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Roman Zippelface4372006-06-08 22:12:45 -07001config DEFCONFIG_LIST
2 string
Paolo 'Blaisorblade' Giarrussob2670eac2006-10-19 23:28:23 -07003 depends on !UML
Roman Zippelface4372006-06-08 22:12:45 -07004 option defconfig_list
5 default "/lib/modules/$UNAME_RELEASE/.config"
6 default "/etc/kernel-config"
7 default "/boot/config-$UNAME_RELEASE"
8 default "arch/$ARCH/defconfig"
9
Al Boldiff0cfc62007-07-31 00:39:23 -070010menu "General setup"
Linus Torvalds1da177e2005-04-16 15:20:36 -070011
12config EXPERIMENTAL
13 bool "Prompt for development and/or incomplete code/drivers"
14 ---help---
15 Some of the various things that Linux supports (such as network
16 drivers, file systems, network protocols, etc.) can be in a state
17 of development where the functionality, stability, or the level of
18 testing is not yet high enough for general use. This is usually
19 known as the "alpha-test" phase among developers. If a feature is
20 currently in alpha-test, then the developers usually discourage
21 uninformed widespread use of this feature by the general public to
22 avoid "Why doesn't this work?" type mail messages. However, active
23 testing and use of these systems is welcomed. Just be aware that it
24 may not meet the normal level of reliability or it may fail to work
25 in some special cases. Detailed bug reports from people familiar
26 with the kernel internals are usually welcomed by the developers
27 (before submitting bug reports, please read the documents
28 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
29 <file:Documentation/BUG-HUNTING>, and
30 <file:Documentation/oops-tracing.txt> in the kernel source).
31
32 This option will also make obsoleted drivers available. These are
33 drivers that have been replaced by something else, and/or are
34 scheduled to be removed in a future kernel release.
35
36 Unless you intend to help test and develop a feature or driver that
37 falls into this category, or you have a situation that requires
38 using these features, you should probably say N here, which will
39 cause the configurator to present you with fewer choices. If
40 you say Y here, you will be offered the choice of using features or
41 drivers that are currently considered to be in the alpha-test phase.
42
Linus Torvalds1da177e2005-04-16 15:20:36 -070043config BROKEN
44 bool
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
46config BROKEN_ON_SMP
47 bool
48 depends on BROKEN || !SMP
49 default y
50
51config LOCK_KERNEL
52 bool
53 depends on SMP || PREEMPT
54 default y
55
56config INIT_ENV_ARG_LIMIT
57 int
Adrian Bunkdd673bc2006-06-30 01:55:51 -070058 default 32 if !UML
59 default 128 if UML
Linus Torvalds1da177e2005-04-16 15:20:36 -070060 help
Randy Dunlap34ad92c2005-10-30 15:01:46 -080061 Maximum of each of the number of arguments and environment
62 variables passed to init from the kernel command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
65config LOCALVERSION
66 string "Local version - append to kernel release"
67 help
68 Append an extra string to the end of your kernel version.
69 This will show up when you type uname, for example.
70 The string you set here will be appended after the contents of
71 any files with a filename matching localversion* in your
72 object and source tree, in that order. Your total string can
73 be a maximum of 64 characters.
74
Ryan Andersonaaebf432005-07-31 04:57:49 -040075config LOCALVERSION_AUTO
76 bool "Automatically append version information to the version string"
77 default y
78 help
79 This will try to automatically determine if the current tree is a
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020080 release tree by looking for git tags that belong to the current
81 top of tree revision.
Ryan Andersonaaebf432005-07-31 04:57:49 -040082
83 A string of the format -gxxxxxxxx will be added to the localversion
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020084 if a git-based tree is found. The string generated by this will be
Ryan Andersonaaebf432005-07-31 04:57:49 -040085 appended after any matching localversion* files, and after the value
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020086 set in CONFIG_LOCALVERSION.
Ryan Andersonaaebf432005-07-31 04:57:49 -040087
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020088 (The actual string used here is the first eight characters produced
89 by running the command:
90
91 $ git rev-parse --verify HEAD
92
93 which is done within the script "scripts/setlocalversion".)
