Commit b80b033b authored by Song Liu's avatar Song Liu Committed by Daniel Borkmann
Browse files

bpf: Allow bpf_perf_event_read_value in all BPF programs 



bpf_perf_event_read_value() is NMI safe. Enable it for all BPF programs.
This can be used in fentry/fexit to profile BPF program and individual
kernel function with hardware counters.

Signed-off-by: default avatarSong Liu <songliubraving@fb.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200214234146.2910011-1-songliubraving@fb.com
parent b182a667

kernel/trace/bpf_trace.c

+2 −2
Original line number Diff line number Diff line
@@ -843,6 +843,8 @@ tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 
		return &bpf_send_signal_proto;

	case BPF_FUNC_send_signal_thread:

		return &bpf_send_signal_thread_proto;

	case BPF_FUNC_perf_event_read_value:

		return &bpf_perf_event_read_value_proto;

	default:

		return NULL;

	}
@@ -858,8 +860,6 @@ kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 
		return &bpf_get_stackid_proto;

	case BPF_FUNC_get_stack:

		return &bpf_get_stack_proto;

	case BPF_FUNC_perf_event_read_value:

		return &bpf_perf_event_read_value_proto;

#ifdef CONFIG_BPF_KPROBE_OVERRIDE

	case BPF_FUNC_override_return:

		return &bpf_override_return_proto;

CRA Git | Maintained and supported by SUSTech CRA and CCSE