samples/bpf/trace_output_kern.c

   1 #include <linux/ptrace.h>
   2 #include <linux/version.h>
   3 #include <uapi/linux/bpf.h>
   4 #include <bpf/bpf_helpers.h>
   5 #include "trace_common.h"
   6
   7 struct {
   8         __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
   9         __uint(key_size, sizeof(int));
  10         __uint(value_size, sizeof(u32));
  11         __uint(max_entries, 2);
  12 } my_map SEC(".maps");
  13
  14 SEC("kprobe/" SYSCALL(sys_write))
  15 int bpf_prog1(struct pt_regs *ctx)
  16 {
  17         struct S {
  18                 u64 pid;
  19                 u64 cookie;
  20         } data;
  21
  22         data.pid = bpf_get_current_pid_tgid();
  23         data.cookie = 0x12345678;
  24
  25         bpf_perf_event_output(ctx, &my_map, 0, &data, sizeof(data));
  26
  27         return 0;
  28 }
  29
  30 char _license[] SEC("license") = "GPL";
  31 u32 _version SEC("version") = LINUX_VERSION_CODE;