Ryan Andersonaaebf432005-07-31 04:57:49 -040094
Linus Torvalds1da177e2005-04-16 15:20:36 -070095config SWAP
96 bool "Support for paging of anonymous memory (swap)"
David Howells93614012006-09-30 20:45:40 +020097 depends on MMU && BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -070098 default y
99 help
100 This option allows you to choose whether you want to have support
Jesper Juhl92c35042006-01-15 02:40:08 +0100101 for so called swap devices or swap files in your kernel that are
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 used to provide more virtual memory than the actual RAM present
103 in your computer. If unsure say Y.
104
105config SYSVIPC
106 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 ---help---
108 Inter Process Communication is a suite of library functions and
109 system calls which let processes (running programs) synchronize and
110 exchange information. It is generally considered to be a good thing,
111 and some programs won't run unless you say Y here. In particular, if
112 you want to run the DOS emulator dosemu under Linux (read the
113 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
114 you'll need to say Y here.
115
116 You can find documentation about IPC with "info ipc" and also in
117 section 6.4 of the Linux Programmer's Guide, available from
118 <http://www.tldp.org/guides.html>.
119
Eric W. Biedermana5494dc2007-02-14 00:34:06 -0800120config SYSVIPC_SYSCTL
121 bool
122 depends on SYSVIPC
123 depends on SYSCTL
124 default y
125
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126config POSIX_MQUEUE
127 bool "POSIX Message Queues"
128 depends on NET && EXPERIMENTAL
129 ---help---
130 POSIX variant of message queues is a part of IPC. In POSIX message
131 queues every message has a priority which decides about succession
132 of receiving it by a process. If you want to compile and run
133 programs written e.g. for Solaris with use of its POSIX message
Robert P. J. Dayb0e37652007-05-09 07:25:13 +0200134 queues (functions mq_*) say Y here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135
136 POSIX message queues are visible as a filesystem called 'mqueue'
137 and can be mounted somewhere if you want to do filesystem
138 operations on message queues.
139
140 If unsure, say Y.
141
142config BSD_PROCESS_ACCT
143 bool "BSD Process Accounting"
144 help
145 If you say Y here, a user level program will be able to instruct the
146 kernel (via a special system call) to write process accounting
147 information to a file: whenever a process exits, information about
148 that process will be appended to the file by the kernel. The
149 information includes things such as creation time, owning user,
150 command name, memory usage, controlling terminal etc. (the complete
151 list is in the struct acct in <file:include/linux/acct.h>). It is
152 up to the user level program to do useful things with this
153 information. This is generally a good idea, so say Y.
154
155config BSD_PROCESS_ACCT_V3
156 bool "BSD Process Accounting version 3 file format"
157 depends on BSD_PROCESS_ACCT
158 default n
159 help
160 If you say Y here, the process accounting information is written
161 in a new file format that also logs the process IDs of each
162 process and it's parent. Note that this file format is incompatible
163 with previous v0/v1/v2 file formats, so you will need updated tools
164 for processing it. A preliminary version of these tools is available
165 at <http://www.physik3.uni-rostock.de/tim/kernel/utils/acct/>.
166
Shailabh Nagarc7572492006-07-14 00:24:40 -0700167config TASKSTATS
168 bool "Export task/process statistics through netlink (EXPERIMENTAL)"
169 depends on NET
170 default n
171 help
172 Export selected statistics for tasks/processes through the
173 generic netlink interface. Unlike BSD process accounting, the
174 statistics are available during the lifetime of tasks/processes as
175 responses to commands. Like BSD accounting, they are sent to user
176 space on task exit.
177
178 Say N if unsure.
179
Shailabh Nagarca74e922006-07-14 00:24:36 -0700180config TASK_DELAY_ACCT
181 bool "Enable per-task delay accounting (EXPERIMENTAL)"
Shailabh Nagar6f449932006-07-14 00:24:41 -0700182 depends on TASKSTATS
Shailabh Nagarca74e922006-07-14 00:24:36 -0700183 help
184 Collect information on time spent by a task waiting for system
185 resources like cpu, synchronous block I/O completion and swapping
186 in pages. Such statistics can help in setting a task's priorities
187 relative to other tasks for cpu, io, rss limits etc.
