Re: [Xen-devel] Relationship between GuestOS shutdown and destroy operations?

[Ian Campbell <Ian.Campbell@xxxxxxxxxx>]

On Fri, 2012-09-21 at 05:35 +0100, Bruce Granger wrote:
> Hello everyone!

Hello.

Please don't spam the list by resending effectively the same question 3
times in less than 1.5 hours. The xen-devel list membership is spread
over multiple time zones, so please leave enough time for people to
actually receive and digest your mails. Also be remember that you asking
people to take time out from whatever they are doing to reply to you and
they may not do so straight away.

Also please keep things in the same thread (you have started three
separate threads today) and remember quote from previous mails where
appropriate.

I recommend subscribing the list directly rather than using nabble since
that service tends to encourage quite poor netiquette.

You might find it useful to read
http://wiki.xen.org/wiki/Asking_Xen_Devel_Questions

> In my opinion, I think when we shutdown the GuestOS,
>  Xen should free allocated vcpu and domain gived to GuestOS 
> when it created at the same time. 

shutdown is a guest driven operation while destroy is toolstack driven.

The flow is that the guest shuts itself down (either by using PV
interfaces, SCHEDOP_shutdown or emulated means such as halting all
processors with interrupts disabled or via ACPI etc). This then causes a
signal to the toolstack which will then initiate the destroy, which
causes the hypervisor to finally teardown all the resources.

The signal to the toolstack is VIRQ_DOM_EXC which is received by the
xenstore daemon which then raises a watch called @releaseDomain. The
toolstack is watching for this and will initiate the final teardown of
the domain (or reboot it, or take a crash dump of its memory, or suspend
it, etc, as appropriate).

Ian.

> 
> But I donât find any code in functions associated with shutdown process to
> show this work,
> for example: 
> Hvm_vcpu_down()-ãdomain_shutdown()->__domain_finalise_shutdown()
> 
> But I find the functions free_vcpu_struct() and free_domain_struct() 
> in the function complete_domain_destroy() in the process of destroy
> operation, 
> the code process is:
> Domain_kill()->put_domain()->domain_destroy()->complete_domain_destroy()
> 
> Is that process right? Is there any relationship between them?
> Does anyone know it?
> 
> Thanks for your help!
> 
> 
> 
> --
> View this message in context: 
> http://xen.1045712.n5.nabble.com/Relationship-between-GuestOS-shutdown-and-destroy-operations-tp5711423.html
> Sent from the Xen - Dev mailing list archive at Nabble.com.
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxx
> http://lists.xen.org/xen-devel



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel