blob: 92a1296ba9fa4121dae2c0b468d0105528e530b3 [file] [log] [blame]
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' Giarrussob2670eac2006-10-19 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"
Sam Ravnborg73531902008-05-25 23:03:18 +020016 default "$ARCH_DEFCONFIG"
Roman Zippelface4372006-06-08 22:12:45 -070017 default "arch/$ARCH/defconfig"
18
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -070019config CONSTRUCTORS
20 bool
21 depends on !UML
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -070022
Peter Zijlstrae360adb2010-10-14 14:01:34 +080023config HAVE_IRQ_WORK
24 bool
25
26config IRQ_WORK
27 bool
28 depends on HAVE_IRQ_WORK
29
David Daney1dbdc6f2012-04-19 14:59:57 -070030config BUILDTIME_EXTABLE_SORT
31 bool
32
Al Boldiff0cfc62007-07-31 00:39:23 -070033menu "General setup"
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
35config EXPERIMENTAL
36 bool "Prompt for development and/or incomplete code/drivers"
37 ---help---
38 Some of the various things that Linux supports (such as network
39 drivers, file systems, network protocols, etc.) can be in a state
40 of development where the functionality, stability, or the level of
41 testing is not yet high enough for general use. This is usually
42 known as the "alpha-test" phase among developers. If a feature is
43 currently in alpha-test, then the developers usually discourage
44 uninformed widespread use of this feature by the general public to
45 avoid "Why doesn't this work?" type mail messages. However, active
46 testing and use of these systems is welcomed. Just be aware that it
47 may not meet the normal level of reliability or it may fail to work
48 in some special cases. Detailed bug reports from people familiar
49 with the kernel internals are usually welcomed by the developers
50 (before submitting bug reports, please read the documents
51 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
52 <file:Documentation/BUG-HUNTING>, and
53 <file:Documentation/oops-tracing.txt> in the kernel source).
54
55 This option will also make obsoleted drivers available. These are
56 drivers that have been replaced by something else, and/or are
57 scheduled to be removed in a future kernel release.
58
59 Unless you intend to help test and develop a feature or driver that
60 falls into this category, or you have a situation that requires
61 using these features, you should probably say N here, which will
62 cause the configurator to present you with fewer choices. If
63 you say Y here, you will be offered the choice of using features or
64 drivers that are currently considered to be in the alpha-test phase.
65
Linus Torvalds1da177e2005-04-16 15:20:36 -070066config BROKEN
67 bool
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
69config BROKEN_ON_SMP
70 bool
71 depends on BROKEN || !SMP
72 default y
73
Linus Torvalds1da177e2005-04-16 15:20:36 -070074config INIT_ENV_ARG_LIMIT
75 int
Adrian Bunkdd673bc2006-06-30 01:55:51 -070076 default 32 if !UML
77 default 128 if UML
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 help
Randy Dunlap34ad92c2005-10-30 15:01:46 -080079 Maximum of each of the number of arguments and environment
80 variables passed to init from the kernel command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -070081
Linus Torvalds1da177e2005-04-16 15:20:36 -070082
Roland McGrath84336462009-12-21 16:24:06 -080083config CROSS_COMPILE
84 string "Cross-compiler tool prefix"
85 help
86 Same as running 'make CROSS_COMPILE=prefix-' but stored for
87 default make runs in this kernel build directory. You don't
88 need to set this unless you want the configured kernel build
89 directory to select the cross-compiler automatically.
90
Linus Torvalds1da177e2005-04-16 15:20:36 -070091config LOCALVERSION
92 string "Local version - append to kernel release"
93 help
94 Append an extra string to the end of your kernel version.
95 This will show up when you type uname, for example.
96 The string you set here will be appended after the contents of
97 any files with a filename matching localversion* in your
98 object and source tree, in that order. Your total string can
99 be a maximum of 64 characters.
100
Ryan Andersonaaebf432005-07-31 04:57:49 -0400101config LOCALVERSION_AUTO
102 bool "Automatically append version information to the version string"
103 default y
104 help
105 This will try to automatically determine if the current tree is a
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200106 release tree by looking for git tags that belong to the current
107 top of tree revision.
Ryan Andersonaaebf432005-07-31 04:57:49 -0400108
109 A string of the format -gxxxxxxxx will be added to the localversion
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200110 if a git-based tree is found. The string generated by this will be
Ryan Andersonaaebf432005-07-31 04:57:49 -0400111 appended after any matching localversion* files, and after the value
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200112 set in CONFIG_LOCALVERSION.
Ryan Andersonaaebf432005-07-31 04:57:49 -0400113
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200114 (The actual string used here is the first eight characters produced
115 by running the command:
116
117 $ git rev-parse --verify HEAD
118
119 which is done within the script "scripts/setlocalversion".)
Ryan Andersonaaebf432005-07-31 04:57:49 -0400120
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800121config HAVE_KERNEL_GZIP
122 bool
123
124config HAVE_KERNEL_BZIP2
125 bool
126
127config HAVE_KERNEL_LZMA
128 bool
129
Lasse Collin3ebe1242011-01-12 17:01:23 -0800130config HAVE_KERNEL_XZ
131 bool
132
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800133config HAVE_KERNEL_LZO
134 bool
135
Alain Knaff30d65db2009-01-04 22:46:17 +0100136choice
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800137 prompt "Kernel compression mode"
138 default KERNEL_GZIP
Lasse Collin3ebe1242011-01-12 17:01:23 -0800139 depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800140 help
Alain Knaff30d65db2009-01-04 22:46:17 +0100141 The linux kernel is a kind of self-extracting executable.
142 Several compression algorithms are available, which differ
143 in efficiency, compression and decompression speed.
144 Compression speed is only relevant when building a kernel.
145 Decompression speed is relevant at each boot.
146
147 If you have any problems with bzip2 or lzma compressed
148 kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
149 version of this functionality (bzip2 only), for 2.4, was
150 supplied by Christian Ludwig)
151
152 High compression options are mostly useful for users, who
153 are low on disk space (embedded systems), but for whom ram
154 size matters less.
155
156 If in doubt, select 'gzip'
157
158config KERNEL_GZIP
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800159 bool "Gzip"
160 depends on HAVE_KERNEL_GZIP
161 help
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800162 The old and tried gzip compression. It provides a good balance
163 between compression ratio and decompression speed.
Alain Knaff30d65db2009-01-04 22:46:17 +0100164
165config KERNEL_BZIP2
166 bool "Bzip2"
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800167 depends on HAVE_KERNEL_BZIP2
Alain Knaff30d65db2009-01-04 22:46:17 +0100168 help
169 Its compression ratio and speed is intermediate.
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800170 Decompression speed is slowest among the three. The kernel
171 size is about 10% smaller with bzip2, in comparison to gzip.
172 Bzip2 uses a large amount of memory. For modern kernels you
173 will need at least 8MB RAM or more for booting.
Alain Knaff30d65db2009-01-04 22:46:17 +0100174
175config KERNEL_LZMA
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800176 bool "LZMA"
177 depends on HAVE_KERNEL_LZMA
178 help
179 The most recent compression algorithm.
180 Its ratio is best, decompression speed is between the other
181 two. Compression is slowest. The kernel size is about 33%
182 smaller with LZMA in comparison to gzip.
Alain Knaff30d65db2009-01-04 22:46:17 +0100183
Lasse Collin3ebe1242011-01-12 17:01:23 -0800184config KERNEL_XZ
185 bool "XZ"
186 depends on HAVE_KERNEL_XZ
187 help
188 XZ uses the LZMA2 algorithm and instruction set specific
189 BCJ filters which can improve compression ratio of executable
190 code. The size of the kernel is about 30% smaller with XZ in
191 comparison to gzip. On architectures for which there is a BCJ
192 filter (i386, x86_64, ARM, IA-64, PowerPC, and SPARC), XZ
193 will create a few percent smaller kernel than plain LZMA.
194
195 The speed is about the same as with LZMA: The decompression
196 speed of XZ is better than that of bzip2 but worse than gzip
197 and LZO. Compression is slow.
198
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800199config KERNEL_LZO
200 bool "LZO"
201 depends on HAVE_KERNEL_LZO
202 help
203 Its compression ratio is the poorest among the 4. The kernel
Stephan Sperber681b3042010-07-14 11:23:08 +0200204 size is about 10% bigger than gzip; however its speed
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800205 (both compression and decompression) is the fastest.
