fix unexpected wakeup when waiting mutex

Author: zmshahaha

Diff for: examples/utest/testcases/kernel/mutex_pi_tc.c

@@ -233,7 +233,7 @@ static void test_mutex_pi_recursive_prio_update(void)
     rt_thread_startup(t_hi_prio);
 
     rt_thread_mdelay(1500);
-    
+
     for (int i = 0; i < 4; i++)
     {
         uassert_true(RT_SCHED_PRIV(t[i]).current_priority == 3);
@@ -258,7 +258,7 @@ static void test_mutex_waiter_to_wakeup_entry(void *para)
 {
     rt_thread_mdelay(1000);
     rt_err_t err = rt_mutex_take(&m[3], RT_WAITING_FOREVER);
-    uassert_true(err == -RT_ETIMEOUT);
+    uassert_true(err == -RT_EAGAIN);
 }
 
 static void wakeup_func(void *para)
@@ -285,7 +285,7 @@ static void test_mutex_pi_wakeup_mutex_waiter(void)
     rt_timer_init(&wakeup_timer, "wakeup_timer", wakeup_func, RT_NULL, rt_tick_from_millisecond(2000), RT_TIMER_FLAG_ONE_SHOT);
     rt_timer_start(&wakeup_timer);
     rt_thread_mdelay(1500);
-    
+
     for (int i = 0; i < 4; i++)
     {
         uassert_true(RT_SCHED_PRIV(t[i]).current_priority == 3);
@@ -304,6 +304,7 @@ static void test_mutex_pi_wakeup_mutex_waiter(void)
     {
         rt_mutex_detach(&m[i]);
     }
+    rt_timer_detach(&wakeup_timer);
 }
 
 static rt_err_t utest_tc_init(void)

Diff for: src/ipc.c

@@ -1448,13 +1448,13 @@ static rt_err_t _rt_mutex_take(rt_mutex_t mutex, rt_int32_t timeout, int suspend
 
                 rt_spin_lock(&(mutex->spinlock));
 
-                if (thread->error == RT_EOK)
+                if (mutex->owner == thread)
                 {
                     /**
                      * get mutex successfully
                      * Note: assert to avoid an unexpected resume
                      */
-                    RT_ASSERT(mutex->owner == thread);
+                    RT_ASSERT(thread->error == RT_EOK);
                 }
                 else
                 {
@@ -1466,6 +1466,11 @@ static rt_err_t _rt_mutex_take(rt_mutex_t mutex, rt_int32_t timeout, int suspend
                     /* get value first before calling to other APIs */
                     ret = thread->error;
 
+                    if (ret == RT_EOK)
+                    {
+                        ret = -RT_AGAIN;
+                    }
+
                     rt_sched_lock(&slvl);
 
                     /**