Virtualization - Dec 2021 - [PATCH v1 2/2] virtio-mem: prepare fake page onlining code for granularity smaller than MAX_ORDER - 1

Hi Eric,

thanks for the review!
>>   		if (PageDirty(page)) {
>> -			virtio_mem_clear_fake_offline(pfn + i, max_nr_pages,
>> -						      false);
>> -			generic_online_page(page, MAX_ORDER - 1);
>> +			virtio_mem_clear_fake_offline(pfn + i, 1 << order, false);
>> +			generic_online_page(page, order);
>>   		} else {
>> -			virtio_mem_clear_fake_offline(pfn + i, max_nr_pages,
>> -						      true);
>> -			free_contig_range(pfn + i, max_nr_pages);
>> -			adjust_managed_page_count(page, max_nr_pages);
>> +			virtio_mem_clear_fake_offline(pfn + i, 1 << order, true);
>> +			free_contig_range(pfn + i, 1 << order);
>> +			adjust_managed_page_count(page, 1 << order);
> In the loop, pfn + i, 1 << order are repeatedly calculated. 1
<< order
> is a step size, pfn + i? is each step position.
> Better to figure the numer once each iter?
The compiler better be smart enough to calculate such constants once :)
> 
> LGTL.
> LGTM.
> Reviewed-by: Eric Ren <renzhengeek at gmail.com>
Thanks!


-- 
Thanks,

David / dhildenb