206
Alain Knaff30d65db2009-01-04 22:46:17 +0100207endchoice
208
Josh Triplettbd5dc172011-06-15 15:08:28 -0700209config DEFAULT_HOSTNAME
210 string "Default hostname"
211 default "(none)"
212 help
213 This option determines the default system hostname before userspace
214 calls sethostname(2). The kernel traditionally uses "(none)" here,
215 but you may wish to use a different default here to make a minimal
216 system more usable with less configuration.
217
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218config SWAP
219 bool "Support for paging of anonymous memory (swap)"
David Howells93614012006-09-30 20:45:40 +0200220 depends on MMU && BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221 default y
222 help
223 This option allows you to choose whether you want to have support
Jesper Juhl92c35042006-01-15 02:40:08 +0100224 for so called swap devices or swap files in your kernel that are
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 used to provide more virtual memory than the actual RAM present
226 in your computer. If unsure say Y.
227
228config SYSVIPC
229 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 ---help---
231 Inter Process Communication is a suite of library functions and
232 system calls which let processes (running programs) synchronize and
233 exchange information. It is generally considered to be a good thing,
234 and some programs won't run unless you say Y here. In particular, if
235 you want to run the DOS emulator dosemu under Linux (read the
236 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
237 you'll need to say Y here.
238
239 You can find documentation about IPC with "info ipc" and also in
240 section 6.4 of the Linux Programmer's Guide, available from
241 <http://www.tldp.org/guides.html>.
242
Eric W. Biedermana5494dc2007-02-14 00:34:06 -0800243config SYSVIPC_SYSCTL
244 bool
245 depends on SYSVIPC
246 depends on SYSCTL
247 default y
248
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249config POSIX_MQUEUE
250 bool "POSIX Message Queues"
251 depends on NET && EXPERIMENTAL
252 ---help---
253 POSIX variant of message queues is a part of IPC. In POSIX message
254 queues every message has a priority which decides about succession
255 of receiving it by a process. If you want to compile and run
256 programs written e.g. for Solaris with use of its POSIX message
Robert P. J. Dayb0e37652007-05-09 07:25:13 +0200257 queues (functions mq_*) say Y here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258
259 POSIX message queues are visible as a filesystem called 'mqueue'
260 and can be mounted somewhere if you want to do filesystem
261 operations on message queues.
262
263 If unsure, say Y.
264
Serge E. Hallynbdc8e5f2009-04-06 19:01:11 -0700265config POSIX_MQUEUE_SYSCTL
266 bool
267 depends on POSIX_MQUEUE
268 depends on SYSCTL
269 default y
270
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271config BSD_PROCESS_ACCT
272 bool "BSD Process Accounting"
273 help
274 If you say Y here, a user level program will be able to instruct the
275 kernel (via a special system call) to write process accounting
276 information to a file: whenever a process exits, information about
277 that process will be appended to the file by the kernel. The
278 information includes things such as creation time, owning user,
279 command name, memory usage, controlling terminal etc. (the complete
280 list is in the struct acct in <file:include/linux/acct.h>). It is
281 up to the user level program to do useful things with this
282 information. This is generally a good idea, so say Y.
283
284config BSD_PROCESS_ACCT_V3
285 bool "BSD Process Accounting version 3 file format"
286 depends on BSD_PROCESS_ACCT
287 default n
288 help
289 If you say Y here, the process accounting information is written
290 in a new file format that also logs the process IDs of each
291 process and it's parent. Note that this file format is incompatible
292 with previous v0/v1/v2 file formats, so you will need updated tools
293 for processing it. A preliminary version of these tools is available
S.Çağlar Onur37a4c942008-06-18 11:45:13 +0300294 at <http://www.gnu.org/software/acct/>.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295
Aneesh Kumar K.V990d6c22011-01-29 18:43:26 +0530296config FHANDLE
297 bool "open by fhandle syscalls"
298 select EXPORTFS
299 help
300 If you say Y here, a user level program will be able to map
301 file names to handle and then later use the handle for
302 different file system operations. This is useful in implementing
303 userspace file servers, which now track files using handles instead
304 of names. The handle would remain the same even if file names
305 get renamed. Enables open_by_handle_at(2) and name_to_handle_at(2)
306 syscalls.
307
Shailabh Nagarc7572492006-07-14 00:24:40 -0700308config TASKSTATS
309 bool "Export task/process statistics through netlink (EXPERIMENTAL)"
310 depends on NET
311 default n
312 help
313 Export selected statistics for tasks/processes through the
314 generic netlink interface. Unlike BSD process accounting, the
315 statistics are available during the lifetime of tasks/processes as
316 responses to commands. Like BSD accounting, they are sent to user
317 space on task exit.
318
319 Say N if unsure.
320
Shailabh Nagarca74e922006-07-14 00:24:36 -0700321config TASK_DELAY_ACCT
322 bool "Enable per-task delay accounting (EXPERIMENTAL)"
Shailabh Nagar6f449932006-07-14 00:24:41 -0700323 depends on TASKSTATS
Shailabh Nagarca74e922006-07-14 00:24:36 -0700324 help
325 Collect information on time spent by a task waiting for system
326 resources like cpu, synchronous block I/O completion and swapping
327 in pages. Such statistics can help in setting a task's priorities
328 relative to other tasks for cpu, io, rss limits etc.
329
330 Say N if unsure.
331
Alexey Dobriyan18f705f2007-02-10 01:46:44 -0800332config TASK_XACCT
333 bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
334 depends on TASKSTATS
335 help
336 Collect extended task accounting data and send the data
337 to userland for processing over the taskstats interface.
338
339 Say N if unsure.
340
341config TASK_IO_ACCOUNTING
342 bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
343 depends on TASK_XACCT
344 help
345 Collect information on the number of bytes of storage I/O which this
346 task has caused.
347
348 Say N if unsure.
349
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350config AUDIT
351 bool "Auditing support"
Chris Wright804a6a492005-05-11 10:52:45 +0100352 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353 help
354 Enable auditing infrastructure that can be used with another
355 kernel subsystem, such as SELinux (which requires this for
356 logging of avc messages output). Does not do system-call
357 auditing without CONFIG_AUDITSYSCALL.
358
359config AUDITSYSCALL
360 bool "Enable system-call auditing support"
Nathaniel Husted29ef73b2012-01-03 14:23:09 -0500361 depends on AUDIT && (X86 || PPC || S390 || IA64 || UML || SPARC64 || SUPERH || ARM)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362 default y if SECURITY_SELINUX
363 help
364 Enable low-overhead system-call auditing infrastructure that
365 can be used independently or with another kernel subsystem,
Eric Paris67640b62009-12-17 20:12:06 -0500366 such as SELinux.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367
Eric Paris939a67f2009-12-17 20:12:06 -0500368config AUDIT_WATCH
369 def_bool y
370 depends on AUDITSYSCALL
371 select FSNOTIFY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372
Al Viro74c3cbe2007-07-22 08:04:18 -0400373config AUDIT_TREE
374 def_bool y
Eric Paris63c882a2009-05-21 17:02:01 -0400375 depends on AUDITSYSCALL
Eric Paris28a3a7e2009-12-17 20:12:05 -0500376 select FSNOTIFY
Al Viro74c3cbe2007-07-22 08:04:18 -0400377
Eric Paris633b4542012-01-03 14:23:08 -0500378config AUDIT_LOGINUID_IMMUTABLE
379 bool "Make audit loginuid immutable"
380 depends on AUDIT
381 help
Linus Torvaldsf429ee32012-01-17 16:06:51 -0800382 The config option toggles if a task setting its loginuid requires
Eric Paris633b4542012-01-03 14:23:08 -0500383 CAP_SYS_AUDITCONTROL or if that task should require no special permissions
384 but should instead only allow setting its loginuid if it was never
385 previously set. On systems which use systemd or a similar central
386 process to restart login services this should be set to true. On older
387 systems in which an admin would typically have to directly stop and
388 start processes this should be set to false. Setting this to true allows
389 one to drop potentially dangerous capabilites from the login tasks,
390 but may not be backwards compatible with older init systems.
