On Mon, Feb 26, 2024 at 7:51 PM Lance Yang <ioworker0@xxxxxxxxx> wrote:
>
> Previously, we removed the mm from mm_slot and dropped mm_count
> if the MMF_THP_DISABLE flag was set. However, we didn't re-add
> the mm back after clearing the MMF_THP_DISABLE flag. Additionally,
> We add a check for the MMF_THP_DISABLE flag in hugepage_vma_revalidate().
>
> Fixes: 879c6000e191 ("mm/khugepaged: bypassing unnecessary scans with MMF_DISABLE_THP check")
I think Andrew will fold this fix into your original patch.
>
> Signed-off-by: Lance Yang <ioworker0@xxxxxxxxx>
> Suggested-by: Yang Shi <shy828301@xxxxxxxxx>
Reviewed-by: Yang Shi <shy828301@xxxxxxxxx>
> ---
> mm/khugepaged.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index 2771fc043b3b..1c0073daad82 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -920,7 +920,7 @@ static int hugepage_vma_revalidate(struct mm_struct *mm, unsigned long address,
> {
> struct vm_area_struct *vma;
>
> - if (unlikely(hpage_collapse_test_exit(mm)))
> + if (unlikely(hpage_collapse_test_exit_or_disable(mm)))
> return SCAN_ANY_PROCESS;
>
> *vmap = vma = find_vma(mm, address);
> @@ -1428,7 +1428,7 @@ static void collect_mm_slot(struct khugepaged_mm_slot *mm_slot)
>
> lockdep_assert_held(&khugepaged_mm_lock);
>
> - if (hpage_collapse_test_exit_or_disable(mm)) {
> + if (hpage_collapse_test_exit(mm)) {
> /* free mm_slot */
> hash_del(&slot->hash);
> list_del(&slot->mm_node);
> @@ -2456,7 +2456,7 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, int *result,
> * Release the current mm_slot if this mm is about to die, or
> * if we scanned all vmas of this mm.
> */
> - if (hpage_collapse_test_exit_or_disable(mm) || !vma) {
> + if (hpage_collapse_test_exit(mm) || !vma) {
> /*
> * Make sure that if mm_users is reaching zero while
> * khugepaged runs here, khugepaged_exit will find
> --
> 2.33.1
>
