add context switch test code

Author: rcitach

examples/utest/testcases/Kconfig

@@ -17,6 +17,7 @@ rsource "posix/Kconfig"
 rsource "mm/Kconfig"
 rsource "tmpfs/Kconfig"
 rsource "smp_call/Kconfig"
+rsource "pref/Kconfig"
 endif
 
 endmenu

examples/utest/testcases/pref/Kconfig

@@ -0,0 +1,24 @@
+menu "System Performance Testcase"
+
+config UTEST_SYS_PREF_TC
+    bool "system performance test"
+    default n
+
+choice
+    prompt "Select time reference for System Performance Testcase"
+    default USING_TICK_AS_TIME_REF
+    depends on UTEST_SYS_PREF_TC
+    config USING_HWTIME_AS_TIME_REF
+        bool "Use hardware timer as time reference"
+        depends on RT_USING_HWTIMER
+
+    config USING_TICK_AS_TIME_REF
+        bool "Use system tick as time reference"
+        default y
+endchoice
+
+config UTEST_SYS_CONTEXT_SWITCH
+    bool "system context switch test"
+    default n
+
+endmenu

examples/utest/testcases/pref/SConscript

@@ -0,0 +1,13 @@
+Import('rtconfig')
+from building import *
+
+cwd     = GetCurrentDir()
+src     = []
+CPPPATH = [cwd]
+
+if GetDepend(['UTEST_SYS_CONTEXT_SWITCH']):
+    src += ['context_switch.c']
+
+group = DefineGroup('utestcases', src, depend = ['UTEST_SYS_PREF_TC'], CPPPATH = CPPPATH)
+
+Return('group')

