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Roman Zippel80daa562008-01-14 04:51:16 +01001config ARCH
2 string
3 option env="ARCH"
4
5config KERNELVERSION
6 string
7 option env="KERNELVERSION"
8
Roman Zippelface4372006-06-08 22:12:45 -07009config DEFCONFIG_LIST
10 string
Paolo 'Blaisorblade' Giarrussob2670ea2006-10-19 23:28:23 -070011 depends on !UML
Roman Zippelface4372006-06-08 22:12:45 -070012 option defconfig_list
13 default "/lib/modules/$UNAME_RELEASE/.config"
14 default "/etc/kernel-config"
15 default "/boot/config-$UNAME_RELEASE"
16 default "arch/$ARCH/defconfig"
17
Al Boldiff0cfc62007-07-31 00:39:23 -070018menu "General setup"
Linus Torvalds1da177e2005-04-16 15:20:36 -070019
20config EXPERIMENTAL
21 bool "Prompt for development and/or incomplete code/drivers"
22 ---help---
23 Some of the various things that Linux supports (such as network
24 drivers, file systems, network protocols, etc.) can be in a state
25 of development where the functionality, stability, or the level of
26 testing is not yet high enough for general use. This is usually
27 known as the "alpha-test" phase among developers. If a feature is
28 currently in alpha-test, then the developers usually discourage
29 uninformed widespread use of this feature by the general public to
30 avoid "Why doesn't this work?" type mail messages. However, active
31 testing and use of these systems is welcomed. Just be aware that it
32 may not meet the normal level of reliability or it may fail to work
33 in some special cases. Detailed bug reports from people familiar
34 with the kernel internals are usually welcomed by the developers
35 (before submitting bug reports, please read the documents
36 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
37 <file:Documentation/BUG-HUNTING>, and
38 <file:Documentation/oops-tracing.txt> in the kernel source).
39
40 This option will also make obsoleted drivers available. These are
41 drivers that have been replaced by something else, and/or are
42 scheduled to be removed in a future kernel release.
43
44 Unless you intend to help test and develop a feature or driver that
45 falls into this category, or you have a situation that requires
46 using these features, you should probably say N here, which will
47 cause the configurator to present you with fewer choices. If
48 you say Y here, you will be offered the choice of using features or
49 drivers that are currently considered to be in the alpha-test phase.
50
Linus Torvalds1da177e2005-04-16 15:20:36 -070051config BROKEN
52 bool
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
54config BROKEN_ON_SMP
55 bool
56 depends on BROKEN || !SMP
57 default y
58
59config LOCK_KERNEL
60 bool
61 depends on SMP || PREEMPT
62 default y
63
64config INIT_ENV_ARG_LIMIT
65 int
Adrian Bunkdd673bc2006-06-30 01:55:51 -070066 default 32 if !UML
67 default 128 if UML
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 help
Randy Dunlap34ad92c2005-10-30 15:01:46 -080069 Maximum of each of the number of arguments and environment
70 variables passed to init from the kernel command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -070071
Linus Torvalds1da177e2005-04-16 15:20:36 -070072
73config LOCALVERSION
74 string "Local version - append to kernel release"
75 help
76 Append an extra string to the end of your kernel version.
77 This will show up when you type uname, for example.
78 The string you set here will be appended after the contents of
79 any files with a filename matching localversion* in your
80 object and source tree, in that order. Your total string can
81 be a maximum of 64 characters.
82
Ryan Andersonaaebf432005-07-31 04:57:49 -040083config LOCALVERSION_AUTO
84 bool "Automatically append version information to the version string"
85 default y
86 help
87 This will try to automatically determine if the current tree is a
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020088 release tree by looking for git tags that belong to the current
89 top of tree revision.
Ryan Andersonaaebf432005-07-31 04:57:49 -040090
91 A string of the format -gxxxxxxxx will be added to the localversion
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020092 if a git-based tree is found. The string generated by this will be
Ryan Andersonaaebf432005-07-31 04:57:49 -040093 appended after any matching localversion* files, and after the value
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020094 set in CONFIG_LOCALVERSION.
Ryan Andersonaaebf432005-07-31 04:57:49 -040095
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020096 (The actual string used here is the first eight characters produced
97 by running the command:
98
99 $ git rev-parse --verify HEAD
100
101 which is done within the script "scripts/setlocalversion".)
