blob: 85c6870ed476e52c6aa81b3b23aee1a45be2d898 [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
Al Boldiff0cfc62007-07-31 00:39:23 -070030menu "General setup"
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32config EXPERIMENTAL
33 bool "Prompt for development and/or incomplete code/drivers"
34 ---help---
35 Some of the various things that Linux supports (such as network
36 drivers, file systems, network protocols, etc.) can be in a state
37 of development where the functionality, stability, or the level of
38 testing is not yet high enough for general use. This is usually
39 known as the "alpha-test" phase among developers. If a feature is
40 currently in alpha-test, then the developers usually discourage
41 uninformed widespread use of this feature by the general public to
42 avoid "Why doesn't this work?" type mail messages. However, active
43 testing and use of these systems is welcomed. Just be aware that it
44 may not meet the normal level of reliability or it may fail to work
45 in some special cases. Detailed bug reports from people familiar
46 with the kernel internals are usually welcomed by the developers
47 (before submitting bug reports, please read the documents
48 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
49 <file:Documentation/BUG-HUNTING>, and
50 <file:Documentation/oops-tracing.txt> in the kernel source).
51
52 This option will also make obsoleted drivers available. These are
53 drivers that have been replaced by something else, and/or are
54 scheduled to be removed in a future kernel release.
55
56 Unless you intend to help test and develop a feature or driver that
57 falls into this category, or you have a situation that requires
58 using these features, you should probably say N here, which will
59 cause the configurator to present you with fewer choices. If
60 you say Y here, you will be offered the choice of using features or
61 drivers that are currently considered to be in the alpha-test phase.
62
Linus Torvalds1da177e2005-04-16 15:20:36 -070063config BROKEN
64 bool
Linus Torvalds1da177e2005-04-16 15:20:36 -070065
66config BROKEN_ON_SMP
67 bool
68 depends on BROKEN || !SMP
69 default y
70
Linus Torvalds1da177e2005-04-16 15:20:36 -070071config INIT_ENV_ARG_LIMIT
72 int
Adrian Bunkdd673bc2006-06-30 01:55:51 -070073 default 32 if !UML
74 default 128 if UML
Linus Torvalds1da177e2005-04-16 15:20:36 -070075 help
Randy Dunlap34ad92c2005-10-30 15:01:46 -080076 Maximum of each of the number of arguments and environment
77 variables passed to init from the kernel command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
Roland McGrath84336462009-12-21 16:24:06 -080080config CROSS_COMPILE
81 string "Cross-compiler tool prefix"
82 help
83 Same as running 'make CROSS_COMPILE=prefix-' but stored for
84 default make runs in this kernel build directory. You don't
85 need to set this unless you want the configured kernel build
86 directory to select the cross-compiler automatically.
87
Linus Torvalds1da177e2005-04-16 15:20:36 -070088config LOCALVERSION
89 string "Local version - append to kernel release"
90 help
91 Append an extra string to the end of your kernel version.
92 This will show up when you type uname, for example.
93 The string you set here will be appended after the contents of
94 any files with a filename matching localversion* in your
95 object and source tree, in that order. Your total string can
96 be a maximum of 64 characters.
97
Ryan Andersonaaebf432005-07-31 04:57:49 -040098config LOCALVERSION_AUTO
99 bool "Automatically append version information to the version string"
100 default y
101 help
102 This will try to automatically determine if the current tree is a
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200103 release tree by looking for git tags that belong to the current
104 top of tree revision.
Ryan Andersonaaebf432005-07-31 04:57:49 -0400105
106 A string of the format -gxxxxxxxx will be added to the localversion
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200107 if a git-based tree is found. The string generated by this will be
Ryan Andersonaaebf432005-07-31 04:57:49 -0400108 appended after any matching localversion* files, and after the value
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200109 set in CONFIG_LOCALVERSION.
Ryan Andersonaaebf432005-07-31 04:57:49 -0400110
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200111 (The actual string used here is the first eight characters produced
112 by running the command:
113
114 $ git rev-parse --verify HEAD
115
116 which is done within the script "scripts/setlocalversion".)
Ryan Andersonaaebf432005-07-31 04:57:49 -0400117
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800118config HAVE_KERNEL_GZIP
119 bool
120
121config HAVE_KERNEL_BZIP2
122 bool
123
124config HAVE_KERNEL_LZMA
125 bool
126
Lasse Collin3ebe1242011-01-12 17:01:23 -0800127config HAVE_KERNEL_XZ
128 bool
129
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800130config HAVE_KERNEL_LZO
131 bool
132
Alain Knaff30d65db2009-01-04 22:46:17 +0100133choice
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800134 prompt "Kernel compression mode"
135 default KERNEL_GZIP
Lasse Collin3ebe1242011-01-12 17:01:23 -0800136 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 -0800137 help
Alain Knaff30d65db2009-01-04 22:46:17 +0100138 The linux kernel is a kind of self-extracting executable.
139 Several compression algorithms are available, which differ
140 in efficiency, compression and decompression speed.
141 Compression speed is only relevant when building a kernel.
142 Decompression speed is relevant at each boot.
143
144 If you have any problems with bzip2 or lzma compressed
145 kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
146 version of this functionality (bzip2 only), for 2.4, was
147 supplied by Christian Ludwig)
148
149 High compression options are mostly useful for users, who
150 are low on disk space (embedded systems), but for whom ram
151 size matters less.
152
153 If in doubt, select 'gzip'
154
155config KERNEL_GZIP
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800156 bool "Gzip"
157 depends on HAVE_KERNEL_GZIP
158 help
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800159 The old and tried gzip compression. It provides a good balance
160 between compression ratio and decompression speed.
Alain Knaff30d65db2009-01-04 22:46:17 +0100161
162config KERNEL_BZIP2
163 bool "Bzip2"
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800164 depends on HAVE_KERNEL_BZIP2
Alain Knaff30d65db2009-01-04 22:46:17 +0100165 help
166 Its compression ratio and speed is intermediate.
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800167 Decompression speed is slowest among the three. The kernel
168 size is about 10% smaller with bzip2, in comparison to gzip.
169 Bzip2 uses a large amount of memory. For modern kernels you
170 will need at least 8MB RAM or more for booting.
Alain Knaff30d65db2009-01-04 22:46:17 +0100171
172config KERNEL_LZMA
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800173 bool "LZMA"
174 depends on HAVE_KERNEL_LZMA
175 help
176 The most recent compression algorithm.
177 Its ratio is best, decompression speed is between the other
178 two. Compression is slowest. The kernel size is about 33%
179 smaller with LZMA in comparison to gzip.
Alain Knaff30d65db2009-01-04 22:46:17 +0100180
Lasse Collin3ebe1242011-01-12 17:01:23 -0800181config KERNEL_XZ
182 bool "XZ"
183 depends on HAVE_KERNEL_XZ
184 help
185 XZ uses the LZMA2 algorithm and instruction set specific
186 BCJ filters which can improve compression ratio of executable
187 code. The size of the kernel is about 30% smaller with XZ in
188 comparison to gzip. On architectures for which there is a BCJ
189 filter (i386, x86_64, ARM, IA-64, PowerPC, and SPARC), XZ
190 will create a few percent smaller kernel than plain LZMA.
191
192 The speed is about the same as with LZMA: The decompression
193 speed of XZ is better than that of bzip2 but worse than gzip
194 and LZO. Compression is slow.
195
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800196config KERNEL_LZO
197 bool "LZO"
198 depends on HAVE_KERNEL_LZO
199 help
200 Its compression ratio is the poorest among the 4. The kernel
Stephan Sperber681b3042010-07-14 11:23:08 +0200201 size is about 10% bigger than gzip; however its speed
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800202 (both compression and decompression) is the fastest.
203
Alain Knaff30d65db2009-01-04 22:46:17 +0100204endchoice
205
Josh Triplettbd5dc172011-06-15 15:08:28 -0700206config DEFAULT_HOSTNAME
207 string "Default hostname"
208 default "(none)"
209 help
210 This option determines the default system hostname before userspace
211 calls sethostname(2). The kernel traditionally uses "(none)" here,
212 but you may wish to use a different default here to make a minimal
213 system more usable with less configuration.
