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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
Linus Torvalds1da177e2005-04-16 15:20:36 -070010menu "Code maturity level options"
11
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33 drivers that have been replaced by something else, and/or are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
64endmenu
65
66menu "General setup"
67
68config LOCALVERSION
69 string "Local version - append to kernel release"
70 help
71 Append an extra string to the end of your kernel version.
72 This will show up when you type uname, for example.
73 The string you set here will be appended after the contents of
74 any files with a filename matching localversion* in your
75 object and source tree, in that order. Your total string can
76 be a maximum of 64 characters.
77
Ryan Andersonaaebf432005-07-31 04:57:49 -040078config LOCALVERSION_AUTO
79 bool "Automatically append version information to the version string"
80 default y
81 help
82 This will try to automatically determine if the current tree is a
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020083 release tree by looking for git tags that belong to the current
84 top of tree revision.
Ryan Andersonaaebf432005-07-31 04:57:49 -040085
86 A string of the format -gxxxxxxxx will be added to the localversion
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020087 if a git-based tree is found. The string generated by this will be
Ryan Andersonaaebf432005-07-31 04:57:49 -040088 appended after any matching localversion* files, and after the value
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020089 set in CONFIG_LOCALVERSION.
Ryan Andersonaaebf432005-07-31 04:57:49 -040090
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020091 (The actual string used here is the first eight characters produced
92 by running the command:
93
94 $ git rev-parse --verify HEAD
95
96 which is done within the script "scripts/setlocalversion".)
Ryan Andersonaaebf432005-07-31 04:57:49 -040097
Linus Torvalds1da177e2005-04-16 15:20:36 -070098config SWAP
99 bool "Support for paging of anonymous memory (swap)"
David Howells93614012006-09-30 20:45:40 +0200100 depends on MMU && BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101 default y
102 help
103 This option allows you to choose whether you want to have support
Jesper Juhl92c35042006-01-15 02:40:08 +0100104 for so called swap devices or swap files in your kernel that are
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105 used to provide more virtual memory than the actual RAM present
106 in your computer. If unsure say Y.
107
108config SYSVIPC
109 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 ---help---
111 Inter Process Communication is a suite of library functions and
112 system calls which let processes (running programs) synchronize and
113 exchange information. It is generally considered to be a good thing,
114 and some programs won't run unless you say Y here. In particular, if
115 you want to run the DOS emulator dosemu under Linux (read the
116 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
117 you'll need to say Y here.
118
119 You can find documentation about IPC with "info ipc" and also in
120 section 6.4 of the Linux Programmer's Guide, available from
121 <http://www.tldp.org/guides.html>.
122
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700123config IPC_NS
124 bool "IPC Namespaces"
125 depends on SYSVIPC
126 default n
127 help
128 Support ipc namespaces. This allows containers, i.e. virtual
129 environments, to use ipc namespaces to provide different ipc
130 objects for different servers. If unsure, say N.
131
Eric W. Biedermana5494dc2007-02-14 00:34:06 -0800132config SYSVIPC_SYSCTL
133 bool
134 depends on SYSVIPC
135 depends on SYSCTL
136 default y
137
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138config POSIX_MQUEUE
139 bool "POSIX Message Queues"
140 depends on NET && EXPERIMENTAL
141 ---help---
142 POSIX variant of message queues is a part of IPC. In POSIX message
143 queues every message has a priority which decides about succession
144 of receiving it by a process. If you want to compile and run
145 programs written e.g. for Solaris with use of its POSIX message
146 queues (functions mq_*) say Y here. To use this feature you will
147 also need mqueue library, available from
148 <http://www.mat.uni.torun.pl/~wrona/posix_ipc/>
149
150 POSIX message queues are visible as a filesystem called 'mqueue'
151 and can be mounted somewhere if you want to do filesystem
152 operations on message queues.
153
154 If unsure, say Y.
155
156config BSD_PROCESS_ACCT
157 bool "BSD Process Accounting"
158 help
159 If you say Y here, a user level program will be able to instruct the
160 kernel (via a special system call) to write process accounting
161 information to a file: whenever a process exits, information about
162 that process will be appended to the file by the kernel. The
163 information includes things such as creation time, owning user,
164 command name, memory usage, controlling terminal etc. (the complete
165 list is in the struct acct in <file:include/linux/acct.h>). It is
166 up to the user level program to do useful things with this
167 information. This is generally a good idea, so say Y.