188
189 Say N if unsure.
190
Alexey Dobriyan18f705f2007-02-10 01:46:44 -0800191config TASK_XACCT
192 bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
193 depends on TASKSTATS
194 help
195 Collect extended task accounting data and send the data
196 to userland for processing over the taskstats interface.
197
198 Say N if unsure.
199
200config TASK_IO_ACCOUNTING
201 bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
202 depends on TASK_XACCT
203 help
204 Collect information on the number of bytes of storage I/O which this
205 task has caused.
206
207 Say N if unsure.
208
Cedric Le Goateracce2922007-07-15 23:40:59 -0700209config USER_NS
210 bool "User Namespaces (EXPERIMENTAL)"
211 default n
212 depends on EXPERIMENTAL
213 help
214 Support user namespaces. This allows containers, i.e.
215 vservers, to use user namespaces to provide different
216 user info for different servers. If unsure, say N.
217
Eric W. Biederman57d5f662007-11-14 17:00:13 -0800218config PID_NS
219 bool "PID Namespaces (EXPERIMENTAL)"
220 default n
221 depends on EXPERIMENTAL
222 help
223 Suport process id namespaces. This allows having multiple
224 process with the same pid as long as they are in different
225 pid namespaces. This is a building block of containers.
226
227 Unless you want to work with an experimental feature
228 say N here.
229
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230config AUDIT
231 bool "Auditing support"
Chris Wright804a6a492005-05-11 10:52:45 +0100232 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 help
234 Enable auditing infrastructure that can be used with another
235 kernel subsystem, such as SELinux (which requires this for
236 logging of avc messages output). Does not do system-call
237 auditing without CONFIG_AUDITSYSCALL.
238
239config AUDITSYSCALL
240 bool "Enable system-call auditing support"
Yuichi Nakamura1322b9d2007-11-10 19:21:34 +0900241 depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64|| SUPERH)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 default y if SECURITY_SELINUX
243 help
244 Enable low-overhead system-call auditing infrastructure that
245 can be used independently or with another kernel subsystem,
Amy Griffisf368c07d2006-04-07 16:55:56 -0400246 such as SELinux. To use audit's filesystem watch feature, please
247 ensure that INOTIFY is configured.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248
Al Viro74c3cbe2007-07-22 08:04:18 -0400249config AUDIT_TREE
250 def_bool y
251 depends on AUDITSYSCALL && INOTIFY
252
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700254 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255 ---help---
256 This option enables the complete Linux kernel ".config" file
257 contents to be saved in the kernel. It provides documentation
258 of which kernel options are used in a running kernel or in an
259 on-disk kernel. This information can be extracted from the kernel
260 image file with the script scripts/extract-ikconfig and used as
261 input to rebuild the current kernel or to build another kernel.
262 It can also be extracted from a running kernel by reading
263 /proc/config.gz if enabled (below).
264
265config IKCONFIG_PROC
266 bool "Enable access to .config through /proc/config.gz"
267 depends on IKCONFIG && PROC_FS
268 ---help---
269 This option enables access to the kernel configuration file
270 through /proc/config.gz.
271
Alistair John Strachan794543a2007-05-08 00:31:15 -0700272config LOG_BUF_SHIFT
273 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
274 range 12 21
275 default 17 if S390 || LOCKDEP
276 default 16 if X86_NUMAQ || IA64
277 default 15 if SMP
278 default 14
279 help
280 Select kernel log buffer size as a power of 2.
281 Defaults and Examples:
282 17 => 128 KB for S/390
283 16 => 64 KB for x86 NUMAQ or IA-64
284 15 => 32 KB for SMP
285 14 => 16 KB for uniprocessor
286 13 => 8 KB
287 12 => 4 KB
288
Paul Menageddbcc7e2007-10-18 23:39:30 -0700289config CGROUPS
290 bool "Control Group support"
