprobe.func_name));
 	jsonw_uint_field(wtr, "offset", info->perf_event.kprobe.offset);
 	jsonw_uint_field(wtr, "missed", info->perf_event.kprobe.missed);
+	jsonw_uint_field(wtr, "cookie", info->perf_event.kprobe.cookie);
 }
 
 static void
@@ -343,6 +344,7 @@ show_perf_event_uprobe_json(struct bpf_link_info *info, json_writer_t *wtr)
 	jsonw_string_field(wtr, "file",
 			   u64_to_ptr(info->perf_event.uprobe.file_name));
 	jsonw_uint_field(wtr, "offset", info->perf_event.uprobe.offset);
+	jsonw_uint_field(wtr, "cookie", info->perf_event.uprobe.cookie);
 }
 
 static void
@@ -350,6 +352,7 @@ show_perf_event_tracepoint_json(struct bpf_link_info *info, json_writer_t *wtr)
 {
 	jsonw_string_field(wtr, "tracepoint",
 			   u64_to_ptr(info->perf_event.tracepoint.tp_name));
+	jsonw_uint_field(wtr, "cookie", info->perf_event.tracepoint.cookie);
 }
 
 static char *perf_config_hw_cache_str(__u64 config)
@@ -426,6 +429,8 @@ show_perf_event_event_json(struct bpf_link_info *info, json_writer_t *wtr)
 	else
 		jsonw_uint_field(wtr, "event_config", config);
 
+	jsonw_uint_field(wtr, "cookie", info->perf_event.event.cookie);
+
 	if (type == PERF_TYPE_HW_CACHE && perf_config)
 		free((void *)perf_config);
 }
@@ -754,6 +759,8 @@ static void show_perf_event_kprobe_plain(struct bpf_link_info *info)
 		printf("+%#x", info->perf_event.kprobe.offset);
 	if (info->perf_event.kprobe.missed)
 		printf("  missed %llu", info->perf_event.kprobe.missed);
+	if (info->perf_event.kprobe.cookie)
+		printf("  cookie %llu", info->perf_event.kprobe.cookie);
 	printf("  ");
 }
 
@@ -770,6 +777,8 @@ static void show_perf_event_uprobe_plain(struct bpf_link_info *info)
 	else
 		printf("\n\tuprobe ");
 	printf("%s+%#x  ", buf, info->perf_event.uprobe.offset);
+	if (info->perf_event.uprobe.cookie)
+		printf("cookie %llu  ", info->perf_event.uprobe.cookie);
 }
 
 static void show_perf_event_tracepoint_plain(struct bpf_link_info *info)
@@ -781,6 +790,8 @@ static void show_perf_event_tracepoint_plain(struct bpf_link_info *info)
 		return;
 
 	printf("\n\ttracepoint %s  ", buf);
+	if (info->perf_event.tracepoint.cookie)
+		printf("cookie %llu  ", info->perf_event.tracepoint.cookie);
 }
 
 static void show_perf_event_event_plain(struct bpf_link_info *info)
@@ -802,6 +813,9 @@ static void show_perf_event_event_plain(struct bpf_link_info *info)
 	else
 		printf("%llu  ", config);
 
+	if (info->perf_event.event.cookie)
+		printf("cookie %llu  ", info->perf_event.event.cookie);
+
 	if (type == PERF_TYPE_HW_CACHE && perf_config)
 		free((void *)perf_config);
 }