feat: ipc: add nested-free flag support to mutex

include/rtdef.h

@@ -1028,7 +1028,7 @@ struct rt_mutex
     rt_uint8_t           ceiling_priority;              /**< the priority ceiling of mutexe */
     rt_uint8_t           priority;                      /**< the maximal priority for pending thread */
     rt_uint8_t           hold;                          /**< numbers of thread hold the mutex */
-    rt_uint8_t           reserved;                      /**< reserved field */
+    rt_uint8_t           ctrl_flags;                    /**< flags to control mutex behavior */
 
     struct rt_thread    *owner;                         /**< current owner of mutex */
     rt_list_t            taken_list;                    /**< the object list taken by thread */

include/rtthread.h

@@ -445,13 +445,18 @@ rt_err_t rt_sem_control(rt_sem_t sem, int cmd, void *arg);
  */
 
 #ifdef RT_USING_MUTEX
+
+#define RT_MTX_CTRL_FLAG_DEFAULT    0x0     /* create a mutex with default behavior */
+#define RT_MTX_CTRL_FLAG_RESERVED   0x01    /* RESERVED for legacy IPC flag */
+RT_STATIC_ASSERT(ident_to_ipc_flag, RT_MTX_CTRL_FLAG_RESERVED == RT_IPC_FLAG_PRIO);
+#define RT_MTX_CTRL_FLAG_NO_RECUR   0x02    /* create a mutex without recursive taken */
 /*
  * mutex interface
  */
-rt_err_t rt_mutex_init(rt_mutex_t mutex, const char *name, rt_uint8_t flag);
+rt_err_t rt_mutex_init(rt_mutex_t mutex, const char *name, rt_uint8_t ctrl_flag);
 rt_err_t rt_mutex_detach(rt_mutex_t mutex);
 #ifdef RT_USING_HEAP
-rt_mutex_t rt_mutex_create(const char *name, rt_uint8_t flag);
+rt_mutex_t rt_mutex_create(const char *name, rt_uint8_t ctrl_flag);
 rt_err_t rt_mutex_delete(rt_mutex_t mutex);
 #endif /* RT_USING_HEAP */
 void rt_mutex_drop_thread(rt_mutex_t mutex, rt_thread_t thread);

src/ipc.c

@@ -980,6 +980,23 @@ static void _mutex_before_delete_detach(rt_mutex_t mutex)
  * @{
  */
 
+static void _mutex_init(rt_mutex_t mutex, rt_uint8_t ctrl_flags)
+{
+    /* initialize ipc object */
+    _ipc_object_init(&(mutex->parent));
+
+    mutex->owner    = RT_NULL;
+    mutex->priority = 0xFF;
+    mutex->hold     = 0;
+    mutex->ceiling_priority = 0xFF;
+    mutex->ctrl_flags = ctrl_flags;
+    rt_list_init(&(mutex->taken_list));
+
+    /* flag can only be RT_IPC_FLAG_PRIO. RT_IPC_FLAG_FIFO cannot solve the unbounded priority inversion problem */
+    mutex->parent.parent.flag = RT_IPC_FLAG_PRIO;
+    rt_spin_lock_init(&(mutex->spinlock));
+}
+
 /**
  * @brief    Initialize a static mutex object.
  *
@@ -1004,29 +1021,15 @@ static void _mutex_before_delete_detach(rt_mutex_t mutex)
  *
  * @warning  This function can ONLY be called from threads.
  */
-rt_err_t rt_mutex_init(rt_mutex_t mutex, const char *name, rt_uint8_t flag)
+rt_err_t rt_mutex_init(rt_mutex_t mutex, const char *name, rt_uint8_t ctrl_flag)
 {
-    /* flag parameter has been obsoleted */
-    RT_UNUSED(flag);
-
     /* parameter check */
     RT_ASSERT(mutex != RT_NULL);
 
     /* initialize object */
     rt_object_init(&(mutex->parent.parent), RT_Object_Class_Mutex, name);
 
-    /* initialize ipc object */
-    _ipc_object_init(&(mutex->parent));
-
-    mutex->owner    = RT_NULL;
-    mutex->priority = 0xFF;
-    mutex->hold     = 0;
-    mutex->ceiling_priority = 0xFF;
-    rt_list_init(&(mutex->taken_list));
-
-    /* flag can only be RT_IPC_FLAG_PRIO. RT_IPC_FLAG_FIFO cannot solve the unbounded priority inversion problem */
-    mutex->parent.parent.flag = RT_IPC_FLAG_PRIO;
-    rt_spin_lock_init(&(mutex->spinlock));
+    _mutex_init(mutex, ctrl_flag);
 
     return RT_EOK;
 }
@@ -1230,32 +1233,18 @@ RTM_EXPORT(rt_mutex_getprioceiling);
  *
  * @warning  This function can ONLY be called from threads.
  */
-rt_mutex_t rt_mutex_create(const char *name, rt_uint8_t flag)
+rt_mutex_t rt_mutex_create(const char *name, rt_uint8_t ctrl_flags)
 {
     struct rt_mutex *mutex;
 
-    /* flag parameter has been obsoleted */
-    RT_UNUSED(flag);
-
     RT_DEBUG_NOT_IN_INTERRUPT;
 
     /* allocate object */
     mutex = (rt_mutex_t)rt_object_allocate(RT_Object_Class_Mutex, name);
     if (mutex == RT_NULL)
         return mutex;
 
-    /* initialize ipc object */
-    _ipc_object_init(&(mutex->parent));
-
-    mutex->owner    = RT_NULL;
-    mutex->priority = 0xFF;
-    mutex->hold     = 0;
-    mutex->ceiling_priority = 0xFF;
-    rt_list_init(&(mutex->taken_list));
-
-    /* flag can only be RT_IPC_FLAG_PRIO. RT_IPC_FLAG_FIFO cannot solve the unbounded priority inversion problem */
-    mutex->parent.parent.flag = RT_IPC_FLAG_PRIO;
-    rt_spin_lock_init(&(mutex->spinlock));
+    _mutex_init(mutex, ctrl_flags);
 
     return mutex;
 }
@@ -1351,7 +1340,8 @@ static rt_err_t _rt_mutex_take(rt_mutex_t mutex, rt_int32_t timeout, int suspend
 
     if (mutex->owner == thread)
     {
-        if (mutex->hold < RT_MUTEX_HOLD_MAX)
+        if (!(mutex->ctrl_flags & RT_MTX_CTRL_FLAG_NO_RECUR) &&
+            mutex->hold < RT_MUTEX_HOLD_MAX)
         {
             /* it's the same thread */
             mutex->hold ++;