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 <zhengqi.arch@xxxxxxxxxxxxx> --- 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
