blob: 3349670149dc13b64d3f58b8ef5c3b7239ab3930 [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53 drivers that have been replaced by something else, and/or are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
518 This option specifies the real-time priority to which preempted
519 RCU readers are to be boosted. If you are working with CPU-bound
520 real-time applications, you should specify a priority higher then
521 the highest-priority CPU-bound application.
522
523 Specify the real-time priority, or take the default if unsure.
524
525config RCU_BOOST_DELAY
526 int "Milliseconds to delay boosting after RCU grace-period start"
527 range 0 3000
528 depends on RCU_BOOST
529 default 500
530 help
531 This option specifies the time to wait after the beginning of
532 a given grace period before priority-boosting preempted RCU
533 readers blocking that grace period. Note that any RCU reader
534 blocking an expedited RCU grace period is boosted immediately.
535
536 Accept the default if unsure.
537
Mike Travisc903ff82009-01-15 12:28:29 -0800538endmenu # "RCU Subsystem"
539
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700541 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 ---help---
543 This option enables the complete Linux kernel ".config" file
544 contents to be saved in the kernel. It provides documentation
545 of which kernel options are used in a running kernel or in an
546 on-disk kernel. This information can be extracted from the kernel
547 image file with the script scripts/extract-ikconfig and used as
548 input to rebuild the current kernel or to build another kernel.
549 It can also be extracted from a running kernel by reading
550 /proc/config.gz if enabled (below).
551
552config IKCONFIG_PROC
553 bool "Enable access to .config through /proc/config.gz"
554 depends on IKCONFIG && PROC_FS
555 ---help---
556 This option enables access to the kernel configuration file
557 through /proc/config.gz.
558
Alistair John Strachan794543a2007-05-08 00:31:15 -0700559config LOG_BUF_SHIFT
560 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
561 range 12 21
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700562 default 17
Alistair John Strachan794543a2007-05-08 00:31:15 -0700563 help
564 Select kernel log buffer size as a power of 2.
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700565 Examples:
566 17 => 128 KB
567 16 => 64 KB
568 15 => 32 KB
569 14 => 16 KB
Alistair John Strachan794543a2007-05-08 00:31:15 -0700570 13 => 8 KB
571 12 => 4 KB
572
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800573#
574# Architectures with an unreliable sched_clock() should select this:
575#
576config HAVE_UNSTABLE_SCHED_CLOCK
577 bool
578
Li Zefan23964d22009-01-15 13:50:58 -0800579menuconfig CGROUPS
580 boolean "Control Group support"
Kirill A. Shutemov0dea1162010-03-10 15:22:20 -0800581 depends on EVENTFD
Paul Menageddbcc7e2007-10-18 23:39:30 -0700582 help
Li Zefan23964d22009-01-15 13:50:58 -0800583 This option adds support for grouping sets of processes together, for
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800584 use with process control subsystems such as Cpusets, CFS, memory
585 controls or device isolation.
586 See
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800587 - Documentation/scheduler/sched-design-CFS.txt (CFS)
Li Zefan45ce80f2009-01-15 13:50:59 -0800588 - Documentation/cgroups/ (features for grouping, isolation
589 and resource control)
Paul Menageddbcc7e2007-10-18 23:39:30 -0700590
591 Say N if unsure.
592
Li Zefan23964d22009-01-15 13:50:58 -0800593if CGROUPS
594
Paul Menage006cb992007-10-18 23:39:43 -0700595config CGROUP_DEBUG
596 bool "Example debug cgroup subsystem"
Paul Menage418d7d82008-04-29 01:00:05 -0700597 default n
Paul Menage006cb992007-10-18 23:39:43 -0700598 help
599 This option enables a simple cgroup subsystem that
600 exports useful debugging information about the cgroups
Li Zefan23964d22009-01-15 13:50:58 -0800601 framework.
