Re: [PATCH V4 1/3] mm/sparsemem: Enable vmem_altmap support in vmemmap_populate_basepages()

[David Hildenbrand]

> Hmm, I assume these are some decisions that x86 platform will have to
> make going forward in a subsequent patch as the third patch does for
> the arm64 platform. But it is clearly beyond the scope of this patch
> which never intended to change existing behavior on a given platform.
> 

Yeah, I would be curious if my assumption is correct.

>>
>> [...]
>>
>>>  
>>> -pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node)
>>> +pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node,
>>> +				       struct vmem_altmap *altmap)
>>>  {
>>>  	pte_t *pte = pte_offset_kernel(pmd, addr);
>>>  	if (pte_none(*pte)) {
>>>  		pte_t entry;
>>> -		void *p = vmemmap_alloc_block_buf(PAGE_SIZE, node);
>>> +		void *p;
>>> +
>>> +		if (altmap)
>>> +			p = altmap_alloc_block_buf(PAGE_SIZE, altmap);
>>> +		else
>>> +			p = vmemmap_alloc_block_buf(PAGE_SIZE, node);
>>>  		if (!p)
>>>  			return NULL;
>>
>> I was wondering if
>>
>> if (altmap)
>> 	p = altmap_alloc_block_buf(PAGE_SIZE, altmap);
>> if (!p)
>> 	p = vmemmap_alloc_block_buf(PAGE_SIZE, node);
>> if (!p)
>> 	return NULL
>>
>> Would make sense. But I guess this isn't really relevant in practice,
>> because the altmap is usually sized properly.
>>
>> In general, LGTM.
> 
> Okay, I assume that no further changes are required here.
> 

Jep,

Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>

-- 
Thanks,

David / dhildenb