When an mm with the MMF_DISABLE_THP_COMPLETELY flag is detected during
scanning, directly set khugepaged_scan.mm_slot to the next mm_slot,
reduce redundant operation.

Without this patch, entering khugepaged_scan_mm_slot() next time, we
will set khugepaged_scan.mm_slot to the next mm_slot.

With this patch, we will directly set khugepaged_scan.mm_slot to the
next mm_slot.

Signed-off-by: Vernon Yang <yanglincheng@kylinos.cn>
---
 mm/khugepaged.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 8a7008760566..4c055d6c2717 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -2566,7 +2566,7 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, enum scan_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(mm) || !vma) {
+	if (hpage_collapse_test_exit_or_disable(mm) || !vma) {
 		/*
 		 * Make sure that if mm_users is reaching zero while
 		 * khugepaged runs here, khugepaged_exit will find
-- 
2.51.0

On 1/11/26 13:19, Vernon Yang wrote:
> When an mm with the MMF_DISABLE_THP_COMPLETELY flag is detected during
> scanning, directly set khugepaged_scan.mm_slot to the next mm_slot,
> reduce redundant operation.
> 
> Without this patch, entering khugepaged_scan_mm_slot() next time, we
> will set khugepaged_scan.mm_slot to the next mm_slot.
> 
> With this patch, we will directly set khugepaged_scan.mm_slot to the
> next mm_slot.
> 
> Signed-off-by: Vernon Yang <yanglincheng@kylinos.cn>
> ---
>   mm/khugepaged.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index 8a7008760566..4c055d6c2717 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -2566,7 +2566,7 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, enum scan_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(mm) || !vma) {
> +	if (hpage_collapse_test_exit_or_disable(mm) || !vma) {
>   		/*
>   		 * Make sure that if mm_users is reaching zero while
>   		 * khugepaged runs here, khugepaged_exit will find

collect_mm_slot() should do the right thing when disabled and just keep 
it on the list.

So this LGTM

Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>

-- 
Cheers

David

On 2026/1/11 20:19, Vernon Yang wrote:
> When an mm with the MMF_DISABLE_THP_COMPLETELY flag is detected during
> scanning, directly set khugepaged_scan.mm_slot to the next mm_slot,
> reduce redundant operation.
> 
> Without this patch, entering khugepaged_scan_mm_slot() next time, we
> will set khugepaged_scan.mm_slot to the next mm_slot.
> 
> With this patch, we will directly set khugepaged_scan.mm_slot to the
> next mm_slot.
> 
> Signed-off-by: Vernon Yang <yanglincheng@kylinos.cn>
> ---

Thanks! LGTM, so

Reviewed-by: Lance Yang <lance.yang@linux.dev>

>   mm/khugepaged.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index 8a7008760566..4c055d6c2717 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -2566,7 +2566,7 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, enum scan_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(mm) || !vma) {
> +	if (hpage_collapse_test_exit_or_disable(mm) || !vma) {
>   		/*
>   		 * Make sure that if mm_users is reaching zero while
>   		 * khugepaged runs here, khugepaged_exit will find