214
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215config SWAP
216 bool "Support for paging of anonymous memory (swap)"
David Howells93614012006-09-30 20:45:40 +0200217 depends on MMU && BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 default y
219 help
220 This option allows you to choose whether you want to have support
Jesper Juhl92c35042006-01-15 02:40:08 +0100221 for so called swap devices or swap files in your kernel that are
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 used to provide more virtual memory than the actual RAM present
223 in your computer. If unsure say Y.
224
225config SYSVIPC
226 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 ---help---
228 Inter Process Communication is a suite of library functions and
229 system calls which let processes (running programs) synchronize and
230 exchange information. It is generally considered to be a good thing,
231 and some programs won't run unless you say Y here. In particular, if
232 you want to run the DOS emulator dosemu under Linux (read the
233 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
234 you'll need to say Y here.
235
236 You can find documentation about IPC with "info ipc" and also in
237 section 6.4 of the Linux Programmer's Guide, available from
238 <http://www.tldp.org/guides.html>.
239
Eric W. Biedermana5494dc2007-02-14 00:34:06 -0800240config SYSVIPC_SYSCTL
241 bool
242 depends on SYSVIPC
243 depends on SYSCTL
244 default y
245
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246config POSIX_MQUEUE
247 bool "POSIX Message Queues"
248 depends on NET && EXPERIMENTAL
249 ---help---
250 POSIX variant of message queues is a part of IPC. In POSIX message
251 queues every message has a priority which decides about succession
252 of receiving it by a process. If you want to compile and run
253 programs written e.g. for Solaris with use of its POSIX message
Robert P. J. Dayb0e37652007-05-09 07:25:13 +0200254 queues (functions mq_*) say Y here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255
256 POSIX message queues are visible as a filesystem called 'mqueue'
257 and can be mounted somewhere if you want to do filesystem
258 operations on message queues.
259
260 If unsure, say Y.
261
Serge E. Hallynbdc8e5f2009-04-06 19:01:11 -0700262config POSIX_MQUEUE_SYSCTL
263 bool
264 depends on POSIX_MQUEUE
265 depends on SYSCTL
266 default y
267
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268config BSD_PROCESS_ACCT
269 bool "BSD Process Accounting"
270 help
271 If you say Y here, a user level program will be able to instruct the
272 kernel (via a special system call) to write process accounting
273 information to a file: whenever a process exits, information about
274 that process will be appended to the file by the kernel. The
275 information includes things such as creation time, owning user,
276 command name, memory usage, controlling terminal etc. (the complete
277 list is in the struct acct in <file:include/linux/acct.h>). It is
278 up to the user level program to do useful things with this
279 information. This is generally a good idea, so say Y.
280
281config BSD_PROCESS_ACCT_V3
282 bool "BSD Process Accounting version 3 file format"
283 depends on BSD_PROCESS_ACCT
284 default n
285 help
286 If you say Y here, the process accounting information is written
287 in a new file format that also logs the process IDs of each
288 process and it's parent. Note that this file format is incompatible
289 with previous v0/v1/v2 file formats, so you will need updated tools
290 for processing it. A preliminary version of these tools is available
S.Çağlar Onur37a4c942008-06-18 11:45:13 +0300291 at <http://www.gnu.org/software/acct/>.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292
Aneesh Kumar K.V990d6c22011-01-29 18:43:26 +0530293config FHANDLE
294 bool "open by fhandle syscalls"
295 select EXPORTFS
296 help
297 If you say Y here, a user level program will be able to map
298 file names to handle and then later use the handle for
299 different file system operations. This is useful in implementing
300 userspace file servers, which now track files using handles instead
301 of names. The handle would remain the same even if file names
302 get renamed. Enables open_by_handle_at(2) and name_to_handle_at(2)
303 syscalls.
304
Shailabh Nagarc7572492006-07-14 00:24:40 -0700305config TASKSTATS
306 bool "Export task/process statistics through netlink (EXPERIMENTAL)"
307 depends on NET
308 default n
309 help
310 Export selected statistics for tasks/processes through the
311 generic netlink interface. Unlike BSD process accounting, the
312 statistics are available during the lifetime of tasks/processes as
313 responses to commands. Like BSD accounting, they are sent to user
314 space on task exit.
315
316 Say N if unsure.
317
Shailabh Nagarca74e922006-07-14 00:24:36 -0700318config TASK_DELAY_ACCT
319 bool "Enable per-task delay accounting (EXPERIMENTAL)"
Shailabh Nagar6f449932006-07-14 00:24:41 -0700320 depends on TASKSTATS
Shailabh Nagarca74e922006-07-14 00:24:36 -0700321 help
322 Collect information on time spent by a task waiting for system
323 resources like cpu, synchronous block I/O completion and swapping
324 in pages. Such statistics can help in setting a task's priorities
325 relative to other tasks for cpu, io, rss limits etc.
326
327 Say N if unsure.
328
Alexey Dobriyan18f705f2007-02-10 01:46:44 -0800329config TASK_XACCT
330 bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
331 depends on TASKSTATS
332 help
333 Collect extended task accounting data and send the data
334 to userland for processing over the taskstats interface.
335
336 Say N if unsure.
337
338config TASK_IO_ACCOUNTING
339 bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
340 depends on TASK_XACCT
341 help
342 Collect information on the number of bytes of storage I/O which this
343 task has caused.
344
345 Say N if unsure.
346
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347config AUDIT
348 bool "Auditing support"
Chris Wright804a6a492005-05-11 10:52:45 +0100349 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 help
351 Enable auditing infrastructure that can be used with another
352 kernel subsystem, such as SELinux (which requires this for
353 logging of avc messages output). Does not do system-call
354 auditing without CONFIG_AUDITSYSCALL.
355
356config AUDITSYSCALL
357 bool "Enable system-call auditing support"
Nathaniel Husted29ef73b2012-01-03 14:23:09 -0500358 depends on AUDIT && (X86 || PPC || S390 || IA64 || UML || SPARC64 || SUPERH || ARM)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 default y if SECURITY_SELINUX
360 help
361 Enable low-overhead system-call auditing infrastructure that
362 can be used independently or with another kernel subsystem,
Eric Paris67640b62009-12-17 20:12:06 -0500363 such as SELinux.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364
Eric Paris939a67f2009-12-17 20:12:06 -0500365config AUDIT_WATCH
366 def_bool y
367 depends on AUDITSYSCALL
368 select FSNOTIFY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369
Al Viro74c3cbe2007-07-22 08:04:18 -0400370config AUDIT_TREE
371 def_bool y
Eric Paris63c882a2009-05-21 17:02:01 -0400372 depends on AUDITSYSCALL
Eric Paris28a3a7e2009-12-17 20:12:05 -0500373 select FSNOTIFY
Al Viro74c3cbe2007-07-22 08:04:18 -0400374
Eric Paris633b4542012-01-03 14:23:08 -0500375config AUDIT_LOGINUID_IMMUTABLE
376 bool "Make audit loginuid immutable"
377 depends on AUDIT
378 help
Linus Torvaldsf429ee32012-01-17 16:06:51 -0800379 The config option toggles if a task setting its loginuid requires
Eric Paris633b4542012-01-03 14:23:08 -0500380 CAP_SYS_AUDITCONTROL or if that task should require no special permissions
381 but should instead only allow setting its loginuid if it was never
382 previously set. On systems which use systemd or a similar central
383 process to restart login services this should be set to true. On older
384 systems in which an admin would typically have to directly stop and
385 start processes this should be set to false. Setting this to true allows
386 one to drop potentially dangerous capabilites from the login tasks,
387 but may not be backwards compatible with older init systems.
388
Thomas Gleixnerd9817eb2010-09-27 12:45:59 +0000389source "kernel/irq/Kconfig"
390
Mike Travisc903ff82009-01-15 12:28:29 -0800391menu "RCU Subsystem"
392
393choice
394 prompt "RCU Implementation"
Paul E. McKenney31c9a242009-04-02 21:06:25 -0700395 default TREE_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800396
Mike Travisc903ff82009-01-15 12:28:29 -0800397config TREE_RCU
398 bool "Tree-based hierarchical RCU"
Paul E. McKenney687d7a92010-07-21 06:52:40 -0700399 depends on !PREEMPT && SMP
Mike Travisc903ff82009-01-15 12:28:29 -0800400 help
401 This option selects the RCU implementation that is
402 designed for very large SMP system with hundreds or
Paul E. McKenneyc17ef452009-06-23 17:12:47 -0700403 thousands of CPUs. It also scales down nicely to
404 smaller systems.
