[PATCH 15/15] KVM: ARM: Guest wait-for-interrupts (WFI) support

[Christoffer Dall]

On Tue, Sep 25, 2012 at 1:04 PM, Will Deacon <will.deacon at arm.com> wrote:
> On Sat, Sep 15, 2012 at 04:36:05PM +0100, Christoffer Dall wrote:
>> From: Christoffer Dall <cdall at cs.columbia.edu>
>>
>> When the guest executes a WFI instruction the operation is trapped to
>> KVM, which emulates the instruction in software. There is no correlation
>> between a guest executing a WFI instruction and actually putting the
>> hardware into a low-power mode, since a KVM guest is essentially a
>> process and the WFI instruction can be seen as 'sleep' call from this
>> process. Therefore, we block the vcpu when the guest excecutes a wfi
>> instruction and the IRQ or FIQ lines are not raised.
>>
>> When an interrupt comes in through KVM_IRQ_LINE (see previous patch) we
>> signal the VCPU thread and unflag the VCPU to no longer wait for
>> interrupts.
>
> Seems a bit strange tagging this small addition on the end of this series.
> Can you merge it in with the rest?
>

sure, I'll tag it in with the world-switch or emulation.

-Christoffer