import

Kernel/SingleCore/os_mutex.c

@@ -0,0 +1,104 @@
+#include <os_mutex.h>
+#include "os_critical.h"
+
+
+void os_mutex_init(os_mutex_t* self){
+    self->owner = 0;
+    os_waitobject_init(&self->wait_obj);
+}
+
+void os_mutex_destroy(os_mutex_t* self){
+    OS_ASSERT(self->owner==0);
+}
+
+os_err_t os_mutex_trylock(os_mutex_t* self){
+    os_critical_enter();
+    os_task_t* p_thread =  os_task_self();
+
+    if(self->owner!=0){ // 已经被锁定了
+        if(self->owner==p_thread){ // 是当前任务锁定的
+            os_critical_leave();
+            return OS_ERR_OK;
+        }
+
+        // 当前任务不是 owner，判断优先级是否反转
+        if(os_priority_cmp(p_thread->curr_priority, self->owner->curr_priority)==OS_PRIORITY_CMP_HIGH){
+            // 当前任务的优先级更高，优先级反转了，提升 owner 优先级
+            self->owner->curr_priority = p_thread->curr_priority;
+        }
+
+        os_critical_leave();
+        return OS_ERR_FAIL;
+    }
+
+    // 到这里说明没有owner
+    self->owner = (os_task_t*)p_thread;
+    os_critical_leave();
+    return OS_ERR_OK;
+}
+
+os_err_t os_mutex_lock(os_mutex_t* self){
+
+    while(os_mutex_trylock(self)!=OS_ERR_OK){
+        os_task_yield();        // 未获得锁，主动让出
+    }
+
+    return OS_ERR_OK;
+}
+
+os_err_t os_mutex_timed_lock(os_mutex_t* self, os_tick_t ticks){
+    if(os_mutex_trylock(self)!=OS_ERR_OK){
+        os_critical_enter();
+        os_task_t* p_task = os_task_self();
+        os_critical_leave();
+        return os_waitobject_timed_wait(&self->wait_obj, p_task, ticks);
+    }
+    return OS_ERR_OK;
+}
+
+void os_mutex_unlock(os_mutex_t* self){
+    os_critical_enter();
+
+    os_task_t* p_task = os_task_self();
+
+    if(self->owner != p_task){
+        // 只有 owner 才能 unlock
+        os_critical_leave();
+        os_task_yield();
+        return;
+    }
+
+    if(self->owner->curr_priority!=self->owner->init_priority) {
+        self->owner->curr_priority = self->owner->init_priority; /* 恢复优先级 */
+    }
+    self->owner = 0;
+
+    os_critical_leave();
+
+    os_waitobject_notify_all(&self->wait_obj);
+}
+
+void os_mutex_unlock_one(os_mutex_t* self){
+    os_critical_enter();
+
+    os_task_t* p_task = os_task_self();
+
+    if(self->owner != p_task){
+        // 只有 owner 才能 unlock
+        os_critical_leave();
+        os_task_yield();
+        return;
+    }
+
+    if(self->owner->curr_priority!=self->owner->init_priority) {
+        self->owner->curr_priority = self->owner->init_priority; /* 恢复优先级 */
+    }
+    self->owner = 0;
+
+    // 将所有等待任务加入就绪表，等待当前任务用时完成后进行调度
+
+    os_critical_leave();
+
+    os_waitobject_notify_one(&self->wait_obj);
+}
+