bpftool: Display missed count for kprobe perf link
Adding 'missed' field to display missed counts for kprobes
attached by perf event link, like:
# bpftool link
5: perf_event prog 82
kprobe
ffffffff815203e0 ksys_write
6: perf_event prog 83
kprobe
ffffffff811d1e50 scheduler_tick missed 682217
# bpftool link -jp
[{
"id": 5,
"type": "perf_event",
"prog_id": 82,
"retprobe": false,
"addr":
18446744071584220128,
"func": "ksys_write",
"offset": 0,
"missed": 0
},{
"id": 6,
"type": "perf_event",
"prog_id": 83,
"retprobe": false,
"addr":
18446744071580753488,
"func": "scheduler_tick",
"offset": 0,
"missed": 693469
}
]
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-7-jolsa@kernel.org