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Dave Hansene1785e82005-06-23 00:07:49 -07001config SELECT_MEMORY_MODEL
2 def_bool y
3 depends on EXPERIMENTAL || ARCH_SELECT_MEMORY_MODEL
4
Dave Hansen3a9da762005-06-23 00:07:42 -07005choice
6 prompt "Memory model"
Dave Hansene1785e82005-06-23 00:07:49 -07007 depends on SELECT_MEMORY_MODEL
8 default DISCONTIGMEM_MANUAL if ARCH_DISCONTIGMEM_DEFAULT
Andy Whitcroftd41dee32005-06-23 00:07:54 -07009 default SPARSEMEM_MANUAL if ARCH_SPARSEMEM_DEFAULT
Dave Hansene1785e82005-06-23 00:07:49 -070010 default FLATMEM_MANUAL
Dave Hansen3a9da762005-06-23 00:07:42 -070011
Dave Hansene1785e82005-06-23 00:07:49 -070012config FLATMEM_MANUAL
Dave Hansen3a9da762005-06-23 00:07:42 -070013 bool "Flat Memory"
Anton Blanchardc898ec12006-01-06 00:12:07 -080014 depends on !(ARCH_DISCONTIGMEM_ENABLE || ARCH_SPARSEMEM_ENABLE) || ARCH_FLATMEM_ENABLE
Dave Hansen3a9da762005-06-23 00:07:42 -070015 help
16 This option allows you to change some of the ways that
17 Linux manages its memory internally. Most users will
18 only have one option here: FLATMEM. This is normal
19 and a correct option.
20
Andy Whitcroftd41dee32005-06-23 00:07:54 -070021 Some users of more advanced features like NUMA and
22 memory hotplug may have different options here.
23 DISCONTIGMEM is an more mature, better tested system,
24 but is incompatible with memory hotplug and may suffer
25 decreased performance over SPARSEMEM. If unsure between
26 "Sparse Memory" and "Discontiguous Memory", choose
27 "Discontiguous Memory".
28
29 If unsure, choose this option (Flat Memory) over any other.
Dave Hansen3a9da762005-06-23 00:07:42 -070030
Dave Hansene1785e82005-06-23 00:07:49 -070031config DISCONTIGMEM_MANUAL
Dave Hansenf3519f92005-09-16 19:27:54 -070032 bool "Discontiguous Memory"
Dave Hansen3a9da762005-06-23 00:07:42 -070033 depends on ARCH_DISCONTIGMEM_ENABLE
34 help
Dave Hansen785dcd42005-06-23 00:07:50 -070035 This option provides enhanced support for discontiguous
36 memory systems, over FLATMEM. These systems have holes
37 in their physical address spaces, and this option provides
38 more efficient handling of these holes. However, the vast
39 majority of hardware has quite flat address spaces, and
Philipp Marekad3d0a32007-10-20 02:46:58 +020040 can have degraded performance from the extra overhead that
Dave Hansen785dcd42005-06-23 00:07:50 -070041 this option imposes.
42
43 Many NUMA configurations will have this as the only option.
44
Dave Hansen3a9da762005-06-23 00:07:42 -070045 If unsure, choose "Flat Memory" over this option.
46
Andy Whitcroftd41dee32005-06-23 00:07:54 -070047config SPARSEMEM_MANUAL
48 bool "Sparse Memory"
49 depends on ARCH_SPARSEMEM_ENABLE
50 help
51 This will be the only option for some systems, including
52 memory hotplug systems. This is normal.
53
54 For many other systems, this will be an alternative to
Dave Hansenf3519f92005-09-16 19:27:54 -070055 "Discontiguous Memory". This option provides some potential
Andy Whitcroftd41dee32005-06-23 00:07:54 -070056 performance benefits, along with decreased code complexity,
57 but it is newer, and more experimental.
58
59 If unsure, choose "Discontiguous Memory" or "Flat Memory"
60 over this option.
