Re: [Xen-devel] [PATCHv2 10/10] xen/balloon: pre-allocate p2m entries for ballooned pages

From: David Vrabel
Date: Mon Jul 27 2015 - 08:40:14 EST


On 27/07/15 12:01, Julien Grall wrote:
> On 27/07/15 10:30, David Vrabel wrote:
>> On 25/07/15 00:21, Julien Grall wrote:
>>> On 24/07/2015 12:47, David Vrabel wrote:
>>>> @@ -550,6 +551,11 @@ int alloc_xenballooned_pages(int nr_pages, struct
>>>> page **pages)
>>>> page = balloon_retrieve(true);
>>>> if (page) {
>>>> pages[pgno++] = page;
>>>> +#ifdef CONFIG_XEN_HAVE_PVMMU
>>>> + ret = xen_alloc_p2m_entry(page_to_pfn(page));
>>>
>>> Don't you want to call this function only when the guest is not using
>>> auto-translated physmap?
>>
>> xen_alloc_p2m_entry() is a nop in auto-xlate guests, so no need for an
>> additional check here.
>
> I don't have the impression it's the case or it's not obvious.

Oops. You're right. I'll add a

if (xen_feature(XENFEAT_auto_translated_physmap))
return true;

Check at the top.

David

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/