Ryan Andersonaaebf432005-07-31 04:57:49 -0400102
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103config SWAP
104 bool "Support for paging of anonymous memory (swap)"
David Howells93614012006-09-30 20:45:40 +0200105 depends on MMU && BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106 default y
107 help
108 This option allows you to choose whether you want to have support
Jesper Juhl92c35042006-01-15 02:40:08 +0100109 for so called swap devices or swap files in your kernel that are
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 used to provide more virtual memory than the actual RAM present
111 in your computer. If unsure say Y.
112
113config SYSVIPC
114 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 ---help---
116 Inter Process Communication is a suite of library functions and
117 system calls which let processes (running programs) synchronize and
118 exchange information. It is generally considered to be a good thing,
119 and some programs won't run unless you say Y here. In particular, if
120 you want to run the DOS emulator dosemu under Linux (read the
121 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
122 you'll need to say Y here.
123
124 You can find documentation about IPC with "info ipc" and also in
125 section 6.4 of the Linux Programmer's Guide, available from
126 <http://www.tldp.org/guides.html>.
127
Eric W. Biedermana5494dc2007-02-14 00:34:06 -0800128config SYSVIPC_SYSCTL
129 bool
130 depends on SYSVIPC
131 depends on SYSCTL
132 default y
133
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134config POSIX_MQUEUE
135 bool "POSIX Message Queues"
136 depends on NET && EXPERIMENTAL
137 ---help---
138 POSIX variant of message queues is a part of IPC. In POSIX message
139 queues every message has a priority which decides about succession
140 of receiving it by a process. If you want to compile and run
141 programs written e.g. for Solaris with use of its POSIX message
Robert P. J. Dayb0e37652007-05-09 07:25:13 +0200142 queues (functions mq_*) say Y here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143
144 POSIX message queues are visible as a filesystem called 'mqueue'
145 and can be mounted somewhere if you want to do filesystem
146 operations on message queues.
147
148 If unsure, say Y.
149
150config BSD_PROCESS_ACCT
151 bool "BSD Process Accounting"
152 help
153 If you say Y here, a user level program will be able to instruct the
154 kernel (via a special system call) to write process accounting
155 information to a file: whenever a process exits, information about
156 that process will be appended to the file by the kernel. The
157 information includes things such as creation time, owning user,
158 command name, memory usage, controlling terminal etc. (the complete
159 list is in the struct acct in <file:include/linux/acct.h>). It is
160 up to the user level program to do useful things with this
161 information. This is generally a good idea, so say Y.
162
163config BSD_PROCESS_ACCT_V3
164 bool "BSD Process Accounting version 3 file format"
165 depends on BSD_PROCESS_ACCT
166 default n
167 help
168 If you say Y here, the process accounting information is written
169 in a new file format that also logs the process IDs of each
170 process and it's parent. Note that this file format is incompatible
171 with previous v0/v1/v2 file formats, so you will need updated tools
172 for processing it. A preliminary version of these tools is available
173 at <http://www.physik3.uni-rostock.de/tim/kernel/utils/acct/>.
174
Shailabh Nagarc7572492006-07-14 00:24:40 -0700175config TASKSTATS
176 bool "Export task/process statistics through netlink (EXPERIMENTAL)"
177 depends on NET
178 default n
179 help
180 Export selected statistics for tasks/processes through the
181 generic netlink interface. Unlike BSD process accounting, the
182 statistics are available during the lifetime of tasks/processes as
183 responses to commands. Like BSD accounting, they are sent to user
184 space on task exit.
185
186 Say N if unsure.
187
Shailabh Nagarca74e922006-07-14 00:24:36 -0700188config TASK_DELAY_ACCT
189 bool "Enable per-task delay accounting (EXPERIMENTAL)"
Shailabh Nagar6f449932006-07-14 00:24:41 -0700190 depends on TASKSTATS
Shailabh Nagarca74e922006-07-14 00:24:36 -0700191 help
192 Collect information on time spent by a task waiting for system
193 resources like cpu, synchronous block I/O completion and swapping
194 in pages. Such statistics can help in setting a task's priorities
195 relative to other tasks for cpu, io, rss limits etc.