61
Dave Hansen3a9da762005-06-23 00:07:42 -070062endchoice
63
Dave Hansene1785e82005-06-23 00:07:49 -070064config DISCONTIGMEM
65 def_bool y
66 depends on (!SELECT_MEMORY_MODEL && ARCH_DISCONTIGMEM_ENABLE) || DISCONTIGMEM_MANUAL
67
Andy Whitcroftd41dee32005-06-23 00:07:54 -070068config SPARSEMEM
69 def_bool y
70 depends on SPARSEMEM_MANUAL
71
Dave Hansene1785e82005-06-23 00:07:49 -070072config FLATMEM
73 def_bool y
Andy Whitcroftd41dee32005-06-23 00:07:54 -070074 depends on (!DISCONTIGMEM && !SPARSEMEM) || FLATMEM_MANUAL
75
76config FLAT_NODE_MEM_MAP
77 def_bool y
78 depends on !SPARSEMEM
Dave Hansene1785e82005-06-23 00:07:49 -070079
Nick Piggin8174c432008-07-25 19:45:24 -070080config HAVE_GET_USER_PAGES_FAST
81 bool
82
Dave Hansen93b75042005-06-23 00:07:47 -070083#
84# Both the NUMA code and DISCONTIGMEM use arrays of pg_data_t's
85# to represent different areas of memory. This variable allows
86# those dependencies to exist individually.
87#
88config NEED_MULTIPLE_NODES
89 def_bool y
90 depends on DISCONTIGMEM || NUMA
Andy Whitcroftaf705362005-06-23 00:07:53 -070091
92config HAVE_MEMORY_PRESENT
93 def_bool y
Andy Whitcroftd41dee32005-06-23 00:07:54 -070094 depends on ARCH_HAVE_MEMORY_PRESENT || SPARSEMEM
Bob Picco802f1922005-09-03 15:54:26 -070095
96#
Bob Picco3e347262005-09-03 15:54:28 -070097# SPARSEMEM_EXTREME (which is the default) does some bootmem
Matt LaPlante84eb8d02006-10-03 22:53:09 +020098# allocations when memory_present() is called. If this cannot
Bob Picco3e347262005-09-03 15:54:28 -070099# be done on your architecture, select this option. However,
100# statically allocating the mem_section[] array can potentially
101# consume vast quantities of .bss, so be careful.
102#
103# This option will also potentially produce smaller runtime code
104# with gcc 3.4 and later.
105#
106config SPARSEMEM_STATIC
107 def_bool n
108
109#
Matt LaPlante44c09202006-10-03 22:34:14 +0200110# Architecture platforms which require a two level mem_section in SPARSEMEM
Bob Picco802f1922005-09-03 15:54:26 -0700111# must select this option. This is usually for architecture platforms with
112# an extremely sparse physical address space.
113#
Bob Picco3e347262005-09-03 15:54:28 -0700114config SPARSEMEM_EXTREME
115 def_bool y
116 depends on SPARSEMEM && !SPARSEMEM_STATIC
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700117
Andy Whitcroft29c71112007-10-16 01:24:14 -0700118config SPARSEMEM_VMEMMAP_ENABLE
119 def_bool n
120
121config SPARSEMEM_VMEMMAP
Geoff Levanda5ee6da2007-12-17 16:19:53 -0800122 bool "Sparse Memory virtual memmap"
123 depends on SPARSEMEM && SPARSEMEM_VMEMMAP_ENABLE
124 default y
125 help
126 SPARSEMEM_VMEMMAP uses a virtually mapped memmap to optimise
127 pfn_to_page and page_to_pfn operations. This is the most
128 efficient option when sufficient kernel resources are available.
