Re: [PATCH] mm/khugepaged: use [pmd|pte]_addr for better reading

[Wei Yang <richard.weiyang@gmail.com>]

On Sat, Sep 20, 2025 at 12:30:52PM +0800, Lance Yang wrote:
>
>On 2025/9/20 08:54, Wei Yang wrote:
>> When collapse a pmd, there are two address in use:
>> 
>>    * address points to the start of pmd
>>    * address points to each individual page
>> 
>> Current naming is not easy to distinguish these two and error prone.
>> 
>> Name the first one to pmd_addr and second one to pte_addr.
>> 
>> Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
>> Suggested-by: David Hildenbrand <david@redhat.com>
>
>This renaming makes the code much easier to follow, but just
>some minor style nits below :)
>
>Acked-by: Lance Yang <lance.yang@linux.dev>
>
>> ---
>>   mm/khugepaged.c | 43 ++++++++++++++++++++++---------------------
>>   1 file changed, 22 insertions(+), 21 deletions(-)
>> 
>> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
>> index 4c957ce788d1..6d03072c1a92 100644
>> --- a/mm/khugepaged.c
>> +++ b/mm/khugepaged.c
>> @@ -537,18 +537,19 @@ static void release_pte_pages(pte_t *pte, pte_t *_pte,
>>   }
>>   static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
>> -					unsigned long address,
>> +					unsigned long pmd_addr,
>>   					pte_t *pte,
>>   					struct collapse_control *cc,
>>   					struct list_head *compound_pagelist)
>>   {
>>   	struct page *page = NULL;
>>   	struct folio *folio = NULL;
>> +	unsigned long pte_addr = pmd_addr;
>>   	pte_t *_pte;
>>   	int none_or_zero = 0, shared = 0, result = SCAN_FAIL, referenced = 0;
>
>Nit: could we refactor this block into the "reverse christmas tree" style?
>

You mean sth like this?

   	int none_or_zero = 0, shared = 0, result = SCAN_FAIL, referenced = 0;
   	struct page *page = NULL;
   	struct folio *folio = NULL;
  	unsigned long pte_addr = pmd_addr;
   	pte_t *_pte;

-- 
Wei Yang
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