[RFC PATCH 2/7] mm: introduce CONFIG_FREE_USER_PTE
From: Qi Zheng <hidden>
Date: 2022-08-25 10:11:55
Also in:
lkml
Subsystem:
memory management, memory management - core, the rest · Maintainers:
Andrew Morton, David Hildenbrand, Linus Torvalds
This configuration variable will be used to build the code needed to free user PTE page table pages. The PTE page table setting and clearing functions(such as set_pte_at()) are in the architecture's files, and these functions will be hooked to implement FREE_USER_PTE, so the architecture support is needed. Signed-off-by: Qi Zheng <redacted> --- mm/Kconfig | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/mm/Kconfig b/mm/Kconfig
index 169e64192e48..d2a5a24cee2d 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig@@ -1130,6 +1130,17 @@ config PTE_MARKER_UFFD_WP purposes. It is required to enable userfaultfd write protection on file-backed memory types like shmem and hugetlbfs. +config ARCH_SUPPORTS_FREE_USER_PTE + def_bool n + +config FREE_USER_PTE + bool "Free user PTE page table pages" + default y + depends on ARCH_SUPPORTS_FREE_USER_PTE && MMU && SMP + help + Try to free user PTE page table page when its all entries are none or + mapped shared zero page. + source "mm/damon/Kconfig" endmenu
--
2.20.1