/*
 * Copyright (c) 2006-2024, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2024-01-17     Shell        the first version
 */
#include <rtthread.h>
#include <stdlib.h>
#include "utest.h"

/**
 * Stressful Test for Mutex
 */

#define TEST_SECONDS 30
#define TEST_LOOP_TICKS (TEST_SECONDS * RT_TICK_PER_SECOND)
#define TEST_THREAD_COUNTS (RT_CPUS_NR)
#define TEST_PROGRESS_COUNTS (36)
#define TEST_PROGRESS_ON (TEST_LOOP_TICKS/TEST_PROGRESS_COUNTS)
#define TEST_PRIORITY_HIGHEST (UTEST_THR_PRIORITY+1)
#define TEST_RANDOM_LATENCY_MAX (1000 * 1000)

static struct rt_semaphore _thr_exit_sem;
static rt_atomic_t _progress_counter;
static rt_atomic_t _exit_flag;
static struct rt_mutex _racing_lock;

static void test_thread_entry(void *param)
{
    while (1)
    {
        rt_mutex_take(&_racing_lock, RT_WAITING_FOREVER);
        rt_mutex_release(&_racing_lock);

        if (rt_atomic_load(&_exit_flag))
        {
            break;
        }
    }

    rt_sem_release(&_thr_exit_sem);
}

static void mutex_stress_tc(void)
{
    rt_err_t error;
    rt_thread_t tester;
    const rt_base_t priority_base = TEST_PRIORITY_HIGHEST;

    for (size_t i = 0; i < TEST_THREAD_COUNTS; i++)
    {
        tester = rt_thread_create(
            "tester",
            test_thread_entry,
            (void *)0,
            UTEST_THR_STACK_SIZE,
            priority_base + (i % (RT_THREAD_PRIORITY_MAX - TEST_PRIORITY_HIGHEST)),
            1);

        rt_thread_startup(tester);
    }

    for (size_t i = 0; i < TEST_LOOP_TICKS; i++)
    {
        rt_thread_delay(1);

        if (rt_atomic_add(&_progress_counter, 1) % TEST_PROGRESS_ON == 0)
            uassert_true(1);
    }

    /* trigger exit request for all sub-threads */
    rt_atomic_store(&_exit_flag, 1);

    /* waiting for sub-threads to exit */
    for (size_t i = 0; i < TEST_THREAD_COUNTS; i++)
    {
        error = rt_sem_take(&_thr_exit_sem, RT_WAITING_FOREVER);
        uassert_int_equal(error, RT_EOK);
    }
}

static rt_err_t utest_tc_init(void)
{
    int *pseed = rt_malloc(sizeof(int));
    srand(*(int *)pseed);
    rt_free(pseed);

    rt_sem_init(&_thr_exit_sem, "test", 0, RT_IPC_FLAG_PRIO);
    rt_mutex_init(&_racing_lock, "ipc", RT_IPC_FLAG_PRIO);
    return RT_EOK;
}

static rt_err_t utest_tc_cleanup(void)
{
    rt_sem_detach(&_thr_exit_sem);
    rt_mutex_detach(&_racing_lock);
    return RT_EOK;
}

static void testcase(void)
{
    UTEST_UNIT_RUN(mutex_stress_tc);
}
UTEST_TC_EXPORT(testcase, "testcases.kernel.scheduler.mutex", utest_tc_init, utest_tc_cleanup, TEST_SECONDS);