On Wed, Jun 10, 2026 at 06:29:12PM +0800, Baolin Wang wrote:
[...]
>@@ -2768,15 +2827,23 @@ static enum scan_result collapse_scan_file(struct
>mm_struct *mm,
> else
> cc->progress += HPAGE_PMD_NR;
>
>- if (result == SCAN_SUCCEED) {
>- if (present < HPAGE_PMD_NR - max_ptes_none) {
>- result = SCAN_EXCEED_NONE_PTE;
>- count_vm_event(THP_SCAN_EXCEED_NONE_PTE);
>- } else {
>- result = collapse_file(mm, addr, file, start, cc,
>HPAGE_PMD_ORDER);
>- }
>+ if (result != SCAN_SUCCEED)
>+ goto out;
>+
>+ if (present < HPAGE_PMD_NR - max_ptes_none) {
>+ result = SCAN_EXCEED_NONE_PTE;
>+ count_vm_event(THP_SCAN_EXCEED_NONE_PTE);
>+ count_mthp_stat(HPAGE_PMD_ORDER,
>+ MTHP_STAT_COLLAPSE_EXCEED_NONE);
>+ goto out;
> }
>
>+ result = mthp_collapse(mm, file, start, addr, 0, 0, cc, enabled_orders);
Feels like the second 0 wants to be "swap", no?
>+ if (result == SCAN_SUCCEED && !cc->is_khugepaged) {
>+ /* If MADV_COLLAPSE, adjust result to call
>collapse_pte_mapped_thp(). */
>+ result = SCAN_PTE_MAPPED_HUGEPAGE;
>+ }
>+out:
> trace_mm_khugepaged_scan_file(mm, folio, file, present, swap, result);
> return result;
> }
>@@ -2808,7 +2875,7 @@ static enum scan_result collapse_single_pmd(unsigned
>long addr,
> mmap_read_unlock(mm);
> *lock_dropped = true;
> retry:
>- result = collapse_scan_file(mm, addr, file, pgoff, cc);
>+ result = collapse_scan_file(mm, vma, addr, file, pgoff, cc);
>
> /*
> * For MADV_COLLAPSE, when encountering dirty pages, try to writeback,
>--
>2.47.3
>
>