291 help
292 This option will let you use process cgroup subsystems
293 such as Cpusets
294
295 Say N if unsure.
296
Paul Menage006cb992007-10-18 23:39:43 -0700297config CGROUP_DEBUG
298 bool "Example debug cgroup subsystem"
299 depends on CGROUPS
300 help
301 This option enables a simple cgroup subsystem that
302 exports useful debugging information about the cgroups
303 framework
304
305 Say N if unsure
306
Serge E. Hallyn858d72e2007-10-18 23:39:45 -0700307config CGROUP_NS
308 bool "Namespace cgroup subsystem"
309 depends on CGROUPS
310 help
311 Provides a simple namespace cgroup subsystem to
312 provide hierarchical naming of sets of namespaces,
313 for instance virtual servers and checkpoint/restart
314 jobs.
315
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316config CPUSETS
317 bool "Cpuset support"
Paul Menage8793d852007-10-18 23:39:39 -0700318 depends on SMP && CGROUPS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700320 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 allow dynamically partitioning a system into sets of CPUs and
322 Memory Nodes and assigning tasks to run only within those sets.
323 This is primarily useful on large SMP or NUMA systems.
324
325 Say N if unsure.
326
Srivatsa Vaddagiri29f59db2007-10-15 17:00:07 +0200327config FAIR_GROUP_SCHED
Srivatsa Vaddagirifb615582007-10-15 17:00:12 +0200328 bool "Fair group CPU scheduler"
Ingo Molnarde8d5852007-10-15 17:00:09 +0200329 default y
Srivatsa Vaddagiri29f59db2007-10-15 17:00:07 +0200330 help
Srivatsa Vaddagirifb615582007-10-15 17:00:12 +0200331 This feature lets CPU scheduler recognize task groups and control CPU
Srivatsa Vaddagiri9b5b7752007-10-15 17:00:09 +0200332 bandwidth allocation to such task groups.
Srivatsa Vaddagiri29f59db2007-10-15 17:00:07 +0200333
Srivatsa Vaddagiri24e377a2007-10-15 17:00:09 +0200334choice
335 depends on FAIR_GROUP_SCHED
336 prompt "Basis for grouping tasks"
337 default FAIR_USER_SCHED
338
Srivatsa Vaddagirifb615582007-10-15 17:00:12 +0200339config FAIR_USER_SCHED
340 bool "user id"
341 help
342 This option will choose userid as the basis for grouping
343 tasks, thus providing equal CPU bandwidth to each user.
Srivatsa Vaddagiri24e377a2007-10-15 17:00:09 +0200344
Srivatsa Vaddagiri68318b82007-10-18 23:41:03 -0700345config FAIR_CGROUP_SCHED
346 bool "Control groups"
347 depends on CGROUPS
348 help
349 This option allows you to create arbitrary task groups
350 using the "cgroup" pseudo filesystem and control
351 the cpu bandwidth allocated to each such task group.
352 Refer to Documentation/cgroups.txt for more information
353 on "cgroup" pseudo filesystem.
354
Srivatsa Vaddagiri24e377a2007-10-15 17:00:09 +0200355endchoice
356
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100357config CGROUP_CPUACCT
358 bool "Simple CPU accounting cgroup subsystem"
359 depends on CGROUPS
360 help
361 Provides a simple Resource Controller for monitoring the
362 total CPU consumed by the tasks in a cgroup
363
Kay Sievers88a22c92006-09-14 11:23:28 +0200364config SYSFS_DEPRECATED
365 bool "Create deprecated sysfs files"
Randy Dunlap9148fe82007-12-31 10:05:34 -0800366 depends on SYSFS
Kay Sievers88a22c92006-09-14 11:23:28 +0200367 default y
368 help
369 This option creates deprecated symlinks such as the
370 "device"-link, the <subsystem>:<name>-link, and the
371 "bus"-link. It may also add deprecated key in the
372 uevent environment.
