1#define _GNU_SOURCE
2#include <linux/membarrier.h>
3#include <syscall.h>
4#include <stdio.h>
5#include <errno.h>
6#include <string.h>
7
8#include "../kselftest.h"
9
10enum test_membarrier_status {
11	TEST_MEMBARRIER_PASS = 0,
12	TEST_MEMBARRIER_FAIL,
13	TEST_MEMBARRIER_SKIP,
14};
15
16static int sys_membarrier(int cmd, int flags)
17{
18	return syscall(__NR_membarrier, cmd, flags);
19}
20
21static enum test_membarrier_status test_membarrier_cmd_fail(void)
22{
23	int cmd = -1, flags = 0;
24
25	if (sys_membarrier(cmd, flags) != -1) {
26		printf("membarrier: Wrong command should fail but passed.\n");
27		return TEST_MEMBARRIER_FAIL;
28	}
29	return TEST_MEMBARRIER_PASS;
30}
31
32static enum test_membarrier_status test_membarrier_flags_fail(void)
33{
34	int cmd = MEMBARRIER_CMD_QUERY, flags = 1;
35
36	if (sys_membarrier(cmd, flags) != -1) {
37		printf("membarrier: Wrong flags should fail but passed.\n");
38		return TEST_MEMBARRIER_FAIL;
39	}
40	return TEST_MEMBARRIER_PASS;
41}
42
43static enum test_membarrier_status test_membarrier_success(void)
44{
45	int cmd = MEMBARRIER_CMD_SHARED, flags = 0;
46
47	if (sys_membarrier(cmd, flags) != 0) {
48		printf("membarrier: Executing MEMBARRIER_CMD_SHARED failed. %s.\n",
49				strerror(errno));
50		return TEST_MEMBARRIER_FAIL;
51	}
52
53	printf("membarrier: MEMBARRIER_CMD_SHARED success.\n");
54	return TEST_MEMBARRIER_PASS;
55}
56
57static enum test_membarrier_status test_membarrier(void)
58{
59	enum test_membarrier_status status;
60
61	status = test_membarrier_cmd_fail();
62	if (status)
63		return status;
64	status = test_membarrier_flags_fail();
65	if (status)
66		return status;
67	status = test_membarrier_success();
68	if (status)
69		return status;
70	return TEST_MEMBARRIER_PASS;
71}
72
73static enum test_membarrier_status test_membarrier_query(void)
74{
75	int flags = 0, ret;
76
77	printf("membarrier MEMBARRIER_CMD_QUERY ");
78	ret = sys_membarrier(MEMBARRIER_CMD_QUERY, flags);
79	if (ret < 0) {
80		printf("failed. %s.\n", strerror(errno));
81		switch (errno) {
82		case ENOSYS:
83			/*
84			 * It is valid to build a kernel with
85			 * CONFIG_MEMBARRIER=n. However, this skips the tests.
86			 */
87			return TEST_MEMBARRIER_SKIP;
88		case EINVAL:
89		default:
90			return TEST_MEMBARRIER_FAIL;
91		}
92	}
93	if (!(ret & MEMBARRIER_CMD_SHARED)) {
94		printf("command MEMBARRIER_CMD_SHARED is not supported.\n");
95		return TEST_MEMBARRIER_FAIL;
96	}
97	printf("syscall available.\n");
98	return TEST_MEMBARRIER_PASS;
99}
100
101int main(int argc, char **argv)
102{
103	switch (test_membarrier_query()) {
104	case TEST_MEMBARRIER_FAIL:
105		return ksft_exit_fail();
106	case TEST_MEMBARRIER_SKIP:
107		return ksft_exit_skip();
108	}
109	switch (test_membarrier()) {
110	case TEST_MEMBARRIER_FAIL:
111		return ksft_exit_fail();
112	case TEST_MEMBARRIER_SKIP:
113		return ksft_exit_skip();
114	}
115
116	printf("membarrier: tests done!\n");
117	return ksft_exit_pass();
118}
119