Re: [PATCH v8 2/7] mm: introduce clear_pages() and clear_user_pages()

From: David Hildenbrand (Red Hat)

Date: Tue Nov 18 2025 - 02:36:10 EST


On 27.10.25 21:21, Ankur Arora wrote:
Introduce clear_pages(), to be overridden by architectures that
support more efficient clearing of consecutive pages.

Also introduce clear_user_pages(), however, we will not expect
this function to be overridden anytime soon.

We have to place the clear_user_pages() variant that uses
clear_user_page() into mm/util.c for now to work around
macro magic on sparc and m68k.

Signed-off-by: Ankur Arora <ankur.a.arora@xxxxxxxxxx>
---
include/linux/mm.h | 41 +++++++++++++++++++++++++++++++++++++++++
mm/util.c | 13 +++++++++++++
2 files changed, 54 insertions(+)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 683168b522b3..ecbcb76df9de 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -3872,6 +3872,26 @@ static inline void clear_page_guard(struct zone *zone, struct page *page,
unsigned int order) {}
#endif /* CONFIG_DEBUG_PAGEALLOC */
+#ifndef __HAVE_ARCH_CLEAR_PAGES

Also here, let's base it on

#ifndef clear_pages

and similarly below for clear_user_pages.

(sorry for the back-and-forth, it's rather unclear what the best practice is)

--
Cheers

David