LXR linux/tools/perf/util/bpf-prologue.h

   1/*
   2 * Copyright (C) 2015, He Kuang <hekuang@huawei.com>
   3 * Copyright (C) 2015, Huawei Inc.
   4 */
   5#ifndef __BPF_PROLOGUE_H
   6#define __BPF_PROLOGUE_H
   7
   8#include <linux/compiler.h>
   9#include <linux/filter.h>
  10#include "probe-event.h"
  11
  12#define BPF_PROLOGUE_MAX_ARGS 3
  13#define BPF_PROLOGUE_START_ARG_REG BPF_REG_3
  14#define BPF_PROLOGUE_FETCH_RESULT_REG BPF_REG_2
  15
  16#ifdef HAVE_BPF_PROLOGUE
  17int bpf__gen_prologue(struct probe_trace_arg *args, int nargs,
  18                      struct bpf_insn *new_prog, size_t *new_cnt,
  19                      size_t cnt_space);
  20#else
  21static inline int
  22bpf__gen_prologue(struct probe_trace_arg *args __maybe_unused,
  23                  int nargs __maybe_unused,
  24                  struct bpf_insn *new_prog __maybe_unused,
  25                  size_t *new_cnt,
  26                  size_t cnt_space __maybe_unused)
  27{
  28        if (!new_cnt)
  29                return -EINVAL;
  30        *new_cnt = 0;
  31        return -ENOTSUP;
  32}
  33#endif
  34#endif /* __BPF_PROLOGUE_H */
  35