Fix threadpool to report connections aborted due to wait timeout.

Update wait_timeout.test to add test case for this.

mysql-test/r/wait_timeout.result

@@ -35,3 +35,9 @@ SELECT 3;
 SET @@global.wait_timeout= <start_value>;
 disconnect con1;
 connect  default,localhost,root,,test,,;
+set global log_warnings=2;
+connect  foo,localhost,root;
+set @@wait_timeout=1;
+connection default;
+FOUND 1 /Aborted.*Got timeout reading communication packets/ in mysqld.1.err
+set global log_warnings=@@log_warnings;

mysql-test/r/wait_timeout_not_windows.result

-set global log_warnings=2;
-connect  foo,localhost,root;
-set @@wait_timeout=1;
-connection default;
-FOUND 1 /Aborted.*Got timeout reading communication packets/ in mysqld.1.err
-set global log_warnings=@@log_warnings;

mysql-test/t/wait_timeout.test

@@ -122,10 +122,22 @@ SELECT 3;
 eval SET @@global.wait_timeout= $start_value;
 disconnect con1;
 
-
-# The last connect is to keep tools checking the current test happy.
 connect (default,localhost,root,,test,,);
 
+#
+# MDEV-7775 Wrong error message (Unknown error) when idle sessions are killed after wait_timeout
+#
+set global log_warnings=2;
+connect (foo,localhost,root);
+set @@wait_timeout=1;
+sleep 2;
+connection default;
+let SEARCH_FILE=$MYSQLTEST_VARDIR/log/mysqld.1.err;
+let SEARCH_PATTERN= Aborted.*Got timeout reading communication packets;
+source include/search_pattern_in_file.inc;
+set global log_warnings=@@log_warnings;
+
+
 # Wait till all disconnects are completed
 --source include/wait_until_count_sessions.inc
 

mysql-test/t/wait_timeout_not_windows.test

-source include/not_embedded.inc;
-source include/not_windows.inc;
-
-#
-# MDEV-7775 Wrong error message (Unknown error) when idle sessions are killed after wait_timeout
-#
-set global log_warnings=2;
-connect (foo,localhost,root);
-set @@wait_timeout=1;
-sleep 2;
-connection default;
-let SEARCH_FILE=$MYSQLTEST_VARDIR/log/mysqld.1.err;
-let SEARCH_PATTERN= Aborted.*Got timeout reading communication packets;
-source include/search_pattern_in_file.inc;
-set global log_warnings=@@log_warnings;

sql/signal_handler.cc

@@ -204,6 +204,10 @@ extern "C" sig_handler handle_fatal_signal(int sig)
     case KILL_SLAVE_SAME_ID:
       kreason= "KILL_SLAVE_SAME_ID";
       break;
+    case KILL_WAIT_TIMEOUT:
+    case KILL_WAIT_TIMEOUT_HARD:
+      kreason= "KILL_WAIT_TIMEOUT";
+      break;
     }
     my_safe_printf_stderr("%s", "\n"
       "Trying to get some variables.\n"

sql/sql_class.cc

@@ -2008,6 +2008,9 @@ int THD::killed_errno()
     DBUG_RETURN(ER_SERVER_SHUTDOWN);
   case KILL_SLAVE_SAME_ID:
     DBUG_RETURN(ER_SLAVE_SAME_ID);
+  case KILL_WAIT_TIMEOUT:
+  case KILL_WAIT_TIMEOUT_HARD:
+    DBUG_RETURN(ER_NET_READ_INTERRUPTED);
   }
   DBUG_RETURN(0);                               // Keep compiler happy
 }

sql/sql_class.h

@@ -492,6 +492,11 @@ enum killed_state
   KILL_SYSTEM_THREAD_HARD= 15,
   KILL_SERVER= 16,
   KILL_SERVER_HARD= 17,
+  /*
+    Used in threadpool to signal wait timeout.
+  */
+  KILL_WAIT_TIMEOUT= 18,
+  KILL_WAIT_TIMEOUT_HARD= 19
 
 };
 

sql/threadpool_common.cc

@@ -308,6 +308,24 @@ static void threadpool_remove_connection(THD *thd)
   my_thread_end();
 }
 
+
+/*
+  Ensure that proper error message is sent to client,
+  and "aborted" message appears in the log in case of
+  wait timeout.
+
+  See also timeout handling in net_serv.cc
+*/
+static void handle_wait_timeout(THD *thd)
+{
+  thd->get_stmt_da()->reset_diagnostics_area();
+  thd->reset_killed();
+  my_error(ER_NET_READ_INTERRUPTED, MYF(0));
+  thd->net.last_errno= ER_NET_READ_INTERRUPTED;
+  thd->net.error= 2;
+}
+
+
 /**
  Process a single client request or a single batch.
 */
@@ -323,6 +341,8 @@ static int threadpool_process_request(THD *thd)
       or KILL command. Return error.
     */
     retval= 1;
+    if(thd->killed == KILL_WAIT_TIMEOUT)
+      handle_wait_timeout(thd);
     goto end;
   }
 
@@ -458,7 +478,7 @@ void tp_timeout_handler(TP_connection *c)
     return;
   THD *thd=c->thd;
   mysql_mutex_lock(&thd->LOCK_thd_data);
-  thd->killed= KILL_CONNECTION;
+  thd->set_killed(KILL_WAIT_TIMEOUT);
   c->priority= TP_PRIORITY_HIGH;
   post_kill_notification(thd);
   mysql_mutex_unlock(&thd->LOCK_thd_data);