Paul Menage006cb992007-10-18 23:39:43 -0700602
Li Zefan23964d22009-01-15 13:50:58 -0800603 Say N if unsure.
Paul Menage006cb992007-10-18 23:39:43 -0700604
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700605config CGROUP_FREEZER
Li Zefan23964d22009-01-15 13:50:58 -0800606 bool "Freezer cgroup subsystem"
Li Zefan23964d22009-01-15 13:50:58 -0800607 help
608 Provides a way to freeze and unfreeze all tasks in a
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700609 cgroup.
610
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700611config CGROUP_DEVICE
612 bool "Device controller for cgroups"
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700613 help
614 Provides a cgroup implementing whitelists for devices which
615 a process in the cgroup can mknod or open.
616
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617config CPUSETS
618 bool "Cpuset support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700620 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 allow dynamically partitioning a system into sets of CPUs and
622 Memory Nodes and assigning tasks to run only within those sets.
623 This is primarily useful on large SMP or NUMA systems.
624
625 Say N if unsure.
626
Li Zefan23964d22009-01-15 13:50:58 -0800627config PROC_PID_CPUSET
628 bool "Include legacy /proc/<pid>/cpuset file"
629 depends on CPUSETS
630 default y
631
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100632config CGROUP_CPUACCT
633 bool "Simple CPU accounting cgroup subsystem"
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100634 help
635 Provides a simple Resource Controller for monitoring the
Li Zefan23964d22009-01-15 13:50:58 -0800636 total CPU consumed by the tasks in a cgroup.
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100637
Pavel Emelianove552b662008-02-07 00:13:49 -0800638config RESOURCE_COUNTERS
639 bool "Resource counters"
640 help
641 This option enables controller independent resource accounting
Li Zefan23964d22009-01-15 13:50:58 -0800642 infrastructure that works with cgroups.
Pavel Emelianove552b662008-02-07 00:13:49 -0800643
Balbir Singh00f0b822008-03-04 14:28:39 -0800644config CGROUP_MEM_RES_CTLR
645 bool "Memory Resource Controller for Control Groups"
Daniel Lezcano79ae9c22010-10-27 15:34:39 -0700646 depends on RESOURCE_COUNTERS
Balbir Singhcf475ad2008-04-29 01:00:16 -0700647 select MM_OWNER
Balbir Singh00f0b822008-03-04 14:28:39 -0800648 help
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700649 Provides a memory resource controller that manages both anonymous
Thadeu Lima de Souza Cascardo21acb9c2009-02-04 10:12:08 +0100650 memory and page cache. (See Documentation/cgroups/memory.txt)
Balbir Singh00f0b822008-03-04 14:28:39 -0800651
652 Note that setting this option increases fixed memory overhead
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700653 associated with each page of memory in the system. By this,
654 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
655 usage tracking struct at boot. Total amount of this is printed out
656 at boot.
Balbir Singh00f0b822008-03-04 14:28:39 -0800657
658 Only enable when you're ok with these trade offs and really
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700659 sure you need the memory resource controller. Even when you enable
660 this, you can set "cgroup_disable=memory" at your boot option to
661 disable memory resource controller and you can avoid overheads.
Li Zefanc9d54092009-01-07 18:07:35 -0800662 (and lose benefits of memory resource controller)
Balbir Singh00f0b822008-03-04 14:28:39 -0800663
Balbir Singhcf475ad2008-04-29 01:00:16 -0700664 This config option also selects MM_OWNER config option, which
665 could in turn add some fork/exit overhead.
666
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800667config CGROUP_MEM_RES_CTLR_SWAP
KAMEZAWA Hiroyuki65e0e812010-08-10 18:02:56 -0700668 bool "Memory Resource Controller Swap Extension"
669 depends on CGROUP_MEM_RES_CTLR && SWAP
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800670 help
671 Add swap management feature to memory resource controller. When you
672 enable this, you can limit mem+swap usage per cgroup. In other words,
673 when you disable this, memory resource controller has no cares to
674 usage of swap...a process can exhaust all of the swap. This extension
675 is useful when you want to avoid exhaustion swap but this itself
676 adds more overheads and consumes memory for remembering information.
