| Message ID | 1480433602-13290-16-git-send-email-boris.ostrovsky@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Nov 29, 2016 at 10:33:22AM -0500, Boris Ostrovsky wrote: > Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> > --- > CC: George Dunlap <George.Dunlap@eu.citrix.com> > CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> > CC: Stefano Stabellini <sstabellini@kernel.org> > CC: Tim Deegan <tim@xen.org> > --- > Changes in v4: > * Updated text to reflect new interfaces. > > docs/misc/hvmlite.markdown | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/docs/misc/hvmlite.markdown b/docs/misc/hvmlite.markdown > index 898b8ee..71c6bc2 100644 > --- a/docs/misc/hvmlite.markdown > +++ b/docs/misc/hvmlite.markdown > @@ -75,3 +75,16 @@ info structure that's passed at boot time (field rsdp_paddr). > > Description of paravirtualized devices will come from XenStore, just as it's > done for HVM guests. > + > +## VCPU hotplug ## > + > +VCPU hotplug (e.g. 'xl vcpu-set <domain> <num_vcpus>') for PVHv2 guests > +follows ACPI model where change in domain's number of VCPUS (stored in > +domain.avail_vcpus) results in an SCI being sent to the guest. The guest > +then executes DSDT's PRSC method, updating MADT enable status for the > +affected VCPU. > + > +This is achieved by having the toolstack issue a write to ACPI's > +XEN_ACPI_CPU_MAP (thus updating the VCPU available map stored there), > +followed by a write to ACPI GPE0 status register, setting XEN_GPE0_CPUHP_BIT. > +The latter will cause an SCI to be generated. > -- > 2.7.4 >
diff --git a/docs/misc/hvmlite.markdown b/docs/misc/hvmlite.markdown index 898b8ee..71c6bc2 100644 --- a/docs/misc/hvmlite.markdown +++ b/docs/misc/hvmlite.markdown @@ -75,3 +75,16 @@ info structure that's passed at boot time (field rsdp_paddr). Description of paravirtualized devices will come from XenStore, just as it's done for HVM guests. + +## VCPU hotplug ## + +VCPU hotplug (e.g. 'xl vcpu-set <domain> <num_vcpus>') for PVHv2 guests +follows ACPI model where change in domain's number of VCPUS (stored in +domain.avail_vcpus) results in an SCI being sent to the guest. The guest +then executes DSDT's PRSC method, updating MADT enable status for the +affected VCPU. + +This is achieved by having the toolstack issue a write to ACPI's +XEN_ACPI_CPU_MAP (thus updating the VCPU available map stored there), +followed by a write to ACPI GPE0 status register, setting XEN_GPE0_CPUHP_BIT. +The latter will cause an SCI to be generated.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> --- CC: George Dunlap <George.Dunlap@eu.citrix.com> CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> CC: Stefano Stabellini <sstabellini@kernel.org> CC: Tim Deegan <tim@xen.org> --- Changes in v4: * Updated text to reflect new interfaces. docs/misc/hvmlite.markdown | 13 +++++++++++++ 1 file changed, 13 insertions(+)