C++ set_sys_tune函数代码示例

void cleanup(void)
{
	set_sys_tune("overcommit_memory", old_overcommit, 0);
	set_sys_tune("max_map_count", old_max_map_count, 0);

	TEST_CLEANUP;
}

static void overcommit_memory_test(void)
{

#if __WORDSIZE == 32
	tst_brk(TCONF, "test is not designed for 32-bit system.");
#endif
	/* start to test overcommit_memory=2 */
	set_sys_tune("overcommit_memory", 2, 1);

	update_mem_commit();
	alloc_and_check(commit_left * 2, EXPECT_FAIL);
	alloc_and_check(commit_limit, EXPECT_FAIL);
	update_mem_commit();
	alloc_and_check(commit_left / 2, EXPECT_PASS);

	/* start to test overcommit_memory=0 */
	set_sys_tune("overcommit_memory", 0, 1);

	update_mem();
	alloc_and_check(free_total / 2, EXPECT_PASS);
	update_mem();
	alloc_and_check(free_total * 2, EXPECT_FAIL);
	alloc_and_check(sum_total, EXPECT_FAIL);

	/* start to test overcommit_memory=1 */
	set_sys_tune("overcommit_memory", 1, 1);

	alloc_and_check(sum_total / 2, EXPECT_PASS);
	alloc_and_check(sum_total, EXPECT_PASS);
	alloc_and_check(sum_total * 2, EXPECT_PASS);

}

static void cleanup(void)
{
	if (old_overcommit_memory != -1)
		set_sys_tune("overcommit_memory", old_overcommit_memory, 0);
	if (old_overcommit_ratio != -1)
		set_sys_tune("overcommit_ratio", old_overcommit_ratio, 0);
}

int main(int argc, char *argv[])
{
	int lc;

	tst_parse_opts(argc, argv, NULL, NULL);

#if __WORDSIZE == 32
	tst_brkm(TCONF, NULL, "test is not designed for 32-bit system.");
#endif

	setup();

	for (lc = 0; TEST_LOOPING(lc); lc++) {
		tst_count = 0;

		/* we expect mmap to fail before OOM is hit */
		set_sys_tune("overcommit_memory", 2, 1);
		oom(OVERCOMMIT, 0, ENOMEM, 0);

		/* with overcommit_memory set to 0 or 1 there's no
		 * guarantee that mmap fails before OOM */
		set_sys_tune("overcommit_memory", 0, 1);
		oom(OVERCOMMIT, 0, ENOMEM, 1);

		set_sys_tune("overcommit_memory", 1, 1);
		testoom(0, 0, ENOMEM, 1);
	}
	cleanup();
	tst_exit();
}

void cleanup(void)
{
	set_sys_tune("overcommit_memory", old_overcommit_memory, 0);
	set_sys_tune("overcommit_ratio", old_overcommit_ratio, 0);

	TEST_CLEANUP;
}

static void overcommit_memory_test(void)
{
	/* start to test overcommit_memory=2 */
	set_sys_tune("overcommit_memory", 2, 1);

	update_mem();
	alloc_and_check(commit_left * 2, EXPECT_FAIL);
	alloc_and_check(commit_limit, EXPECT_FAIL);
	update_mem();
	alloc_and_check(commit_left / 2, EXPECT_PASS);

	/* start to test overcommit_memory=0 */
	set_sys_tune("overcommit_memory", 0, 1);

	update_mem();
	alloc_and_check(free_total / 2, EXPECT_PASS);
	update_mem();
	alloc_and_check(free_total * 2, EXPECT_FAIL);
	alloc_and_check(sum_total, EXPECT_FAIL);

	/* start to test overcommit_memory=1 */
	set_sys_tune("overcommit_memory", 1, 1);

	alloc_and_check(sum_total / 2, EXPECT_PASS);
	alloc_and_check(sum_total, EXPECT_PASS);
	alloc_and_check(sum_total * 2, EXPECT_PASS);

