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 #include <stdbool.h>
6 
7 #ifdef ENABLE_ATOMICS_TESTS
8 bool skip_tests __attribute((__section__(".data"))) = false;
9 #else
10 bool skip_tests = true;
11 #endif
12 
13 SEC("fentry/bpf_fentry_test1")
14 int BPF_PROG(sub, int x)
15 {
16 #ifdef ENABLE_ATOMICS_TESTS
17 	int a = 0;
18 	int b = __sync_fetch_and_add(&a, 1);
19 	/* b is certainly 0 here. Can the verifier tell? */
20 	while (b)
21 		continue;
22 #endif
23 	return 0;
24 }
25