Re: [PATCH 1/1] mm/madvise: enhance lazyfreeing with mTHP in madvise_free

Ryan Roberts
2024-02-26T13:04:21Z

On 26/02/2024 08:55, Lance Yang wrote:
> Hey David,
>
> Thanks for your suggestion!
>
> On Mon, Feb 26, 2024 at 4:41 PM David Hildenbrand <david@redhat.com> wrote:
>>
> [...]
>>> On Mon, Feb 26, 2024 at 12:00 PM Barry Song <21cnbao@gmail.com> wrote:
>>> [...]
>>>> On Mon, Feb 26, 2024 at 1:33 AM Lance Yang <ioworker0@gmail.com> wrote:
>>> [...]
> [...]
>>> +static inline bool pte_range_cont_mapped(pte_t *pte, unsigned long nr)
>>> +{
>>> + pte_t pte_val;
>>> + unsigned long pfn = pte_pfn(pte);
>>> + for (int i = 0; i < nr; i++) {
>>> + pte_val = ptep_get(pte + i);
>>> + if (pte_none(pte_val) || pte_pfn(pte_val) != (pfn + i))
>>> + return false;
>>> + }
>>> + return true;
>>> +}
>>
>> I dislike the "cont mapped" terminology.
>>
>> Maybe folio_pte_batch() does what you want?
>
> folio_pte_batch() is a good choice. Appreciate it!

Agreed, folio_pte_batch() is likely to be widely useful for this change and
others, so suggest exporting it from memory.c and reusing as is if possible.

>
> Best,
> Lance
>
>>
>> --
>> Cheers,
>>
>> David / dhildenb
>>