391
Thomas Gleixnerd9817eb2010-09-27 12:45:59 +0000392source "kernel/irq/Kconfig"
393
Mike Travisc903ff82009-01-15 12:28:29 -0800394menu "RCU Subsystem"
395
396choice
397 prompt "RCU Implementation"
Paul E. McKenney31c9a242009-04-02 21:06:25 -0700398 default TREE_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800399
Mike Travisc903ff82009-01-15 12:28:29 -0800400config TREE_RCU
401 bool "Tree-based hierarchical RCU"
Paul E. McKenney687d7a92010-07-21 06:52:40 -0700402 depends on !PREEMPT && SMP
Mike Travisc903ff82009-01-15 12:28:29 -0800403 help
404 This option selects the RCU implementation that is
405 designed for very large SMP system with hundreds or
Paul E. McKenneyc17ef452009-06-23 17:12:47 -0700406 thousands of CPUs. It also scales down nicely to
407 smaller systems.
Mike Travisc903ff82009-01-15 12:28:29 -0800408
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700409config TREE_PREEMPT_RCU
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700410 bool "Preemptible tree-based hierarchical RCU"
Paul E. McKenney8008e122011-06-08 16:31:33 -0700411 depends on PREEMPT && SMP
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700412 help
413 This option selects the RCU implementation that is
414 designed for very large SMP systems with hundreds or
415 thousands of CPUs, but for which real-time response
Paul E. McKenneybbe3eae2009-09-13 09:15:08 -0700416 is also required. It also scales down nicely to
417 smaller systems.
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700418
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -0700419config TINY_RCU
420 bool "UP-only small-memory-footprint RCU"
Paul E. McKenney8008e122011-06-08 16:31:33 -0700421 depends on !PREEMPT && !SMP
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -0700422 help
423 This option selects the RCU implementation that is
424 designed for UP systems from which real-time response
425 is not required. This option greatly reduces the
426 memory footprint of RCU.
427
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700428config TINY_PREEMPT_RCU
429 bool "Preemptible UP-only small-memory-footprint RCU"
Paul E. McKenney8008e122011-06-08 16:31:33 -0700430 depends on PREEMPT && !SMP
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700431 help
432 This option selects the RCU implementation that is designed
433 for real-time UP systems. This option greatly reduces the
434 memory footprint of RCU.
435
Mike Travisc903ff82009-01-15 12:28:29 -0800436endchoice
437
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700438config PREEMPT_RCU
439 def_bool ( TREE_PREEMPT_RCU || TINY_PREEMPT_RCU )
440 help
441 This option enables preemptible-RCU code that is common between
442 the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations.
443
Mike Travisc903ff82009-01-15 12:28:29 -0800444config RCU_FANOUT
445 int "Tree-based hierarchical RCU fanout value"
446 range 2 64 if 64BIT
447 range 2 32 if !64BIT
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700448 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800449 default 64 if 64BIT
450 default 32 if !64BIT
451 help
452 This option controls the fanout of hierarchical implementations
453 of RCU, allowing RCU to work efficiently on machines with
Paul E. McKenney4d87ffa2010-08-04 17:31:12 -0700454 large numbers of CPUs. This value must be at least the fourth
455 root of NR_CPUS, which allows NR_CPUS to be insanely large.
456 The default value of RCU_FANOUT should be used for production
457 systems, but if you are stress-testing the RCU implementation
458 itself, small RCU_FANOUT values allow you to test large-system
459 code paths on small(er) systems.
Mike Travisc903ff82009-01-15 12:28:29 -0800460
461 Select a specific number if testing RCU itself.
462 Take the default if unsure.
463
464config RCU_FANOUT_EXACT
465 bool "Disable tree-based hierarchical RCU auto-balancing"
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700466 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800467 default n
468 help
469 This option forces use of the exact RCU_FANOUT value specified,
470 regardless of imbalances in the hierarchy. This is useful for
471 testing RCU itself, and might one day be useful on systems with
472 strong NUMA behavior.
473
474 Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
475
476 Say N if unsure.
477
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800478config RCU_FAST_NO_HZ
479 bool "Accelerate last non-dyntick-idle CPU's grace periods"
Paul E. McKenneyb807fbf2011-11-03 14:56:12 -0700480 depends on NO_HZ && SMP
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800481 default n
482 help
483 This option causes RCU to attempt to accelerate grace periods
Paul E. McKenneyb807fbf2011-11-03 14:56:12 -0700484 in order to allow CPUs to enter dynticks-idle state more
485 quickly. On the other hand, this option increases the overhead
486 of the dynticks-idle checking, particularly on systems with
487 large numbers of CPUs.
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800488
489 Say Y if energy efficiency is critically important, particularly
490 if you have relatively few CPUs.
491
492 Say N if you are unsure.
493
Mike Travisc903ff82009-01-15 12:28:29 -0800494config TREE_RCU_TRACE
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700495 def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
Mike Travisc903ff82009-01-15 12:28:29 -0800496 select DEBUG_FS
497 help
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700498 This option provides tracing for the TREE_RCU and
499 TREE_PREEMPT_RCU implementations, permitting Makefile to
500 trivially select kernel/rcutree_trace.c.
Mike Travisc903ff82009-01-15 12:28:29 -0800501
Paul E. McKenney24278d12010-09-27 17:25:23 -0700502config RCU_BOOST
503 bool "Enable RCU priority boosting"
Paul E. McKenney27f4d282011-02-07 12:47:15 -0800504 depends on RT_MUTEXES && PREEMPT_RCU
Paul E. McKenney24278d12010-09-27 17:25:23 -0700505 default n
506 help
507 This option boosts the priority of preempted RCU readers that
508 block the current preemptible RCU grace period for too long.
509 This option also prevents heavy loads from blocking RCU
510 callback invocation for all flavors of RCU.
511
512 Say Y here if you are working with real-time apps or heavy loads
513 Say N here if you are unsure.
514
515config RCU_BOOST_PRIO
516 int "Real-time priority to boost RCU readers to"
517 range 1 99
518 depends on RCU_BOOST
519 default 1
520 help
521 This option specifies the real-time priority to which preempted
522 RCU readers are to be boosted. If you are working with CPU-bound
523 real-time applications, you should specify a priority higher then
524 the highest-priority CPU-bound application.
525
526 Specify the real-time priority, or take the default if unsure.
527
528config RCU_BOOST_DELAY
529 int "Milliseconds to delay boosting after RCU grace-period start"
530 range 0 3000
531 depends on RCU_BOOST
532 default 500
533 help
534 This option specifies the time to wait after the beginning of
535 a given grace period before priority-boosting preempted RCU
536 readers blocking that grace period. Note that any RCU reader
537 blocking an expedited RCU grace period is boosted immediately.
538
539 Accept the default if unsure.
540
Mike Travisc903ff82009-01-15 12:28:29 -0800541endmenu # "RCU Subsystem"
542
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700544 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545 ---help---
546 This option enables the complete Linux kernel ".config" file
547 contents to be saved in the kernel. It provides documentation
548 of which kernel options are used in a running kernel or in an
549 on-disk kernel. This information can be extracted from the kernel
550 image file with the script scripts/extract-ikconfig and used as
551 input to rebuild the current kernel or to build another kernel.
552 It can also be extracted from a running kernel by reading
553 /proc/config.gz if enabled (below).
554
555config IKCONFIG_PROC
556 bool "Enable access to .config through /proc/config.gz"
557 depends on IKCONFIG && PROC_FS
558 ---help---
559 This option enables access to the kernel configuration file
560 through /proc/config.gz.
561
Alistair John Strachan794543a2007-05-08 00:31:15 -0700562config LOG_BUF_SHIFT
563 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
564 range 12 21
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700565 default 17
Alistair John Strachan794543a2007-05-08 00:31:15 -0700566 help
567 Select kernel log buffer size as a power of 2.
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700568 Examples:
569 17 => 128 KB
570 16 => 64 KB
571 15 => 32 KB
572 14 => 16 KB
Alistair John Strachan794543a2007-05-08 00:31:15 -0700573 13 => 8 KB
574 12 => 4 KB
575
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800576#
577# Architectures with an unreliable sched_clock() should select this:
578#
579config HAVE_UNSTABLE_SCHED_CLOCK
580 bool
581
Li Zefan23964d22009-01-15 13:50:58 -0800582menuconfig CGROUPS
583 boolean "Control Group support"
Kirill A. Shutemov0dea1162010-03-10 15:22:20 -0800584 depends on EVENTFD
Paul Menageddbcc7e2007-10-18 23:39:30 -0700585 help
Li Zefan23964d22009-01-15 13:50:58 -0800586 This option adds support for grouping sets of processes together, for
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800587 use with process control subsystems such as Cpusets, CFS, memory
588 controls or device isolation.
