Re: [OSSTEST Nested PATCH v11 6/7] Compose the main recipe of nested test job

[Ian Campbell <ian.campbell@citrix.com>]

On Tue, 2015-08-18 at 06:46 +0000, Hu, Robert wrote:

Sorry for the delay, I've been away.

> > -----Original Message-----
> > From: Ian Jackson [mailto:Ian.Jackson@eu.citrix.com]
> > Sent: Thursday, June 25, 2015 6:22 PM
> > To: Pang, LongtaoX
> > Cc: Ian Campbell; Hu, Robert; xen-devel@lists.xen.org; 
> > wei.liu2@citrix.com
> > Subject: RE: [OSSTEST Nested PATCH v11 6/7] Compose the main recipe of
> > nested test job
> > 
> > Pang, LongtaoX writes ("RE: [OSSTEST Nested PATCH v11 6/7] Compose the
> > main recipe of nested test job"):
> > > > -----Original Message-----
> > > > From: Ian Campbell [mailto:ian.campbell@citrix.com]
> > ...
> > > > I think you are correct, the logs capture will fail too.
> > > > 
> > > > I'll leave it to Ian to suggest a solution since it will no doubt
> > > > involve some tcl plumbing (I'd be inclined to record 'hosts which 
> > > > are
> > > > actually guests' somewhere and have the infra clean them up
> > > > automatically after doing leak check and log collection).
> > 
> > Sorry I haven't done this yet, it's still on my radar.
> > 
> > > > I was thinking more along the lines of creating 
> > > > Osstest/PDU/guest.pm
> > > > with the appropriate methods calling out to toolstack($l0)->foo, 
> > > > setting
> > > > $ho->{Power} = 'guest $l1guestname' somewhere and allowing
> > > > power_cycle_host_setup to do it's thing.
> > > 
> > > I have reviewed power_cycle_host_setup function, inside this
> > > function will call get_host_method_object, then we could get a $mo
> > > which will be assigned to $ho->{PowerMethobjs}, right?  Inside
> > > power_state function, it will call pdu_power_state which is defined
> > > in guest.pm, right?
> > 
> > Yes.
> I'm not quite sure about how @$methobjs is obtained.
> sub power_cycle_host_setup ($) {
>     my ($ho) = @_;
>     my $methobjs = [ ];
>     foreach my $meth (split /\;\s*/, $ho->{Power}) {
> 	push @$methobjs, get_host_method_object($ho,'PDU',$meth);
>     }
>     $ho->{PowerMethobjs} = $methobjs;
> }
> Seems it is derived from $ho->{Power} while $ho->{Power} is defined by 
> either:
> 1. selecthost()
> 	$ho->{Power}= get_host_property($ho,'power-method');
> 2. default_methods()
> 	$ho->{Power} ||= "statedb $ho->{Asset}";
>   Seems no statedb for standalone mode.

Indeed, statedb is actually peculiar to the old Cambridge instance of
osstest, it's not used in the production colo. In fact it is also not used
in Cambridge any more, every host has a power-method host property. In
standalone mode the default {Power} is "manual" I think, that's the one
which prompts you to press a key.

The {Power} property is essentially a ";" separated list, each list entry
is "<module> <arg1> <arg2> <...>". <module> is Osstest/PDU/<module>.pm and
<arg1> <arg2> <...> are passed to the constructor. These objects are
constructed by get_host_method_object.

Then on power operation the appropriate method each object is called in
turn (so you can call multiple modules if needed by the host).

> So how shall I assign $ho->{Power} method? by statically through config
> file?
> or some generic way automatically identify $host is some guest, therefore
> assign 'guest' to $ho->{Power}?
> Would you give me some idea? thanks.

I'm not sure. Something in selecthost would need to know somehow that the
host being requested was actually an L1 guest.

Ian, any ideas?

Ian