196
197 Say N if unsure.
198
Alexey Dobriyan18f705f2007-02-10 01:46:44 -0800199config TASK_XACCT
200 bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
201 depends on TASKSTATS
202 help
203 Collect extended task accounting data and send the data
204 to userland for processing over the taskstats interface.
205
206 Say N if unsure.
207
208config TASK_IO_ACCOUNTING
209 bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
210 depends on TASK_XACCT
211 help
212 Collect information on the number of bytes of storage I/O which this
213 task has caused.
214
215 Say N if unsure.
216
Cedric Le Goateracce2922007-07-15 23:40:59 -0700217config USER_NS
218 bool "User Namespaces (EXPERIMENTAL)"
219 default n
220 depends on EXPERIMENTAL
221 help
222 Support user namespaces. This allows containers, i.e.
223 vservers, to use user namespaces to provide different
224 user info for different servers. If unsure, say N.
225
Eric W. Biederman57d5f662007-11-14 17:00:13 -0800226config PID_NS
227 bool "PID Namespaces (EXPERIMENTAL)"
228 default n
229 depends on EXPERIMENTAL
230 help
231 Suport process id namespaces. This allows having multiple
232 process with the same pid as long as they are in different
233 pid namespaces. This is a building block of containers.
234
235 Unless you want to work with an experimental feature
236 say N here.
237
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238config AUDIT
239 bool "Auditing support"
Chris Wright804a6a42005-05-11 10:52:45 +0100240 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 help
242 Enable auditing infrastructure that can be used with another
243 kernel subsystem, such as SELinux (which requires this for
244 logging of avc messages output). Does not do system-call
245 auditing without CONFIG_AUDITSYSCALL.
246
247config AUDITSYSCALL
248 bool "Enable system-call auditing support"
Yuichi Nakamura1322b9d2007-11-10 19:21:34 +0900249 depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64|| SUPERH)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 default y if SECURITY_SELINUX
251 help
252 Enable low-overhead system-call auditing infrastructure that
253 can be used independently or with another kernel subsystem,
Amy Griffisf368c07d2006-04-07 16:55:56 -0400254 such as SELinux. To use audit's filesystem watch feature, please
255 ensure that INOTIFY is configured.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256
Al Viro74c3cbe2007-07-22 08:04:18 -0400257config AUDIT_TREE
258 def_bool y
259 depends on AUDITSYSCALL && INOTIFY
260
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700262 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263 ---help---
264 This option enables the complete Linux kernel ".config" file
265 contents to be saved in the kernel. It provides documentation
266 of which kernel options are used in a running kernel or in an
267 on-disk kernel. This information can be extracted from the kernel
268 image file with the script scripts/extract-ikconfig and used as
269 input to rebuild the current kernel or to build another kernel.
270 It can also be extracted from a running kernel by reading
271 /proc/config.gz if enabled (below).
272
273config IKCONFIG_PROC
274 bool "Enable access to .config through /proc/config.gz"
275 depends on IKCONFIG && PROC_FS
276 ---help---
277 This option enables access to the kernel configuration file
278 through /proc/config.gz.
279
Alistair John Strachan794543a2007-05-08 00:31:15 -0700280config LOG_BUF_SHIFT
281 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
282 range 12 21
283 default 17 if S390 || LOCKDEP
284 default 16 if X86_NUMAQ || IA64
285 default 15 if SMP
286 default 14
287 help
288 Select kernel log buffer size as a power of 2.
289 Defaults and Examples:
290 17 => 128 KB for S/390
291 16 => 64 KB for x86 NUMAQ or IA-64
292 15 => 32 KB for SMP
293 14 => 16 KB for uniprocessor
294 13 => 8 KB
295 12 => 4 KB
296
Paul Menageddbcc7e2007-10-18 23:39:30 -0700297config CGROUPS
298 bool "Control Group support"
299 help
300 This option will let you use process cgroup subsystems
301 such as Cpusets
302
303 Say N if unsure.
304
Paul Menage006cb992007-10-18 23:39:43 -0700305config CGROUP_DEBUG
306 bool "Example debug cgroup subsystem"
307 depends on CGROUPS
308 help
309 This option enables a simple cgroup subsystem that
310 exports useful debugging information about the cgroups
311 framework
312
313 Say N if unsure
314
Serge E. Hallyn858d72e2007-10-18 23:39:45 -0700315config CGROUP_NS
316 bool "Namespace cgroup subsystem"
317 depends on CGROUPS
318 help
319 Provides a simple namespace cgroup subsystem to
320 provide hierarchical naming of sets of namespaces,
321 for instance virtual servers and checkpoint/restart
322 jobs.