373 None of these features or values should be used today, as
374 they export driver core implementation details to userspace
375 or export properties which can't be kept stable across kernel
376 releases.
377
378 If enabled, this option will also move any device structures
David Sterba3dde6ad2007-05-09 07:12:20 +0200379 that belong to a class, back into the /sys/class hierarchy, in
Kay Sievers88a22c92006-09-14 11:23:28 +0200380 order to support older versions of udev.
381
382 If you are using a distro that was released in 2006 or later,
383 it should be safe to say N here.
384
Paul Menage8793d852007-10-18 23:39:39 -0700385config PROC_PID_CPUSET
386 bool "Include legacy /proc/<pid>/cpuset file"
387 depends on CPUSETS
388 default y
389
Jens Axboeb86ff9812006-03-23 19:56:55 +0100390config RELAY
391 bool "Kernel->user space relay support (formerly relayfs)"
392 help
393 This option enables support for relay interface support in
394 certain file systems (such as debugfs).
395 It is designed to provide an efficient mechanism for tools and
396 facilities to relay large amounts of data from kernel space to
397 user space.
398
399 If unsure, say N.
400
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -0800401config BLK_DEV_INITRD
402 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
403 depends on BROKEN || !FRV
404 help
405 The initial RAM filesystem is a ramfs which is loaded by the
406 boot loader (loadlin or lilo) and that is mounted as root
407 before the normal boot procedure. It is typically used to
408 load modules needed to mount the "real" root file system,
409 etc. See <file:Documentation/initrd.txt> for details.
410
411 If RAM disk support (BLK_DEV_RAM) is also included, this
412 also enables initial RAM disk (initrd) support and adds
413 15 Kbytes (more on some other architectures) to the kernel size.
414
415 If unsure say Y.
416
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800417if BLK_DEV_INITRD
418
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200419source "usr/Kconfig"
420
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800421endif
422
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800423config CC_OPTIMIZE_FOR_SIZE
424 bool "Optimize for size (Look out for broken compilers!)"
425 default y
Paul Mundt32582fa2007-07-25 11:27:05 +0900426 depends on ARM || H8300 || SUPERH || EXPERIMENTAL
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800427 help
428 Enabling this option will pass "-Os" instead of "-O2" to gcc
429 resulting in a smaller kernel.
430
431 WARNING: some versions of gcc may generate incorrect code with this
432 option. If problems are observed, a gcc upgrade may be needed.
433
434 If unsure, say N.
435
Randy Dunlap08470622006-09-30 23:28:13 -0700436config SYSCTL
437 bool
438
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439menuconfig EMBEDDED
440 bool "Configure standard kernel features (for small systems)"
441 help
442 This option allows certain base kernel options and settings
443 to be disabled or tweaked. This is for specialized
444 environments which can tolerate a "non-standard" kernel.
445 Only use this if you really know what you are doing.
446
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700447config UID16
448 bool "Enable 16-bit UID system calls" if EMBEDDED
Mike Frysinger529a73f2007-11-23 14:28:44 +0800449 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 -0700450 default y
451 help
452 This enables the legacy 16-bit UID syscall wrappers.
453
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700454config SYSCTL_SYSCALL
Randy Dunlap08470622006-09-30 23:28:13 -0700455 bool "Sysctl syscall support" if EMBEDDED
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800456 default y
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700457 select SYSCTL
458 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800459 sys_sysctl uses binary paths that have been found challenging
460 to properly maintain and use. The interface in /proc/sys
461 using paths with ascii names is now the primary path to this
462 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700463
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800464 Almost nothing using the binary sysctl interface so if you are
465 trying to save some space it is probably safe to disable this,
466 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700467
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800468 If unsure say Y here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700469
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470config KALLSYMS
Jesper Juhl979c6a12006-12-12 19:25:11 +0100471 bool "Load all symbols for debugging/ksymoops" if EMBEDDED
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472 default y
473 help
474 Say Y here to let the kernel print out symbolic crash information and
475 symbolic stack backtraces. This increases the size of the kernel
476 somewhat, as all symbols have to be loaded into the kernel image.
