[RFC PATCH 03/12] khugepaged: Generalize hugepage_vma_revalidate()

From: Dev Jain
Date: Mon Dec 16 2024 - 11:58:29 EST


Post retaking the lock, it must be checked that the VMA is suitable for our
scan order. Hence, generalize hugepage_vma_revalidate().

Signed-off-by: Dev Jain <dev.jain@xxxxxxx>
---
mm/khugepaged.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 02cd424b8e48..2f0601795471 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -918,7 +918,7 @@ static int hpage_collapse_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 vm_area_struct **vmap, int order,
struct collapse_control *cc)
{
struct vm_area_struct *vma;
@@ -931,9 +931,9 @@ static int hugepage_vma_revalidate(struct mm_struct *mm, unsigned long address,
if (!vma)
return SCAN_VMA_NULL;

- if (!thp_vma_suitable_order(vma, address, PMD_ORDER))
+ if (!thp_vma_suitable_order(vma, address, order))
return SCAN_ADDRESS_RANGE;
- if (!thp_vma_allowable_order(vma, vma->vm_flags, tva_flags, PMD_ORDER))
+ if (!thp_vma_allowable_order(vma, vma->vm_flags, tva_flags, order))
return SCAN_VMA_CHECK;
/*
* Anon VMA expected, the address may be unmapped then
@@ -1134,7 +1134,7 @@ 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, order, cc);
if (result != SCAN_SUCCEED) {
mmap_read_unlock(mm);
goto out_nolock;
@@ -1168,7 +1168,7 @@ 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, order, cc);
if (result != SCAN_SUCCEED)
goto out_up_write;
/* check if the pmd is still valid */
@@ -2776,7 +2776,7 @@ int madvise_collapse(struct vm_area_struct *vma, struct vm_area_struct **prev,
mmap_read_lock(mm);
mmap_locked = true;
result = hugepage_vma_revalidate(mm, addr, false, &vma,
- cc);
+ HPAGE_PMD_ORDER, cc);
if (result != SCAN_SUCCEED) {
last_fail = result;
goto out_nolock;
--
2.30.2