323
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324config CPUSETS
325 bool "Cpuset support"
Paul Menage8793d852007-10-18 23:39:39 -0700326 depends on SMP && CGROUPS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700328 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329 allow dynamically partitioning a system into sets of CPUs and
330 Memory Nodes and assigning tasks to run only within those sets.
331 This is primarily useful on large SMP or NUMA systems.
332
333 Say N if unsure.
334
Srivatsa Vaddagiri29f59db2007-10-15 17:00:07 +0200335config FAIR_GROUP_SCHED
Srivatsa Vaddagirifb615582007-10-15 17:00:12 +0200336 bool "Fair group CPU scheduler"
Ingo Molnarde8d5852007-10-15 17:00:09 +0200337 default y
Srivatsa Vaddagiri29f59db2007-10-15 17:00:07 +0200338 help
Srivatsa Vaddagirifb615582007-10-15 17:00:12 +0200339 This feature lets CPU scheduler recognize task groups and control CPU
Srivatsa Vaddagiri9b5b7752007-10-15 17:00:09 +0200340 bandwidth allocation to such task groups.
Srivatsa Vaddagiri29f59db2007-10-15 17:00:07 +0200341
Srivatsa Vaddagiri24e377a2007-10-15 17:00:09 +0200342choice
343 depends on FAIR_GROUP_SCHED
344 prompt "Basis for grouping tasks"
345 default FAIR_USER_SCHED
346
Srivatsa Vaddagirifb615582007-10-15 17:00:12 +0200347config FAIR_USER_SCHED
348 bool "user id"
349 help
350 This option will choose userid as the basis for grouping
351 tasks, thus providing equal CPU bandwidth to each user.
Srivatsa Vaddagiri24e377a2007-10-15 17:00:09 +0200352
Srivatsa Vaddagiri68318b82007-10-18 23:41:03 -0700353config FAIR_CGROUP_SCHED
354 bool "Control groups"
355 depends on CGROUPS
356 help
357 This option allows you to create arbitrary task groups
358 using the "cgroup" pseudo filesystem and control
359 the cpu bandwidth allocated to each such task group.
360 Refer to Documentation/cgroups.txt for more information
361 on "cgroup" pseudo filesystem.
362
Srivatsa Vaddagiri24e377a2007-10-15 17:00:09 +0200363endchoice
364
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100365config CGROUP_CPUACCT
366 bool "Simple CPU accounting cgroup subsystem"
367 depends on CGROUPS
368 help
369 Provides a simple Resource Controller for monitoring the
370 total CPU consumed by the tasks in a cgroup
371
Pavel Emelianove552b662008-02-07 00:13:49 -0800372config RESOURCE_COUNTERS
373 bool "Resource counters"
374 help
375 This option enables controller independent resource accounting
376 infrastructure that works with cgroups
377 depends on CGROUPS
378
Kay Sievers88a22c92006-09-14 11:23:28 +0200379config SYSFS_DEPRECATED
380 bool "Create deprecated sysfs files"
Randy Dunlap9148fe82007-12-31 10:05:34 -0800381 depends on SYSFS
Kay Sievers88a22c92006-09-14 11:23:28 +0200382 default y
383 help
384 This option creates deprecated symlinks such as the
385 "device"-link, the <subsystem>:<name>-link, and the
386 "bus"-link. It may also add deprecated key in the
387 uevent environment.
388 None of these features or values should be used today, as
389 they export driver core implementation details to userspace
390 or export properties which can't be kept stable across kernel
391 releases.
392
393 If enabled, this option will also move any device structures
David Sterba3dde6ad2007-05-09 07:12:20 +0200394 that belong to a class, back into the /sys/class hierarchy, in
Kay Sievers88a22c92006-09-14 11:23:28 +0200395 order to support older versions of udev.
396
397 If you are using a distro that was released in 2006 or later,
398 it should be safe to say N here.
399
Paul Menage8793d852007-10-18 23:39:39 -0700400config PROC_PID_CPUSET
401 bool "Include legacy /proc/<pid>/cpuset file"
402 depends on CPUSETS
403 default y
404
Jens Axboeb86ff982006-03-23 19:56:55 +0100405config RELAY
406 bool "Kernel->user space relay support (formerly relayfs)"
407 help
408 This option enables support for relay interface support in
409 certain file systems (such as debugfs).