}

void setup(void)
{
	long hpage_size;

	tst_require_root();
	check_hugepage();
	tst_sig(FORK, DEF_HANDLER, cleanup);
	tst_tmpdir();

	orig_hugepages = get_sys_tune("nr_hugepages");
	set_sys_tune("nr_hugepages", hugepages, 1);
	hpage_size = read_meminfo("Hugepagesize:") * 1024;

	shm_size = hpage_size * hugepages / 2;
	update_shm_size(&shm_size);
	shmkey = getipckey(cleanup);
	shm_id_1 = shmget(shmkey, shm_size,
			  SHM_HUGETLB | IPC_CREAT | IPC_EXCL | SHM_RW);
	if (shm_id_1 == -1)
		tst_brkm(TBROK | TERRNO, cleanup, "shmget");

	/* get the userid for a non root user */
	ltp_uid = getuserid(cleanup, ltp_user);

	TEST_PAUSE;
}

void setup(void)
{
	int ret, memnode;

	tst_require_root();
	tst_sig(FORK, DEF_HANDLER, cleanup);
	TEST_PAUSE;

	if (!is_numa(NULL, NH_MEMS, 1))
		tst_brkm(TCONF, NULL, "requires NUMA with at least 1 node");

	overcommit = get_sys_tune("overcommit_memory");
	set_sys_tune("overcommit_memory", 1, 1);

	mount_mem("memcg", "cgroup", "memory", MEMCG_PATH, MEMCG_PATH_NEW);
	mount_mem("cpuset", "cpuset", NULL, CPATH, CPATH_NEW);
	write_memcg();

	/*
	 * Some nodes do not contain memory, so use
	 * get_allowed_nodes(NH_MEMS) to get a memory
	 * node. This operation also applies to Non-NUMA
	 * systems.
	 */
	ret = get_allowed_nodes(NH_MEMS, 1, &memnode);
	if (ret < 0)
		tst_brkm(TBROK, cleanup, "Failed to get a memory node "
				      "using get_allowed_nodes()");
	write_cpusets(memnode);
}

void setup(void)
{
	long hpage_size;

	tst_require_root(NULL);
	tst_sig(NOFORK, DEF_HANDLER, cleanup);
	tst_tmpdir();

	orig_hugepages = get_sys_tune("nr_hugepages");
	set_sys_tune("nr_hugepages", hugepages, 1);
	hpage_size = read_meminfo("Hugepagesize:") * 1024;

	shm_size = hpage_size * hugepages / 2;
	update_shm_size(&shm_size);
	shmkey = getipckey();

	/* create a shared memory segment without read or write permissions */
	shm_id_1 = shmget(shmkey, shm_size, SHM_HUGETLB | IPC_CREAT | IPC_EXCL);
	if (shm_id_1 == -1)
		tst_brkm(TBROK | TERRNO, cleanup, "shmget #1");

	/* create a shared memory segment with read and write permissions */
	shm_id_2 = shmget(shmkey + 1, shm_size,
			  SHM_HUGETLB | IPC_CREAT | IPC_EXCL | SHM_RW);
	if (shm_id_2 == -1)
		tst_brkm(TBROK | TERRNO, cleanup, "shmget #2");

	TEST_PAUSE;
}

void setup(void)
{
	long mem_total, hpage_size;

	tst_require_root();

	mem_total = read_meminfo("MemTotal:");
	SAFE_FILE_SCANF(NULL, PATH_SHMMAX, "%ld", &orig_shmmax);
	SAFE_FILE_PRINTF(NULL, PATH_SHMMAX, "%ld", (long)SIZE);
	SAFE_FILE_SCANF(NULL, PATH_SHMMAX, "%ld", &new_shmmax);

	if (mem_total < 2L*1024*1024)
		tst_brkm(TCONF,	NULL, "Needed > 2GB RAM, have: %ld", mem_total);

	if (new_shmmax < SIZE)
		tst_brkm(TCONF,	NULL, "shmmax too low, have: %ld", new_shmmax);

	orig_hugepages = get_sys_tune("nr_hugepages");
	hpage_size = read_meminfo("Hugepagesize:") * 1024;

	hugepages = (orig_hugepages * hpage_size + SIZE) / hpage_size;
	set_sys_tune("nr_hugepages", hugepages, 1);

