[systemd-devel] [PATCH] Propagate reload from RELOADING=1 notifications

[Jouke Witteveen]

On Thu, Jan 1, 2015 at 7:15 PM, Zbigniew Jędrzejewski-Szmek
<zbyszek at in.waw.pl> wrote:
> On Tue, Dec 30, 2014 at 08:22:27PM +0100, Jouke Witteveen wrote:
>> ---
>>
>> This fixes #87251
>
> This is actually important information that should be included in the
> commit message (i.e. above not below "---"). We usually include the
> full url, since we also use distribution bug trackers and having the full
> url makes things easier to click. In this case:
>
> https://bugs.freedesktop.org/show_bug.cgi?id=87251

Will do. For consistency it is also better to not abort propagation if
one unit fails to reload, so I have a second version ready already.

>>  static void service_enter_reload_by_notify(Service *s) {
>> +        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
>> +        int r;
>> +
>>          assert(s);
>>
>>          if (s->timeout_start_usec > 0)
>>                  service_arm_timer(s, s->timeout_start_usec);
>>
>> +        r = manager_propagate_reload(UNIT(s)->manager, UNIT(s), JOB_REPLACE, false, &error);
>> +        if(r < 0)
>> +                log_unit_warning(UNIT(s)->id, "%s failed to schedule propagation of reload: %s", UNIT(s)->id, bus_error_message(&error, -r));
>> +
>
> Let's say that a.service has PropagateReloadsTo=b.service, and a.service provides
> the RELOADING=1 notification during a reload.
> What happens if a reload is requested with 'systemctl reload a', and systemd
> schedules a reload of a and b. Is it possible for b to be reloaded a second time
> as a result of notification of a? This should not happen, have you verified that
> this will not happen?

Isn't that just bad behavior? Sending a RELOADING=1 notification after
a reload is initiated? I guess if both service_enter_reload() and
service_enter_reload_by_notify() are called it is justified to
propagate two reloads. Before testing it might be nice to know what we
want :-).

Regards,
- Jouke