410 It is designed to provide an efficient mechanism for tools and
411 facilities to relay large amounts of data from kernel space to
412 user space.
413
414 If unsure, say N.
415
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -0800416config BLK_DEV_INITRD
417 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
418 depends on BROKEN || !FRV
419 help
420 The initial RAM filesystem is a ramfs which is loaded by the
421 boot loader (loadlin or lilo) and that is mounted as root
422 before the normal boot procedure. It is typically used to
423 load modules needed to mount the "real" root file system,
424 etc. See <file:Documentation/initrd.txt> for details.
425
426 If RAM disk support (BLK_DEV_RAM) is also included, this
427 also enables initial RAM disk (initrd) support and adds
428 15 Kbytes (more on some other architectures) to the kernel size.
429
430 If unsure say Y.
431
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800432if BLK_DEV_INITRD
433
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200434source "usr/Kconfig"
435
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800436endif
437
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800438config CC_OPTIMIZE_FOR_SIZE
439 bool "Optimize for size (Look out for broken compilers!)"
440 default y
Paul Mundt32582fa2007-07-25 11:27:05 +0900441 depends on ARM || H8300 || SUPERH || EXPERIMENTAL
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800442 help
443 Enabling this option will pass "-Os" instead of "-O2" to gcc
444 resulting in a smaller kernel.
445
446 WARNING: some versions of gcc may generate incorrect code with this
447 option. If problems are observed, a gcc upgrade may be needed.
448
449 If unsure, say N.
450
Randy Dunlap08470622006-09-30 23:28:13 -0700451config SYSCTL
452 bool
453
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454menuconfig EMBEDDED
455 bool "Configure standard kernel features (for small systems)"
456 help
457 This option allows certain base kernel options and settings
458 to be disabled or tweaked. This is for specialized
459 environments which can tolerate a "non-standard" kernel.
460 Only use this if you really know what you are doing.
461
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700462config UID16
463 bool "Enable 16-bit UID system calls" if EMBEDDED
Mike Frysinger529a73f2007-11-23 14:28:44 +0800464 depends on ARM || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && SPARC32_COMPAT) || UML || (X86_64 && IA32_EMULATION)
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700465 default y
466 help
467 This enables the legacy 16-bit UID syscall wrappers.
468
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700469config SYSCTL_SYSCALL
Randy Dunlap08470622006-09-30 23:28:13 -0700470 bool "Sysctl syscall support" if EMBEDDED
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800471 default y
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700472 select SYSCTL
473 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800474 sys_sysctl uses binary paths that have been found challenging
475 to properly maintain and use. The interface in /proc/sys
476 using paths with ascii names is now the primary path to this
477 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700478
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800479 Almost nothing using the binary sysctl interface so if you are
480 trying to save some space it is probably safe to disable this,
481 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700482
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800483 If unsure say Y here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700484
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485config KALLSYMS
Jesper Juhl979c6a12006-12-12 19:25:11 +0100486 bool "Load all symbols for debugging/ksymoops" if EMBEDDED
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487 default y
488 help
489 Say Y here to let the kernel print out symbolic crash information and
490 symbolic stack backtraces. This increases the size of the kernel
491 somewhat, as all symbols have to be loaded into the kernel image.
492
493config KALLSYMS_ALL
494 bool "Include all symbols in kallsyms"
495 depends on DEBUG_KERNEL && KALLSYMS
496 help
497 Normally kallsyms only contains the symbols of functions, for nicer
498 OOPS messages. Some debuggers can use kallsyms for other
Jesper Juhlf9f97bc2005-07-20 05:43:05 +0200499 symbols too: say Y here to include all symbols, if you need them
500 and you don't care about adding 300k to the size of your kernel.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501
502 Say N.
503
504config KALLSYMS_EXTRA_PASS
505 bool "Do an extra kallsyms pass"
506 depends on KALLSYMS
507 help
508 If kallsyms is not working correctly, the build will fail with
509 inconsistent kallsyms data. If that occurs, log a bug report and
510 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
511 Always say N here unless you find a bug in kallsyms, which must be
512 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
513 you wait for kallsyms to be fixed.
