samples/bpf/tracex6_kern.c

   1 #include <linux/ptrace.h>
   2 #include <linux/version.h>
   3 #include <uapi/linux/bpf.h>
   4 #include "bpf_helpers.h"
   5
   6 struct bpf_map_def SEC("maps") my_map = {
   7         .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
   8         .key_size = sizeof(int),
   9         .value_size = sizeof(u32),
  10         .max_entries = 32,
  11 };
  12
  13 SEC("kprobe/sys_write")
  14 int bpf_prog1(struct pt_regs *ctx)
  15 {
  16         u64 count;
  17         u32 key = bpf_get_smp_processor_id();
  18         char fmt[] = "CPU-%d   %llu\n";
  19
  20         count = bpf_perf_event_read(&my_map, key);
  21         bpf_trace_printk(fmt, sizeof(fmt), key, count);
  22
  23         return 0;
  24 }
  25
  26 char _license[] SEC("license") = "GPL";
  27 u32 _version SEC("version") = LINUX_VERSION_CODE;