On Wed, Mar 16, 2022 at 01:24:09PM +0100, Jiri Olsa wrote: > +static int > +kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link, > + struct pt_regs *regs) > +{ > + int err; > + > + if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) { > + err = 0; > + goto out; > + } That's a heavy hammer. It's ok-ish for now, but would be good to switch to __this_cpu_inc_return(*(prog->active)) at some point. The way fentry/fexit progs do.