477
478config KALLSYMS_ALL
479 bool "Include all symbols in kallsyms"
480 depends on DEBUG_KERNEL && KALLSYMS
481 help
482 Normally kallsyms only contains the symbols of functions, for nicer
483 OOPS messages. Some debuggers can use kallsyms for other
Jesper Juhlf9f97bc2005-07-20 05:43:05 +0200484 symbols too: say Y here to include all symbols, if you need them
485 and you don't care about adding 300k to the size of your kernel.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486
487 Say N.
488
489config KALLSYMS_EXTRA_PASS
490 bool "Do an extra kallsyms pass"
491 depends on KALLSYMS
492 help
493 If kallsyms is not working correctly, the build will fail with
494 inconsistent kallsyms data. If that occurs, log a bug report and
495 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
496 Always say N here unless you find a bug in kallsyms, which must be
497 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
498 you wait for kallsyms to be fixed.
499
Matt Mackalld59745c2005-05-01 08:59:02 -0700500
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -0800501config HOTPLUG
502 bool "Support for hot-pluggable devices" if EMBEDDED
503 default y
504 help
505 This option is provided for the case where no hotplug or uevent
506 capabilities is wanted by the kernel. You should only consider
507 disabling this option for embedded systems that do not use modules, a
508 dynamic /dev tree, or dynamic device discovery. Just say Y.
509
Matt Mackalld59745c2005-05-01 08:59:02 -0700510config PRINTK
511 default y
512 bool "Enable support for printk" if EMBEDDED
513 help
514 This option enables normal printk support. Removing it
515 eliminates most of the message strings from the kernel image
516 and makes the kernel more or less silent. As this makes it
517 very difficult to diagnose system problems, saying N here is
518 strongly discouraged.
519
Matt Mackallc8538a72005-05-01 08:59:01 -0700520config BUG
521 bool "BUG() support" if EMBEDDED
522 default y
523 help
524 Disabling this option eliminates support for BUG and WARN, reducing
525 the size of your kernel image and potentially quietly ignoring
526 numerous fatal conditions. You should only consider disabling this
527 option for embedded systems with no facilities for reporting errors.
528 Just say Y.
529
Matt Mackall708e9a72006-01-08 01:05:25 -0800530config ELF_CORE
531 default y
532 bool "Enable ELF core dumps" if EMBEDDED
533 help
534 Enable support for generating core dumps. Disabling saves about 4k.
535
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536config BASE_FULL
537 default y
538 bool "Enable full-sized data structures for core" if EMBEDDED
539 help
540 Disabling this option reduces the size of miscellaneous core
541 kernel data structures. This saves memory on small machines,
542 but may reduce performance.
543
544config FUTEX
545 bool "Enable futex support" if EMBEDDED
546 default y
Ingo Molnar23f78d4a2006-06-27 02:54:53 -0700547 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548 help
549 Disabling this option will cause the kernel to be built without
550 support for "fast userspace mutexes". The resulting kernel may not
551 run glibc-based applications correctly.
552
Davide Libenzi5dc8bf82007-05-10 22:23:11 -0700553config ANON_INODES
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700554 bool
Davide Libenzi5dc8bf82007-05-10 22:23:11 -0700555
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556config EPOLL
557 bool "Enable eventpoll support" if EMBEDDED
558 default y
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700559 select ANON_INODES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 help
561 Disabling this option will cause the kernel to be built without
562 support for epoll family of system calls.
563
Davide Libenzifba2afa2007-05-10 22:23:13 -0700564config SIGNALFD
565 bool "Enable signalfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700566 select ANON_INODES
Davide Libenzifba2afa2007-05-10 22:23:13 -0700567 default y
568 help
569 Enable the signalfd() system call that allows to receive signals
570 on a file descriptor.
571
572 If unsure, say Y.
573
Davide Libenzib215e282007-05-10 22:23:16 -0700574config TIMERFD
575 bool "Enable timerfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700576 select ANON_INODES
Andrew Mortone4260192007-09-18 22:46:41 -0700577 depends on BROKEN
Davide Libenzib215e282007-05-10 22:23:16 -0700578 default y
579 help
580 Enable the timerfd() system call that allows to receive timer
581 events on a file descriptor.
