fix: revised TimerTaskManager and add some comments (OpenAtomFoundati…

…on#2776)

* 1 rename DisPatcherThread::timerTaskThread_ to timer_task_thread_
* 2 add comments for TimerTaskManager

---------

Co-authored-by: cheniujh <[email protected]>

src/net/src/dispatch_thread.cc

@@ -64,10 +64,10 @@ int DispatchThread::StartThread() {
   }
 
   // Adding timer tasks and run timertaskThread
-  timerTaskThread_.AddTimerTask("blrpop_blocking_info_scan", 250, true,
+  timer_task_thread_.AddTimerTask("blrpop_blocking_info_scan", 250, true,
                                 [this] { this->ScanExpiredBlockedConnsOfBlrpop(); });
-  timerTaskThread_.set_thread_name("TimerTaskThread");
-  timerTaskThread_.StartThread();
+  timer_task_thread_.set_thread_name("TimerTaskThread");
+  timer_task_thread_.StartThread();
   return ServerThread::StartThread();
 }
 
@@ -88,7 +88,7 @@ int DispatchThread::StopThread() {
       worker_thread_[i]->private_data_ = nullptr;
     }
   }
-  timerTaskThread_.StopThread();
+  timer_task_thread_.StopThread();
   return ServerThread::StopThread();
 }
 

src/net/src/dispatch_thread.h

@@ -161,7 +161,7 @@ class DispatchThread : public ServerThread {
    */
   std::shared_mutex block_mtx_;
 
-  TimerTaskThread timerTaskThread_;
+  TimerTaskThread timer_task_thread_;
 };  // class DispatchThread
 
 }  // namespace net

src/net/src/net_util.h

@@ -47,6 +47,12 @@ struct ExecTsWithId {
   }
 };
 
+/*
+ * For simplicity, current version of TimerTaskThread has no lock inside and all task should be registered before TimerTaskThread started,
+ * but if you have the needs of dynamically add/remove timer task after TimerTaskThread started, you can simply add a mutex to protect
+ * the timer_task_manager_ and also a pipe to wake up the maybe being endless-wait epoll(if all task consumed, epoll will sink into
+ * endless wait) to implement the feature.
+ */
 class TimerTaskManager {
  public:
   TimerTaskManager() = default;