From: Andrii Nakryiko Date: Mon, 25 Sep 2023 23:37:45 +0000 (-0700) Subject: Merge branch 'bpf: Add missed stats for kprobes' X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=0e73ef1d8c09a1f21ca2b19684819dbbcdce00f9;p=linux.git Merge branch 'bpf: Add missed stats for kprobes' Jiri Olsa says: ==================== hi, at the moment we can't retrieve the number of missed kprobe executions and subsequent execution of BPF programs. This patchset adds: - counting of missed execution on attach layer for: . kprobes attached through perf link (kprobe/ftrace) . kprobes attached through kprobe.multi link (fprobe) - counting of recursion_misses for BPF kprobe programs It's still technically possible to create kprobe without perf link (using SET_BPF perf ioctl) in which case we don't have a way to retrieve the kprobe's 'missed' count. However both libbpf and cilium/ebpf libraries use perf link if it's available, and for old kernels without perf link support we can use BPF program to retrieve the kprobe missed count. v3 changes: - added acks [Song] - make test_missed not serial [Andrii] Also available at: https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git bpf/missed_stats thanks, jirka ==================== Signed-off-by: Andrii Nakryiko --- 0e73ef1d8c09a1f21ca2b19684819dbbcdce00f9