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Diffstat (limited to 'mm/Kconfig')
| -rw-r--r-- | mm/Kconfig | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/mm/Kconfig b/mm/Kconfig new file mode 100644 index 000000000000..cd379936cac6 --- /dev/null +++ b/mm/Kconfig @@ -0,0 +1,91 @@ +config SELECT_MEMORY_MODEL + def_bool y + depends on EXPERIMENTAL || ARCH_SELECT_MEMORY_MODEL + +choice + prompt "Memory model" + depends on SELECT_MEMORY_MODEL + default DISCONTIGMEM_MANUAL if ARCH_DISCONTIGMEM_DEFAULT + default SPARSEMEM_MANUAL if ARCH_SPARSEMEM_DEFAULT + default FLATMEM_MANUAL + +config FLATMEM_MANUAL + bool "Flat Memory" + depends on !ARCH_DISCONTIGMEM_ENABLE || ARCH_FLATMEM_ENABLE + help + This option allows you to change some of the ways that + Linux manages its memory internally. Most users will + only have one option here: FLATMEM. This is normal + and a correct option. + + Some users of more advanced features like NUMA and + memory hotplug may have different options here. + DISCONTIGMEM is an more mature, better tested system, + but is incompatible with memory hotplug and may suffer + decreased performance over SPARSEMEM. If unsure between + "Sparse Memory" and "Discontiguous Memory", choose + "Discontiguous Memory". + + If unsure, choose this option (Flat Memory) over any other. + +config DISCONTIGMEM_MANUAL + bool "Discontigious Memory" + depends on ARCH_DISCONTIGMEM_ENABLE + help + This option provides enhanced support for discontiguous + memory systems, over FLATMEM. These systems have holes + in their physical address spaces, and this option provides + more efficient handling of these holes. However, the vast + majority of hardware has quite flat address spaces, and + can have degraded performance from extra overhead that + this option imposes. + + Many NUMA configurations will have this as the only option. + + If unsure, choose "Flat Memory" over this option. + +config SPARSEMEM_MANUAL + bool "Sparse Memory" + depends on ARCH_SPARSEMEM_ENABLE + help + This will be the only option for some systems, including + memory hotplug systems. This is normal. + + For many other systems, this will be an alternative to + "Discontigious Memory". This option provides some potential + performance benefits, along with decreased code complexity, + but it is newer, and more experimental. + + If unsure, choose "Discontiguous Memory" or "Flat Memory" + over this option. + +endchoice + +config DISCONTIGMEM + def_bool y + depends on (!SELECT_MEMORY_MODEL && ARCH_DISCONTIGMEM_ENABLE) || DISCONTIGMEM_MANUAL + +config SPARSEMEM + def_bool y + depends on SPARSEMEM_MANUAL + +config FLATMEM + def_bool y + depends on (!DISCONTIGMEM && !SPARSEMEM) || FLATMEM_MANUAL + +config FLAT_NODE_MEM_MAP + def_bool y + depends on !SPARSEMEM + +# +# Both the NUMA code and DISCONTIGMEM use arrays of pg_data_t's +# to represent different areas of memory. This variable allows +# those dependencies to exist individually. +# +config NEED_MULTIPLE_NODES + def_bool y + depends on DISCONTIGMEM || NUMA + +config HAVE_MEMORY_PRESENT + def_bool y + depends on ARCH_HAVE_MEMORY_PRESENT || SPARSEMEM |