diff --git a/sql/mysqld.cc b/sql/mysqld.cc
index d4b49047046..f5a53597325 100644
--- a/sql/mysqld.cc
+++ b/sql/mysqld.cc
@@ -1523,27 +1523,7 @@ static void kill_thread(THD *thd)
 {
   if (WSREP(thd)) mysql_mutex_lock(&thd->LOCK_thd_data);
   mysql_mutex_lock(&thd->LOCK_thd_kill);
-  if (thd->mysys_var)
-  {
-    thd->mysys_var->abort= 1;
-    mysql_mutex_lock(&thd->mysys_var->mutex);
-    if (thd->mysys_var->current_cond)
-    {
-      for (uint i= 0; i < 2; i++)
-      {
-        int ret= mysql_mutex_trylock(thd->mysys_var->current_mutex);
-        mysql_cond_broadcast(thd->mysys_var->current_cond);
-        if (!ret)
-        {
-          /* Thread has surely got the signal, unlock and abort */
-          mysql_mutex_unlock(thd->mysys_var->current_mutex);
-          break;
-        }
-        sleep(1);
-      }
-    }
-    mysql_mutex_unlock(&thd->mysys_var->mutex);
-  }
+  thd->abort_current_cond_wait(true);
   mysql_mutex_unlock(&thd->LOCK_thd_kill);
   if (WSREP(thd)) mysql_mutex_unlock(&thd->LOCK_thd_data);
 }
diff --git a/sql/sql_class.cc b/sql/sql_class.cc
index 5c1ad49c9de..d815dd56647 100644
--- a/sql/sql_class.cc
+++ b/sql/sql_class.cc
@@ -49,9 +49,6 @@
 #include <m_ctype.h>
 #include <sys/stat.h>
 #include <thr_alarm.h>
-#ifdef	__WIN__0
-#include <io.h>
-#endif
 #include <mysys_err.h>
 #include <limits.h>
 
@@ -70,6 +67,8 @@
 #ifdef WITH_WSREP
 #include "wsrep_thd.h"
 #include "wsrep_trans_observer.h"
+#else
+static inline bool wsrep_is_bf_aborted(THD* thd) { return false; }
 #endif /* WITH_WSREP */
 #include "opt_trace.h"
 
@@ -1902,15 +1901,21 @@ void THD::awake_no_mutex(killed_state state_to_set)
   }
 
   /* Interrupt target waiting inside a storage engine. */
-  if (IF_WSREP(state_to_set != NOT_KILLED  && !wsrep_is_bf_aborted(this),
-               state_to_set != NOT_KILLED))
+  if (state_to_set != NOT_KILLED  && !wsrep_is_bf_aborted(this))
     ha_kill_query(this, thd_kill_level(this));
 
-  /* Broadcast a condition to kick the target if it is waiting on it. */
+  abort_current_cond_wait(false);
+  DBUG_VOID_RETURN;
+}
+
+/* Broadcast a condition to kick the target if it is waiting on it. */
+void THD::abort_current_cond_wait(bool force)
+{
+  mysql_mutex_assert_owner(&LOCK_thd_kill);
   if (mysys_var)
   {
     mysql_mutex_lock(&mysys_var->mutex);
-    if (!system_thread)		// Don't abort locks
+    if (!system_thread || force)                 // Don't abort locks
       mysys_var->abort=1;
 
     /*
@@ -1968,7 +1973,6 @@ void THD::awake_no_mutex(killed_state state_to_set)
     }
     mysql_mutex_unlock(&mysys_var->mutex);
   }
-  DBUG_VOID_RETURN;
 }
 
