Re: [RFC PATCH v4 3/6] mm/migrate: add batch-copy path in migrate_pages_batch

[Garg, Shivank]

On 3/24/2026 2:12 PM, Huang, Ying wrote:
> Shivank Garg <shivankg@xxxxxxx> writes:
> 

>> -	LIST_HEAD(unmap_folios);
>> -	LIST_HEAD(dst_folios);
>> +	unsigned int nr_batch = 0;
>> +	bool batch_copied = false;
>> +	LIST_HEAD(src_batch);
>> +	LIST_HEAD(dst_batch);
>> +	LIST_HEAD(src_std);
>> +	LIST_HEAD(dst_std);
> 
> IMHO, the naming appears too copy centric, how about unmap_batch and
> unmap_single?  "unmap" is one step of migration.
> 
Makes sense, I'll rename them to unmap_batch/unmap_single/dst_single.

>>  	bool nosplit = (reason == MR_NUMA_MISPLACED);
>>  
>>  	VM_WARN_ON_ONCE(mode != MIGRATE_ASYNC &&
>> @@ -1943,7 +1956,7 @@ static int migrate_pages_batch(struct list_head *from,
> 
> unmap/dst_folios  in comments need to be changed too.
> 
> 			rc = migrate_folio_unmap(get_new_folio, put_new_folio,
> 					private, folio, &dst, mode, ret_folios);
> 			/*
> 			 * The rules are:
> 			 *	0: folio will be put on unmap_folios list,
> 			 *	   dst folio put on dst_folios list
> 			 *	-EAGAIN: stay on the from list
> 			 *	-ENOMEM: stay on the from list
> 			 *	Other errno: put on ret_folios list
> 			 */
> 
> 

yes, will update these comments.

Best regards,
Shivank