Re: [RFC 02/11] mm/migrate_device: flags for selecting device private THP pages

[Balbir Singh <balbirs@nvidia.com>]

On 7/8/25 23:41, David Hildenbrand wrote:
> On 06.03.25 05:42, Balbir Singh wrote:
>> Add flags to mark zone device migration pages.
>>
>> MIGRATE_VMA_SELECT_COMPOUND will be used to select THP pages during
>> migrate_vma_setup() and MIGRATE_PFN_COMPOUND will make migrating
>> device pages as compound pages during device pfn migration.
>>
>> Signed-off-by: Balbir Singh <balbirs@nvidia.com>
>> ---
>>   include/linux/migrate.h | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/include/linux/migrate.h b/include/linux/migrate.h
>> index 61899ec7a9a3..b5e4f51e64c7 100644
>> --- a/include/linux/migrate.h
>> +++ b/include/linux/migrate.h
>> @@ -167,6 +167,7 @@ static inline int migrate_misplaced_folio(struct folio *folio, int node)
>>   #define MIGRATE_PFN_VALID    (1UL << 0)
>>   #define MIGRATE_PFN_MIGRATE    (1UL << 1)
>>   #define MIGRATE_PFN_WRITE    (1UL << 3)
>> +#define MIGRATE_PFN_COMPOUND    (1UL << 4)
>>   #define MIGRATE_PFN_SHIFT    6
>>     static inline struct page *migrate_pfn_to_page(unsigned long mpfn)
>> @@ -185,6 +186,7 @@ enum migrate_vma_direction {
>>       MIGRATE_VMA_SELECT_SYSTEM = 1 << 0,
>>       MIGRATE_VMA_SELECT_DEVICE_PRIVATE = 1 << 1,
>>       MIGRATE_VMA_SELECT_DEVICE_COHERENT = 1 << 2,
>> +    MIGRATE_VMA_SELECT_COMPOUND = 1 << 3,
>>   };
>>     struct migrate_vma {
> 
> Squash that into the patch where it is actually used.
> 

Will do,

Thanks,
Balbir Singh