514
Matt Mackalld59745c2005-05-01 08:59:02 -0700515
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -0800516config HOTPLUG
517 bool "Support for hot-pluggable devices" if EMBEDDED
518 default y
519 help
520 This option is provided for the case where no hotplug or uevent
521 capabilities is wanted by the kernel. You should only consider
522 disabling this option for embedded systems that do not use modules, a
523 dynamic /dev tree, or dynamic device discovery. Just say Y.
524
Matt Mackalld59745c2005-05-01 08:59:02 -0700525config PRINTK
526 default y
527 bool "Enable support for printk" if EMBEDDED
528 help
529 This option enables normal printk support. Removing it
530 eliminates most of the message strings from the kernel image
531 and makes the kernel more or less silent. As this makes it
532 very difficult to diagnose system problems, saying N here is
533 strongly discouraged.
534
Matt Mackallc8538a72005-05-01 08:59:01 -0700535config BUG
536 bool "BUG() support" if EMBEDDED
537 default y
538 help
539 Disabling this option eliminates support for BUG and WARN, reducing
540 the size of your kernel image and potentially quietly ignoring
541 numerous fatal conditions. You should only consider disabling this
542 option for embedded systems with no facilities for reporting errors.
543 Just say Y.
544
Matt Mackall708e9a72006-01-08 01:05:25 -0800545config ELF_CORE
546 default y
547 bool "Enable ELF core dumps" if EMBEDDED
548 help
549 Enable support for generating core dumps. Disabling saves about 4k.
550
Ingo Molnar32a93232008-02-06 22:39:44 +0100551config COMPAT_BRK
552 bool "Disable heap randomization"
553 default y
554 help
555 Randomizing heap placement makes heap exploits harder, but it
556 also breaks ancient binaries (including anything libc5 based).
557 This option changes the bootup default to heap randomization
558 disabled, and can be overriden runtime by setting
559 /proc/sys/kernel/randomize_va_space to 2.
560
561 On non-ancient distros (post-2000 ones) Y is usually a safe choice.
562
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563config BASE_FULL
564 default y
565 bool "Enable full-sized data structures for core" if EMBEDDED
566 help
567 Disabling this option reduces the size of miscellaneous core
568 kernel data structures. This saves memory on small machines,
569 but may reduce performance.
570
571config FUTEX
572 bool "Enable futex support" if EMBEDDED
573 default y
Ingo Molnar23f78d42006-06-27 02:54:53 -0700574 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575 help
576 Disabling this option will cause the kernel to be built without
577 support for "fast userspace mutexes". The resulting kernel may not
578 run glibc-based applications correctly.
579
Davide Libenzi5dc8bf82007-05-10 22:23:11 -0700580config ANON_INODES
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700581 bool
Davide Libenzi5dc8bf82007-05-10 22:23:11 -0700582
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583config EPOLL
584 bool "Enable eventpoll support" if EMBEDDED
585 default y
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700586 select ANON_INODES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587 help
588 Disabling this option will cause the kernel to be built without
589 support for epoll family of system calls.
590
Davide Libenzifba2afa2007-05-10 22:23:13 -0700591config SIGNALFD
592 bool "Enable signalfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700593 select ANON_INODES
Davide Libenzifba2afa2007-05-10 22:23:13 -0700594 default y
595 help
596 Enable the signalfd() system call that allows to receive signals
597 on a file descriptor.
598
599 If unsure, say Y.
600
Davide Libenzib215e282007-05-10 22:23:16 -0700601config TIMERFD
602 bool "Enable timerfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700603 select ANON_INODES
Davide Libenzib215e282007-05-10 22:23:16 -0700604 default y
605 help
606 Enable the timerfd() system call that allows to receive timer
607 events on a file descriptor.
608
609 If unsure, say Y.
610
Davide Libenzie1ad7462007-05-10 22:23:19 -0700611config EVENTFD
612 bool "Enable eventfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700613 select ANON_INODES
Davide Libenzie1ad7462007-05-10 22:23:19 -0700614 default y
615 help
616 Enable the eventfd() system call that allows to receive both
617 kernel notification (ie. KAIO) or userspace notifications.