Andy Whitcroft29c71112007-10-16 01:24:14 -0700129
Dave Hansen3947be12005-10-29 18:16:54 -0700130# eventually, we can have this option just 'select SPARSEMEM'
131config MEMORY_HOTPLUG
132 bool "Allow for memory hot-add"
Keith Manntheyec69acb2006-09-30 23:27:05 -0700133 depends on SPARSEMEM || X86_64_ACPI_NUMA
Rafael J. Wysockib0cb1a12007-07-29 23:24:36 +0200134 depends on HOTPLUG && !HIBERNATION && ARCH_ENABLE_MEMORY_HOTPLUG
Heiko Carstens421c1752008-07-14 09:59:18 +0200135 depends on (IA64 || X86 || PPC64 || SUPERH || S390)
Dave Hansen3947be12005-10-29 18:16:54 -0700136
137comment "Memory hotplug is currently incompatible with Software Suspend"
Rafael J. Wysockib0cb1a12007-07-29 23:24:36 +0200138 depends on SPARSEMEM && HOTPLUG && HIBERNATION
Dave Hansen3947be12005-10-29 18:16:54 -0700139
Keith Manntheyec69acb2006-09-30 23:27:05 -0700140config MEMORY_HOTPLUG_SPARSE
141 def_bool y
142 depends on SPARSEMEM && MEMORY_HOTPLUG
143
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -0700144config MEMORY_HOTREMOVE
145 bool "Allow for memory hot remove"
146 depends on MEMORY_HOTPLUG && ARCH_ENABLE_MEMORY_HOTREMOVE
147 depends on MIGRATION
148
Christoph Lametere20b8cc2008-04-28 02:12:55 -0700149#
150# If we have space for more page flags then we can enable additional
151# optimizations and functionality.
152#
153# Regular Sparsemem takes page flag bits for the sectionid if it does not
154# use a virtual memmap. Disable extended page flags for 32 bit platforms
155# that require the use of a sectionid in the page flags.
156#
157config PAGEFLAGS_EXTENDED
158 def_bool y
159 depends on 64BIT || SPARSEMEM_VMEMMAP || !NUMA || !SPARSEMEM
160
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700161# Heavily threaded applications may benefit from splitting the mm-wide
162# page_table_lock, so that faults on different parts of the user address
163# space can be handled with less contention: split it at this NR_CPUS.
164# Default to 4 for wider testing, though 8 might be more appropriate.
165# ARM's adjust_pte (unused if VIPT) depends on mm-wide page_table_lock.
Hugh Dickins7b6ac9d2005-11-23 13:37:37 -0800166# PA-RISC 7xxx's spinlock_t would enlarge struct page from 32 to 44 bytes.
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700167#
168config SPLIT_PTLOCK_CPUS
169 int
170 default "4096" if ARM && !CPU_CACHE_VIPT
Hugh Dickins7b6ac9d2005-11-23 13:37:37 -0800171 default "4096" if PARISC && !PA20
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700172 default "4"
Christoph Lameter7cbe34c2006-01-08 01:00:49 -0800173
174#
175# support for page migration
176#
177config MIGRATION
Christoph Lameterb20a3502006-03-22 00:09:12 -0800178 bool "Page migration"
Christoph Lameter6c5240a2006-06-23 02:03:37 -0700179 def_bool y
Gerald Schaefer83d16742008-07-23 21:28:22 -0700180 depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE
Christoph Lameterb20a3502006-03-22 00:09:12 -0800181 help
182 Allows the migration of the physical location of pages of processes
183 while the virtual addresses are not changed. This is useful for
184 example on NUMA systems to put pages nearer to the processors accessing
185 the page.
Greg Kroah-Hartman6550e072006-06-12 17:11:31 -0700186
187config RESOURCES_64BIT
188 bool "64 bit Memory and IO resources (EXPERIMENTAL)" if (!64BIT && EXPERIMENTAL)
189 default 64BIT
190 help
191 This option allows memory and IO resources to be 64 bit.
Christoph Lameter4b51d662007-02-10 01:43:10 -0800192
193config ZONE_DMA_FLAG
194 int
195 default "0" if !ZONE_DMA
196 default "1"
197
Christoph Lameter2a7326b2007-07-17 04:03:37 -0700198config BOUNCE
199 def_bool y
200 depends on BLOCK && MMU && (ZONE_DMA || HIGHMEM)
201
Christoph Lameter6225e932007-05-06 14:49:50 -0700202config NR_QUICK
203 int
204 depends on QUICKLIST
Haavard Skinnemoen38510752008-01-14 23:35:32 +0100205 default "2" if SUPERH || AVR32
Christoph Lameter6225e932007-05-06 14:49:50 -0700206 default "1"
Stephen Rothwellf057eac2007-07-15 23:40:05 -0700207
208config VIRT_TO_BUS
209 def_bool y
210 depends on !ARCH_NO_VIRT_TO_BUS
Andrea Arcangelicddb8a52008-07-28 15:46:29 -0700211
212config MMU_NOTIFIER
213 bool