For khugepaged to support different mTHP orders, we must generalize this
to check if the PMD is not shared by another VMA and the order is enabled.
To ensure madvise_collapse can support working on mTHP orders without the
PMD order enabled, we need to convert hugepage_vma_revalidate to take a
bitmap of orders.
No functional change in this patch.
Reviewed-by: Baolin Wang <baolin.w...@linux.alibaba.com>
Co-developed-by: Dev Jain <dev.j...@arm.com>
Signed-off-by: Dev Jain <dev.j...@arm.com>
Signed-off-by: Nico Pache <npa...@redhat.com>
---
mm/khugepaged.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index bf69e81a3d82..7bcd4d280c71 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -907,7 +907,7 @@ static int khugepaged_find_target_node(struct
collapse_control *cc)
static int hugepage_vma_revalidate(struct mm_struct *mm, unsigned long address,
bool expect_anon,
struct vm_area_struct **vmap,
- struct collapse_control *cc)
+ struct collapse_control *cc, unsigned long
orders)
{
struct vm_area_struct *vma;
unsigned long tva_flags = cc->is_khugepaged ? TVA_ENFORCE_SYSFS : 0;
@@ -919,9 +919,10 @@ static int hugepage_vma_revalidate(struct mm_struct *mm,
unsigned long address,
if (!vma)
return SCAN_VMA_NULL;
+ /* Always check the PMD order to insure its not shared by another VMA */
if (!thp_vma_suitable_order(vma, address, PMD_ORDER))
return SCAN_ADDRESS_RANGE;
- if (!thp_vma_allowable_order(vma, vma->vm_flags, tva_flags, PMD_ORDER))
+ if (!thp_vma_allowable_orders(vma, vma->vm_flags, tva_flags, orders))
return SCAN_VMA_CHECK;
/*
* Anon VMA expected, the address may be unmapped then
@@ -1115,7 +1116,8 @@ static int collapse_huge_page(struct mm_struct *mm,
unsigned long address,
goto out_nolock;
mmap_read_lock(mm);
- result = hugepage_vma_revalidate(mm, address, true, &vma, cc);
+ result = hugepage_vma_revalidate(mm, address, true, &vma, cc,
+ BIT(HPAGE_PMD_ORDER));
if (result != SCAN_SUCCEED) {
mmap_read_unlock(mm);
goto out_nolock;
@@ -1149,7 +1151,8 @@ static int collapse_huge_page(struct mm_struct *mm,
unsigned long address,
* mmap_lock.
*/
mmap_write_lock(mm);
- result = hugepage_vma_revalidate(mm, address, true, &vma, cc);
+ result = hugepage_vma_revalidate(mm, address, true, &vma, cc,
+ BIT(HPAGE_PMD_ORDER));
if (result != SCAN_SUCCEED)
goto out_up_write;
/* check if the pmd is still valid */
@@ -2780,7 +2783,7 @@ int madvise_collapse(struct vm_area_struct *vma, unsigned
long start,
mmap_read_lock(mm);
mmap_locked = true;
result = hugepage_vma_revalidate(mm, addr, false, &vma,
- cc);
+ cc,
BIT(HPAGE_PMD_ORDER));
if (result != SCAN_SUCCEED) {
last_fail = result;
goto out_nolock;
--
2.49.0
