change method of running thread count

sql/event_scheduler.cc

@@ -170,7 +170,6 @@ bool post_init_event_thread(THD *thd) {
 
   Global_THD_manager *thd_manager = Global_THD_manager::get_instance();
   thd_manager->add_thd(thd);
-  thd_manager->inc_thread_running();
   return false;
 }
 
@@ -190,7 +189,6 @@ void deinit_event_thread(THD *thd) {
   DBUG_PRINT("exit", ("Event thread finishing"));
   thd->release_resources();
   thd_manager->remove_thd(thd);
-  thd_manager->dec_thread_running();
   delete thd;
 }
 

sql/mysqld_thd_manager.cc

@@ -133,7 +133,6 @@ Global_THD_manager::Global_THD_manager()
       THD_array(PSI_INSTRUMENT_ME),
     },
     thread_ids(PSI_INSTRUMENT_ME),
-    atomic_num_thread_running(0),
     atomic_thread_created(0),
     thread_id_counter(reserved_thread_id + 1),
     unit_test(false)
@@ -315,6 +314,26 @@ THD *Global_THD_manager::find_thd(Find_thd_with_id *func) {
   return nullptr;
 }
 
+class Running_thread_count : public Do_THD_Impl {
+ public:
+  Running_thread_count() : m_count(0) {}
+  virtual void operator()(THD *thd) {
+    if (thd->get_command() != COM_SLEEP) {
+      m_count++;
+    }
+  }
+  int get_count() { return m_count; }
+
+ private:
+  int m_count;
+};
+
+int Global_THD_manager::get_num_thread_running() {
+  Running_thread_count thread_running;
+  Global_THD_manager::get_instance()->do_for_all_thd(&thread_running);
+  return thread_running.get_count();
+}
+
 void inc_thread_created() {
   Global_THD_manager::get_instance()->inc_thread_created();
 }

sql/mysqld_thd_manager.h

@@ -151,17 +151,7 @@ class Global_THD_manager {
     Retrieves thread running statistic variable.
     @return int Returns the total number of threads currently running
   */
-  int get_num_thread_running() const { return atomic_num_thread_running; }
-
-  /**
-    Increments thread running statistic variable.
-  */
-  void inc_thread_running() { atomic_num_thread_running++; }
-
-  /**
-    Decrements thread running statistic variable.
-  */
-  void dec_thread_running() { atomic_num_thread_running--; }
+  int get_num_thread_running();
 
   /**
     Retrieves thread created statistic variable.
@@ -267,9 +257,6 @@ class Global_THD_manager {
   // Mutex protecting thread_ids
   mysql_mutex_t LOCK_thread_ids;
 
-  // Count of active threads which are running queries in the system.
-  std::atomic<int> atomic_num_thread_running;
-
   // Cumulative number of threads created by mysqld daemon.
   std::atomic<ulonglong> atomic_thread_created;
 

sql/sql_parse.cc

@@ -1547,7 +1547,6 @@ bool dispatch_command(THD *thd, const COM_DATA *com_data,
   }
   thd->set_query_id(next_query_id());
   thd->reset_rewritten_query();
-  thd_manager->inc_thread_running();
 
   if (!(server_command_flags[command] & CF_SKIP_QUESTIONS))
     thd->status_var.questions++;
@@ -2195,8 +2194,6 @@ bool dispatch_command(THD *thd, const COM_DATA *com_data,
   /* Prevent rewritten query from getting "stuck" in SHOW PROCESSLIST. */
   thd->reset_rewritten_query();
 
-  thd_manager->dec_thread_running();
-
   /* Freeing the memroot will leave the THD::work_part_info invalid. */
   thd->work_part_info = nullptr;
 

unittest/gunit/thd_manager-t.cc

@@ -82,14 +82,6 @@ TEST_F(ThreadManagerTest, AddRemoveTHDWithGuard) {
   EXPECT_EQ(0U, thd_manager->get_thd_count());
 }
 
-TEST_F(ThreadManagerTest, IncDecThreadRunning) {
-  EXPECT_EQ(0, thd_manager->get_num_thread_running());
-  thd_manager->inc_thread_running();
-  EXPECT_EQ(1, thd_manager->get_num_thread_running());
-  thd_manager->dec_thread_running();
-  EXPECT_EQ(0, thd_manager->get_num_thread_running());
-}
-
 TEST_F(ThreadManagerTest, IncThreadCreated) {
   EXPECT_EQ(0U, thd_manager->get_num_thread_created());
   thd_manager->inc_thread_created();