589 See
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800590 - Documentation/scheduler/sched-design-CFS.txt (CFS)
Li Zefan45ce80f2009-01-15 13:50:59 -0800591 - Documentation/cgroups/ (features for grouping, isolation
592 and resource control)
Paul Menageddbcc7e2007-10-18 23:39:30 -0700593
594 Say N if unsure.
595
Li Zefan23964d22009-01-15 13:50:58 -0800596if CGROUPS
597
Paul Menage006cb992007-10-18 23:39:43 -0700598config CGROUP_DEBUG
599 bool "Example debug cgroup subsystem"
Paul Menage418d7d82008-04-29 01:00:05 -0700600 default n
Paul Menage006cb992007-10-18 23:39:43 -0700601 help
602 This option enables a simple cgroup subsystem that
603 exports useful debugging information about the cgroups
Li Zefan23964d22009-01-15 13:50:58 -0800604 framework.
Paul Menage006cb992007-10-18 23:39:43 -0700605
Li Zefan23964d22009-01-15 13:50:58 -0800606 Say N if unsure.
Paul Menage006cb992007-10-18 23:39:43 -0700607
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700608config CGROUP_FREEZER
Li Zefan23964d22009-01-15 13:50:58 -0800609 bool "Freezer cgroup subsystem"
Li Zefan23964d22009-01-15 13:50:58 -0800610 help
611 Provides a way to freeze and unfreeze all tasks in a
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700612 cgroup.
613
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700614config CGROUP_DEVICE
615 bool "Device controller for cgroups"
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700616 help
617 Provides a cgroup implementing whitelists for devices which
618 a process in the cgroup can mknod or open.
619
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620config CPUSETS
621 bool "Cpuset support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700623 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624 allow dynamically partitioning a system into sets of CPUs and
625 Memory Nodes and assigning tasks to run only within those sets.
626 This is primarily useful on large SMP or NUMA systems.
627
628 Say N if unsure.
629
Li Zefan23964d22009-01-15 13:50:58 -0800630config PROC_PID_CPUSET
631 bool "Include legacy /proc/<pid>/cpuset file"
632 depends on CPUSETS
633 default y
634
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100635config CGROUP_CPUACCT
636 bool "Simple CPU accounting cgroup subsystem"
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100637 help
638 Provides a simple Resource Controller for monitoring the
Li Zefan23964d22009-01-15 13:50:58 -0800639 total CPU consumed by the tasks in a cgroup.
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100640
Pavel Emelianove552b662008-02-07 00:13:49 -0800641config RESOURCE_COUNTERS
642 bool "Resource counters"
643 help
644 This option enables controller independent resource accounting
Li Zefan23964d22009-01-15 13:50:58 -0800645 infrastructure that works with cgroups.
Pavel Emelianove552b662008-02-07 00:13:49 -0800646
Balbir Singh00f0b822008-03-04 14:28:39 -0800647config CGROUP_MEM_RES_CTLR
648 bool "Memory Resource Controller for Control Groups"
Daniel Lezcano79ae9c22010-10-27 15:34:39 -0700649 depends on RESOURCE_COUNTERS
Balbir Singhcf475ad2008-04-29 01:00:16 -0700650 select MM_OWNER
Balbir Singh00f0b822008-03-04 14:28:39 -0800651 help
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700652 Provides a memory resource controller that manages both anonymous
Thadeu Lima de Souza Cascardo21acb9c2009-02-04 10:12:08 +0100653 memory and page cache. (See Documentation/cgroups/memory.txt)
Balbir Singh00f0b822008-03-04 14:28:39 -0800654
655 Note that setting this option increases fixed memory overhead
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700656 associated with each page of memory in the system. By this,
657 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
658 usage tracking struct at boot. Total amount of this is printed out
659 at boot.
Balbir Singh00f0b822008-03-04 14:28:39 -0800660
661 Only enable when you're ok with these trade offs and really
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700662 sure you need the memory resource controller. Even when you enable
663 this, you can set "cgroup_disable=memory" at your boot option to
664 disable memory resource controller and you can avoid overheads.
Li Zefanc9d54092009-01-07 18:07:35 -0800665 (and lose benefits of memory resource controller)
Balbir Singh00f0b822008-03-04 14:28:39 -0800666
Balbir Singhcf475ad2008-04-29 01:00:16 -0700667 This config option also selects MM_OWNER config option, which
668 could in turn add some fork/exit overhead.
669
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800670config CGROUP_MEM_RES_CTLR_SWAP
KAMEZAWA Hiroyuki65e0e812010-08-10 18:02:56 -0700671 bool "Memory Resource Controller Swap Extension"
672 depends on CGROUP_MEM_RES_CTLR && SWAP
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800673 help
674 Add swap management feature to memory resource controller. When you
675 enable this, you can limit mem+swap usage per cgroup. In other words,
676 when you disable this, memory resource controller has no cares to
677 usage of swap...a process can exhaust all of the swap. This extension
678 is useful when you want to avoid exhaustion swap but this itself
679 adds more overheads and consumes memory for remembering information.
680 Especially if you use 32bit system or small memory system, please
681 be careful about enabling this. When memory resource controller
682 is disabled by boot option, this will be automatically disabled and
683 there will be no overhead from this. Even when you set this config=y,
WANG Cong00a66d22011-07-25 17:12:12 -0700684 if boot option "swapaccount=0" is set, swap will not be accounted.
KAMEZAWA Hiroyuki627991a2009-04-02 16:57:47 -0700685 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
686 size is 4096bytes, 512k per 1Gbytes of swap.
Michal Hockoa42c3902010-11-24 12:57:08 -0800687config CGROUP_MEM_RES_CTLR_SWAP_ENABLED
688 bool "Memory Resource Controller Swap Extension enabled by default"
689 depends on CGROUP_MEM_RES_CTLR_SWAP
690 default y
691 help
692 Memory Resource Controller Swap Extension comes with its price in
693 a bigger memory consumption. General purpose distribution kernels
Jim Cromie43d547f2010-12-17 14:32:36 -0700694 which want to enable the feature but keep it disabled by default
Michal Hockoa42c3902010-11-24 12:57:08 -0800695 and let the user enable it by swapaccount boot command line
696 parameter should have this option unselected.
697 For those who want to have the feature enabled by default should
698 select this option (if, for some reason, they need to disable it
WANG Cong00a66d22011-07-25 17:12:12 -0700699 then swapaccount=0 does the trick).
Glauber Costae5671df2011-12-11 21:47:01 +0000700config CGROUP_MEM_RES_CTLR_KMEM
701 bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
702 depends on CGROUP_MEM_RES_CTLR && EXPERIMENTAL
703 default n
704 help
705 The Kernel Memory extension for Memory Resource Controller can limit
706 the amount of memory used by kernel objects in the system. Those are
707 fundamentally different from the entities handled by the standard
708 Memory Controller, which are page-based, and can be swapped. Users of
709 the kmem extension can use it to guarantee that no group of processes
710 will ever exhaust kernel resources alone.
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800711
Stephane Eraniane5d13672011-02-14 11:20:01 +0200712config CGROUP_PERF
713 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
714 depends on PERF_EVENTS && CGROUPS
715 help
716 This option extends the per-cpu mode to restrict monitoring to
Li Zefan2d0f2522011-03-03 14:26:20 +0800717 threads which belong to the cgroup specified and run on the
Stephane Eraniane5d13672011-02-14 11:20:01 +0200718 designated cpu.
719
720 Say N if unsure.
721
Dhaval Giani7c941432010-01-20 13:26:18 +0100722menuconfig CGROUP_SCHED
723 bool "Group CPU scheduler"
Dhaval Giani7c941432010-01-20 13:26:18 +0100724 default n
725 help
726 This feature lets CPU scheduler recognize task groups and control CPU
727 bandwidth allocation to such task groups. It uses cgroups to group
728 tasks.