 
@@ -2022,16 +2026,7 @@ bool THD::notify_shared_lock(MDL_context_owner *ctx_in_use,
     mysql_mutex_lock(&in_use->LOCK_thd_kill);
     if (in_use->killed < KILL_CONNECTION)
       in_use->set_killed_no_mutex(KILL_CONNECTION);
-    if (in_use->mysys_var)
-    {
-      mysql_mutex_lock(&in_use->mysys_var->mutex);
-      if (in_use->mysys_var->current_cond)
-        mysql_cond_broadcast(in_use->mysys_var->current_cond);
-
-      /* Abort if about to wait in thr_upgrade_write_delay_lock */
-      in_use->mysys_var->abort= 1;
-      mysql_mutex_unlock(&in_use->mysys_var->mutex);
-    }
+    in_use->abort_current_cond_wait(true);
     mysql_mutex_unlock(&in_use->LOCK_thd_kill);
     signalled= TRUE;
   }
diff --git a/sql/sql_class.h b/sql/sql_class.h
index 77bde414b31..be61a4047ec 100644
--- a/sql/sql_class.h
+++ b/sql/sql_class.h
@@ -3322,6 +3322,7 @@ public:
     if (wsrep_on_local)
       mysql_mutex_unlock(&LOCK_thd_data);
   }
+  void abort_current_cond_wait(bool force);
  
   /** Disconnect the associated communication endpoint. */
   void disconnect();
@@ -4061,8 +4062,7 @@ public:
     mysql_mutex_lock(&LOCK_thd_kill);
     int err= killed_errno();
     if (err)
-      my_message(err, killed_err ? killed_err->msg : ER_THD(this, err),
-                 MYF(0));
+      my_message(err, killed_err ? killed_err->msg : ER_THD(this, err), MYF(0));
     mysql_mutex_unlock(&LOCK_thd_kill);
   }
   /* return TRUE if we will abort query if we make a warning now */
diff --git a/sql/sql_insert.cc b/sql/sql_insert.cc
index c728203f07a..a3211629180 100644
--- a/sql/sql_insert.cc
+++ b/sql/sql_insert.cc
@@ -2869,23 +2869,7 @@ void kill_delayed_threads(void)
     mysql_mutex_lock(&di->thd.LOCK_thd_kill);
     if (di->thd.killed < KILL_CONNECTION)
       di->thd.set_killed_no_mutex(KILL_CONNECTION);
-    if (di->thd.mysys_var)
-    {
-      mysql_mutex_lock(&di->thd.mysys_var->mutex);
-      if (di->thd.mysys_var->current_cond)
-      {
-	/*
-	  We need the following test because the main mutex may be locked
-	  in handle_delayed_insert()
-	*/
-	if (&di->mutex != di->thd.mysys_var->current_mutex)
-          mysql_mutex_lock(di->thd.mysys_var->current_mutex);
-        mysql_cond_broadcast(di->thd.mysys_var->current_cond);
-	if (&di->mutex != di->thd.mysys_var->current_mutex)
-          mysql_mutex_unlock(di->thd.mysys_var->current_mutex);
-      }
-      mysql_mutex_unlock(&di->thd.mysys_var->mutex);
-    }
+    di->thd.abort_current_cond_wait(false);
     mysql_mutex_unlock(&di->thd.LOCK_thd_kill);
   }
   mysql_mutex_unlock(&LOCK_delayed_insert); // For unlink from list
diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index de96f0c8924..7b90bac2a42 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -9079,10 +9079,9 @@ struct find_thread_callback_arg
 };
 
 
-my_bool find_thread_callback(THD *thd, find_thread_callback_arg *arg)
+static my_bool find_thread_callback(THD *thd, find_thread_callback_arg *arg)
 {
-  if (thd->get_command() != COM_DAEMON &&
-      arg->id == (arg->query_id ? thd->query_id : (longlong) thd->thread_id))
+  if (arg->id == (arg->query_id ? thd->query_id : (longlong) thd->thread_id))
   {
     mysql_mutex_lock(&thd->LOCK_thd_kill);    // Lock from delete
     arg->thd= thd;
@@ -9100,10 +9099,9 @@ THD *find_thread_by_id(longlong id, bool query_id)
 }
 
