xref: /third_party/ltp/testcases/kernel/syscalls/futex/futex_wait02.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2015 Cyril Hrubis <chrubis@suse.cz>
 *
 * Block on a futex and wait for wakeup.
 *
 * This tests uses shared memory page to store the mutex variable.
 */

#include <sys/mman.h>
#include <sys/wait.h>

#include "futextest.h"
#include "futex_utils.h"

static futex_t *futex;

static struct futex_test_variants variants[] = {
#if (__NR_futex != __LTP__NR_INVALID_SYSCALL)
	{ .fntype = FUTEX_FN_FUTEX, .desc = "syscall with old kernel spec"},
#endif

#if (__NR_futex_time64 != __LTP__NR_INVALID_SYSCALL)
	{ .fntype = FUTEX_FN_FUTEX64, .desc = "syscall time64 with kernel spec"},
#endif
};

static void do_child(void)
{
	struct futex_test_variants *tv = &variants[tst_variant];
	int ret;

	TST_PROCESS_STATE_WAIT(getppid(), 'S', 1000);

	ret = futex_wake(tv->fntype, futex, 1, 0);

	if (ret != 1)
		tst_res(TFAIL | TERRNO, "futex_wake() failed");

	exit(0);
}

static void run(void)
{
	struct futex_test_variants *tv = &variants[tst_variant];
	int res, pid;

	pid = SAFE_FORK();
	if (!pid)
		do_child();

	res = futex_wait(tv->fntype, futex, *futex, NULL, 0);
	if (res) {
		tst_res(TFAIL | TERRNO, "futex_wait() failed");
		return;
	}

	SAFE_WAIT(NULL);
	tst_res(TPASS, "futex_wait() woken up");
}

static void setup(void)
{
	struct futex_test_variants *tv = &variants[tst_variant];

	tst_res(TINFO, "Testing variant: %s", tv->desc);
	futex_supported_by_kernel(tv->fntype);

	futex = SAFE_MMAP(NULL, sizeof(*futex), PROT_READ | PROT_WRITE,
			  MAP_ANONYMOUS | MAP_SHARED, -1, 0);

	*futex = FUTEX_INITIALIZER;
}

static struct tst_test test = {
	.setup = setup,
	.test_all = run,
	.test_variants = ARRAY_SIZE(variants),
	.forks_child = 1,
};