168
169config BSD_PROCESS_ACCT_V3
170 bool "BSD Process Accounting version 3 file format"
171 depends on BSD_PROCESS_ACCT
172 default n
173 help
174 If you say Y here, the process accounting information is written
175 in a new file format that also logs the process IDs of each
176 process and it's parent. Note that this file format is incompatible
177 with previous v0/v1/v2 file formats, so you will need updated tools
178 for processing it. A preliminary version of these tools is available
179 at <http://www.physik3.uni-rostock.de/tim/kernel/utils/acct/>.
180
Shailabh Nagarc7572492006-07-14 00:24:40 -0700181config TASKSTATS
182 bool "Export task/process statistics through netlink (EXPERIMENTAL)"
183 depends on NET
184 default n
185 help
186 Export selected statistics for tasks/processes through the
187 generic netlink interface. Unlike BSD process accounting, the
188 statistics are available during the lifetime of tasks/processes as
189 responses to commands. Like BSD accounting, they are sent to user
190 space on task exit.
191
192 Say N if unsure.
193
Shailabh Nagarca74e922006-07-14 00:24:36 -0700194config TASK_DELAY_ACCT
195 bool "Enable per-task delay accounting (EXPERIMENTAL)"
Shailabh Nagar6f449932006-07-14 00:24:41 -0700196 depends on TASKSTATS
Shailabh Nagarca74e922006-07-14 00:24:36 -0700197 help
198 Collect information on time spent by a task waiting for system
199 resources like cpu, synchronous block I/O completion and swapping
200 in pages. Such statistics can help in setting a task's priorities
201 relative to other tasks for cpu, io, rss limits etc.
202
203 Say N if unsure.
204
Alexey Dobriyan18f705f2007-02-10 01:46:44 -0800205config TASK_XACCT
206 bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
207 depends on TASKSTATS
208 help
209 Collect extended task accounting data and send the data
210 to userland for processing over the taskstats interface.
211
212 Say N if unsure.
213
214config TASK_IO_ACCOUNTING
215 bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
216 depends on TASK_XACCT
217 help
218 Collect information on the number of bytes of storage I/O which this
219 task has caused.
220
221 Say N if unsure.
222
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -0700223config UTS_NS
224 bool "UTS Namespaces"
225 default n
226 help
227 Support uts namespaces. This allows containers, i.e.
228 vservers, to use uts namespaces to provide different
229 uts info for different servers. If unsure, say N.
230
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231config AUDIT
232 bool "Auditing support"
Chris Wright804a6a492005-05-11 10:52:45 +0100233 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234 help
235 Enable auditing infrastructure that can be used with another
236 kernel subsystem, such as SELinux (which requires this for
237 logging of avc messages output). Does not do system-call
238 auditing without CONFIG_AUDITSYSCALL.
239
240config AUDITSYSCALL
241 bool "Enable system-call auditing support"
Martin Schwidefsky347a8dc2006-01-06 00:19:28 -0800242 depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 default y if SECURITY_SELINUX
244 help
245 Enable low-overhead system-call auditing infrastructure that
246 can be used independently or with another kernel subsystem,
Amy Griffisf368c07d2006-04-07 16:55:56 -0400247 such as SELinux. To use audit's filesystem watch feature, please
248 ensure that INOTIFY is configured.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700251 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 ---help---
253 This option enables the complete Linux kernel ".config" file
254 contents to be saved in the kernel. It provides documentation
255 of which kernel options are used in a running kernel or in an
256 on-disk kernel. This information can be extracted from the kernel
257 image file with the script scripts/extract-ikconfig and used as
258 input to rebuild the current kernel or to build another kernel.
259 It can also be extracted from a running kernel by reading
260 /proc/config.gz if enabled (below).
261
262config IKCONFIG_PROC
263 bool "Enable access to .config through /proc/config.gz"
264 depends on IKCONFIG && PROC_FS
265 ---help---
266 This option enables access to the kernel configuration file
267 through /proc/config.gz.
