[PATCH 12/19] KVM: PPC: Book3S HV: record guest queue page address

[Cédric Le Goater]

On 2/4/19 6:15 AM, David Gibson wrote:
> On Mon, Jan 07, 2019 at 07:43:24PM +0100, Cédric Le Goater wrote:
>> The guest physical address of the event queue will be part of the
>> state to transfer in the migration. Cache its value when the queue is
>> configured, it will save us an OPAL call.
> 
> That doesn't sound like a very compelling case - migration is already
> a hundreds of milliseconds type operation, I wouldn't expect a few
> extra OPAL calls to be an issue.

OK. I don't think this is much a problem anyhow. Let's call OPAL.

C. 

 
>>
>> Signed-off-by: Cédric Le Goater <clg at kaod.org>
>> ---
>>  arch/powerpc/include/asm/xive.h       | 2 ++
>>  arch/powerpc/kvm/book3s_xive_native.c | 4 ++++
>>  2 files changed, 6 insertions(+)
>>
>> diff --git a/arch/powerpc/include/asm/xive.h b/arch/powerpc/include/asm/xive.h
>> index 7a7aa22d8258..e90c3c5d9533 100644
>> --- a/arch/powerpc/include/asm/xive.h
>> +++ b/arch/powerpc/include/asm/xive.h
>> @@ -74,6 +74,8 @@ struct xive_q {
>>  	u32			esc_irq;
>>  	atomic_t		count;
>>  	atomic_t		pending_count;
>> +	u64			guest_qpage;
>> +	u32			guest_qsize;
>>  };
>>  
>>  /* Global enable flags for the XIVE support */
>> diff --git a/arch/powerpc/kvm/book3s_xive_native.c b/arch/powerpc/kvm/book3s_xive_native.c
>> index 35d806740c3a..4ca75aade069 100644
>> --- a/arch/powerpc/kvm/book3s_xive_native.c
>> +++ b/arch/powerpc/kvm/book3s_xive_native.c
>> @@ -708,6 +708,10 @@ static int kvmppc_h_int_set_queue_config(struct kvm_vcpu *vcpu,
>>  	}
>>  	qaddr = page_to_virt(page) + (qpage & ~PAGE_MASK);
>>  
>> +	/* Backup queue page address and size for migration */
>> +	q->guest_qpage = qpage;
>> +	q->guest_qsize = qsize;
>> +
>>  	rc = xive_native_configure_queue(xc->vp_id, q, priority,
>>  					 (__be32 *) qaddr, qsize, true);
>>  	if (rc) {
>