tools/testing/selftests/bpf/progs/trace_dummy_st_ops.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/bpf.h>
   3 #include <bpf/bpf_helpers.h>
   4 #include <bpf/bpf_tracing.h>
   5
   6 int val = 0;
   7
   8 SEC("fentry/test_1")
   9 int BPF_PROG(fentry_test_1, __u64 *st_ops_ctx)
  10 {
  11         __u64 state;
  12
  13         /* Read the traced st_ops arg1 which is a pointer */
  14         bpf_probe_read_kernel(&state, sizeof(__u64), (void *)st_ops_ctx);
  15         /* Read state->val */
  16         bpf_probe_read_kernel(&val, sizeof(__u32), (void *)state);
  17
  18         return 0;
  19 }
  20
  21 char _license[] SEC("license") = "GPL";