mariadb.inc: fix mysqld hung at first init time based on systemd

While SYSTEMD_AUTO_ENABLE_mariadb-server = "enable", the mysqld service
hungs.
...
[    **] A start job is running for Run pending postinsts (25s / no limit)
[  OK  ] Stopped MariaDB database server.
...

In mariadb-server's pkg_postinst, it install db at first runtime. And the
following 'systemctl mysqld restart' casued the hunging. So the fix idea
is to reomove pkg_postinst and still install db at first runtime.

Introduce mysql-systemd-start from ${S}/packaging/rpm-oel/. For review
convenience, we add them as file.

The mysql-systemd-start provides two functions: the install_db is to install
db at fist runtime (the first runtime means if a db existed, the install_db
will directly exit); the pinger is to wait for mysqld service startup
completed.

The mysqld.service add ExecStartPost than previous which invoke
'mysql-systemd-start post' to wait for mysqld service startup completed.

We add a package to provide install_db, so the user could choose it
to install database for mariadb at first boot before mysqld started.

It also fix another issue:
When you manually restart mysqld and do mysql test to connect the server,
the return of the restart could make sure mysqld is ready, and the following db
connect will not fail with:
...
Can't connect to local MySQL server through socket
...

Tweak my.cnf to remove obsolete/incorrect parameter.

Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/meta-oe/recipes-support/mysql/mariadb/mysqld.service b/meta-oe/recipes-support/mysql/mariadb/mysqld.service
index 757d0386c..d88361703 100644
--- a/meta-oe/recipes-support/mysql/mariadb/mysqld.service
+++ b/meta-oe/recipes-support/mysql/mariadb/mysqld.service
@@ -8,7 +8,16 @@ PIDFile=/var/lib/mysql/mysqld.pid
 Type=simple
 User=mysql
 Group=mysql
+
+# Execute post scripts as root
+PermissionsStartOnly=true
+
+# Start main service
 ExecStart=@BINDIR@/mysqld_safe --basedir=@PREFIX@
+
+# Don't signal startup success before a ping works
+ExecStartPost=@BINDIR@/mysql-systemd-start post
+
 TimeoutSec=300
 PrivateTmp=true