729
730if CGROUP_SCHED
731config FAIR_GROUP_SCHED
732 bool "Group scheduling for SCHED_OTHER"
733 depends on CGROUP_SCHED
734 default CGROUP_SCHED
735
Paul Turnerab84d312011-07-21 09:43:28 -0700736config CFS_BANDWIDTH
737 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
738 depends on EXPERIMENTAL
739 depends on FAIR_GROUP_SCHED
740 default n
741 help
742 This option allows users to define CPU bandwidth rates (limits) for
743 tasks running within the fair group scheduler. Groups with no limit
744 set are considered to be unconstrained and will run with no
745 restriction.
746 See tip/Documentation/scheduler/sched-bwc.txt for more information.
747
Dhaval Giani7c941432010-01-20 13:26:18 +0100748config RT_GROUP_SCHED
749 bool "Group scheduling for SCHED_RR/FIFO"
750 depends on EXPERIMENTAL
751 depends on CGROUP_SCHED
752 default n
753 help
754 This feature lets you explicitly allocate real CPU bandwidth
Li Zefan32bd7eb2010-03-24 13:17:19 +0800755 to task groups. If enabled, it will also make it impossible to
Dhaval Giani7c941432010-01-20 13:26:18 +0100756 schedule realtime tasks for non-root users until you allocate
757 realtime bandwidth for them.
758 See Documentation/scheduler/sched-rt-group.txt for more information.
759
760endif #CGROUP_SCHED
761
Vivek Goyalafc24d42010-04-26 19:27:56 +0200762config BLK_CGROUP
763 tristate "Block IO controller"
Daniel Lezcano79ae9c22010-10-27 15:34:39 -0700764 depends on BLOCK
Vivek Goyalafc24d42010-04-26 19:27:56 +0200765 default n
766 ---help---
767 Generic block IO controller cgroup interface. This is the common
768 cgroup interface which should be used by various IO controlling
769 policies.
770
771 Currently, CFQ IO scheduler uses it to recognize task groups and
772 control disk bandwidth allocation (proportional time slice allocation)
Vivek Goyale43473b2010-09-15 17:06:35 -0400773 to such task groups. It is also used by bio throttling logic in
774 block layer to implement upper limit in IO rates on a device.
Vivek Goyalafc24d42010-04-26 19:27:56 +0200775
776 This option only enables generic Block IO controller infrastructure.
Vivek Goyale43473b2010-09-15 17:06:35 -0400777 One needs to also enable actual IO controlling logic/policy. For
Michael Witten79e2e752011-01-16 21:43:10 +0000778 enabling proportional weight division of disk bandwidth in CFQ, set
779 CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
Michael Wittenc5e05912011-01-17 00:08:41 +0000780 CONFIG_BLK_DEV_THROTTLING=y.
Vivek Goyalafc24d42010-04-26 19:27:56 +0200781
782 See Documentation/cgroups/blkio-controller.txt for more information.
783
784config DEBUG_BLK_CGROUP
785 bool "Enable Block IO controller debugging"
786 depends on BLK_CGROUP
787 default n
788 ---help---
789 Enable some debugging help. Currently it exports additional stat
790 files in a cgroup which can be useful for debugging.
791
Li Zefan23964d22009-01-15 13:50:58 -0800792endif # CGROUPS
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800793
Cyrill Gorcunov067bce12012-01-12 17:20:49 -0800794config CHECKPOINT_RESTORE
795 bool "Checkpoint/restore support" if EXPERT
796 default n
797 help
798 Enables additional kernel features in a sake of checkpoint/restore.
799 In particular it adds auxiliary prctl codes to setup process text,
800 data and heap segment sizes, and a few additional /proc filesystem
801 entries.
802
803 If unsure, say N here.
804
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700805menuconfig NAMESPACES
David Rientjes6a108a12011-01-20 14:44:16 -0800806 bool "Namespaces support" if EXPERT
807 default !EXPERT
Pavel Emelyanovc5289a62008-02-08 04:18:19 -0800808 help
809 Provides the way to make tasks work with different objects using
810 the same id. For example same IPC id may refer to different objects
811 or same user id or pid may refer to different tasks when used in
812 different namespaces.
813
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700814if NAMESPACES
815
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -0800816config UTS_NS
817 bool "UTS namespace"
Daniel Lezcano17a6d442010-10-27 15:34:37 -0700818 default y
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -0800819 help
820 In this namespace tasks see different info provided with the
821 uname() system call
822
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800823config IPC_NS
824 bool "IPC namespace"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700825 depends on (SYSVIPC || POSIX_MQUEUE)
Daniel Lezcano17a6d442010-10-27 15:34:37 -0700826 default y
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800827 help
828 In this namespace tasks work with IPC ids which correspond to
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700829 different IPC objects in different namespaces.
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800830
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -0800831config USER_NS
832 bool "User namespace (EXPERIMENTAL)"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700833 depends on EXPERIMENTAL
Daniel Lezcano17a6d442010-10-27 15:34:37 -0700834 default y
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -0800835 help
836 This allows containers, i.e. vservers, to use user namespaces
837 to provide different user info for different servers.
838 If unsure, say N.
839
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800840config PID_NS
Daniel Lezcano9bd38c22010-10-27 15:34:37 -0700841 bool "PID Namespaces"
Daniel Lezcano17a6d442010-10-27 15:34:37 -0700842 default y
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800843 help
Heikki Orsila12d2b8f2008-07-06 15:48:02 +0300844 Support process id namespaces. This allows having multiple
Matt LaPlante692105b2009-01-26 11:12:25 +0100845 processes with the same pid as long as they are in different
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800846 pid namespaces. This is a building block of containers.
847
Matt Helsleyd6eb6332009-01-26 12:25:55 -0800848config NET_NS
849 bool "Network namespace"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700850 depends on NET
Daniel Lezcano17a6d442010-10-27 15:34:37 -0700851 default y
Matt Helsleyd6eb6332009-01-26 12:25:55 -0800852 help
853 Allow user space to create what appear to be multiple instances
854 of the network stack.
855
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700856endif # NAMESPACES
857
Mike Galbraith5091faa2010-11-30 14:18:03 +0100858config SCHED_AUTOGROUP
859 bool "Automatic process group scheduling"
860 select EVENTFD
861 select CGROUPS
862 select CGROUP_SCHED
863 select FAIR_GROUP_SCHED
864 help
865 This option optimizes the scheduler for common desktop workloads by
866 automatically creating and populating task groups. This separation
867 of workloads isolates aggressive CPU burners (like build jobs) from
868 desktop applications. Task group autogeneration is currently based
869 upon task session.
870
Daniel Lezcano7af37be2010-10-27 15:34:41 -0700871config MM_OWNER
872 bool
873
874config SYSFS_DEPRECATED
Ferenc Wagner5d6a4ea2011-01-10 19:04:22 +0100875 bool "Enable deprecated sysfs features to support old userspace tools"
Daniel Lezcano7af37be2010-10-27 15:34:41 -0700876 depends on SYSFS
877 default n
878 help
879 This option adds code that switches the layout of the "block" class
880 devices, to not show up in /sys/class/block/, but only in
881 /sys/block/.
882
883 This switch is only active when the sysfs.deprecated=1 boot option is
884 passed or the SYSFS_DEPRECATED_V2 option is set.
885
886 This option allows new kernels to run on old distributions and tools,
887 which might get confused by /sys/class/block/. Since 2007/2008 all
888 major distributions and tools handle this just fine.
889
890 Recent distributions and userspace tools after 2009/2010 depend on
891 the existence of /sys/class/block/, and will not work with this
892 option enabled.
893
894 Only if you are using a new kernel on an old distribution, you might
895 need to say Y here.
896
897config SYSFS_DEPRECATED_V2
Ferenc Wagner5d6a4ea2011-01-10 19:04:22 +0100898 bool "Enable deprecated sysfs features by default"
Daniel Lezcano7af37be2010-10-27 15:34:41 -0700899 default n
900 depends on SYSFS
901 depends on SYSFS_DEPRECATED
902 help
903 Enable deprecated sysfs by default.
904
905 See the CONFIG_SYSFS_DEPRECATED option for more details about this
906 option.