618
619 If unsure, say Y.
620
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621config SHMEM
622 bool "Use full shmem filesystem" if EMBEDDED
623 default y
624 depends on MMU
625 help
626 The shmem is an internal filesystem used to manage shared memory.
627 It is backed by swap and manages resource limits. It is also exported
628 to userspace as tmpfs if TMPFS is enabled. Disabling this
629 option replaces shmem and tmpfs with the much simpler ramfs code,
630 which may be appropriate on small systems without swap.
631
Christoph Lameterf8891e52006-06-30 01:55:45 -0700632config VM_EVENT_COUNTERS
633 default y
634 bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
635 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -0800636 VM event counters are needed for event counts to be shown.
637 This option allows the disabling of the VM event counters
638 on EMBEDDED systems. /proc/vmstat will only show page counts
639 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -0700640
Christoph Lameter41ecc552007-05-09 02:32:44 -0700641config SLUB_DEBUG
642 default y
643 bool "Enable SLUB debugging support" if EMBEDDED
Christoph Lameterd4751a22007-05-10 03:15:40 -0700644 depends on SLUB
Christoph Lameter41ecc552007-05-09 02:32:44 -0700645 help
646 SLUB has extensive debug support features. Disabling these can
647 result in significant savings in code size. This also disables
648 SLUB sysfs support. /sys/slab will not exist and there will be
649 no support for cache validation etc.
650
Christoph Lameter81819f02007-05-06 14:49:36 -0700651choice
652 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -0700653 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -0700654 help
655 This option allows to select a slab allocator.
656
657config SLAB
658 bool "SLAB"
659 help
660 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -0700661 well in all environments. It organizes cache hot objects in
Christoph Lameter81819f02007-05-06 14:49:36 -0700662 per cpu and per node queues. SLAB is the default choice for
Christoph Lameter34013882007-05-09 02:32:47 -0700663 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -0700664
665config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -0700666 bool "SLUB (Unqueued Allocator)"
667 help
668 SLUB is a slab allocator that minimizes cache line usage
669 instead of managing queues of cached objects (SLAB approach).
670 Per cpu caching is realized using slabs of objects instead
671 of queues of objects. SLUB can use memory efficiently
Christoph Lameter34013882007-05-09 02:32:47 -0700672 and has enhanced diagnostics.
Christoph Lameter81819f02007-05-06 14:49:36 -0700673
674config SLOB
Paul Mundt84a01c22007-07-15 23:38:24 -0700675 depends on EMBEDDED
Christoph Lameter81819f02007-05-06 14:49:36 -0700676 bool "SLOB (Simple Allocator)"
677 help
Matt Mackall37291452008-02-04 22:29:38 -0800678 SLOB replaces the stock allocator with a drastically simpler
679 allocator. SLOB is generally more space efficient but
680 does not perform as well on large systems.
Christoph Lameter81819f02007-05-06 14:49:36 -0700681
682endchoice
683
Mathieu Desnoyers125e5642008-02-02 15:10:36 -0500684config PROFILING
685 bool "Profiling support (EXPERIMENTAL)"
686 help
687 Say Y here to enable the extended profiling support mechanisms used
688 by profilers such as OProfile.
689
690config MARKERS
691 bool "Activate markers"
692 help
693 Place an empty function call at each marker site. Can be
694 dynamically changed for a probe function.
695
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -0500696source "arch/Kconfig"
697
Matt Mackall1e883282008-02-04 22:29:07 -0800698config PROC_PAGE_MONITOR
699 default y
700 depends on PROC_FS && MMU
701 bool "Enable /proc page monitoring" if EMBEDDED
702 help
703 Various /proc files exist to monitor process memory utilization:
704 /proc/pid/smaps, /proc/pid/clear_refs, /proc/pid/pagemap,
705 /proc/kpagecount, and /proc/kpageflags. Disabling these
706 interfaces will reduce the size of the kernel by approximately 4kb.
707
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708endmenu # General setup
709
Linus Torvalds158a9622008-01-02 13:04:48 -0800710config SLABINFO
711 bool
712 depends on PROC_FS
713 depends on SLAB || SLUB
714 default y
715
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700716config RT_MUTEXES
717 boolean
718 select PLIST
719
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720config TINY_SHMEM
721 default !SHMEM
722 bool
723
724config BASE_SMALL
725 int
726 default 0 if BASE_FULL
727 default 1 if !BASE_FULL
728
Jan Engelhardt66da5732007-07-15 23:39:29 -0700729menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730 bool "Enable loadable module support"
731 help
732 Kernel modules are small pieces of compiled code which can
733 be inserted in the running kernel, rather than being
734 permanently built into the kernel. You use the "modprobe"
735 tool to add (and sometimes remove) them. If you say Y here,
736 many parts of the kernel can be built as modules (by
737 answering M instead of Y where indicated): this is most
738 useful for infrequently used options which are not required
739 for booting. For more information, see the man pages for
740 modprobe, lsmod, modinfo, insmod and rmmod.