268
Alistair John Strachan794543a2007-05-08 00:31:15 -0700269config LOG_BUF_SHIFT
270 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
271 range 12 21
272 default 17 if S390 || LOCKDEP
273 default 16 if X86_NUMAQ || IA64
274 default 15 if SMP
275 default 14
276 help
277 Select kernel log buffer size as a power of 2.
278 Defaults and Examples:
279 17 => 128 KB for S/390
280 16 => 64 KB for x86 NUMAQ or IA-64
281 15 => 32 KB for SMP
282 14 => 16 KB for uniprocessor
283 13 => 8 KB
284 12 => 4 KB
285
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286config CPUSETS
287 bool "Cpuset support"
288 depends on SMP
289 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700290 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 allow dynamically partitioning a system into sets of CPUs and
292 Memory Nodes and assigning tasks to run only within those sets.
293 This is primarily useful on large SMP or NUMA systems.
294
295 Say N if unsure.
296
Kay Sievers88a22c92006-09-14 11:23:28 +0200297config SYSFS_DEPRECATED
298 bool "Create deprecated sysfs files"
299 default y
300 help
301 This option creates deprecated symlinks such as the
302 "device"-link, the <subsystem>:<name>-link, and the
303 "bus"-link. It may also add deprecated key in the
304 uevent environment.
305 None of these features or values should be used today, as
306 they export driver core implementation details to userspace
307 or export properties which can't be kept stable across kernel
308 releases.
309
310 If enabled, this option will also move any device structures
311 that belong to a class, back into the /sys/class heirachy, in
312 order to support older versions of udev.
313
314 If you are using a distro that was released in 2006 or later,
315 it should be safe to say N here.
316
Jens Axboeb86ff9812006-03-23 19:56:55 +0100317config RELAY
318 bool "Kernel->user space relay support (formerly relayfs)"
319 help
320 This option enables support for relay interface support in
321 certain file systems (such as debugfs).
322 It is designed to provide an efficient mechanism for tools and
323 facilities to relay large amounts of data from kernel space to
324 user space.
325
326 If unsure, say N.
327
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -0800328config BLK_DEV_INITRD
329 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
330 depends on BROKEN || !FRV
331 help
332 The initial RAM filesystem is a ramfs which is loaded by the
333 boot loader (loadlin or lilo) and that is mounted as root
334 before the normal boot procedure. It is typically used to
335 load modules needed to mount the "real" root file system,
336 etc. See <file:Documentation/initrd.txt> for details.
337
338 If RAM disk support (BLK_DEV_RAM) is also included, this
339 also enables initial RAM disk (initrd) support and adds
340 15 Kbytes (more on some other architectures) to the kernel size.
341
342 If unsure say Y.
343
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800344if BLK_DEV_INITRD
345
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200346source "usr/Kconfig"
347
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800348endif
349
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800350config CC_OPTIMIZE_FOR_SIZE
351 bool "Optimize for size (Look out for broken compilers!)"
352 default y
353 depends on ARM || H8300 || EXPERIMENTAL
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800354 help
355 Enabling this option will pass "-Os" instead of "-O2" to gcc
356 resulting in a smaller kernel.
357
358 WARNING: some versions of gcc may generate incorrect code with this
359 option. If problems are observed, a gcc upgrade may be needed.
360
361 If unsure, say N.
362
Randy Dunlap08470622006-09-30 23:28:13 -0700363config SYSCTL
364 bool
365
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366menuconfig EMBEDDED
367 bool "Configure standard kernel features (for small systems)"
368 help
369 This option allows certain base kernel options and settings
370 to be disabled or tweaked. This is for specialized
371 environments which can tolerate a "non-standard" kernel.
372 Only use this if you really know what you are doing.
373
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700374config UID16
375 bool "Enable 16-bit UID system calls" if EMBEDDED
Bryan Wu1394f032007-05-06 14:50:22 -0700376 depends on ARM || BFIN || 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 -0700377 default y
378 help
379 This enables the legacy 16-bit UID syscall wrappers.
380
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700381config SYSCTL_SYSCALL
Randy Dunlap08470622006-09-30 23:28:13 -0700382 bool "Sysctl syscall support" if EMBEDDED
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800383 default y
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700384 select SYSCTL
385 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800386 sys_sysctl uses binary paths that have been found challenging
387 to properly maintain and use. The interface in /proc/sys
388 using paths with ascii names is now the primary path to this
389 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700390
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800391 Almost nothing using the binary sysctl interface so if you are
392 trying to save some space it is probably safe to disable this,
393 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700394
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800395 If unsure say Y here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700396
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397config KALLSYMS
Jesper Juhl979c6a12006-12-12 19:25:11 +0100398 bool "Load all symbols for debugging/ksymoops" if EMBEDDED
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399 default y
400 help
401 Say Y here to let the kernel print out symbolic crash information and
402 symbolic stack backtraces. This increases the size of the kernel
403 somewhat, as all symbols have to be loaded into the kernel image.
