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This feature is not available on all architectures yet, so ARCH_SUPPORTS_PT_RECLAIM is needed. We can remove it once all architectures support this feature. Signed-off-by: Qi Zheng --- mm/Kconfig | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/mm/Kconfig b/mm/Kconfig index 991fa9cf6137..7e2c87784d86 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -1256,6 +1256,20 @@ config IOMMU_MM_DATA config EXECMEM bool =20 +config ARCH_SUPPORTS_PT_RECLAIM + def_bool n + +config PT_RECLAIM + bool "reclaim empty user page table pages" + default y + depends on ARCH_SUPPORTS_PT_RECLAIM && MMU && SMP + select MMU_GATHER_RCU_TABLE_FREE + help + Try to reclaim empty user page table pages in paths other that munmap + and exit_mmap path. + + Note: now only empty user PTE page table pages will be reclaimed. + source "mm/damon/Kconfig" =20 endmenu --=20 2.20.1