Mike Travisc903ff82009-01-15 12:28:29 -0800405
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700406config TREE_PREEMPT_RCU
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700407 bool "Preemptible tree-based hierarchical RCU"
Paul E. McKenney8008e122011-06-08 16:31:33 -0700408 depends on PREEMPT && SMP
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700409 help
410 This option selects the RCU implementation that is
411 designed for very large SMP systems with hundreds or
412 thousands of CPUs, but for which real-time response
Paul E. McKenneybbe3eae2009-09-13 09:15:08 -0700413 is also required. It also scales down nicely to
414 smaller systems.
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700415
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -0700416config TINY_RCU
417 bool "UP-only small-memory-footprint RCU"
Paul E. McKenney8008e122011-06-08 16:31:33 -0700418 depends on !PREEMPT && !SMP
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -0700419 help
420 This option selects the RCU implementation that is
421 designed for UP systems from which real-time response
422 is not required. This option greatly reduces the
423 memory footprint of RCU.
424
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700425config TINY_PREEMPT_RCU
426 bool "Preemptible UP-only small-memory-footprint RCU"
Paul E. McKenney8008e122011-06-08 16:31:33 -0700427 depends on PREEMPT && !SMP
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700428 help
429 This option selects the RCU implementation that is designed
430 for real-time UP systems. This option greatly reduces the
431 memory footprint of RCU.
432
Mike Travisc903ff82009-01-15 12:28:29 -0800433endchoice
434
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700435config PREEMPT_RCU
436 def_bool ( TREE_PREEMPT_RCU || TINY_PREEMPT_RCU )
437 help
438 This option enables preemptible-RCU code that is common between
439 the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations.
440
Mike Travisc903ff82009-01-15 12:28:29 -0800441config RCU_FANOUT
442 int "Tree-based hierarchical RCU fanout value"
443 range 2 64 if 64BIT
444 range 2 32 if !64BIT
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700445 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800446 default 64 if 64BIT
447 default 32 if !64BIT
448 help
449 This option controls the fanout of hierarchical implementations
450 of RCU, allowing RCU to work efficiently on machines with
Paul E. McKenney4d87ffa2010-08-04 17:31:12 -0700451 large numbers of CPUs. This value must be at least the fourth
452 root of NR_CPUS, which allows NR_CPUS to be insanely large.
453 The default value of RCU_FANOUT should be used for production
454 systems, but if you are stress-testing the RCU implementation
455 itself, small RCU_FANOUT values allow you to test large-system
456 code paths on small(er) systems.
Mike Travisc903ff82009-01-15 12:28:29 -0800457
458 Select a specific number if testing RCU itself.
459 Take the default if unsure.
460
461config RCU_FANOUT_EXACT
462 bool "Disable tree-based hierarchical RCU auto-balancing"
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700463 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800464 default n
465 help
466 This option forces use of the exact RCU_FANOUT value specified,
467 regardless of imbalances in the hierarchy. This is useful for
468 testing RCU itself, and might one day be useful on systems with
469 strong NUMA behavior.
470
471 Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
472
473 Say N if unsure.
474
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800475config RCU_FAST_NO_HZ
476 bool "Accelerate last non-dyntick-idle CPU's grace periods"
Paul E. McKenneyb807fbf2011-11-03 14:56:12 -0700477 depends on NO_HZ && SMP
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800478 default n
479 help
480 This option causes RCU to attempt to accelerate grace periods
Paul E. McKenneyb807fbf2011-11-03 14:56:12 -0700481 in order to allow CPUs to enter dynticks-idle state more
482 quickly. On the other hand, this option increases the overhead
483 of the dynticks-idle checking, particularly on systems with
484 large numbers of CPUs.
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800485
486 Say Y if energy efficiency is critically important, particularly
487 if you have relatively few CPUs.
488
489 Say N if you are unsure.
490
Mike Travisc903ff82009-01-15 12:28:29 -0800491config TREE_RCU_TRACE
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700492 def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
Mike Travisc903ff82009-01-15 12:28:29 -0800493 select DEBUG_FS
494 help
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700495 This option provides tracing for the TREE_RCU and
496 TREE_PREEMPT_RCU implementations, permitting Makefile to
497 trivially select kernel/rcutree_trace.c.
Mike Travisc903ff82009-01-15 12:28:29 -0800498
Paul E. McKenney24278d12010-09-27 17:25:23 -0700499config RCU_BOOST
500 bool "Enable RCU priority boosting"
Paul E. McKenney27f4d282011-02-07 12:47:15 -0800501 depends on RT_MUTEXES && PREEMPT_RCU
Paul E. McKenney24278d12010-09-27 17:25:23 -0700502 default n
503 help
504 This option boosts the priority of preempted RCU readers that
505 block the current preemptible RCU grace period for too long.
506 This option also prevents heavy loads from blocking RCU
507 callback invocation for all flavors of RCU.
508
509 Say Y here if you are working with real-time apps or heavy loads
510 Say N here if you are unsure.
511
512config RCU_BOOST_PRIO
513 int "Real-time priority to boost RCU readers to"
514 range 1 99
515 depends on RCU_BOOST
516 default 1
517 help
Paul E. McKenneyc9336642012-04-18 16:20:18 -0700518 This option specifies the real-time priority to which long-term
519 preempted RCU readers are to be boosted. If you are working
520 with a real-time application that has one or more CPU-bound
521 threads running at a real-time priority level, you should set
522 RCU_BOOST_PRIO to a priority higher then the highest-priority
523 real-time CPU-bound thread. The default RCU_BOOST_PRIO value
524 of 1 is appropriate in the common case, which is real-time
525 applications that do not have any CPU-bound threads.
526
527 Some real-time applications might not have a single real-time
528 thread that saturates a given CPU, but instead might have
529 multiple real-time threads that, taken together, fully utilize
530 that CPU. In this case, you should set RCU_BOOST_PRIO to
531 a priority higher than the lowest-priority thread that is
532 conspiring to prevent the CPU from running any non-real-time
533 tasks. For example, if one thread at priority 10 and another
534 thread at priority 5 are between themselves fully consuming
535 the CPU time on a given CPU, then RCU_BOOST_PRIO should be
536 set to priority 6 or higher.
Paul E. McKenney24278d12010-09-27 17:25:23 -0700537
538 Specify the real-time priority, or take the default if unsure.
539
540config RCU_BOOST_DELAY
541 int "Milliseconds to delay boosting after RCU grace-period start"
542 range 0 3000
543 depends on RCU_BOOST
544 default 500
545 help
546 This option specifies the time to wait after the beginning of
547 a given grace period before priority-boosting preempted RCU
548 readers blocking that grace period. Note that any RCU reader
549 blocking an expedited RCU grace period is boosted immediately.
550
551 Accept the default if unsure.
552
Mike Travisc903ff82009-01-15 12:28:29 -0800553endmenu # "RCU Subsystem"
554
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700556 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 ---help---
558 This option enables the complete Linux kernel ".config" file
559 contents to be saved in the kernel. It provides documentation
560 of which kernel options are used in a running kernel or in an
561 on-disk kernel. This information can be extracted from the kernel
562 image file with the script scripts/extract-ikconfig and used as
563 input to rebuild the current kernel or to build another kernel.
564 It can also be extracted from a running kernel by reading
565 /proc/config.gz if enabled (below).
566
567config IKCONFIG_PROC
568 bool "Enable access to .config through /proc/config.gz"
569 depends on IKCONFIG && PROC_FS
570 ---help---
571 This option enables access to the kernel configuration file
572 through /proc/config.gz.
