Re: [PATCH v2 01/13] mm/memory-failure: simplify put_ref_page()

From: Miaohe Lin
Date: Thu Jun 06 2024 - 23:28:52 EST


On 2024/6/6 14:46, Kefeng Wang wrote:
>
>
> On 2024/6/6 14:32, Miaohe Lin wrote:
>> Remove unneeded page != NULL check. pfn_to_page() won't return NULL.
>> No functional change intended.
>>
>> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
>> ---
>>   mm/memory-failure.c | 6 +-----
>>   1 file changed, 1 insertion(+), 5 deletions(-)
>>
>> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
>> index f679b579d45d..2e6038c73119 100644
>> --- a/mm/memory-failure.c
>> +++ b/mm/memory-failure.c
>> @@ -2120,14 +2120,10 @@ static inline unsigned long folio_free_raw_hwp(struct folio *folio, bool flag)
>>   /* Drop the extra refcount in case we come from madvise() */
>>   static void put_ref_page(unsigned long pfn, int flags)
>
> Since all calllers have a valid page,better to pass the page instead of pfn?

Seems not. put_ref_page() called above memory_failure_dev_pagemap() seems don't have a valid page yet.
Also page might be NULL when calling put_ref_page() in soft_offline_page(). So it should be better to
still pass pfn. Or am I miss something?

Thanks.
.