Re: [PATCH v9 3/4] mm/memory: add any_dirty optional pointer to folio_pte_batch()

From: David Hildenbrand
Date: Thu Apr 18 2024 - 08:01:46 EST


On 18.04.24 12:57, Lance Yang wrote:
This commit adds the any_dirty pointer as an optional parameter to
folio_pte_batch() function. By using both the any_young and any_dirty pointers,
madvise_free can make smarter decisions about whether to clear the PTEs when
marking large folios as lazyfree.

Suggested-by: David Hildenbrand <david@xxxxxxxxxx>
Signed-off-by: Lance Yang <ioworker0@xxxxxxxxx>
---
mm/internal.h | 12 ++++++++++--
mm/madvise.c | 19 ++++++++++++++-----
mm/memory.c | 4 ++--
3 files changed, 26 insertions(+), 9 deletions(-)

diff --git a/mm/internal.h b/mm/internal.h
index c6483f73ec13..daa59cef85d7 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -134,6 +134,8 @@ static inline pte_t __pte_batch_clear_ignored(pte_t pte, fpb_t flags)
* first one is writable.
* @any_young: Optional pointer to indicate whether any entry except the
* first one is young.
+ * @any_dirty: Optional pointer to indicate whether any entry except the
+ * first one is dirty.
*

I was also wondering if we should make that function return a pte+nr_pages, instead of only nr_pages, and then simply have the function, based on new flags, merge data into the original PTE.

But let's do that separately.

Acked-by: David Hildenbrand <david@xxxxxxxxxx>

--
Cheers,

David / dhildenb