MDEV-13143 Server crashes in srv_init_abort_low() when started with inaccessible tmpdir

This is a regression caused by
commit bb60a832

srv_shutdown_all_bg_threads(): If os_thread_count indicates that
no threads are running, do not bother checking thread status.
This avoids a crash when InnoDB startup is aborted before
os_aio_init() has been invoked. (os_aio_all_slots_free() would
dereference AIO::s_reads even though it is NULL.)

mysql-test/suite/innodb/r/temporary_table.result

@@ -137,6 +137,8 @@ Tables_in_test
 create temporary table t1 (keyc int, c1 char(100), c2 char(100)) engine = innodb;
 ERROR HY000: Can't create table `test`.`t1` (errno: 165 "Table is read only")
 # test various bad start-up parameters
+FOUND 3 /Can't create/write to file '.dev.null.nonexistent.ib/ in mysqld.1.err
+FOUND 3 /InnoDB: Unable to create temporary file/ in mysqld.1.err
 FOUND 1 /innodb_temporary and innodb_system file names seem to be the same/ in mysqld.1.err
 SELECT * FROM INFORMATION_SCHEMA.ENGINES WHERE engine = 'innodb'
 AND support IN ('YES', 'DEFAULT', 'ENABLED');

mysql-test/suite/innodb/t/temporary_table.test

@@ -10,6 +10,8 @@
 --source include/no_valgrind_without_big.inc
 
 --disable_query_log
+call mtr.add_suppression("Can't create/write to file '.dev.null.nonexistent.ib");
+call mtr.add_suppression("InnoDB: Unable to create temporary file");
 call mtr.add_suppression("last file in setting innodb_temp_data_file_path");
 call mtr.add_suppression("The table 't1' is full");
 call mtr.add_suppression("Plugin 'InnoDB' init function returned error");
@@ -125,6 +127,35 @@ let SEARCH_ABORT = NOT FOUND;
 let $check_no_innodb=SELECT * FROM INFORMATION_SCHEMA.ENGINES WHERE engine = 'innodb'
 AND support IN ('YES', 'DEFAULT', 'ENABLED');
 
+# We cannot use include/restart_mysqld.inc in this particular test,
+# because SHOW STATUS would fail due to unwritable (nonexistent) tmpdir.
+--source include/shutdown_mysqld.inc
+--exec echo "restart: --tmpdir=/dev/null/nonexistent" > $_expect_file_name
+--enable_reconnect
+--disable_result_log
+--disable_query_log
+let $counter= 5000;
+let $mysql_errno= 9999;
+while ($mysql_errno)
+{
+  --error 0,ER_SERVER_SHUTDOWN,ER_CONNECTION_KILLED,2002,2006,2013
+  select 1;
+
+  dec $counter;
+  if (!$counter)
+  {
+    --die Server failed to restart
+  }
+  --sleep 0.1
+}
+--enable_query_log
+--enable_result_log
+--disable_reconnect
+--let SEARCH_PATTERN= Can't create/write to file '.dev.null.nonexistent.ib
+--source include/search_pattern_in_file.inc
+--let SEARCH_PATTERN= InnoDB: Unable to create temporary file
+--source include/search_pattern_in_file.inc
+
 --let $restart_parameters= --innodb_data_file_path=ibdata1:12M:autoextend --innodb_temp_data_file_path=ibdata1:12M:autoextend
 --source include/restart_mysqld.inc
 --let SEARCH_PATTERN = innodb_temporary and innodb_system file names seem to be the same

storage/innobase/srv/srv0start.cc

@@ -1302,6 +1302,10 @@ srv_shutdown_all_bg_threads()
 			}
 		}
 
+		if (!os_thread_count) {
+			return;
+		}
+
 		switch (srv_operation) {
 		case SRV_OPERATION_BACKUP:
 			break;
@@ -1313,10 +1317,6 @@ srv_shutdown_all_bg_threads()
 			}
 		}
 
-		if (!os_thread_count) {
-			return;
-		}
-
 		os_thread_sleep(100000);
 	}