[systemd-devel] systemd-218 - Requisite implies TriggeredByRestartOf

[Evert]

On 15-05-15 07:05, Andrei Borzenkov wrote:
> В Thu, 14 May 2015 21:23:38 +0200
> Evert пишет:
>
>> Hi,
>>
>> According to the systemd documentation, Requisite disallows starting a
>> unit unless the specified unit has been started. This seems to work
>> fine, however, if the specified unit has been restarted, this unit will
>> be started too!
>> This is not what should happen and it doesn't happen with a stop and
>> start of the specified unit, so clearly, restart behaves different than
>> stop followed by start.
>>
>> This can easily be reproduced using 2 dummy service units:
>>
>>
>> # dummy-1.service:
>> [Unit]
>> Description=dummy one
>> DefaultDependencies=false
>> After=local-fs.target
>> Before=basic.target
>>
>> [Service]
>> Type=oneshot
>> RemainAfterExit=yes
>> ExecStart=/bin/true
>> ExecReload=/bin/true
>> ExecStop=/bin/true
>>
>> [Install]
>> WantedBy=sysinit.target multi-user.target
>> Also=dummy-2.service
>>
>>
>> # dummy-2.service
>> [Unit]
>> Description=dummy TWO
>> DefaultDependencies=no
>> After=dummy-1.service
>> Before=shutdown.target
>> Requisite=dummy-1.service
>>
>> [Service]
>> Type=oneshot
>> RemainAfterExit=no
>> ExecStart=/bin/true
>>
>> [Install]
>> WantedBy=shutdown.target
>>
>>
>> # systemctl daemon-reload
>> # systemctl enable dummy-1
>> Created symlink from
>> /etc/systemd/system/sysinit.target.wants/dummy-1.service to
>> /etc/systemd/system/dummy-1.service.
>> Created symlink from
>> /etc/systemd/system/multi-user.target.wants/dummy-1.service to
>> /etc/systemd/system/dummy-1.service.
>> Created symlink from
>> /etc/systemd/system/shutdown.target.wants/dummy-2.service to
>> /etc/systemd/system/dummy-2.service.
>>
>> In another window I follow the journal which output I pasted after the
>> commands I execute:
>> # journalctl -f |grep dummy
>>
>> # systemctl start dummy-1
>> mei 14 19:58:20 joker systemd[1]: Started dummy one.
>>
>> # systemctl stop dummy-1
>> mei 14 19:58:25 joker systemd[1]: Stopping dummy one...
>> mei 14 19:58:25 joker systemd[1]: Stopped dummy one.
>>
>> # systemctl start dummy-1
>> mei 14 19:58:30 joker systemd[1]: Starting dummy one...
>> mei 14 19:58:30 joker systemd[1]: Started dummy one.
>>
>> # systemctl restart dummy-1
>> mei 14 19:58:34 joker systemd[1]: Stopping dummy one...
>> mei 14 19:58:34 joker systemd[1]: Starting dummy one...
>> mei 14 19:58:34 joker systemd[1]: Started dummy one.
>> mei 14 19:58:34 joker systemd[1]: Starting dummy TWO...
>> mei 14 19:58:34 joker systemd[1]: Started dummy TWO.
>>
>> # systemctl stop dummy-1
>> mei 14 19:58:39 joker systemd[1]: Stopping dummy one...
>> mei 14 19:58:39 joker systemd[1]: Stopped dummy one.
>>
>> # systemctl restart dummy-1
>> mei 14 19:58:43 joker systemd[1]: Starting dummy one...
>> mei 14 19:58:43 joker systemd[1]: Started dummy one.
>> mei 14 19:58:43 joker systemd[1]: Starting dummy TWO...
>> mei 14 19:58:43 joker systemd[1]: Started dummy TWO.
>>
>> As you can see, dummy-2 is not triggered by start or stop of dummy-1.
>> However, it *is* triggered by restart of dummy-1 (no matter if dummy-1
>> has been started or not). Am I missing something here or did I find a bug?
>>
>> IMHO restart should be no different than "stop ; start" and it should
>> certainly not trigger a unit which has a Requisite on that unit.
>
> I do not see it on openSUSE 13.2 with (heavily patched) systemd-210 so
> it appears to be a regression, unless there is some distro-specific
> patch.
>
> Reverse dependency for Requisite is Required-By and I have feeling it
> had already been discussed.
Distro is Gentoo Linux Stable with kernel 3.18.13 and
sys-apps/systemd-218-r3. The only systemd patch I see in the ebuild is
218-Dont-enable-audit-by-default.patch (journal/journald-audit.c) which
doesn't seem too exciting.

What is your message when you say "Reverse dependency for Requisite is
Required-By and I have feeling it
had already been discussed."?

What should I do now? Should I try systemd-219-r2, file a bug or simply
wait until it's fixed?

Evert