677 Especially if you use 32bit system or small memory system, please
678 be careful about enabling this. When memory resource controller
679 is disabled by boot option, this will be automatically disabled and
680 there will be no overhead from this. Even when you set this config=y,
WANG Cong00a66d22011-07-25 17:12:12 -0700681 if boot option "swapaccount=0" is set, swap will not be accounted.
KAMEZAWA Hiroyuki627991a2009-04-02 16:57:47 -0700682 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
683 size is 4096bytes, 512k per 1Gbytes of swap.
Michal Hockoa42c3902010-11-24 12:57:08 -0800684config CGROUP_MEM_RES_CTLR_SWAP_ENABLED
685 bool "Memory Resource Controller Swap Extension enabled by default"
686 depends on CGROUP_MEM_RES_CTLR_SWAP
687 default y
688 help
689 Memory Resource Controller Swap Extension comes with its price in
690 a bigger memory consumption. General purpose distribution kernels
Jim Cromie43d547f2010-12-17 14:32:36 -0700691 which want to enable the feature but keep it disabled by default
Michal Hockoa42c3902010-11-24 12:57:08 -0800692 and let the user enable it by swapaccount boot command line
693 parameter should have this option unselected.
694 For those who want to have the feature enabled by default should
695 select this option (if, for some reason, they need to disable it
WANG Cong00a66d22011-07-25 17:12:12 -0700696 then swapaccount=0 does the trick).
Glauber Costae5671df2011-12-11 21:47:01 +0000697config CGROUP_MEM_RES_CTLR_KMEM
698 bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
699 depends on CGROUP_MEM_RES_CTLR && EXPERIMENTAL
700 default n
701 help
702 The Kernel Memory extension for Memory Resource Controller can limit
703 the amount of memory used by kernel objects in the system. Those are
704 fundamentally different from the entities handled by the standard
705 Memory Controller, which are page-based, and can be swapped. Users of
706 the kmem extension can use it to guarantee that no group of processes
707 will ever exhaust kernel resources alone.
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800708
Stephane Eraniane5d13672011-02-14 11:20:01 +0200709config CGROUP_PERF
710 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
711 depends on PERF_EVENTS && CGROUPS
712 help
713 This option extends the per-cpu mode to restrict monitoring to
Li Zefan2d0f2522011-03-03 14:26:20 +0800714 threads which belong to the cgroup specified and run on the
Stephane Eraniane5d13672011-02-14 11:20:01 +0200715 designated cpu.
716
717 Say N if unsure.
718
Dhaval Giani7c941432010-01-20 13:26:18 +0100719menuconfig CGROUP_SCHED
720 bool "Group CPU scheduler"
Dhaval Giani7c941432010-01-20 13:26:18 +0100721 default n
722 help
723 This feature lets CPU scheduler recognize task groups and control CPU
724 bandwidth allocation to such task groups. It uses cgroups to group
725 tasks.
726
727if CGROUP_SCHED
728config FAIR_GROUP_SCHED
729 bool "Group scheduling for SCHED_OTHER"
730 depends on CGROUP_SCHED
731 default CGROUP_SCHED
732
Paul Turnerab84d312011-07-21 09:43:28 -0700733config CFS_BANDWIDTH
734 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
735 depends on EXPERIMENTAL
736 depends on FAIR_GROUP_SCHED
737 default n
738 help
739 This option allows users to define CPU bandwidth rates (limits) for
740 tasks running within the fair group scheduler. Groups with no limit
741 set are considered to be unconstrained and will run with no
742 restriction.
