[kernel] improve comments

1 files changed, 7 insertions, 6 deletions

diff --git a/src/ipc.c b/src/ipc.c
index 09cc74e103..aea149a67a 100755
--- a/src/ipc.c
+++ b/src/ipc.c
@@ -725,8 +725,7 @@ RTM_EXPORT(rt_sem_control);
  *
  * @param    flag is the mutex flag, which determines the queuing way of how multiple threads wait
  *           when the mutex is not available.
- *           NOTE: The mutex flag can ONLY be RT_IPC_FLAG_PRIO. Using RT_IPC_FLAG_FIFO will seriously affect
- *           the real-time performance of the system.
+ *           NOTE: This parameter has been obsoleted. It can be RT_IPC_FLAG_PRIO, RT_IPC_FLAG_FIFO or RT_NULL.
  *
  * @return   Return the operation status. When the return value is RT_EOK, the initialization is successful.
  *           If the return value is any other values, it represents the initialization failed.
@@ -735,7 +734,8 @@ RTM_EXPORT(rt_sem_control);
  */
 rt_err_t rt_mutex_init(rt_mutex_t mutex, const char *name, rt_uint8_t flag)
 {
-    (void)flag;
+    /* flag parameter has been obsoleted */
+    RT_UNUSED(flag);
 
     /* parameter check */
     RT_ASSERT(mutex != RT_NULL);
@@ -807,8 +807,7 @@ RTM_EXPORT(rt_mutex_detach);
  *
  * @param    flag is the mutex flag, which determines the queuing way of how multiple threads wait
  *           when the mutex is not available.
- *           NOTE: The mutex flag can ONLY be RT_IPC_FLAG_PRIO. Using RT_IPC_FLAG_FIFO will seriously affect
- *           the real-time performance of the system.
+ *           NOTE: This parameter has been obsoleted. It can be RT_IPC_FLAG_PRIO, RT_IPC_FLAG_FIFO or RT_NULL.
  *
  * @return   Return a pointer to the mutex object. When the return value is RT_NULL, it means the creation failed.
  *
@@ -817,7 +816,9 @@ RTM_EXPORT(rt_mutex_detach);
 rt_mutex_t rt_mutex_create(const char *name, rt_uint8_t flag)
 {
     struct rt_mutex *mutex;
-    (void)flag;
+
+    /* flag parameter has been obsoleted */
+    RT_UNUSED(flag);
 
     RT_DEBUG_NOT_IN_INTERRUPT;