Merge master.kernel.org:/pub/scm/linux/kernel/git/dtor/input

[pandora-kernel.git] / mm / Kconfig

diff --git a/mm/Kconfig b/mm/Kconfig
index 0320f06..cd37993 100644 (file)
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -1,9 +1,15 @@
+config SELECT_MEMORY_MODEL
+       def_bool y
+       depends on EXPERIMENTAL || ARCH_SELECT_MEMORY_MODEL
+
 choice
        prompt "Memory model"
-       default DISCONTIGMEM if ARCH_DISCONTIGMEM_DEFAULT
-       default FLATMEM
+       depends on SELECT_MEMORY_MODEL
+       default DISCONTIGMEM_MANUAL if ARCH_DISCONTIGMEM_DEFAULT
+       default SPARSEMEM_MANUAL if ARCH_SPARSEMEM_DEFAULT
+       default FLATMEM_MANUAL
 
-config FLATMEM
+config FLATMEM_MANUAL
        bool "Flat Memory"
        depends on !ARCH_DISCONTIGMEM_ENABLE || ARCH_FLATMEM_ENABLE
        help
@@ -12,16 +18,65 @@ config FLATMEM
          only have one option here: FLATMEM.  This is normal
          and a correct option.
 
-         If unsure, choose this option over any other.
+         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".
 
-config DISCONTIGMEM
+         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
@@ -30,3 +85,7 @@ endchoice
 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