907
908 Only if you are using a new kernel on an old distribution, you might
909 need to say Y here. Even then, odds are you would not need it
910 enabled, you can always pass the boot option if absolutely necessary.
911
912config RELAY
913 bool "Kernel->user space relay support (formerly relayfs)"
914 help
915 This option enables support for relay interface support in
916 certain file systems (such as debugfs).
917 It is designed to provide an efficient mechanism for tools and
918 facilities to relay large amounts of data from kernel space to
919 user space.
920
921 If unsure, say N.
922
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -0800923config BLK_DEV_INITRD
924 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
925 depends on BROKEN || !FRV
926 help
927 The initial RAM filesystem is a ramfs which is loaded by the
928 boot loader (loadlin or lilo) and that is mounted as root
929 before the normal boot procedure. It is typically used to
930 load modules needed to mount the "real" root file system,
931 etc. See <file:Documentation/initrd.txt> for details.
932
933 If RAM disk support (BLK_DEV_RAM) is also included, this
934 also enables initial RAM disk (initrd) support and adds
935 15 Kbytes (more on some other architectures) to the kernel size.
936
937 If unsure say Y.
938
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800939if BLK_DEV_INITRD
940
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200941source "usr/Kconfig"
942
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800943endif
944
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800945config CC_OPTIMIZE_FOR_SIZE
Ingo Molnar96fffeb2008-04-28 01:39:43 +0200946 bool "Optimize for size"
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800947 help
948 Enabling this option will pass "-Os" instead of "-O2" to gcc
949 resulting in a smaller kernel.
950
jkacur775a7222008-07-16 00:31:16 +0200951 If unsure, say Y.
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800952
Randy Dunlap08470622006-09-30 23:28:13 -0700953config SYSCTL
954 bool
955
Randy Dunlapb943c462009-03-10 12:55:46 -0700956config ANON_INODES
957 bool
958
David Rientjes6a108a12011-01-20 14:44:16 -0800959menuconfig EXPERT
960 bool "Configure standard kernel features (expert users)"
Josh Triplettf505c552011-06-05 18:23:58 -0700961 # Unhide debug options, to make the on-by-default options visible
962 select DEBUG_KERNEL
Linus Torvalds1da177e2005-04-16 15:20:36 -0700963 help
964 This option allows certain base kernel options and settings
965 to be disabled or tweaked. This is for specialized
966 environments which can tolerate a "non-standard" kernel.
967 Only use this if you really know what you are doing.
968
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700969config UID16
David Rientjes6a108a12011-01-20 14:44:16 -0800970 bool "Enable 16-bit UID system calls" if EXPERT
David S. Miller09337f52008-04-26 03:17:12 -0700971 depends on ARM || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && COMPAT) || UML || (X86_64 && IA32_EMULATION)
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700972 default y
973 help
974 This enables the legacy 16-bit UID syscall wrappers.
975
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700976config SYSCTL_SYSCALL
David Rientjes6a108a12011-01-20 14:44:16 -0800977 bool "Sysctl syscall support" if EXPERT
Eric W. Biederman26a70342009-11-05 05:26:41 -0800978 depends on PROC_SYSCTL
WANG Congc736de62011-11-02 13:39:25 -0700979 default n
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700980 select SYSCTL
981 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800982 sys_sysctl uses binary paths that have been found challenging
983 to properly maintain and use. The interface in /proc/sys
984 using paths with ascii names is now the primary path to this
985 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700986
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800987 Almost nothing using the binary sysctl interface so if you are
988 trying to save some space it is probably safe to disable this,
989 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700990
WANG Congc736de62011-11-02 13:39:25 -0700991 If unsure say N here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700992
Linus Torvalds1da177e2005-04-16 15:20:36 -0700993config KALLSYMS
David Rientjes6a108a12011-01-20 14:44:16 -0800994 bool "Load all symbols for debugging/ksymoops" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 default y
996 help
997 Say Y here to let the kernel print out symbolic crash information and
998 symbolic stack backtraces. This increases the size of the kernel
999 somewhat, as all symbols have to be loaded into the kernel image.
1000
1001config KALLSYMS_ALL
1002 bool "Include all symbols in kallsyms"
1003 depends on DEBUG_KERNEL && KALLSYMS
1004 help
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001005 Normally kallsyms only contains the symbols of functions for nicer
1006 OOPS messages and backtraces (i.e., symbols from the text and inittext
1007 sections). This is sufficient for most cases. And only in very rare
1008 cases (e.g., when a debugger is used) all symbols are required (e.g.,
1009 names of variables from the data sections, etc).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001010
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001011 This option makes sure that all symbols are loaded into the kernel
1012 image (i.e., symbols from all sections) in cost of increased kernel
1013 size (depending on the kernel configuration, it may be 300KiB or
1014 something like this).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001016 Say N unless you really need all symbols.
Matt Mackalld59745c2005-05-01 08:59:02 -07001017
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -08001018config HOTPLUG
David Rientjes6a108a12011-01-20 14:44:16 -08001019 bool "Support for hot-pluggable devices" if EXPERT
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -08001020 default y
1021 help
1022 This option is provided for the case where no hotplug or uevent
1023 capabilities is wanted by the kernel. You should only consider
1024 disabling this option for embedded systems that do not use modules, a
1025 dynamic /dev tree, or dynamic device discovery. Just say Y.
1026
Matt Mackalld59745c2005-05-01 08:59:02 -07001027config PRINTK
1028 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001029 bool "Enable support for printk" if EXPERT
Matt Mackalld59745c2005-05-01 08:59:02 -07001030 help
1031 This option enables normal printk support. Removing it
1032 eliminates most of the message strings from the kernel image
1033 and makes the kernel more or less silent. As this makes it
1034 very difficult to diagnose system problems, saying N here is
1035 strongly discouraged.
1036
Matt Mackallc8538a72005-05-01 08:59:01 -07001037config BUG
David Rientjes6a108a12011-01-20 14:44:16 -08001038 bool "BUG() support" if EXPERT
Matt Mackallc8538a72005-05-01 08:59:01 -07001039 default y
1040 help
1041 Disabling this option eliminates support for BUG and WARN, reducing
1042 the size of your kernel image and potentially quietly ignoring
1043 numerous fatal conditions. You should only consider disabling this
1044 option for embedded systems with no facilities for reporting errors.
1045 Just say Y.
1046
Matt Mackall708e9a72006-01-08 01:05:25 -08001047config ELF_CORE
1048 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001049 bool "Enable ELF core dumps" if EXPERT
Matt Mackall708e9a72006-01-08 01:05:25 -08001050 help
1051 Enable support for generating core dumps. Disabling saves about 4k.
1052
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001053
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +02001054config PCSPKR_PLATFORM
David Rientjes6a108a12011-01-20 14:44:16 -08001055 bool "Enable PC-Speaker support" if EXPERT
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001056 depends on HAVE_PCSPKR_PLATFORM
Ralf Baechle15f304b2011-06-01 19:04:59 +01001057 select I8253_LOCK
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +02001058 default y
1059 help
1060 This option allows to disable the internal PC-Speaker
1061 support, saving some memory.
1062
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001063config HAVE_PCSPKR_PLATFORM
1064 bool
1065
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066config BASE_FULL
1067 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001068 bool "Enable full-sized data structures for core" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001069 help
1070 Disabling this option reduces the size of miscellaneous core
1071 kernel data structures. This saves memory on small machines,
1072 but may reduce performance.
1073
1074config FUTEX
David Rientjes6a108a12011-01-20 14:44:16 -08001075 bool "Enable futex support" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001076 default y
Ingo Molnar23f78d4a2006-06-27 02:54:53 -07001077 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078 help
1079 Disabling this option will cause the kernel to be built without
1080 support for "fast userspace mutexes". The resulting kernel may not
1081 run glibc-based applications correctly.
1082
1083config EPOLL
David Rientjes6a108a12011-01-20 14:44:16 -08001084 bool "Enable eventpoll support" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001085 default y
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001086 select ANON_INODES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001087 help
1088 Disabling this option will cause the kernel to be built without
1089 support for epoll family of system calls.
