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}