404
405config KALLSYMS_ALL
406 bool "Include all symbols in kallsyms"
407 depends on DEBUG_KERNEL && KALLSYMS
408 help
409 Normally kallsyms only contains the symbols of functions, for nicer
410 OOPS messages. Some debuggers can use kallsyms for other
Jesper Juhlf9f97bc2005-07-20 05:43:05 +0200411 symbols too: say Y here to include all symbols, if you need them
412 and you don't care about adding 300k to the size of your kernel.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413
414 Say N.
415
416config KALLSYMS_EXTRA_PASS
417 bool "Do an extra kallsyms pass"
418 depends on KALLSYMS
419 help
420 If kallsyms is not working correctly, the build will fail with
421 inconsistent kallsyms data. If that occurs, log a bug report and
422 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
423 Always say N here unless you find a bug in kallsyms, which must be
424 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
425 you wait for kallsyms to be fixed.
426
Matt Mackalld59745c2005-05-01 08:59:02 -0700427
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -0800428config HOTPLUG
429 bool "Support for hot-pluggable devices" if EMBEDDED
430 default y
431 help
432 This option is provided for the case where no hotplug or uevent
433 capabilities is wanted by the kernel. You should only consider
434 disabling this option for embedded systems that do not use modules, a
435 dynamic /dev tree, or dynamic device discovery. Just say Y.
436
Matt Mackalld59745c2005-05-01 08:59:02 -0700437config PRINTK
438 default y
439 bool "Enable support for printk" if EMBEDDED
440 help
441 This option enables normal printk support. Removing it
442 eliminates most of the message strings from the kernel image
443 and makes the kernel more or less silent. As this makes it
444 very difficult to diagnose system problems, saying N here is
445 strongly discouraged.
446
Matt Mackallc8538a72005-05-01 08:59:01 -0700447config BUG
448 bool "BUG() support" if EMBEDDED
449 default y
450 help
451 Disabling this option eliminates support for BUG and WARN, reducing
452 the size of your kernel image and potentially quietly ignoring
453 numerous fatal conditions. You should only consider disabling this
454 option for embedded systems with no facilities for reporting errors.
455 Just say Y.
456
Matt Mackall708e9a72006-01-08 01:05:25 -0800457config ELF_CORE
458 default y
459 bool "Enable ELF core dumps" if EMBEDDED
460 help
461 Enable support for generating core dumps. Disabling saves about 4k.
462
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463config BASE_FULL
464 default y
465 bool "Enable full-sized data structures for core" if EMBEDDED
466 help
467 Disabling this option reduces the size of miscellaneous core
468 kernel data structures. This saves memory on small machines,
469 but may reduce performance.
470
471config FUTEX
472 bool "Enable futex support" if EMBEDDED
473 default y
Ingo Molnar23f78d4a2006-06-27 02:54:53 -0700474 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 help
476 Disabling this option will cause the kernel to be built without
477 support for "fast userspace mutexes". The resulting kernel may not
478 run glibc-based applications correctly.
479
480config EPOLL
481 bool "Enable eventpoll support" if EMBEDDED
482 default y
483 help
484 Disabling this option will cause the kernel to be built without
485 support for epoll family of system calls.
486
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487config SHMEM
488 bool "Use full shmem filesystem" if EMBEDDED
489 default y
490 depends on MMU
491 help
492 The shmem is an internal filesystem used to manage shared memory.
493 It is backed by swap and manages resource limits. It is also exported
494 to userspace as tmpfs if TMPFS is enabled. Disabling this
495 option replaces shmem and tmpfs with the much simpler ramfs code,
496 which may be appropriate on small systems without swap.
497
Christoph Lameterf8891e52006-06-30 01:55:45 -0700498config VM_EVENT_COUNTERS
499 default y
500 bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
501 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -0800502 VM event counters are needed for event counts to be shown.
503 This option allows the disabling of the VM event counters
504 on EMBEDDED systems. /proc/vmstat will only show page counts
505 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -0700506
Christoph Lameter41ecc552007-05-09 02:32:44 -0700507config SLUB_DEBUG
508 default y
509 bool "Enable SLUB debugging support" if EMBEDDED
510 help
511 SLUB has extensive debug support features. Disabling these can
512 result in significant savings in code size. This also disables
513 SLUB sysfs support. /sys/slab will not exist and there will be
514 no support for cache validation etc.
515
Christoph Lameter81819f02007-05-06 14:49:36 -0700516choice
517 prompt "Choose SLAB allocator"
518 default SLAB
519 help
520 This option allows to select a slab allocator.
521
522config SLAB
523 bool "SLAB"
524 help
525 The regular slab allocator that is established and known to work
526 well in all environments. It organizes chache hot objects in
527 per cpu and per node queues. SLAB is the default choice for
528 slab allocator.
