On Mon, 20 Jul 2026 12:47:23 +0300 Gutierrez Asier <[email protected]> wrote:
> > > On 7/20/2026 6:03 AM, Lian Wang wrote: > > Add a new DAMOS action, DAMOS_SPLIT, that splits large folios in the > > target region down to a smaller order. A new per-scheme field and sysfs > > file, target_order, selects the split target: 0 for order-0 base pages, > > or 2..HPAGE_PMD_ORDER-1 for a smaller mTHP order (order-1 is rejected at > > store time since anonymous THPs cannot be split to order-1). > > > > Unlike DAMOS_COLLAPSE which builds large folios, splitting only dismantles > > them; it allocates nothing, copies nothing, and no THP admission policy > > applies. khugepaged deliberately refuses to collapse a folio to a > > smaller order, leaving the shrink direction to callers like this one. > > > > This patch adds the DAMOS_SPLIT action, the ``order`` field (placed in > > the existing union alongside target_nid and migrate_dests), its sysfs > > interface, and documentation. The vaddr operations set handler is added > > in the next patch. > > > > Link: https://lore.kernel.org/[email protected]/ > > ("mm/khugepaged: skip collapsing mTHP to smaller orders") Hi Asier, Thanks for the review. All three points noted -- will address them in the next revision along with feedback from David and others. Thanks, Lian Wang
