From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wei Liu <wei.liu2@citrix.com>
Subject: Re: [PATCH] docs: Specify VCPU hotplug procedure for
	HVMlite guests
Date: Wed, 3 Feb 2016 16:20:03 +0000
Message-ID: <20160203162003.GP23178@citrix.com>
References: <1454515899-1787-1-git-send-email-boris.ostrovsky@oracle.com>
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To: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: keir@xen.org, ian.campbell@citrix.com, tim@xen.org, ian.jackson@eu.citrix.com, xen-devel@lists.xen.org, jbeulich@suse.com, wei.liu2@citrix.com, roger.pau@citrix.com
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On Wed, Feb 03, 2016 at 11:11:39AM -0500, Boris Ostrovsky wrote:
> HVMlite VCPUs can be added and removed by toggling 'availability'
> value of VCPU's xenstore entry.
> 
> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
> ---
> 
> I am not sure this is really needed since it's no different from how we
> do hotplug for PV or HVM/qemu-trad guests.
> 

There is no harm to have more document. Not everyone who wants to
implement PVH support is familiar with PV and / or want to look at Linux
and libxl code (for various reasons). ;-)

Wei.

> I may have been a bit too grandiose by describing yesterday's patch as
> "add CPU hotplug support". It was really enabling existing functionality.
> 
>  docs/misc/hvmlite.markdown | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/docs/misc/hvmlite.markdown b/docs/misc/hvmlite.markdown
> index c1b75c6..1a2e866 100644
> --- a/docs/misc/hvmlite.markdown
> +++ b/docs/misc/hvmlite.markdown
> @@ -80,3 +80,8 @@ are used in order to bring up secondary vCPUs:
>   * `VCPUOP_down` is used to bring down a vCPU.
>  
>   * `VCPUOP_is_up` is used to scan the number of available vCPUs.
> +
> +## VCPU hotplug ##
> +
> +VCPUs can be hot-plugged or hot-removed by writing "online" or "offline" to
> +xenstore's /local/domain/<domain_id>/cpu/<vcpu_id>/availability entry
> -- 
> 2.1.0
>