From e2b2cd592adbd303bcc02451d32fedd511000fb0 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 20 Sep 2023 23:31:38 +0200 Subject: [PATCH] bpf: Add missed value to kprobe_multi link info Add missed value to kprobe_multi link info to hold the stats of missed kprobe_multi probe. The missed counter gets incremented when fprobe fails the recursion check or there's no rethook available for return probe. In either case the attached bpf program is not executed. Signed-off-by: Jiri Olsa Signed-off-by: Andrii Nakryiko Tested-by: Song Liu Reviewed-by: Song Liu Acked-by: Hou Tao Link: https://lore.kernel.org/bpf/20230920213145.1941596-3-jolsa@kernel.org --- include/uapi/linux/bpf.h | 1 + kernel/trace/bpf_trace.c | 1 + tools/include/uapi/linux/bpf.h | 1 + 3 files changed, 3 insertions(+) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 5f13db15a3c70..1da5b1bcce710 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -6532,6 +6532,7 @@ struct bpf_link_info { __aligned_u64 addrs; __u32 count; /* in/out: kprobe_multi function count */ __u32 flags; + __u64 missed; } kprobe_multi; struct { __u32 type; /* enum bpf_perf_event_type */ diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 54827d04c9a67..6aec6e7d612ab 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2614,6 +2614,7 @@ static int bpf_kprobe_multi_link_fill_link_info(const struct bpf_link *link, kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link); info->kprobe_multi.count = kmulti_link->cnt; info->kprobe_multi.flags = kmulti_link->flags; + info->kprobe_multi.missed = kmulti_link->fp.nmissed; if (!uaddrs) return 0; diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 5f13db15a3c70..1da5b1bcce710 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -6532,6 +6532,7 @@ struct bpf_link_info { __aligned_u64 addrs; __u32 count; /* in/out: kprobe_multi function count */ __u32 flags; + __u64 missed; } kprobe_multi; struct { __u32 type; /* enum bpf_perf_event_type */ -- 2.30.2