1*0a210af6SMartin KaFai Lau // SPDX-License-Identifier: GPL-2.0
2*0a210af6SMartin KaFai Lau #include <linux/bpf.h>
3*0a210af6SMartin KaFai Lau #include <bpf/bpf_helpers.h>
4*0a210af6SMartin KaFai Lau #include <bpf/bpf_tracing.h>
5*0a210af6SMartin KaFai Lau 
6*0a210af6SMartin KaFai Lau int val = 0;
7*0a210af6SMartin KaFai Lau 
8*0a210af6SMartin KaFai Lau SEC("fentry/test_1")
BPF_PROG(fentry_test_1,__u64 * st_ops_ctx)9*0a210af6SMartin KaFai Lau int BPF_PROG(fentry_test_1, __u64 *st_ops_ctx)
10*0a210af6SMartin KaFai Lau {
11*0a210af6SMartin KaFai Lau 	__u64 state;
12*0a210af6SMartin KaFai Lau 
13*0a210af6SMartin KaFai Lau 	/* Read the traced st_ops arg1 which is a pointer */
14*0a210af6SMartin KaFai Lau 	bpf_probe_read_kernel(&state, sizeof(__u64), (void *)st_ops_ctx);
15*0a210af6SMartin KaFai Lau 	/* Read state->val */
16*0a210af6SMartin KaFai Lau 	bpf_probe_read_kernel(&val, sizeof(__u32), (void *)state);
17*0a210af6SMartin KaFai Lau 
18*0a210af6SMartin KaFai Lau 	return 0;
19*0a210af6SMartin KaFai Lau }
20*0a210af6SMartin KaFai Lau 
21*0a210af6SMartin KaFai Lau char _license[] SEC("license") = "GPL";
22