diff --git a/mm/Kconfig b/mm/Kconfig index 9c61158308dc..527136b22384 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -171,6 +171,15 @@ config SPLIT_PTLOCK_CPUS default "999999" if DEBUG_SPINLOCK || DEBUG_LOCK_ALLOC default "4" +# +# support for memory compaction +config COMPACTION + bool "Allow for memory compaction" + select MIGRATION + depends on EXPERIMENTAL && HUGETLB_PAGE && MMU + help + Allows the compaction of memory for the allocation of huge pages. + # # support for page migration # @@ -180,9 +189,11 @@ config MIGRATION depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE help Allows the migration of the physical location of pages of processes - while the virtual addresses are not changed. This is useful for - example on NUMA systems to put pages nearer to the processors accessing - the page. + while the virtual addresses are not changed. This is useful in + two situations. The first is on NUMA systems to put pages nearer + to the processors accessing. The second is when allocating huge + pages as migration can relocate pages to satisfy a huge page + allocation instead of reclaiming. config PHYS_ADDR_T_64BIT def_bool 64BIT || ARCH_PHYS_ADDR_T_64BIT