741
742 If you say Y here, you will need to run "make
743 modules_install" to put the modules under /lib/modules/
744 where modprobe can find them (you may need to be root to do
745 this).
746
747 If unsure, say Y.
748
749config MODULE_UNLOAD
750 bool "Module unloading"
751 depends on MODULES
752 help
753 Without this option you will not be able to unload any
754 modules (note that some modules may not be unloadable
755 anyway), which makes your kernel slightly smaller and
756 simpler. If unsure, say Y.
757
758config MODULE_FORCE_UNLOAD
759 bool "Forced module unloading"
760 depends on MODULE_UNLOAD && EXPERIMENTAL
761 help
762 This option allows you to force a module to unload, even if the
763 kernel believes it is unsafe: the kernel will remove the module
764 without waiting for anyone to stop using it (using the -f option to
765 rmmod). This is mainly for kernel developers and desperate users.
766 If unsure, say N.
767
Linus Torvalds1da177e2005-04-16 15:20:36 -0700768config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +0100769 bool "Module versioning support"
770 depends on MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771 help
772 Usually, you have to use modules compiled with your kernel.
773 Saying Y here makes it sometimes possible to use modules
774 compiled for different kernels, by adding enough information
775 to the modules to (hopefully) spot any changes which would
776 make them incompatible with the kernel you are running. If
777 unsure, say N.
778
779config MODULE_SRCVERSION_ALL
780 bool "Source checksum for all modules"
781 depends on MODULES
782 help
783 Modules which contain a MODULE_VERSION get an extra "srcversion"
784 field inserted into their modinfo section, which contains a
785 sum of the source files which made it. This helps maintainers
786 see exactly which source was used to build a module (since
787 others sometimes change the module source without updating
788 the version). With this option, such a "srcversion" field
789 will be created for all modules. If unsure, say N.
790
791config KMOD
792 bool "Automatic kernel module loading"
793 depends on MODULES
794 help
795 Normally when you have selected some parts of the kernel to
796 be created as kernel modules, you must load them (using the
797 "modprobe" command) before you can use them. If you say Y
798 here, some parts of the kernel will be able to load modules
799 automatically: when a part of the kernel needs a module, it
800 runs modprobe with the appropriate arguments, thereby
801 loading the module if it is available. If unsure, say Y.
802
803config STOP_MACHINE
804 bool
805 default y
806 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
807 help
808 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +0100809
Jens Axboe3a65dfe2005-11-04 08:43:35 +0100810source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -0700811
812config PREEMPT_NOTIFIERS
813 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +0100814
815choice
816 prompt "RCU implementation type:"
817 default CLASSIC_RCU
Paul E. McKenney09503102008-01-31 22:45:22 +0100818 help
819 This allows you to choose either the classic RCU implementation
820 that is designed for best read-side performance on non-realtime
821 systems, or the preemptible RCU implementation for best latency
822 on realtime systems. Note that some kernel preemption modes
823 will restrict your choice.
824
825 Select the default if you are unsure.
Paul E. McKenneye260be62008-01-25 21:08:24 +0100826
827config CLASSIC_RCU
828 bool "Classic RCU"
829 help
830 This option selects the classic RCU implementation that is
831 designed for best read-side performance on non-realtime
832 systems.
833
834 Say Y if you are unsure.
835
836config PREEMPT_RCU
837 bool "Preemptible RCU"
838 depends on PREEMPT
839 help
840 This option reduces the latency of the kernel by making certain
841 RCU sections preemptible. Normally RCU code is non-preemptible, if
842 this option is selected then read-only RCU sections become
843 preemptible. This helps latency, but may expose bugs due to
844 now-naive assumptions about each RCU read-side critical section
845 remaining on a given CPU through its execution.
846
847 Say N if you are unsure.
848
849endchoice