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Date:   Tue, 28 Jun 2022 11:17:32 +0530
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Subject: Re: [PATCH] mm: hugetlb: kill set_huge_swap_pte_at()
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To:     Matthew Wilcox <willy@infradead.org>
Cc:     Qi Zheng <zhengqi.arch@bytedance.com>, mike.kravetz@oracle.com,
        songmuchun@bytedance.com, akpm@linux-foundation.org,
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From:   Anshuman Khandual <anshuman.khandual@arm.com>
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On 6/27/22 20:04, Matthew Wilcox wrote:
> On Mon, Jun 27, 2022 at 01:05:00PM +0530, Anshuman Khandual wrote:
>>> For the swap entry of hugetlb, we need to remember that we should
>>> call set_huge_swap_pte_at() instead of set_huge_pte_at() every
>>
>> Which is intuitive, so what is the problem ?
> 
> The problem is that HugeTLB is DIFFERENT from the rest of the VM.

Agreed.

> This has a huge cost in programmer time, which is infinitely more
> valuable than the cycle shaving you're quibbling over.  We should take
> any and every opportunity to make huge pages work the same way as THP
> and order-0 pages.

Got it.