582
583 If unsure, say Y.
584
Davide Libenzie1ad7462007-05-10 22:23:19 -0700585config EVENTFD
586 bool "Enable eventfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700587 select ANON_INODES
Davide Libenzie1ad7462007-05-10 22:23:19 -0700588 default y
589 help
590 Enable the eventfd() system call that allows to receive both
591 kernel notification (ie. KAIO) or userspace notifications.
592
593 If unsure, say Y.
594
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595config SHMEM
596 bool "Use full shmem filesystem" if EMBEDDED
597 default y
598 depends on MMU
599 help
600 The shmem is an internal filesystem used to manage shared memory.
601 It is backed by swap and manages resource limits. It is also exported
602 to userspace as tmpfs if TMPFS is enabled. Disabling this
603 option replaces shmem and tmpfs with the much simpler ramfs code,
604 which may be appropriate on small systems without swap.
605
Christoph Lameterf8891e52006-06-30 01:55:45 -0700606config VM_EVENT_COUNTERS
607 default y
608 bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
609 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -0800610 VM event counters are needed for event counts to be shown.
611 This option allows the disabling of the VM event counters
612 on EMBEDDED systems. /proc/vmstat will only show page counts
613 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -0700614
Christoph Lameter41ecc552007-05-09 02:32:44 -0700615config SLUB_DEBUG
616 default y
617 bool "Enable SLUB debugging support" if EMBEDDED
Christoph Lameterd4751a22007-05-10 03:15:40 -0700618 depends on SLUB
Christoph Lameter41ecc552007-05-09 02:32:44 -0700619 help
620 SLUB has extensive debug support features. Disabling these can
621 result in significant savings in code size. This also disables
622 SLUB sysfs support. /sys/slab will not exist and there will be
623 no support for cache validation etc.
624
Christoph Lameter81819f02007-05-06 14:49:36 -0700625choice
626 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -0700627 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -0700628 help
629 This option allows to select a slab allocator.
630
631config SLAB
632 bool "SLAB"
633 help
634 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -0700635 well in all environments. It organizes cache hot objects in
Christoph Lameter81819f02007-05-06 14:49:36 -0700636 per cpu and per node queues. SLAB is the default choice for
Christoph Lameter34013882007-05-09 02:32:47 -0700637 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -0700638
639config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -0700640 bool "SLUB (Unqueued Allocator)"
641 help
642 SLUB is a slab allocator that minimizes cache line usage
643 instead of managing queues of cached objects (SLAB approach).
644 Per cpu caching is realized using slabs of objects instead
645 of queues of objects. SLUB can use memory efficiently
Christoph Lameter34013882007-05-09 02:32:47 -0700646 and has enhanced diagnostics.
Christoph Lameter81819f02007-05-06 14:49:36 -0700647
648config SLOB
Paul Mundt84a01c22007-07-15 23:38:24 -0700649 depends on EMBEDDED
Christoph Lameter81819f02007-05-06 14:49:36 -0700650 bool "SLOB (Simple Allocator)"
651 help
652 SLOB replaces the SLAB allocator with a drastically simpler
Nick Pigginafc0ced2007-05-16 22:10:49 -0700653 allocator. SLOB is more space efficient than SLAB but does not
Christoph Lameter34013882007-05-09 02:32:47 -0700654 scale well (single lock for all operations) and is also highly
655 susceptible to fragmentation. SLUB can accomplish a higher object
656 density. It is usually better to use SLUB instead of SLOB.