examples/utest/testcases/pref/context_switch.c

@@ -0,0 +1,165 @@
+#include <rtthread.h>
+#include <rthw.h>
+#include <rtdevice.h>
+
+// 定义信号量
+static rt_sem_t sem1, sem2;
+
+// 定义线程控制块
+static rt_thread_t thread1, thread2;
+#define THREAD_STACK_SIZE       1024
+#define THREAD_PRIORITY         10
+#define THREAD_TIMESLICE        5
+
+// 记录切换次数
+#define SWITCH_COUNT 1000
+
+#ifdef RT_USING_HWTIMER
+#define HWTIMER_DEV_NAME   "timer0"     /* 定时器名称 */
+static rt_device_t hw_dev = RT_NULL;
+
+// 获取当前时间（微秒）
+static rt_size_t get_timer_us(rt_hwtimerval_t *timeout_s)
+{
+    if (hw_dev)
+        return rt_device_read(hw_dev, 0, timeout_s, sizeof(rt_hwtimerval_t));
+    return 0;
+}
+#endif
+
+// 线程1入口函数
+static void thread1_entry(void *parameter)
+{
+    while (1)
+    {
+        rt_sem_take(sem1, RT_WAITING_FOREVER); // 获取信号量1
+        rt_sem_release(sem2);                  // 释放信号量2
+    }
+}
+
+// 线程2入口函数
+static void thread2_entry(void *parameter)
+{
+    rt_uint32_t total_time = 0;
+    rt_uint32_t sem_op_time = 0;
+    rt_uint32_t i;
+#ifdef RT_USING_HWTIMER
+    rt_hwtimerval_t start_time, end_time;
+    rt_uint16_t ret;
+    // 测量信号量操作时间（单次获取+释放）
+    ret = get_timer_us(&start_time);
+    for (i = 0; i < SWITCH_COUNT; i++)
+    {
+        rt_sem_take(sem2, RT_WAITING_FOREVER);
+        rt_sem_release(sem2);
+    }
+    ret +=get_timer_us(&end_time);
+    sem_op_time = (end_time.sec - start_time.sec) * 1000 + (end_time.usec - start_time.usec); // 转换为微秒
+
+    // 测量上下文切换总时间
+    ret += get_timer_us(&start_time);
+    for (i = 0; i < SWITCH_COUNT; i++)
+    {
+        rt_sem_take(sem2, RT_WAITING_FOREVER); // 获取信号量2
+        rt_sem_release(sem1);                  // 释放信号量1
+    }
+    ret +=get_timer_us(&end_time);
+    total_time = (end_time.sec - start_time.sec) * 1000 + (end_time.usec - start_time.usec); // 转换为微秒
+
+    if(hw_dev)
+        rt_device_close(hw_dev);
+
+#else
+    rt_uint32_t start_time, end_time;
+    start_time = rt_tick_get();
+    for (i = 0; i < SWITCH_COUNT; i++)
+    {
+        rt_sem_take(sem2, RT_WAITING_FOREVER);
+        rt_sem_release(sem2);
+    }
+    end_time = rt_tick_get();
+    sem_op_time = (end_time - start_time) * (1000u / RT_TICK_PER_SECOND) * 1000u;
+    start_time = rt_tick_get();
+    for (i = 0; i < SWITCH_COUNT; i++)
+    {
+       rt_sem_take(sem2, RT_WAITING_FOREVER); // 获取信号量2
+       rt_sem_release(sem1);                  // 释放信号量1
+    }
+    end_time = rt_tick_get();
+    total_time = (end_time - start_time) * (1000u / RT_TICK_PER_SECOND) * 1000u;
+#endif
+
+    // 计算单次上下文切换时间
+    rt_uint32_t single_switch_time = total_time / SWITCH_COUNT; // 单次切换总时间
+    rt_uint32_t single_sem_op_time = sem_op_time / SWITCH_COUNT; // 单次信号量操作时间
+    rt_uint32_t context_switch_time = single_switch_time - single_sem_op_time; // 上下文切换时间
+
+    // 打印结果
+    rt_kprintf("Total time for %d switches: %d us\n", SWITCH_COUNT, total_time);
+    rt_kprintf("Single switch time (including semaphore): %d us\n", single_switch_time);
+    rt_kprintf("Semaphore operation time: %d us\n", single_sem_op_time);
+    rt_kprintf("Pure context switch time: %d us\n", context_switch_time);
+}
+
+// 初始化测试
+int context_switch_test(void)
+{
+    int ret = RT_EOK;
+#ifdef RT_USING_HWTIMER
+    rt_hwtimerval_t timeout_s;      /* 定时器超时值 */
+
+    hw_dev = rt_device_find(HWTIMER_DEV_NAME);
+    if (hw_dev == RT_NULL)
+    {
+        ret = RT_ERROR;
+        rt_kprintf("hwtimer sample run failed! can't find %s device!\n", HWTIMER_DEV_NAME);
+        return ret;
+    }
+
+    /* 以读写方式打开设备 */
+    ret = rt_device_open(hw_dev, RT_DEVICE_OFLAG_RDWR);
+    if (ret != RT_EOK)
+    {
+        rt_kprintf("open %s device failed!\n", HWTIMER_DEV_NAME);
+        return ret;
+    }
+
+    /* 设置定时器超时值为5s并启动定时器 */
+    timeout_s.sec  = 5;      /* 秒  */
+    timeout_s.usec = 0;     /* 微秒 */
+    if (rt_device_write(hw_dev, 0, &timeout_s, sizeof(rt_hwtimerval_t)) != sizeof(rt_hwtimerval_t))
+    {
+        ret = RT_ERROR;
+        rt_kprintf("set timeout value failed\n");
+        return ret;
+    }
+#endif
+    // 创建信号量
+    sem1 = rt_sem_create("sem1", 1, RT_IPC_FLAG_FIFO); // 初始值为1
+    sem2 = rt_sem_create("sem2", 0, RT_IPC_FLAG_FIFO); // 初始值为0
+    if (sem1 == RT_NULL || sem2 == RT_NULL)
+    {
+        ret = RT_ERROR;
+        rt_kprintf("Semaphore create failed!\n");
+        return ret;
+    }
+
+    // 创建线程1
+    thread1 = rt_thread_create("thread1", thread1_entry, RT_NULL, THREAD_STACK_SIZE, THREAD_PRIORITY, THREAD_TIMESLICE);
+    if (thread1 != RT_NULL)
+    {
+        rt_thread_startup(thread1);
+    }
+    // 创建线程2
+    thread2 = rt_thread_create("thread2", thread2_entry, RT_NULL, THREAD_STACK_SIZE, THREAD_PRIORITY, THREAD_TIMESLICE);
+    if (thread2 != RT_NULL)
+    {
+        rt_thread_startup(thread2);
+    }
+    return ret;
+}
+
+#ifdef RT_USING_FINSH
+#include <finsh.h>
+MSH_CMD_EXPORT(context_switch_test, "Test context switch time");
+#endif