573
Alistair John Strachan794543a2007-05-08 00:31:15 -0700574config LOG_BUF_SHIFT
575 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
576 range 12 21
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700577 default 17
Alistair John Strachan794543a2007-05-08 00:31:15 -0700578 help
579 Select kernel log buffer size as a power of 2.
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700580 Examples:
581 17 => 128 KB
582 16 => 64 KB
583 15 => 32 KB
584 14 => 16 KB
Alistair John Strachan794543a2007-05-08 00:31:15 -0700585 13 => 8 KB
586 12 => 4 KB
587
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800588#
589# Architectures with an unreliable sched_clock() should select this:
590#
591config HAVE_UNSTABLE_SCHED_CLOCK
592 bool
593
Li Zefan23964d22009-01-15 13:50:58 -0800594menuconfig CGROUPS
595 boolean "Control Group support"
Kirill A. Shutemov0dea1162010-03-10 15:22:20 -0800596 depends on EVENTFD
Paul Menageddbcc7e2007-10-18 23:39:30 -0700597 help
Li Zefan23964d22009-01-15 13:50:58 -0800598 This option adds support for grouping sets of processes together, for
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800599 use with process control subsystems such as Cpusets, CFS, memory
600 controls or device isolation.
601 See
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800602 - Documentation/scheduler/sched-design-CFS.txt (CFS)
Li Zefan45ce80f2009-01-15 13:50:59 -0800603 - Documentation/cgroups/ (features for grouping, isolation
604 and resource control)
Paul Menageddbcc7e2007-10-18 23:39:30 -0700605
606 Say N if unsure.
607
Li Zefan23964d22009-01-15 13:50:58 -0800608if CGROUPS
609
Paul Menage006cb992007-10-18 23:39:43 -0700610config CGROUP_DEBUG
611 bool "Example debug cgroup subsystem"
Paul Menage418d7d82008-04-29 01:00:05 -0700612 default n
Paul Menage006cb992007-10-18 23:39:43 -0700613 help
614 This option enables a simple cgroup subsystem that
615 exports useful debugging information about the cgroups
Li Zefan23964d22009-01-15 13:50:58 -0800616 framework.
Paul Menage006cb992007-10-18 23:39:43 -0700617
Li Zefan23964d22009-01-15 13:50:58 -0800618 Say N if unsure.
Paul Menage006cb992007-10-18 23:39:43 -0700619
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700620config CGROUP_FREEZER
Li Zefan23964d22009-01-15 13:50:58 -0800621 bool "Freezer cgroup subsystem"
Li Zefan23964d22009-01-15 13:50:58 -0800622 help
623 Provides a way to freeze and unfreeze all tasks in a
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700624 cgroup.
625
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700626config CGROUP_DEVICE
627 bool "Device controller for cgroups"
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700628 help
629 Provides a cgroup implementing whitelists for devices which
630 a process in the cgroup can mknod or open.
631
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632config CPUSETS
633 bool "Cpuset support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700635 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636 allow dynamically partitioning a system into sets of CPUs and
637 Memory Nodes and assigning tasks to run only within those sets.
638 This is primarily useful on large SMP or NUMA systems.
639
640 Say N if unsure.
641
Li Zefan23964d22009-01-15 13:50:58 -0800642config PROC_PID_CPUSET
643 bool "Include legacy /proc/<pid>/cpuset file"
644 depends on CPUSETS
645 default y
646
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100647config CGROUP_CPUACCT
648 bool "Simple CPU accounting cgroup subsystem"
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100649 help
650 Provides a simple Resource Controller for monitoring the
Li Zefan23964d22009-01-15 13:50:58 -0800651 total CPU consumed by the tasks in a cgroup.
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100652
Pavel Emelianove552b662008-02-07 00:13:49 -0800653config RESOURCE_COUNTERS
654 bool "Resource counters"
655 help
656 This option enables controller independent resource accounting
Li Zefan23964d22009-01-15 13:50:58 -0800657 infrastructure that works with cgroups.
Pavel Emelianove552b662008-02-07 00:13:49 -0800658
Balbir Singh00f0b822008-03-04 14:28:39 -0800659config CGROUP_MEM_RES_CTLR
660 bool "Memory Resource Controller for Control Groups"
Daniel Lezcano79ae9c22010-10-27 15:34:39 -0700661 depends on RESOURCE_COUNTERS
Balbir Singhcf475ad2008-04-29 01:00:16 -0700662 select MM_OWNER
Balbir Singh00f0b822008-03-04 14:28:39 -0800663 help
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700664 Provides a memory resource controller that manages both anonymous
Thadeu Lima de Souza Cascardo21acb9c2009-02-04 10:12:08 +0100665 memory and page cache. (See Documentation/cgroups/memory.txt)
Balbir Singh00f0b822008-03-04 14:28:39 -0800666
667 Note that setting this option increases fixed memory overhead
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700668 associated with each page of memory in the system. By this,
669 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
670 usage tracking struct at boot. Total amount of this is printed out
671 at boot.
Balbir Singh00f0b822008-03-04 14:28:39 -0800672
673 Only enable when you're ok with these trade offs and really
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700674 sure you need the memory resource controller. Even when you enable
675 this, you can set "cgroup_disable=memory" at your boot option to
676 disable memory resource controller and you can avoid overheads.
Li Zefanc9d54092009-01-07 18:07:35 -0800677 (and lose benefits of memory resource controller)
Balbir Singh00f0b822008-03-04 14:28:39 -0800678
Balbir Singhcf475ad2008-04-29 01:00:16 -0700679 This config option also selects MM_OWNER config option, which
680 could in turn add some fork/exit overhead.
681
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800682config CGROUP_MEM_RES_CTLR_SWAP
KAMEZAWA Hiroyuki65e0e812010-08-10 18:02:56 -0700683 bool "Memory Resource Controller Swap Extension"
684 depends on CGROUP_MEM_RES_CTLR && SWAP
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800685 help
686 Add swap management feature to memory resource controller. When you
687 enable this, you can limit mem+swap usage per cgroup. In other words,
688 when you disable this, memory resource controller has no cares to
689 usage of swap...a process can exhaust all of the swap. This extension
690 is useful when you want to avoid exhaustion swap but this itself
691 adds more overheads and consumes memory for remembering information.
692 Especially if you use 32bit system or small memory system, please
693 be careful about enabling this. When memory resource controller
694 is disabled by boot option, this will be automatically disabled and
695 there will be no overhead from this. Even when you set this config=y,
WANG Cong00a66d22011-07-25 17:12:12 -0700696 if boot option "swapaccount=0" is set, swap will not be accounted.
KAMEZAWA Hiroyuki627991a2009-04-02 16:57:47 -0700697 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
698 size is 4096bytes, 512k per 1Gbytes of swap.
Michal Hockoa42c3902010-11-24 12:57:08 -0800699config CGROUP_MEM_RES_CTLR_SWAP_ENABLED
700 bool "Memory Resource Controller Swap Extension enabled by default"
701 depends on CGROUP_MEM_RES_CTLR_SWAP
702 default y
703 help
704 Memory Resource Controller Swap Extension comes with its price in
705 a bigger memory consumption. General purpose distribution kernels
Jim Cromie43d547f2010-12-17 14:32:36 -0700706 which want to enable the feature but keep it disabled by default
Michal Hockoa42c3902010-11-24 12:57:08 -0800707 and let the user enable it by swapaccount boot command line
708 parameter should have this option unselected.
709 For those who want to have the feature enabled by default should
710 select this option (if, for some reason, they need to disable it
WANG Cong00a66d22011-07-25 17:12:12 -0700711 then swapaccount=0 does the trick).
Glauber Costae5671df2011-12-11 21:47:01 +0000712config CGROUP_MEM_RES_CTLR_KMEM
713 bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
714 depends on CGROUP_MEM_RES_CTLR && EXPERIMENTAL
715 default n
716 help
717 The Kernel Memory extension for Memory Resource Controller can limit
718 the amount of memory used by kernel objects in the system. Those are
719 fundamentally different from the entities handled by the standard
720 Memory Controller, which are page-based, and can be swapped. Users of
721 the kmem extension can use it to guarantee that no group of processes
722 will ever exhaust kernel resources alone.
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800723
Stephane Eraniane5d13672011-02-14 11:20:01 +0200724config CGROUP_PERF
725 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
726 depends on PERF_EVENTS && CGROUPS
727 help
728 This option extends the per-cpu mode to restrict monitoring to
Li Zefan2d0f2522011-03-03 14:26:20 +0800729 threads which belong to the cgroup specified and run on the
Stephane Eraniane5d13672011-02-14 11:20:01 +0200730 designated cpu.