1090
Davide Libenzifba2afa2007-05-10 22:23:13 -07001091config SIGNALFD
David Rientjes6a108a12011-01-20 14:44:16 -08001092 bool "Enable signalfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001093 select ANON_INODES
Davide Libenzifba2afa2007-05-10 22:23:13 -07001094 default y
1095 help
1096 Enable the signalfd() system call that allows to receive signals
1097 on a file descriptor.
1098
1099 If unsure, say Y.
1100
Davide Libenzib215e282007-05-10 22:23:16 -07001101config TIMERFD
David Rientjes6a108a12011-01-20 14:44:16 -08001102 bool "Enable timerfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001103 select ANON_INODES
Davide Libenzib215e282007-05-10 22:23:16 -07001104 default y
1105 help
1106 Enable the timerfd() system call that allows to receive timer
1107 events on a file descriptor.
1108
1109 If unsure, say Y.
1110
Davide Libenzie1ad7462007-05-10 22:23:19 -07001111config EVENTFD
David Rientjes6a108a12011-01-20 14:44:16 -08001112 bool "Enable eventfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001113 select ANON_INODES
Davide Libenzie1ad7462007-05-10 22:23:19 -07001114 default y
1115 help
1116 Enable the eventfd() system call that allows to receive both
1117 kernel notification (ie. KAIO) or userspace notifications.
1118
1119 If unsure, say Y.
1120
Linus Torvalds1da177e2005-04-16 15:20:36 -07001121config SHMEM
David Rientjes6a108a12011-01-20 14:44:16 -08001122 bool "Use full shmem filesystem" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001123 default y
1124 depends on MMU
1125 help
1126 The shmem is an internal filesystem used to manage shared memory.
1127 It is backed by swap and manages resource limits. It is also exported
1128 to userspace as tmpfs if TMPFS is enabled. Disabling this
1129 option replaces shmem and tmpfs with the much simpler ramfs code,
1130 which may be appropriate on small systems without swap.
1131
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001132config AIO
David Rientjes6a108a12011-01-20 14:44:16 -08001133 bool "Enable AIO support" if EXPERT
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001134 default y
1135 help
1136 This option enables POSIX asynchronous I/O which may by used
1137 by some high performance threaded applications. Disabling
1138 this option saves about 7k.
1139
Randy Dunlap6befe5f2011-04-26 12:33:21 -07001140config EMBEDDED
1141 bool "Embedded system"
1142 select EXPERT
1143 help
1144 This option should be enabled if compiling the kernel for
1145 an embedded system so certain expert options are available
1146 for configuration.
1147
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001148config HAVE_PERF_EVENTS
Thomas Gleixner0793a612008-12-04 20:12:29 +01001149 bool
Mike Frysinger018df722009-06-12 13:17:43 -04001150 help
1151 See tools/perf/design.txt for details.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001152
Peter Zijlstra906010b2009-09-21 16:08:49 +02001153config PERF_USE_VMALLOC
1154 bool
1155 help
1156 See tools/perf/design.txt for details
1157
Ingo Molnar57c0c152009-09-21 12:20:38 +02001158menu "Kernel Performance Events And Counters"
Thomas Gleixner0793a612008-12-04 20:12:29 +01001159
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001160config PERF_EVENTS
Ingo Molnar57c0c152009-09-21 12:20:38 +02001161 bool "Kernel performance events and counters"
1162 default y if (PROFILING || PERF_COUNTERS)
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001163 depends on HAVE_PERF_EVENTS
Ingo Molnar4c59e462008-12-08 19:38:33 +01001164 select ANON_INODES
Peter Zijlstrae360adb2010-10-14 14:01:34 +08001165 select IRQ_WORK
Thomas Gleixner0793a612008-12-04 20:12:29 +01001166 help
Ingo Molnar57c0c152009-09-21 12:20:38 +02001167 Enable kernel support for various performance events provided
1168 by software and hardware.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001169
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001170 Software events are supported either built-in or via the
Ingo Molnar57c0c152009-09-21 12:20:38 +02001171 use of generic tracepoints.
1172
1173 Most modern CPUs support performance events via performance
1174 counter registers. These registers count the number of certain
Thomas Gleixner0793a612008-12-04 20:12:29 +01001175 types of hw events: such as instructions executed, cachemisses
1176 suffered, or branches mis-predicted - without slowing down the
1177 kernel or applications. These registers can also trigger interrupts
1178 when a threshold number of events have passed - and can thus be
1179 used to profile the code that runs on that CPU.
1180
Ingo Molnar57c0c152009-09-21 12:20:38 +02001181 The Linux Performance Event subsystem provides an abstraction of
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001182 these software and hardware event capabilities, available via a
Ingo Molnar57c0c152009-09-21 12:20:38 +02001183 system call and used by the "perf" utility in tools/perf/. It
Thomas Gleixner0793a612008-12-04 20:12:29 +01001184 provides per task and per CPU counters, and it provides event
1185 capabilities on top of those.
1186
1187 Say Y if unsure.
1188
Ingo Molnar57c0c152009-09-21 12:20:38 +02001189config PERF_COUNTERS
1190 bool "Kernel performance counters (old config option)"
1191 depends on HAVE_PERF_EVENTS
1192 help
1193 This config has been obsoleted by the PERF_EVENTS
1194 config option - please see that one for details.
1195
1196 It has no effect on the kernel whether you enable
1197 it or not, it is a compatibility placeholder.
1198
1199 Say N if unsure.
1200
Peter Zijlstra906010b2009-09-21 16:08:49 +02001201config DEBUG_PERF_USE_VMALLOC
1202 default n
1203 bool "Debug: use vmalloc to back perf mmap() buffers"
1204 depends on PERF_EVENTS && DEBUG_KERNEL
1205 select PERF_USE_VMALLOC
1206 help
1207 Use vmalloc memory to back perf mmap() buffers.
1208
1209 Mostly useful for debugging the vmalloc code on platforms
1210 that don't require it.
1211
1212 Say N if unsure.
1213
Thomas Gleixner0793a612008-12-04 20:12:29 +01001214endmenu
1215
Christoph Lameterf8891e52006-06-30 01:55:45 -07001216config VM_EVENT_COUNTERS
1217 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001218 bool "Enable VM event counters for /proc/vmstat" if EXPERT
Christoph Lameterf8891e52006-06-30 01:55:45 -07001219 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001220 VM event counters are needed for event counts to be shown.
1221 This option allows the disabling of the VM event counters
David Rientjes6a108a12011-01-20 14:44:16 -08001222 on EXPERT systems. /proc/vmstat will only show page counts
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001223 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -07001224
Thomas Petazzoni3d137312008-08-19 10:28:24 +02001225config PCI_QUIRKS
1226 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001227 bool "Enable PCI quirk workarounds" if EXPERT
Geert Uytterhoeven61cfc7e2008-10-22 08:53:25 +02001228 depends on PCI
Thomas Petazzoni3d137312008-08-19 10:28:24 +02001229 help
1230 This enables workarounds for various PCI chipset
1231 bugs/quirks. Disable this only if your target machine is
1232 unaffected by PCI quirks.
1233
Christoph Lameter41ecc552007-05-09 02:32:44 -07001234config SLUB_DEBUG
1235 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001236 bool "Enable SLUB debugging support" if EXPERT
Christoph Lameterf6acb632008-04-29 16:16:06 -07001237 depends on SLUB && SYSFS
Christoph Lameter41ecc552007-05-09 02:32:44 -07001238 help
1239 SLUB has extensive debug support features. Disabling these can
1240 result in significant savings in code size. This also disables
1241 SLUB sysfs support. /sys/slab will not exist and there will be
1242 no support for cache validation etc.
1243
Randy Dunlapb943c462009-03-10 12:55:46 -07001244config COMPAT_BRK
1245 bool "Disable heap randomization"
1246 default y
1247 help
1248 Randomizing heap placement makes heap exploits harder, but it
1249 also breaks ancient binaries (including anything libc5 based).
1250 This option changes the bootup default to heap randomization
Matt LaPlante692105b2009-01-26 11:12:25 +01001251 disabled, and can be overridden at runtime by setting
Randy Dunlapb943c462009-03-10 12:55:46 -07001252 /proc/sys/kernel/randomize_va_space to 2.
