RFC: new design of phosphor-time-manager on sdbusplus

[Patrick Williams]

On Tue, Jan 17, 2017 at 03:51:39PM +0800, Mine wrote:
> On Tue, Jan 17, 2017 at 3:44 AM, Patrick Williams <patrick at stwcx.xyz> wrote:
> > On Fri, Jan 13, 2017 at 03:42:50PM +0800, Mine wrote:

> I should be meant to create two "instances" on the bus, eventually it looks
> something like:
> ```
> xyz.openbmc_project.Time.Manager
>     /xyz/openbmc_project/time/host_epoch
>         org.freedesktop.DBus.Peer
>         org.freedesktop.DBus.Introspectable
>         org.freedesktop.DBus.Properties
>         xyz.openbmc_project.Time.EpochTime
>     /xyz/openbmc_project/time/bmc_epoch
>         org.freedesktop.DBus.Peer
>         org.freedesktop.DBus.Introspectable
>         org.freedesktop.DBus.Properties
>         xyz.openbmc_project.Time.EpochTime

There isn't a reason to name the object path "epoch".  /time/bmc and
/time/host0 is probably more appropriate.

> > > And there will be no “curr_time_mode/owner” or “requested_time_mode/owner”
> > > properties on DBUS.
> >
> > So these are only stored in phosphor-settingsd now or are they also used
> > internally for decisions?  I believe the previous implementation had
> > them exposed more for debug purposes.  Are you going to add them to the
> > journal at least?
> 
> Yes, the time_mode and time_owner are still stored in
> phosphor-settingsd, and they
> are used internally by phosphor-time-manager, which will register
> callback for the
> settings' change and handled accordingly.
> The difference from the previous implementation is that we do not expose these
> settings in time-manager's DBus now.

There are two aspects for consideration here:

    1. The current time manager defers changing the host policies until
       the next boot.  We need to continue this behavior.

    2. If the process restarts we need it to go back into the "current
       state" and not the "requested state".  How do we make this
       happen?  The current implementation might also have a flaw here
       so maybe we log it as an issue for follow up.

> What do you mean by "add them to the journal"?

Use phosphor-logging.

-- 
Patrick Williams
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 801 bytes
Desc: Digital signature
URL: <http://lists.ozlabs.org/pipermail/openbmc/attachments/20170118/a3221e95/attachment.sig>