731
732 Say N if unsure.
733
Dhaval Giani7c941432010-01-20 13:26:18 +0100734menuconfig CGROUP_SCHED
735 bool "Group CPU scheduler"
Dhaval Giani7c941432010-01-20 13:26:18 +0100736 default n
737 help
738 This feature lets CPU scheduler recognize task groups and control CPU
739 bandwidth allocation to such task groups. It uses cgroups to group
740 tasks.
741
742if CGROUP_SCHED
743config FAIR_GROUP_SCHED
744 bool "Group scheduling for SCHED_OTHER"
745 depends on CGROUP_SCHED
746 default CGROUP_SCHED
747
Paul Turnerab84d312011-07-21 09:43:28 -0700748config CFS_BANDWIDTH
749 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
750 depends on EXPERIMENTAL
751 depends on FAIR_GROUP_SCHED
752 default n
753 help
754 This option allows users to define CPU bandwidth rates (limits) for
755 tasks running within the fair group scheduler. Groups with no limit
756 set are considered to be unconstrained and will run with no
757 restriction.
758 See tip/Documentation/scheduler/sched-bwc.txt for more information.
759
Dhaval Giani7c941432010-01-20 13:26:18 +0100760config RT_GROUP_SCHED
761 bool "Group scheduling for SCHED_RR/FIFO"
762 depends on EXPERIMENTAL
763 depends on CGROUP_SCHED
764 default n
765 help
766 This feature lets you explicitly allocate real CPU bandwidth
Li Zefan32bd7eb2010-03-24 13:17:19 +0800767 to task groups. If enabled, it will also make it impossible to
Dhaval Giani7c941432010-01-20 13:26:18 +0100768 schedule realtime tasks for non-root users until you allocate
769 realtime bandwidth for them.
770 See Documentation/scheduler/sched-rt-group.txt for more information.
771
772endif #CGROUP_SCHED
773
Vivek Goyalafc24d42010-04-26 19:27:56 +0200774config BLK_CGROUP
775 tristate "Block IO controller"
Daniel Lezcano79ae9c22010-10-27 15:34:39 -0700776 depends on BLOCK
Vivek Goyalafc24d42010-04-26 19:27:56 +0200777 default n
778 ---help---
779 Generic block IO controller cgroup interface. This is the common
780 cgroup interface which should be used by various IO controlling
781 policies.
782
783 Currently, CFQ IO scheduler uses it to recognize task groups and
784 control disk bandwidth allocation (proportional time slice allocation)
Vivek Goyale43473b2010-09-15 17:06:35 -0400785 to such task groups. It is also used by bio throttling logic in
786 block layer to implement upper limit in IO rates on a device.
Vivek Goyalafc24d42010-04-26 19:27:56 +0200787
788 This option only enables generic Block IO controller infrastructure.
Vivek Goyale43473b2010-09-15 17:06:35 -0400789 One needs to also enable actual IO controlling logic/policy. For
Michael Witten79e2e752011-01-16 21:43:10 +0000790 enabling proportional weight division of disk bandwidth in CFQ, set
791 CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
Michael Wittenc5e05912011-01-17 00:08:41 +0000792 CONFIG_BLK_DEV_THROTTLING=y.
Vivek Goyalafc24d42010-04-26 19:27:56 +0200793
794 See Documentation/cgroups/blkio-controller.txt for more information.
795
796config DEBUG_BLK_CGROUP
797 bool "Enable Block IO controller debugging"
798 depends on BLK_CGROUP
799 default n
800 ---help---
801 Enable some debugging help. Currently it exports additional stat
802 files in a cgroup which can be useful for debugging.
803
Li Zefan23964d22009-01-15 13:50:58 -0800804endif # CGROUPS
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800805
Cyrill Gorcunov067bce12012-01-12 17:20:49 -0800806config CHECKPOINT_RESTORE
807 bool "Checkpoint/restore support" if EXPERT
808 default n
809 help
810 Enables additional kernel features in a sake of checkpoint/restore.
811 In particular it adds auxiliary prctl codes to setup process text,
812 data and heap segment sizes, and a few additional /proc filesystem
813 entries.
814
815 If unsure, say N here.
816
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700817menuconfig NAMESPACES
David Rientjes6a108a12011-01-20 14:44:16 -0800818 bool "Namespaces support" if EXPERT
819 default !EXPERT
Pavel Emelyanovc5289a62008-02-08 04:18:19 -0800820 help
821 Provides the way to make tasks work with different objects using
822 the same id. For example same IPC id may refer to different objects
823 or same user id or pid may refer to different tasks when used in
824 different namespaces.
825
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700826if NAMESPACES
827
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -0800828config UTS_NS
829 bool "UTS namespace"
Daniel Lezcano17a6d442010-10-27 15:34:37 -0700830 default y
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -0800831 help
832 In this namespace tasks see different info provided with the
833 uname() system call
834
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800835config IPC_NS
836 bool "IPC namespace"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700837 depends on (SYSVIPC || POSIX_MQUEUE)
Daniel Lezcano17a6d442010-10-27 15:34:37 -0700838 default y
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800839 help
840 In this namespace tasks work with IPC ids which correspond to
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700841 different IPC objects in different namespaces.
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800842
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -0800843config USER_NS
844 bool "User namespace (EXPERIMENTAL)"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700845 depends on EXPERIMENTAL
Daniel Lezcano17a6d442010-10-27 15:34:37 -0700846 default y
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -0800847 help
848 This allows containers, i.e. vservers, to use user namespaces
849 to provide different user info for different servers.
850 If unsure, say N.
851
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800852config PID_NS
Daniel Lezcano9bd38c22010-10-27 15:34:37 -0700853 bool "PID Namespaces"
Daniel Lezcano17a6d442010-10-27 15:34:37 -0700854 default y
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800855 help
Heikki Orsila12d2b8f2008-07-06 15:48:02 +0300856 Support process id namespaces. This allows having multiple
Matt LaPlante692105b2009-01-26 11:12:25 +0100857 processes with the same pid as long as they are in different
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800858 pid namespaces. This is a building block of containers.
859
Matt Helsleyd6eb6332009-01-26 12:25:55 -0800860config NET_NS
861 bool "Network namespace"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700862 depends on NET
Daniel Lezcano17a6d442010-10-27 15:34:37 -0700863 default y
Matt Helsleyd6eb6332009-01-26 12:25:55 -0800864 help
865 Allow user space to create what appear to be multiple instances
866 of the network stack.
867
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700868endif # NAMESPACES
869
Mike Galbraith5091faa2010-11-30 14:18:03 +0100870config SCHED_AUTOGROUP
871 bool "Automatic process group scheduling"
872 select EVENTFD
873 select CGROUPS
874 select CGROUP_SCHED
875 select FAIR_GROUP_SCHED
876 help
877 This option optimizes the scheduler for common desktop workloads by
878 automatically creating and populating task groups. This separation
879 of workloads isolates aggressive CPU burners (like build jobs) from
880 desktop applications. Task group autogeneration is currently based
881 upon task session.
882
Daniel Lezcano7af37be2010-10-27 15:34:41 -0700883config MM_OWNER
884 bool
885
886config SYSFS_DEPRECATED
Ferenc Wagner5d6a4ea2011-01-10 19:04:22 +0100887 bool "Enable deprecated sysfs features to support old userspace tools"
Daniel Lezcano7af37be2010-10-27 15:34:41 -0700888 depends on SYSFS
889 default n
890 help
891 This option adds code that switches the layout of the "block" class
892 devices, to not show up in /sys/class/block/, but only in
893 /sys/block/.
894
895 This switch is only active when the sysfs.deprecated=1 boot option is
896 passed or the SYSFS_DEPRECATED_V2 option is set.
897
898 This option allows new kernels to run on old distributions and tools,
899 which might get confused by /sys/class/block/. Since 2007/2008 all
900 major distributions and tools handle this just fine.
901
902 Recent distributions and userspace tools after 2009/2010 depend on
903 the existence of /sys/class/block/, and will not work with this
904 option enabled.
905
906 Only if you are using a new kernel on an old distribution, you might
907 need to say Y here.
908
909config SYSFS_DEPRECATED_V2
Ferenc Wagner5d6a4ea2011-01-10 19:04:22 +0100910 bool "Enable deprecated sysfs features by default"
Daniel Lezcano7af37be2010-10-27 15:34:41 -0700911 default n
912 depends on SYSFS
913 depends on SYSFS_DEPRECATED
914 help
915 Enable deprecated sysfs by default.
916
917 See the CONFIG_SYSFS_DEPRECATED option for more details about this
918 option.
