仔细检查后，发现是因为performance_schema数据库目录下 有其他非 数据库文件，因此mysql_upgrade删除时报错，手动删除performance_schema目录下的非数据库文件后，再次执行升级，这一步过了，但是又发生了报错：
mysql.columns_priv OK
mysql.db OK
mysql.event OK
mysql.func OK
mysql.general_log OK
mysql.help_category OK
mysql.help_keyword OK
mysql.help_relation OK
mysql.help_topic OK
mysql.host OK
mysql.innodb_index_stats OK
mysql.innodb_table_stats OK
mysql.ndb_binlog_index OK
mysql.plugin OK
mysql.proc OK
mysql.procs_priv OK
mysql.proxies_priv OK
mysql.servers OK
mysql.slave_master_info OK
mysql.slave_relay_log_info OK
mysql.slave_worker_info OK
mysql.slow_log OK
mysql.tables_priv OK
mysql.time_zone OK
mysql.time_zone_leap_second OK
mysql.time_zone_name OK
mysql.time_zone_transition OK
mysql.time_zone_transition_type OK
mysql.user OK
Running 'mysql_fix_privilege_tables'...
Running 'mysqlcheck' with connection arguments: '--socket=/data/mysql3307/data/mysqld3307.sock'
mysqlcheck: Got error: 1045: Access denied for user 'root'@'localhost' (using password: NO) when trying to connect
FATAL ERROR: Error during call to mysql_check for fixing the db/tables names on all db(s) except mysql