	TEST_PAUSE;
}

void setup(void)
{
	long hpage_size;

	tst_require_root(NULL);
	tst_sig(NOFORK, sighandler, cleanup);
	tst_tmpdir();

	orig_hugepages = get_sys_tune("nr_hugepages");
	set_sys_tune("nr_hugepages", hugepages, 1);
	hpage_size = read_meminfo("Hugepagesize:") * 1024;

	shm_size = hpage_size * hugepages / 2;
	update_shm_size(&shm_size);
	shmkey = getipckey();

	/* create a shared memory resource with read and write permissions */
	shm_id_1 = shmget(shmkey, shm_size,
			  SHM_HUGETLB | SHM_RW | IPC_CREAT | IPC_EXCL);
	if (shm_id_1 == -1)
		tst_brkm(TBROK | TERRNO, cleanup, "shmget");

	/* attach the shared memory segment */
	shared = shmat(shm_id_1, 0, 0);
	if (shared == (void *)-1)
		tst_brkm(TBROK | TERRNO, cleanup, "shmat #1");

	/* give a value to the shared memory integer */
	*shared = 4;

	TEST_PAUSE;
}

static void setup(void)
{
	int memnode, ret;

	if (!is_numa(NULL, NH_MEMS, 1))
		tst_brk(TCONF, "requires NUMA with at least 1 node");

	overcommit = get_sys_tune("overcommit_memory");
	set_sys_tune("overcommit_memory", 1, 1);

	mount_mem("cpuset", "cpuset", NULL, CPATH, CPATH_NEW);
	cpuset_mounted = 1;

	/*
	 * Some nodes do not contain memory, so use
	 * get_allowed_nodes(NH_MEMS) to get a memory
	 * node. This operation also applies to Non-NUMA
	 * systems.
	 */
	ret = get_allowed_nodes(NH_MEMS, 1, &memnode);
	if (ret < 0)
		tst_brk(TBROK, "Failed to get a memory node "
			      "using get_allowed_nodes()");
	write_cpusets(memnode);
}

void setup(void)
{
	int memnode, ret;

	tst_require_root(NULL);
	tst_sig(FORK, DEF_HANDLER, cleanup);
	TEST_PAUSE;

	overcommit = get_sys_tune("overcommit_memory");
	set_sys_tune("overcommit_memory", 1, 1);

	mount_mem("cpuset", "cpuset", NULL, CPATH, CPATH_NEW);

	/*
	 * Some nodes do not contain memory, so use
	 * get_allowed_nodes(NH_MEMS) to get a memory
	 * node. This operation also applies to Non-NUMA
	 * systems.
	 */
	ret = get_allowed_nodes(NH_MEMS, 1, &memnode);
	if (ret < 0)
		tst_brkm(TBROK, NULL, "Failed to get a memory node "
				      "using get_allowed_nodes()");
	write_cpusets(memnode);
}

void cleanup(void)
{
	set_sys_tune("overcommit_memory", overcommit, 0);
	umount_mem(CPATH, CPATH_NEW);

	TEST_CLEANUP;
}

void setup(void)
{
	long mem_total, swap_total;

	tst_require_root(NULL);

	tst_sig(NOFORK, DEF_HANDLER, cleanup);

	TEST_PAUSE;

	if (access(PATH_SYSVM "overcommit_memory", F_OK) == -1 ||
	    access(PATH_SYSVM "overcommit_ratio", F_OK) == -1)
		tst_brkm(TCONF, NULL, "The system "
			 "can't support to test %s", TCID);

	old_overcommit_memory = get_sys_tune("overcommit_memory");
	old_overcommit_ratio = get_sys_tune("overcommit_ratio");

	set_sys_tune("overcommit_ratio", overcommit_ratio, 1);

	mem_total = read_meminfo("MemTotal:");
	tst_resm(TINFO, "MemTotal is %ld kB", mem_total);
	swap_total = read_meminfo("SwapTotal:");
	tst_resm(TINFO, "SwapTotal is %ld kB", swap_total);
	sum_total = mem_total + swap_total;

	commit_limit = read_meminfo("CommitLimit:");
	tst_resm(TINFO, "CommitLimit is %ld kB", commit_limit);
}