919
920 Only if you are using a new kernel on an old distribution, you might
921 need to say Y here. Even then, odds are you would not need it
922 enabled, you can always pass the boot option if absolutely necessary.
923
924config RELAY
925 bool "Kernel->user space relay support (formerly relayfs)"
926 help
927 This option enables support for relay interface support in
928 certain file systems (such as debugfs).
929 It is designed to provide an efficient mechanism for tools and
930 facilities to relay large amounts of data from kernel space to
931 user space.
932
933 If unsure, say N.
934
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -0800935config BLK_DEV_INITRD
936 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
937 depends on BROKEN || !FRV
938 help
939 The initial RAM filesystem is a ramfs which is loaded by the
940 boot loader (loadlin or lilo) and that is mounted as root
941 before the normal boot procedure. It is typically used to
942 load modules needed to mount the "real" root file system,
943 etc. See <file:Documentation/initrd.txt> for details.
944
945 If RAM disk support (BLK_DEV_RAM) is also included, this
946 also enables initial RAM disk (initrd) support and adds
947 15 Kbytes (more on some other architectures) to the kernel size.
948
949 If unsure say Y.
950
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800951if BLK_DEV_INITRD
952
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200953source "usr/Kconfig"
954
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800955endif
956
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800957config CC_OPTIMIZE_FOR_SIZE
Ingo Molnar96fffeb2008-04-28 01:39:43 +0200958 bool "Optimize for size"
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800959 help
960 Enabling this option will pass "-Os" instead of "-O2" to gcc
961 resulting in a smaller kernel.
962
jkacur775a7222008-07-16 00:31:16 +0200963 If unsure, say Y.
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800964
Randy Dunlap08470622006-09-30 23:28:13 -0700965config SYSCTL
966 bool
967
Randy Dunlapb943c462009-03-10 12:55:46 -0700968config ANON_INODES
969 bool
970
David Rientjes6a108a12011-01-20 14:44:16 -0800971menuconfig EXPERT
972 bool "Configure standard kernel features (expert users)"
Josh Triplettf505c552011-06-05 18:23:58 -0700973 # Unhide debug options, to make the on-by-default options visible
974 select DEBUG_KERNEL
Linus Torvalds1da177e2005-04-16 15:20:36 -0700975 help
976 This option allows certain base kernel options and settings
977 to be disabled or tweaked. This is for specialized
978 environments which can tolerate a "non-standard" kernel.
979 Only use this if you really know what you are doing.
980
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700981config UID16
David Rientjes6a108a12011-01-20 14:44:16 -0800982 bool "Enable 16-bit UID system calls" if EXPERT
David S. Miller09337f52008-04-26 03:17:12 -0700983 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 -0700984 default y
985 help
986 This enables the legacy 16-bit UID syscall wrappers.
987
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700988config SYSCTL_SYSCALL
David Rientjes6a108a12011-01-20 14:44:16 -0800989 bool "Sysctl syscall support" if EXPERT
Eric W. Biederman26a70342009-11-05 05:26:41 -0800990 depends on PROC_SYSCTL
WANG Congc736de62011-11-02 13:39:25 -0700991 default n
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700992 select SYSCTL
993 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800994 sys_sysctl uses binary paths that have been found challenging
995 to properly maintain and use. The interface in /proc/sys
996 using paths with ascii names is now the primary path to this
997 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700998
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800999 Almost nothing using the binary sysctl interface so if you are
1000 trying to save some space it is probably safe to disable this,
1001 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001002
WANG Congc736de62011-11-02 13:39:25 -07001003 If unsure say N here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001004
Linus Torvalds1da177e2005-04-16 15:20:36 -07001005config KALLSYMS
David Rientjes6a108a12011-01-20 14:44:16 -08001006 bool "Load all symbols for debugging/ksymoops" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001007 default y
1008 help
1009 Say Y here to let the kernel print out symbolic crash information and
1010 symbolic stack backtraces. This increases the size of the kernel
1011 somewhat, as all symbols have to be loaded into the kernel image.
1012
1013config KALLSYMS_ALL
1014 bool "Include all symbols in kallsyms"
1015 depends on DEBUG_KERNEL && KALLSYMS
1016 help
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001017 Normally kallsyms only contains the symbols of functions for nicer
1018 OOPS messages and backtraces (i.e., symbols from the text and inittext
1019 sections). This is sufficient for most cases. And only in very rare
1020 cases (e.g., when a debugger is used) all symbols are required (e.g.,
1021 names of variables from the data sections, etc).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001022
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001023 This option makes sure that all symbols are loaded into the kernel
1024 image (i.e., symbols from all sections) in cost of increased kernel
1025 size (depending on the kernel configuration, it may be 300KiB or
1026 something like this).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001027
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001028 Say N unless you really need all symbols.
Matt Mackalld59745c2005-05-01 08:59:02 -07001029
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -08001030config HOTPLUG
David Rientjes6a108a12011-01-20 14:44:16 -08001031 bool "Support for hot-pluggable devices" if EXPERT
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -08001032 default y
1033 help
1034 This option is provided for the case where no hotplug or uevent
1035 capabilities is wanted by the kernel. You should only consider
1036 disabling this option for embedded systems that do not use modules, a
1037 dynamic /dev tree, or dynamic device discovery. Just say Y.
1038
Matt Mackalld59745c2005-05-01 08:59:02 -07001039config PRINTK
1040 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001041 bool "Enable support for printk" if EXPERT
Matt Mackalld59745c2005-05-01 08:59:02 -07001042 help
1043 This option enables normal printk support. Removing it
1044 eliminates most of the message strings from the kernel image
1045 and makes the kernel more or less silent. As this makes it
1046 very difficult to diagnose system problems, saying N here is
1047 strongly discouraged.
1048
Matt Mackallc8538a72005-05-01 08:59:01 -07001049config BUG
David Rientjes6a108a12011-01-20 14:44:16 -08001050 bool "BUG() support" if EXPERT
Matt Mackallc8538a72005-05-01 08:59:01 -07001051 default y
1052 help
1053 Disabling this option eliminates support for BUG and WARN, reducing
1054 the size of your kernel image and potentially quietly ignoring
1055 numerous fatal conditions. You should only consider disabling this
1056 option for embedded systems with no facilities for reporting errors.
1057 Just say Y.
1058
Matt Mackall708e9a72006-01-08 01:05:25 -08001059config ELF_CORE
1060 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001061 bool "Enable ELF core dumps" if EXPERT
Matt Mackall708e9a72006-01-08 01:05:25 -08001062 help
1063 Enable support for generating core dumps. Disabling saves about 4k.
1064
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001065
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +02001066config PCSPKR_PLATFORM
David Rientjes6a108a12011-01-20 14:44:16 -08001067 bool "Enable PC-Speaker support" if EXPERT
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001068 depends on HAVE_PCSPKR_PLATFORM
Ralf Baechle15f304b2011-06-01 19:04:59 +01001069 select I8253_LOCK
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +02001070 default y
1071 help
1072 This option allows to disable the internal PC-Speaker
1073 support, saving some memory.
1074
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001075config HAVE_PCSPKR_PLATFORM
1076 bool
1077
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078config BASE_FULL
1079 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001080 bool "Enable full-sized data structures for core" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001081 help
1082 Disabling this option reduces the size of miscellaneous core
1083 kernel data structures. This saves memory on small machines,
1084 but may reduce performance.
1085
1086config FUTEX
David Rientjes6a108a12011-01-20 14:44:16 -08001087 bool "Enable futex support" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001088 default y
Ingo Molnar23f78d4a2006-06-27 02:54:53 -07001089 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090 help
1091 Disabling this option will cause the kernel to be built without
1092 support for "fast userspace mutexes". The resulting kernel may not
1093 run glibc-based applications correctly.
1094
1095config EPOLL
David Rientjes6a108a12011-01-20 14:44:16 -08001096 bool "Enable eventpoll support" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001097 default y
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001098 select ANON_INODES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099 help
1100 Disabling this option will cause the kernel to be built without
1101 support for epoll family of system calls.