529
530config SLUB
531 depends on EXPERIMENTAL && !ARCH_USES_SLAB_PAGE_STRUCT
532 bool "SLUB (Unqueued Allocator)"
533 help
534 SLUB is a slab allocator that minimizes cache line usage
535 instead of managing queues of cached objects (SLAB approach).
536 Per cpu caching is realized using slabs of objects instead
537 of queues of objects. SLUB can use memory efficiently
538 way and has enhanced diagnostics.
539
540config SLOB
541#
542# SLOB cannot support SMP because SLAB_DESTROY_BY_RCU does not work
543# properly.
544#
545 depends on EMBEDDED && !SMP && !SPARSEMEM
546 bool "SLOB (Simple Allocator)"
547 help
548 SLOB replaces the SLAB allocator with a drastically simpler
549 allocator. SLOB is more space efficient that SLAB but does not
550 scale well (single lock for all operations) and is more susceptible
551 to fragmentation. SLOB it is a great choice to reduce
552 memory usage and code size for embedded systems.
553
554endchoice
555
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556endmenu # General setup
557
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700558config RT_MUTEXES
559 boolean
560 select PLIST
561
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562config TINY_SHMEM
563 default !SHMEM
564 bool
565
566config BASE_SMALL
567 int
568 default 0 if BASE_FULL
569 default 1 if !BASE_FULL
570
571menu "Loadable module support"
572
573config MODULES
574 bool "Enable loadable module support"
575 help
576 Kernel modules are small pieces of compiled code which can
577 be inserted in the running kernel, rather than being
578 permanently built into the kernel. You use the "modprobe"
579 tool to add (and sometimes remove) them. If you say Y here,
580 many parts of the kernel can be built as modules (by
581 answering M instead of Y where indicated): this is most
582 useful for infrequently used options which are not required
583 for booting. For more information, see the man pages for
584 modprobe, lsmod, modinfo, insmod and rmmod.
585
586 If you say Y here, you will need to run "make
587 modules_install" to put the modules under /lib/modules/
588 where modprobe can find them (you may need to be root to do
589 this).
590
591 If unsure, say Y.
592
593config MODULE_UNLOAD
594 bool "Module unloading"
595 depends on MODULES
596 help
597 Without this option you will not be able to unload any
598 modules (note that some modules may not be unloadable
599 anyway), which makes your kernel slightly smaller and
600 simpler. If unsure, say Y.
601
602config MODULE_FORCE_UNLOAD
603 bool "Forced module unloading"
604 depends on MODULE_UNLOAD && EXPERIMENTAL
605 help
606 This option allows you to force a module to unload, even if the
607 kernel believes it is unsafe: the kernel will remove the module
608 without waiting for anyone to stop using it (using the -f option to
609 rmmod). This is mainly for kernel developers and desperate users.
610 If unsure, say N.
611
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +0100613 bool "Module versioning support"
614 depends on MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615 help
616 Usually, you have to use modules compiled with your kernel.
617 Saying Y here makes it sometimes possible to use modules
618 compiled for different kernels, by adding enough information
619 to the modules to (hopefully) spot any changes which would
620 make them incompatible with the kernel you are running. If
621 unsure, say N.
622
623config MODULE_SRCVERSION_ALL
624 bool "Source checksum for all modules"
625 depends on MODULES
626 help
627 Modules which contain a MODULE_VERSION get an extra "srcversion"
628 field inserted into their modinfo section, which contains a
629 sum of the source files which made it. This helps maintainers
630 see exactly which source was used to build a module (since
631 others sometimes change the module source without updating
632 the version). With this option, such a "srcversion" field
633 will be created for all modules. If unsure, say N.
634
635config KMOD
636 bool "Automatic kernel module loading"
637 depends on MODULES
638 help
639 Normally when you have selected some parts of the kernel to
640 be created as kernel modules, you must load them (using the
641 "modprobe" command) before you can use them. If you say Y
642 here, some parts of the kernel will be able to load modules
643 automatically: when a part of the kernel needs a module, it
644 runs modprobe with the appropriate arguments, thereby
645 loading the module if it is available. If unsure, say Y.
646
647config STOP_MACHINE
648 bool
649 default y
650 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
651 help
652 Need stop_machine() primitive.
653endmenu
Jens Axboe3a65dfe2005-11-04 08:43:35 +0100654
655menu "Block layer"
656source "block/Kconfig"
657endmenu