 #ifdef WITH_WSREP
-my_bool find_thread_with_thd_data_lock_callback(THD *thd, find_thread_callback_arg *arg)
+static my_bool find_thread_with_thd_data_lock_callback(THD *thd, find_thread_callback_arg *arg)
 {
-  if (thd->get_command() != COM_DAEMON &&
-      arg->id == (arg->query_id ? thd->query_id : (longlong) thd->thread_id))
+  if (arg->id == (arg->query_id ? thd->query_id : (longlong) thd->thread_id))
   {
     if (WSREP(thd)) mysql_mutex_lock(&thd->LOCK_thd_data);
     mysql_mutex_lock(&thd->LOCK_thd_kill);    // Lock from delete
@@ -9137,10 +9135,14 @@ kill_one_thread(THD *thd, longlong id, killed_state kill_signal, killed_type typ
   DBUG_ENTER("kill_one_thread");
   DBUG_PRINT("enter", ("id: %lld  signal: %u", id, (uint) kill_signal));
 #ifdef WITH_WSREP
-  if (id && (tmp= find_thread_by_id_with_thd_data_lock(id, type == KILL_TYPE_QUERY)))
+  tmp= find_thread_by_id_with_thd_data_lock(id, type == KILL_TYPE_QUERY);
 #else
-  if (id && (tmp= find_thread_by_id(id, type == KILL_TYPE_QUERY)))
+  tmp= find_thread_by_id(id, type == KILL_TYPE_QUERY);
 #endif
+  if (!tmp)
+    DBUG_RETURN(error);
+
+  if (tmp->get_command() != COM_DAEMON)
   {
     /*
       If we're SUPER, we can KILL anything, including system-threads.
@@ -9194,11 +9196,11 @@ kill_one_thread(THD *thd, longlong id, killed_state kill_signal, killed_type typ
     else
       error= (type == KILL_TYPE_QUERY ? ER_KILL_QUERY_DENIED_ERROR :
                                         ER_KILL_DENIED_ERROR);
-#ifdef WITH_WSREP
-    if (WSREP(tmp)) mysql_mutex_unlock(&tmp->LOCK_thd_data);
-#endif
-    mysql_mutex_unlock(&tmp->LOCK_thd_kill);
   }
+#ifdef WITH_WSREP
+  if (WSREP(tmp)) mysql_mutex_unlock(&tmp->LOCK_thd_data);
+#endif
+  mysql_mutex_unlock(&tmp->LOCK_thd_kill);
   DBUG_PRINT("exit", ("%d", error));
   DBUG_RETURN(error);
 }
diff --git a/sql/sql_show.cc b/sql/sql_show.cc
index ad2a489c39d..eac4af52ef4 100644
--- a/sql/sql_show.cc
+++ b/sql/sql_show.cc
@@ -3256,11 +3256,8 @@ int fill_show_explain(THD *thd, TABLE_LIST *table, COND *cond)
     }
     DBUG_RETURN(bres);
   }
-  else
-  {
-    my_error(ER_NO_SUCH_THREAD, MYF(0), (ulong) thread_id);
-    DBUG_RETURN(1);
-  }
+  my_error(ER_NO_SUCH_THREAD, MYF(0), (ulong) thread_id);
+  DBUG_RETURN(1);
 }
 
 
diff --git a/sql/wsrep_mysqld.cc b/sql/wsrep_mysqld.cc
index c0f48cca9cd..8e68f7229eb 100644
--- a/sql/wsrep_mysqld.cc
+++ b/sql/wsrep_mysqld.cc
@@ -2384,18 +2384,7 @@ static void wsrep_close_thread(THD *thd)
   thd->set_killed(KILL_CONNECTION);
   MYSQL_CALLBACK(thread_scheduler, post_kill_notification, (thd));
   mysql_mutex_lock(&thd->LOCK_thd_kill);
-  if (thd->mysys_var)
-  {
-    thd->mysys_var->abort=1;
-    mysql_mutex_lock(&thd->mysys_var->mutex);
-    if (thd->mysys_var->current_cond)
-    {
-      mysql_mutex_lock(thd->mysys_var->current_mutex);
-      mysql_cond_broadcast(thd->mysys_var->current_cond);
-      mysql_mutex_unlock(thd->mysys_var->current_mutex);
-    }
-    mysql_mutex_unlock(&thd->mysys_var->mutex);
-  }
+  thd->abort_current_cond_wait(true);
   mysql_mutex_unlock(&thd->LOCK_thd_kill);
 }