1102
Davide Libenzifba2afa2007-05-10 22:23:13 -07001103config SIGNALFD
David Rientjes6a108a12011-01-20 14:44:16 -08001104 bool "Enable signalfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001105 select ANON_INODES
Davide Libenzifba2afa2007-05-10 22:23:13 -07001106 default y
1107 help
1108 Enable the signalfd() system call that allows to receive signals
1109 on a file descriptor.
1110
1111 If unsure, say Y.
1112
Davide Libenzib215e282007-05-10 22:23:16 -07001113config TIMERFD
David Rientjes6a108a12011-01-20 14:44:16 -08001114 bool "Enable timerfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001115 select ANON_INODES
Davide Libenzib215e282007-05-10 22:23:16 -07001116 default y
1117 help
1118 Enable the timerfd() system call that allows to receive timer
1119 events on a file descriptor.
1120
1121 If unsure, say Y.
1122
Davide Libenzie1ad7462007-05-10 22:23:19 -07001123config EVENTFD
David Rientjes6a108a12011-01-20 14:44:16 -08001124 bool "Enable eventfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001125 select ANON_INODES
Davide Libenzie1ad7462007-05-10 22:23:19 -07001126 default y
1127 help
1128 Enable the eventfd() system call that allows to receive both
1129 kernel notification (ie. KAIO) or userspace notifications.
1130
1131 If unsure, say Y.
1132
Linus Torvalds1da177e2005-04-16 15:20:36 -07001133config SHMEM
David Rientjes6a108a12011-01-20 14:44:16 -08001134 bool "Use full shmem filesystem" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135 default y
1136 depends on MMU
1137 help
1138 The shmem is an internal filesystem used to manage shared memory.
1139 It is backed by swap and manages resource limits. It is also exported
1140 to userspace as tmpfs if TMPFS is enabled. Disabling this
1141 option replaces shmem and tmpfs with the much simpler ramfs code,
1142 which may be appropriate on small systems without swap.
1143
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001144config AIO
David Rientjes6a108a12011-01-20 14:44:16 -08001145 bool "Enable AIO support" if EXPERT
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001146 default y
1147 help
1148 This option enables POSIX asynchronous I/O which may by used
1149 by some high performance threaded applications. Disabling
1150 this option saves about 7k.
1151
Randy Dunlap6befe5f2011-04-26 12:33:21 -07001152config EMBEDDED
1153 bool "Embedded system"
1154 select EXPERT
1155 help
1156 This option should be enabled if compiling the kernel for
1157 an embedded system so certain expert options are available
1158 for configuration.
1159
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001160config HAVE_PERF_EVENTS
Thomas Gleixner0793a612008-12-04 20:12:29 +01001161 bool
Mike Frysinger018df722009-06-12 13:17:43 -04001162 help
1163 See tools/perf/design.txt for details.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001164
Peter Zijlstra906010b2009-09-21 16:08:49 +02001165config PERF_USE_VMALLOC
1166 bool
1167 help
1168 See tools/perf/design.txt for details
1169
Ingo Molnar57c0c152009-09-21 12:20:38 +02001170menu "Kernel Performance Events And Counters"
Thomas Gleixner0793a612008-12-04 20:12:29 +01001171
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001172config PERF_EVENTS
Ingo Molnar57c0c152009-09-21 12:20:38 +02001173 bool "Kernel performance events and counters"
1174 default y if (PROFILING || PERF_COUNTERS)
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001175 depends on HAVE_PERF_EVENTS
Ingo Molnar4c59e462008-12-08 19:38:33 +01001176 select ANON_INODES
Peter Zijlstrae360adb2010-10-14 14:01:34 +08001177 select IRQ_WORK
Thomas Gleixner0793a612008-12-04 20:12:29 +01001178 help
Ingo Molnar57c0c152009-09-21 12:20:38 +02001179 Enable kernel support for various performance events provided
1180 by software and hardware.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001181
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001182 Software events are supported either built-in or via the
Ingo Molnar57c0c152009-09-21 12:20:38 +02001183 use of generic tracepoints.
1184
1185 Most modern CPUs support performance events via performance
1186 counter registers. These registers count the number of certain
Thomas Gleixner0793a612008-12-04 20:12:29 +01001187 types of hw events: such as instructions executed, cachemisses
1188 suffered, or branches mis-predicted - without slowing down the
1189 kernel or applications. These registers can also trigger interrupts
1190 when a threshold number of events have passed - and can thus be
1191 used to profile the code that runs on that CPU.
1192
Ingo Molnar57c0c152009-09-21 12:20:38 +02001193 The Linux Performance Event subsystem provides an abstraction of
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001194 these software and hardware event capabilities, available via a
Ingo Molnar57c0c152009-09-21 12:20:38 +02001195 system call and used by the "perf" utility in tools/perf/. It
Thomas Gleixner0793a612008-12-04 20:12:29 +01001196 provides per task and per CPU counters, and it provides event
1197 capabilities on top of those.
1198
1199 Say Y if unsure.
1200
Ingo Molnar57c0c152009-09-21 12:20:38 +02001201config PERF_COUNTERS
1202 bool "Kernel performance counters (old config option)"
1203 depends on HAVE_PERF_EVENTS
1204 help
1205 This config has been obsoleted by the PERF_EVENTS
1206 config option - please see that one for details.
1207
1208 It has no effect on the kernel whether you enable
1209 it or not, it is a compatibility placeholder.
1210
1211 Say N if unsure.
1212
Peter Zijlstra906010b2009-09-21 16:08:49 +02001213config DEBUG_PERF_USE_VMALLOC
1214 default n
1215 bool "Debug: use vmalloc to back perf mmap() buffers"
1216 depends on PERF_EVENTS && DEBUG_KERNEL
1217 select PERF_USE_VMALLOC
1218 help
1219 Use vmalloc memory to back perf mmap() buffers.
1220
1221 Mostly useful for debugging the vmalloc code on platforms
1222 that don't require it.
1223
1224 Say N if unsure.
1225
Thomas Gleixner0793a612008-12-04 20:12:29 +01001226endmenu
1227
Christoph Lameterf8891e52006-06-30 01:55:45 -07001228config VM_EVENT_COUNTERS
1229 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001230 bool "Enable VM event counters for /proc/vmstat" if EXPERT
Christoph Lameterf8891e52006-06-30 01:55:45 -07001231 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001232 VM event counters are needed for event counts to be shown.
1233 This option allows the disabling of the VM event counters
David Rientjes6a108a12011-01-20 14:44:16 -08001234 on EXPERT systems. /proc/vmstat will only show page counts
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001235 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -07001236
Thomas Petazzoni3d137312008-08-19 10:28:24 +02001237config PCI_QUIRKS
1238 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001239 bool "Enable PCI quirk workarounds" if EXPERT
Geert Uytterhoeven61cfc7e2008-10-22 08:53:25 +02001240 depends on PCI
Thomas Petazzoni3d137312008-08-19 10:28:24 +02001241 help
1242 This enables workarounds for various PCI chipset
1243 bugs/quirks. Disable this only if your target machine is
1244 unaffected by PCI quirks.
1245
Christoph Lameter41ecc552007-05-09 02:32:44 -07001246config SLUB_DEBUG
1247 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001248 bool "Enable SLUB debugging support" if EXPERT
Christoph Lameterf6acb632008-04-29 16:16:06 -07001249 depends on SLUB && SYSFS
Christoph Lameter41ecc552007-05-09 02:32:44 -07001250 help
1251 SLUB has extensive debug support features. Disabling these can
1252 result in significant savings in code size. This also disables
1253 SLUB sysfs support. /sys/slab will not exist and there will be
1254 no support for cache validation etc.
1255
Randy Dunlapb943c462009-03-10 12:55:46 -07001256config COMPAT_BRK
1257 bool "Disable heap randomization"
1258 default y
1259 help
1260 Randomizing heap placement makes heap exploits harder, but it
1261 also breaks ancient binaries (including anything libc5 based).
1262 This option changes the bootup default to heap randomization
Matt LaPlante692105b2009-01-26 11:12:25 +01001263 disabled, and can be overridden at runtime by setting
Randy Dunlapb943c462009-03-10 12:55:46 -07001264 /proc/sys/kernel/randomize_va_space to 2.