743 See tip/Documentation/scheduler/sched-bwc.txt for more information.
744
Dhaval Giani7c941432010-01-20 13:26:18 +0100745config RT_GROUP_SCHED
746 bool "Group scheduling for SCHED_RR/FIFO"
747 depends on EXPERIMENTAL
748 depends on CGROUP_SCHED
749 default n
750 help
751 This feature lets you explicitly allocate real CPU bandwidth
Li Zefan32bd7eb2010-03-24 13:17:19 +0800752 to task groups. If enabled, it will also make it impossible to
Dhaval Giani7c941432010-01-20 13:26:18 +0100753 schedule realtime tasks for non-root users until you allocate
754 realtime bandwidth for them.
755 See Documentation/scheduler/sched-rt-group.txt for more information.
756
757endif #CGROUP_SCHED
758
Vivek Goyalafc24d42010-04-26 19:27:56 +0200759config BLK_CGROUP
760 tristate "Block IO controller"
Daniel Lezcano79ae9c22010-10-27 15:34:39 -0700761 depends on BLOCK
Vivek Goyalafc24d42010-04-26 19:27:56 +0200762 default n
763 ---help---
764 Generic block IO controller cgroup interface. This is the common
765 cgroup interface which should be used by various IO controlling
766 policies.
767
768 Currently, CFQ IO scheduler uses it to recognize task groups and
769 control disk bandwidth allocation (proportional time slice allocation)
Vivek Goyale43473b2010-09-15 17:06:35 -0400770 to such task groups. It is also used by bio throttling logic in
771 block layer to implement upper limit in IO rates on a device.
Vivek Goyalafc24d42010-04-26 19:27:56 +0200772
773 This option only enables generic Block IO controller infrastructure.
Vivek Goyale43473b2010-09-15 17:06:35 -0400774 One needs to also enable actual IO controlling logic/policy. For
Michael Witten79e2e752011-01-16 21:43:10 +0000775 enabling proportional weight division of disk bandwidth in CFQ, set
776 CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
Michael Wittenc5e05912011-01-17 00:08:41 +0000777 CONFIG_BLK_DEV_THROTTLING=y.
Vivek Goyalafc24d42010-04-26 19:27:56 +0200778
779 See Documentation/cgroups/blkio-controller.txt for more information.
780
781config DEBUG_BLK_CGROUP
782 bool "Enable Block IO controller debugging"
783 depends on BLK_CGROUP
784 default n
785 ---help---
786 Enable some debugging help. Currently it exports additional stat
787 files in a cgroup which can be useful for debugging.
788
Li Zefan23964d22009-01-15 13:50:58 -0800789endif # CGROUPS
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800790
Cyrill Gorcunov067bce12012-01-12 17:20:49 -0800791config CHECKPOINT_RESTORE
792 bool "Checkpoint/restore support" if EXPERT
793 default n
794 help
795 Enables additional kernel features in a sake of checkpoint/restore.
796 In particular it adds auxiliary prctl codes to setup process text,
797 data and heap segment sizes, and a few additional /proc filesystem
798 entries.
799
800 If unsure, say N here.
801
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700802menuconfig NAMESPACES
David Rientjes6a108a12011-01-20 14:44:16 -0800803 bool "Namespaces support" if EXPERT
804 default !EXPERT
Pavel Emelyanovc5289a62008-02-08 04:18:19 -0800805 help
806 Provides the way to make tasks work with different objects using
807 the same id. For example same IPC id may refer to different objects
808 or same user id or pid may refer to different tasks when used in
809 different namespaces.
810
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700811if NAMESPACES
812
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -0800813config UTS_NS
814 bool "UTS namespace"
Daniel Lezcano17a6d442010-10-27 15:34:37 -0700815 default y
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -0800816 help
817 In this namespace tasks see different info provided with the
818 uname() system call
819
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800820config IPC_NS
821 bool "IPC namespace"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700822 depends on (SYSVIPC || POSIX_MQUEUE)
Daniel Lezcano17a6d442010-10-27 15:34:37 -0700823 default y
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800824 help
825 In this namespace tasks work with IPC ids which correspond to
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700826 different IPC objects in different namespaces.