Christoph Lameter81819f02007-05-06 14:49:36 -0700657
658endchoice
659
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660endmenu # General setup
661
Linus Torvalds158a9622008-01-02 13:04:48 -0800662config SLABINFO
663 bool
664 depends on PROC_FS
665 depends on SLAB || SLUB
666 default y
667
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700668config RT_MUTEXES
669 boolean
670 select PLIST
671
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672config TINY_SHMEM
673 default !SHMEM
674 bool
675
676config BASE_SMALL
677 int
678 default 0 if BASE_FULL
679 default 1 if !BASE_FULL
680
Jan Engelhardt66da5732007-07-15 23:39:29 -0700681menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682 bool "Enable loadable module support"
683 help
684 Kernel modules are small pieces of compiled code which can
685 be inserted in the running kernel, rather than being
686 permanently built into the kernel. You use the "modprobe"
687 tool to add (and sometimes remove) them. If you say Y here,
688 many parts of the kernel can be built as modules (by
689 answering M instead of Y where indicated): this is most
690 useful for infrequently used options which are not required
691 for booting. For more information, see the man pages for
692 modprobe, lsmod, modinfo, insmod and rmmod.
693
694 If you say Y here, you will need to run "make
695 modules_install" to put the modules under /lib/modules/
696 where modprobe can find them (you may need to be root to do
697 this).
698
699 If unsure, say Y.
700
701config MODULE_UNLOAD
702 bool "Module unloading"
703 depends on MODULES
704 help
705 Without this option you will not be able to unload any
706 modules (note that some modules may not be unloadable
707 anyway), which makes your kernel slightly smaller and
708 simpler. If unsure, say Y.
709
710config MODULE_FORCE_UNLOAD
711 bool "Forced module unloading"
712 depends on MODULE_UNLOAD && EXPERIMENTAL
713 help
714 This option allows you to force a module to unload, even if the
715 kernel believes it is unsafe: the kernel will remove the module
716 without waiting for anyone to stop using it (using the -f option to
717 rmmod). This is mainly for kernel developers and desperate users.
718 If unsure, say N.
719
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +0100721 bool "Module versioning support"
722 depends on MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723 help
724 Usually, you have to use modules compiled with your kernel.
725 Saying Y here makes it sometimes possible to use modules
726 compiled for different kernels, by adding enough information
727 to the modules to (hopefully) spot any changes which would
728 make them incompatible with the kernel you are running. If
729 unsure, say N.
730
731config MODULE_SRCVERSION_ALL
732 bool "Source checksum for all modules"
733 depends on MODULES
734 help
735 Modules which contain a MODULE_VERSION get an extra "srcversion"
736 field inserted into their modinfo section, which contains a
737 sum of the source files which made it. This helps maintainers
738 see exactly which source was used to build a module (since
739 others sometimes change the module source without updating
740 the version). With this option, such a "srcversion" field
741 will be created for all modules. If unsure, say N.
742
743config KMOD
744 bool "Automatic kernel module loading"
745 depends on MODULES
746 help
747 Normally when you have selected some parts of the kernel to
748 be created as kernel modules, you must load them (using the
749 "modprobe" command) before you can use them. If you say Y
750 here, some parts of the kernel will be able to load modules
751 automatically: when a part of the kernel needs a module, it
752 runs modprobe with the appropriate arguments, thereby
753 loading the module if it is available. If unsure, say Y.
754
755config STOP_MACHINE
756 bool
757 default y
758 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
759 help
760 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +0100761
Jens Axboe3a65dfe2005-11-04 08:43:35 +0100762source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -0700763
764config PREEMPT_NOTIFIERS
765 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +0100766
767choice
768 prompt "RCU implementation type:"
769 default CLASSIC_RCU
770
771config CLASSIC_RCU
772 bool "Classic RCU"
773 help
774 This option selects the classic RCU implementation that is
775 designed for best read-side performance on non-realtime
776 systems.
777
778 Say Y if you are unsure.
779
780config PREEMPT_RCU
781 bool "Preemptible RCU"
782 depends on PREEMPT
783 help
784 This option reduces the latency of the kernel by making certain
785 RCU sections preemptible. Normally RCU code is non-preemptible, if
786 this option is selected then read-only RCU sections become
787 preemptible. This helps latency, but may expose bugs due to
788 now-naive assumptions about each RCU read-side critical section
789 remaining on a given CPU through its execution.
790
791 Say N if you are unsure.
792
793endchoice