1265
1266 On non-ancient distros (post-2000 ones) N is usually a safe choice.
1267
Christoph Lameter81819f02007-05-06 14:49:36 -07001268choice
1269 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -07001270 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001271 help
1272 This option allows to select a slab allocator.
1273
1274config SLAB
1275 bool "SLAB"
1276 help
1277 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -07001278 well in all environments. It organizes cache hot objects in
Simon Arlott02f56212008-11-05 22:18:19 +00001279 per cpu and per node queues.
Christoph Lameter81819f02007-05-06 14:49:36 -07001280
1281config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001282 bool "SLUB (Unqueued Allocator)"
1283 help
1284 SLUB is a slab allocator that minimizes cache line usage
1285 instead of managing queues of cached objects (SLAB approach).
1286 Per cpu caching is realized using slabs of objects instead
1287 of queues of objects. SLUB can use memory efficiently
Simon Arlott02f56212008-11-05 22:18:19 +00001288 and has enhanced diagnostics. SLUB is the default choice for
1289 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -07001290
1291config SLOB
David Rientjes6a108a12011-01-20 14:44:16 -08001292 depends on EXPERT
Christoph Lameter81819f02007-05-06 14:49:36 -07001293 bool "SLOB (Simple Allocator)"
1294 help
Matt Mackall37291452008-02-04 22:29:38 -08001295 SLOB replaces the stock allocator with a drastically simpler
1296 allocator. SLOB is generally more space efficient but
1297 does not perform as well on large systems.
Christoph Lameter81819f02007-05-06 14:49:36 -07001298
1299endchoice
1300
Jie Zhangea637632009-12-14 18:00:02 -08001301config MMAP_ALLOW_UNINITIALIZED
1302 bool "Allow mmapped anonymous memory to be uninitialized"
David Rientjes6a108a12011-01-20 14:44:16 -08001303 depends on EXPERT && !MMU
Jie Zhangea637632009-12-14 18:00:02 -08001304 default n
1305 help
1306 Normally, and according to the Linux spec, anonymous memory obtained
1307 from mmap() has it's contents cleared before it is passed to
1308 userspace. Enabling this config option allows you to request that
1309 mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus
1310 providing a huge performance boost. If this option is not enabled,
1311 then the flag will be ignored.
1312
1313 This is taken advantage of by uClibc's malloc(), and also by
1314 ELF-FDPIC binfmt's brk and stack allocator.
1315
1316 Because of the obvious security issues, this option should only be
1317 enabled on embedded devices where you control what is run in
1318 userspace. Since that isn't generally a problem on no-MMU systems,
1319 it is normally safe to say Y here.
1320
1321 See Documentation/nommu-mmap.txt for more information.
1322
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001323config PROFILING
Robert Richterb309a292010-02-26 15:01:23 +01001324 bool "Profiling support"
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001325 help
1326 Say Y here to enable the extended profiling support mechanisms used
1327 by profilers such as OProfile.
1328
Ingo Molnar5f87f112008-07-23 14:15:22 +02001329#
1330# Place an empty function call at each tracepoint site. Can be
1331# dynamically changed for a probe function.
1332#
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001333config TRACEPOINTS
Ingo Molnar5f87f112008-07-23 14:15:22 +02001334 bool
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001335
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -05001336source "arch/Kconfig"
1337
Linus Torvalds1da177e2005-04-16 15:20:36 -07001338endmenu # General setup
1339
Dmitry Baryshkovee7e5512008-06-29 14:18:46 +04001340config HAVE_GENERIC_DMA_COHERENT
1341 bool
1342 default n
1343
Linus Torvalds158a9622008-01-02 13:04:48 -08001344config SLABINFO
1345 bool
1346 depends on PROC_FS
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001347 depends on SLAB || SLUB_DEBUG
Linus Torvalds158a9622008-01-02 13:04:48 -08001348 default y
1349
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001350config RT_MUTEXES
1351 boolean
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001352
Linus Torvalds1da177e2005-04-16 15:20:36 -07001353config BASE_SMALL
1354 int
1355 default 0 if BASE_FULL
1356 default 1 if !BASE_FULL
1357
Jan Engelhardt66da5732007-07-15 23:39:29 -07001358menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001359 bool "Enable loadable module support"
1360 help
1361 Kernel modules are small pieces of compiled code which can
1362 be inserted in the running kernel, rather than being
1363 permanently built into the kernel. You use the "modprobe"
1364 tool to add (and sometimes remove) them. If you say Y here,
1365 many parts of the kernel can be built as modules (by
1366 answering M instead of Y where indicated): this is most
1367 useful for infrequently used options which are not required
1368 for booting. For more information, see the man pages for
1369 modprobe, lsmod, modinfo, insmod and rmmod.
1370
1371 If you say Y here, you will need to run "make
1372 modules_install" to put the modules under /lib/modules/
1373 where modprobe can find them (you may need to be root to do
1374 this).
1375
1376 If unsure, say Y.
1377
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001378if MODULES
1379
Linus Torvalds826e4502008-05-04 17:04:16 -07001380config MODULE_FORCE_LOAD
1381 bool "Forced module loading"
Linus Torvalds826e4502008-05-04 17:04:16 -07001382 default n
1383 help
Rusty Russell91e37a72008-05-09 16:25:28 +10001384 Allow loading of modules without version information (ie. modprobe
1385 --force). Forced module loading sets the 'F' (forced) taint flag and
1386 is usually a really bad idea.
Linus Torvalds826e4502008-05-04 17:04:16 -07001387
Linus Torvalds1da177e2005-04-16 15:20:36 -07001388config MODULE_UNLOAD
1389 bool "Module unloading"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001390 help
1391 Without this option you will not be able to unload any
1392 modules (note that some modules may not be unloadable
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001393 anyway), which makes your kernel smaller, faster
1394 and simpler. If unsure, say Y.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001395
1396config MODULE_FORCE_UNLOAD
1397 bool "Forced module unloading"
1398 depends on MODULE_UNLOAD && EXPERIMENTAL
1399 help
1400 This option allows you to force a module to unload, even if the
1401 kernel believes it is unsafe: the kernel will remove the module
1402 without waiting for anyone to stop using it (using the -f option to
1403 rmmod). This is mainly for kernel developers and desperate users.
1404 If unsure, say N.
1405
Linus Torvalds1da177e2005-04-16 15:20:36 -07001406config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +01001407 bool "Module versioning support"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001408 help
1409 Usually, you have to use modules compiled with your kernel.
1410 Saying Y here makes it sometimes possible to use modules
1411 compiled for different kernels, by adding enough information
1412 to the modules to (hopefully) spot any changes which would
1413 make them incompatible with the kernel you are running. If
1414 unsure, say N.
1415
1416config MODULE_SRCVERSION_ALL
1417 bool "Source checksum for all modules"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001418 help
1419 Modules which contain a MODULE_VERSION get an extra "srcversion"
1420 field inserted into their modinfo section, which contains a
1421 sum of the source files which made it. This helps maintainers
1422 see exactly which source was used to build a module (since
1423 others sometimes change the module source without updating
1424 the version). With this option, such a "srcversion" field
1425 will be created for all modules. If unsure, say N.
1426
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001427endif # MODULES
1428
Rusty Russell98a79d62008-12-13 21:19:41 +10301429config INIT_ALL_POSSIBLE
1430 bool
1431 help
Rusty Russell5f054e32012-03-29 15:38:31 +10301432 Back when each arch used to define their own cpu_online_mask and
1433 cpu_possible_mask, some of them chose to initialize cpu_possible_mask
Rusty Russell98a79d62008-12-13 21:19:41 +10301434 with all 1s, and others with all 0s. When they were centralised,
1435 it was better to provide this option than to break all the archs
Matt LaPlante692105b2009-01-26 11:12:25 +01001436 and have several arch maintainers pursuing me down dark alleys.
Rusty Russell98a79d62008-12-13 21:19:41 +10301437
Linus Torvalds1da177e2005-04-16 15:20:36 -07001438config STOP_MACHINE
1439 bool
1440 default y
1441 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
1442 help
1443 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001444
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001445source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -07001446
1447config PREEMPT_NOTIFIERS
1448 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +01001449
Steffen Klassert16295be2010-01-06 19:47:10 +11001450config PADATA
1451 depends on SMP
1452 bool
1453
Thomas Gleixner6beb0002009-11-09 15:21:34 +00001454source "kernel/Kconfig.locks"