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800827
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -0800828config USER_NS
829 bool "User namespace (EXPERIMENTAL)"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -0700830 depends on EXPERIMENTAL
Eric W. Biedermane1c972b2012-04-21 04:09:01 -0700831 depends on UIDGID_CONVERTED
Eric W. Biederman5673a942011-11-17 10:23:55 -0800832 select UIDGID_STRICT_TYPE_CHECKS
Eric W. Biedermane1c972b2012-04-21 04:09:01 -0700833
Eric W. Biederman5673a942011-11-17 10:23:55 -0800834 default n
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
Eric W. Biedermane1c972b2012-04-21 04:09:01 -0700858config UIDGID_CONVERTED
859 # True if all of the selected software conmponents are known
860 # to have uid_t and gid_t converted to kuid_t and kgid_t
861 # where appropriate and are otherwise safe to use with
862 # the user namespace.
863 bool
864 default y
865
866 # List of kernel pieces that need user namespace work
867 # Features
868 depends on BINFMT_ELF = n
869 depends on BINFMT_ELF_FDPIC = n
870 depends on UNIX98_PTYS = n
871 depends on CGROUPS = n
872 depends on MIGRATION = n
873 depends on NUMA = n
874 depends on SYSVIPC = n
875 depends on IMA = n
876 depends on EVM = n
877 depends on KEYS = n
878 depends on AUDIT = n
879 depends on AUDITSYSCALL = n
880 depends on TASKSTATS = n
881 depends on TRACING = n
882 depends on FS_POSIX_ACL = n
883 depends on QUOTA = n
884 depends on QUOTACTL = n
885 depends on DEBUG_CREDENTIALS = n
886 depends on BSD_PROCESS_ACCT = n
887 depends on DRM = n
888 depends on PROC_EVENTS = n
889
890 # Networking
891 depends on NET = n
892 depends on NET_9P = n
893 depends on IPX = n
894 depends on PHONET = n
895 depends on NET_CLS_FLOW = n
896 depends on NETFILTER_XT_MATCH_OWNER = n
897 depends on NETFILTER_XT_MATCH_RECENT = n
898 depends on NETFILTER_XT_TARGET_LOG = n
899 depends on NETFILTER_NETLINK_LOG = n
900 depends on INET = n
901 depends on IPV6 = n
902 depends on IP_SCTP = n
903 depends on AF_RXRPC = n
904 depends on LLC2 = n
905 depends on NET_KEY = n
906 depends on INET_DIAG = n
907 depends on DNS_RESOLVER = n
908 depends on AX25 = n
909 depends on ATALK = n
910
911 # Filesystems
912 depends on USB_DEVICEFS = n
913 depends on USB_GADGETFS = n
914 depends on USB_FUNCTIONFS = n
915 depends on DEVTMPFS = n
916 depends on XENFS = n
917
918 depends on 9P_FS = n
919 depends on ADFS_FS = n
920 depends on AFFS_FS = n
921 depends on AFS_FS = n
922 depends on AUTOFS4_FS = n
923 depends on BEFS_FS = n
924 depends on BFS_FS = n
925 depends on BTRFS_FS = n
926 depends on CEPH_FS = n
927 depends on CIFS = n
928 depends on CODA_FS = n
929 depends on CONFIGFS_FS = n
930 depends on CRAMFS = n
931 depends on DEBUG_FS = n
932 depends on ECRYPT_FS = n
933 depends on EFS_FS = n
934 depends on EXOFS_FS = n
935 depends on EXT2_FS = n
936 depends on EXT3_FS = n
937 depends on EXT4_FS = n
938 depends on FAT_FS = n
939 depends on FUSE_FS = n
940 depends on GFS2_FS = n
941 depends on HFS_FS = n
942 depends on HFSPLUS_FS = n
943 depends on HPFS_FS = n
944 depends on HUGETLBFS = n
945 depends on ISO9660_FS = n
