Re: [v2 00/16] mm: PMD-level swap entries for anonymous THPs

From: Usama Arif

Date: Sat Jun 13 2026 - 15:48:52 EST




On 13/06/2026 20:34, Usama Arif wrote:
>
>
> On 13/06/2026 20:27, Zi Yan wrote:
>> On 9 Jun 2026, at 10:29, Usama Arif wrote:
>>
>>> On 02/06/2026 15:24, Usama Arif wrote:
>>>> When reclaim swaps out a PMD-mapped anonymous THP today, the PMD is
>>>> split into 512 PTE-level swap entries via TTU_SPLIT_HUGE_PMD before
>>>> unmap.
>>>>
>>>> This series introduces a PMD-level swap entry. The huge mapping is
>>>> preserved across the swap round-trip, and do_huge_pmd_swap_page()
>>>> resolves the entire 2 MB region in a single fault on swap-in,
>>>> no khugepaged involvement is needed. swap_map metadata is identical
>>>> either way (512 single-slot counts), so the PTE split buys nothing
>>>> on the swap side, it is purely a page-table representation change.
>>>>
>>>
>>> Hello!
>>>
>>> Just following up if there were any reviews/comments on this series!
>>>
>>> I know its a large series but was just checking if there was any
>>> feedback?
>>
>> Maybe send first 6 clean-up patches separately to get them merged first?
>
> Good idea! Will do that. Thanks!
>

So what I will do is once the merge window closes, send the first 6 patches
for review, then when they make it into mm-new (so that we get sashiko feedback),
send the core patches that I have reworked based on Lances' feedback. [1] [2]

[1] https://lore.kernel.org/all/526fdbc0-1944-4328-9ff6-7922d021828d@xxxxxxxxx/
[2] https://lore.kernel.org/all/20260612142124.73367-1-lance.yang@xxxxxxxxx/