Add collapse_allowable_orders() to generalize THP order eligibility. The function determines which THP orders are permitted based on collapse context (khugepaged vs madv_collapse).
This consolidates collapse configuration logic and provides a clean interface for future mTHP collapse support where the orders may be different. Reviewed-by: Baolin Wang <[email protected]> Signed-off-by: Nico Pache <[email protected]> --- mm/khugepaged.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 0dbbe04c31fe..89a105124790 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -489,7 +489,16 @@ static unsigned int collapse_max_ptes_none(unsigned int order, bool full_scan) max_ptes_none = min(khugepaged_max_ptes_none, HPAGE_PMD_NR/2 - 1); return max_ptes_none >> (HPAGE_PMD_ORDER - order); +} + +/* Check what orders are allowed based on the vma and collapse type */ +static unsigned long collapse_allowable_orders(struct vm_area_struct *vma, + vm_flags_t vm_flags, bool is_khugepaged) +{ + enum tva_type tva_flags = is_khugepaged ? TVA_KHUGEPAGED : TVA_FORCED_COLLAPSE; + unsigned long orders = BIT(HPAGE_PMD_ORDER); + return thp_vma_allowable_orders(vma, vm_flags, tva_flags, orders); } void khugepaged_enter_vma(struct vm_area_struct *vma, @@ -497,7 +506,7 @@ void khugepaged_enter_vma(struct vm_area_struct *vma, { if (!mm_flags_test(MMF_VM_HUGEPAGE, vma->vm_mm) && hugepage_pmd_enabled()) { - if (thp_vma_allowable_order(vma, vm_flags, TVA_KHUGEPAGED, PMD_ORDER)) + if (collapse_allowable_orders(vma, vm_flags, true)) __khugepaged_enter(vma->vm_mm); } } @@ -2567,7 +2576,7 @@ static unsigned int collapse_scan_mm_slot(unsigned int pages, int *result, progress++; break; } - if (!thp_vma_allowable_order(vma, vma->vm_flags, TVA_KHUGEPAGED, PMD_ORDER)) { + if (!collapse_allowable_orders(vma, vma->vm_flags, true)) { skip: progress++; continue; @@ -2873,7 +2882,7 @@ int madvise_collapse(struct vm_area_struct *vma, unsigned long start, BUG_ON(vma->vm_start > start); BUG_ON(vma->vm_end < end); - if (!thp_vma_allowable_order(vma, vma->vm_flags, TVA_FORCED_COLLAPSE, PMD_ORDER)) + if (!collapse_allowable_orders(vma, vma->vm_flags, false)) return -EINVAL; cc = kmalloc(sizeof(*cc), GFP_KERNEL); -- 2.51.0
