I tried this method.
http://dev.mysql.com/doc/refman/5.7/en/upgrading.html#upgrade-methods
Supported Upgrade Methods
Supported upgrade methods include:
In-place Upgrade: Involves shutting down the old MySQL version, replacing the old MySQL binaries or packages with the new ones, restarting MySQL on the existing data directory, and running mysql_upgrade.
Unfortunately binlog of 5.6 did not survive.
#mysql_upgrade
Checking if update is needed.
Checking server version.
...list of all tables - ok...
Upgrade process completed successfully.
Checking if update is needed.
Running queries to upgrade MySQL server.
select * from mysql.plugin;
| archive | ha_archive.so |
| blackhole | ha_blackhole.so |
| federated | ha_federated.so |
| innodb | ha_innodb.so |