1253
1254 On non-ancient distros (post-2000 ones) N is usually a safe choice.
1255
Christoph Lameter81819f02007-05-06 14:49:36 -07001256choice
1257 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -07001258 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001259 help
1260 This option allows to select a slab allocator.
1261
1262config SLAB
1263 bool "SLAB"
1264 help
1265 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -07001266 well in all environments. It organizes cache hot objects in
Simon Arlott02f56212008-11-05 22:18:19 +00001267 per cpu and per node queues.
Christoph Lameter81819f02007-05-06 14:49:36 -07001268
1269config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001270 bool "SLUB (Unqueued Allocator)"
1271 help
1272 SLUB is a slab allocator that minimizes cache line usage
1273 instead of managing queues of cached objects (SLAB approach).
1274 Per cpu caching is realized using slabs of objects instead
1275 of queues of objects. SLUB can use memory efficiently
Simon Arlott02f56212008-11-05 22:18:19 +00001276 and has enhanced diagnostics. SLUB is the default choice for
1277 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -07001278
1279config SLOB
David Rientjes6a108a12011-01-20 14:44:16 -08001280 depends on EXPERT
Christoph Lameter81819f02007-05-06 14:49:36 -07001281 bool "SLOB (Simple Allocator)"
1282 help
Matt Mackall37291452008-02-04 22:29:38 -08001283 SLOB replaces the stock allocator with a drastically simpler
1284 allocator. SLOB is generally more space efficient but
1285 does not perform as well on large systems.
Christoph Lameter81819f02007-05-06 14:49:36 -07001286
1287endchoice
1288
Jie Zhangea637632009-12-14 18:00:02 -08001289config MMAP_ALLOW_UNINITIALIZED
1290 bool "Allow mmapped anonymous memory to be uninitialized"
David Rientjes6a108a12011-01-20 14:44:16 -08001291 depends on EXPERT && !MMU
Jie Zhangea637632009-12-14 18:00:02 -08001292 default n
1293 help
1294 Normally, and according to the Linux spec, anonymous memory obtained
1295 from mmap() has it's contents cleared before it is passed to
1296 userspace. Enabling this config option allows you to request that
1297 mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus
1298 providing a huge performance boost. If this option is not enabled,
1299 then the flag will be ignored.
1300
1301 This is taken advantage of by uClibc's malloc(), and also by
1302 ELF-FDPIC binfmt's brk and stack allocator.
1303
1304 Because of the obvious security issues, this option should only be
1305 enabled on embedded devices where you control what is run in
1306 userspace. Since that isn't generally a problem on no-MMU systems,
1307 it is normally safe to say Y here.
1308
1309 See Documentation/nommu-mmap.txt for more information.
1310
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001311config PROFILING
Robert Richterb309a292010-02-26 15:01:23 +01001312 bool "Profiling support"
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001313 help
1314 Say Y here to enable the extended profiling support mechanisms used
1315 by profilers such as OProfile.
1316
Ingo Molnar5f87f112008-07-23 14:15:22 +02001317#
1318# Place an empty function call at each tracepoint site. Can be
1319# dynamically changed for a probe function.
1320#
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001321config TRACEPOINTS
Ingo Molnar5f87f112008-07-23 14:15:22 +02001322 bool
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001323
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -05001324source "arch/Kconfig"
1325
Linus Torvalds1da177e2005-04-16 15:20:36 -07001326endmenu # General setup
1327
Dmitry Baryshkovee7e5512008-06-29 14:18:46 +04001328config HAVE_GENERIC_DMA_COHERENT
1329 bool
1330 default n
1331
Linus Torvalds158a9622008-01-02 13:04:48 -08001332config SLABINFO
1333 bool
1334 depends on PROC_FS
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001335 depends on SLAB || SLUB_DEBUG
Linus Torvalds158a9622008-01-02 13:04:48 -08001336 default y
1337
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001338config RT_MUTEXES
1339 boolean
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001340
Linus Torvalds1da177e2005-04-16 15:20:36 -07001341config BASE_SMALL
1342 int
1343 default 0 if BASE_FULL
1344 default 1 if !BASE_FULL
1345
Jan Engelhardt66da5732007-07-15 23:39:29 -07001346menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001347 bool "Enable loadable module support"
1348 help
1349 Kernel modules are small pieces of compiled code which can
1350 be inserted in the running kernel, rather than being
1351 permanently built into the kernel. You use the "modprobe"
1352 tool to add (and sometimes remove) them. If you say Y here,
1353 many parts of the kernel can be built as modules (by
1354 answering M instead of Y where indicated): this is most
1355 useful for infrequently used options which are not required
1356 for booting. For more information, see the man pages for
1357 modprobe, lsmod, modinfo, insmod and rmmod.
1358
1359 If you say Y here, you will need to run "make
1360 modules_install" to put the modules under /lib/modules/
1361 where modprobe can find them (you may need to be root to do
1362 this).
1363
1364 If unsure, say Y.
1365
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001366if MODULES
1367
Linus Torvalds826e4502008-05-04 17:04:16 -07001368config MODULE_FORCE_LOAD
1369 bool "Forced module loading"
Linus Torvalds826e4502008-05-04 17:04:16 -07001370 default n
1371 help
Rusty Russell91e37a72008-05-09 16:25:28 +10001372 Allow loading of modules without version information (ie. modprobe
1373 --force). Forced module loading sets the 'F' (forced) taint flag and
1374 is usually a really bad idea.
Linus Torvalds826e4502008-05-04 17:04:16 -07001375
Linus Torvalds1da177e2005-04-16 15:20:36 -07001376config MODULE_UNLOAD
1377 bool "Module unloading"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001378 help
1379 Without this option you will not be able to unload any
1380 modules (note that some modules may not be unloadable
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001381 anyway), which makes your kernel smaller, faster
1382 and simpler. If unsure, say Y.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001383
1384config MODULE_FORCE_UNLOAD
1385 bool "Forced module unloading"
1386 depends on MODULE_UNLOAD && EXPERIMENTAL
1387 help
1388 This option allows you to force a module to unload, even if the
1389 kernel believes it is unsafe: the kernel will remove the module
1390 without waiting for anyone to stop using it (using the -f option to
1391 rmmod). This is mainly for kernel developers and desperate users.
1392 If unsure, say N.
1393
Linus Torvalds1da177e2005-04-16 15:20:36 -07001394config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +01001395 bool "Module versioning support"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001396 help
1397 Usually, you have to use modules compiled with your kernel.
1398 Saying Y here makes it sometimes possible to use modules
1399 compiled for different kernels, by adding enough information
1400 to the modules to (hopefully) spot any changes which would
1401 make them incompatible with the kernel you are running. If
1402 unsure, say N.
1403
1404config MODULE_SRCVERSION_ALL
1405 bool "Source checksum for all modules"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001406 help
1407 Modules which contain a MODULE_VERSION get an extra "srcversion"
1408 field inserted into their modinfo section, which contains a
1409 sum of the source files which made it. This helps maintainers
1410 see exactly which source was used to build a module (since
1411 others sometimes change the module source without updating
1412 the version). With this option, such a "srcversion" field
1413 will be created for all modules. If unsure, say N.
1414
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001415endif # MODULES
1416
Rusty Russell98a79d62008-12-13 21:19:41 +10301417config INIT_ALL_POSSIBLE
1418 bool
1419 help
Rusty Russell5f054e32012-03-29 15:38:31 +10301420 Back when each arch used to define their own cpu_online_mask and
1421 cpu_possible_mask, some of them chose to initialize cpu_possible_mask
Rusty Russell98a79d62008-12-13 21:19:41 +10301422 with all 1s, and others with all 0s. When they were centralised,
1423 it was better to provide this option than to break all the archs
Matt LaPlante692105b2009-01-26 11:12:25 +01001424 and have several arch maintainers pursuing me down dark alleys.
Rusty Russell98a79d62008-12-13 21:19:41 +10301425
Linus Torvalds1da177e2005-04-16 15:20:36 -07001426config STOP_MACHINE
1427 bool
1428 default y
1429 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
1430 help
1431 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001432
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001433source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -07001434
1435config PREEMPT_NOTIFIERS
1436 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +01001437
Steffen Klassert16295be2010-01-06 19:47:10 +11001438config PADATA
1439 depends on SMP
1440 bool
1441
Thomas Gleixner6beb0002009-11-09 15:21:34 +00001442source "kernel/Kconfig.locks"