946 depends on JFFS2_FS = n
947 depends on JFS_FS = n
948 depends on LOGFS = n
949 depends on MINIX_FS = n
950 depends on NCP_FS = n
951 depends on NFSD = n
952 depends on NFS_FS = n
953 depends on NILFS2_FS = n
954 depends on NTFS_FS = n
955 depends on OCFS2_FS = n
956 depends on OMFS_FS = n
957 depends on PROC_FS = n
958 depends on PROC_SYSCTL = n
959 depends on QNX4FS_FS = n
960 depends on QNX6FS_FS = n
961 depends on REISERFS_FS = n
962 depends on SQUASHFS = n
963 depends on SYSFS = n
964 depends on SYSV_FS = n
965 depends on TMPFS = n
966 depends on UBIFS_FS = n
967 depends on UDF_FS = n
968 depends on UFS_FS = n
969 depends on VXFS_FS = n
970 depends on XFS_FS = n
971
972 depends on !UML || HOSTFS = n
973
974 # The rare drivers that won't build
975 depends on AIRO = n
976 depends on AIRO_CS = n
977 depends on TUN = n
978 depends on INFINIBAND_QIB = n
979 depends on BLK_DEV_LOOP = n
980 depends on ANDROID_BINDER_IPC = n
981
982 # Security modules
983 depends on SECURITY_TOMOYO = n
984 depends on SECURITY_APPARMOR = n
985
Eric W. Biederman5673a942011-11-17 10:23:55 -0800986config UIDGID_STRICT_TYPE_CHECKS
987 bool "Require conversions between uid/gids and their internal representation"
Eric W. Biedermane1c972b2012-04-21 04:09:01 -0700988 depends on UIDGID_CONVERTED
Eric W. Biederman5673a942011-11-17 10:23:55 -0800989 default n
990 help
991 While the nececessary conversions are being added to all subsystems this option allows
992 the code to continue to build for unconverted subsystems.
993
994 Say Y here if you want the strict type checking enabled
995
Mike Galbraith5091faa2010-11-30 14:18:03 +0100996config SCHED_AUTOGROUP
997 bool "Automatic process group scheduling"
998 select EVENTFD
999 select CGROUPS
1000 select CGROUP_SCHED
1001 select FAIR_GROUP_SCHED
1002 help
1003 This option optimizes the scheduler for common desktop workloads by
1004 automatically creating and populating task groups. This separation
1005 of workloads isolates aggressive CPU burners (like build jobs) from
1006 desktop applications. Task group autogeneration is currently based
1007 upon task session.
1008
Daniel Lezcano7af37be2010-10-27 15:34:41 -07001009config MM_OWNER
1010 bool
1011
1012config SYSFS_DEPRECATED
Ferenc Wagner5d6a4ea2011-01-10 19:04:22 +01001013 bool "Enable deprecated sysfs features to support old userspace tools"
Daniel Lezcano7af37be2010-10-27 15:34:41 -07001014 depends on SYSFS
1015 default n
1016 help
1017 This option adds code that switches the layout of the "block" class
1018 devices, to not show up in /sys/class/block/, but only in
1019 /sys/block/.
1020
1021 This switch is only active when the sysfs.deprecated=1 boot option is
1022 passed or the SYSFS_DEPRECATED_V2 option is set.
1023
1024 This option allows new kernels to run on old distributions and tools,
1025 which might get confused by /sys/class/block/. Since 2007/2008 all
1026 major distributions and tools handle this just fine.
1027
1028 Recent distributions and userspace tools after 2009/2010 depend on
1029 the existence of /sys/class/block/, and will not work with this
1030 option enabled.
1031
1032 Only if you are using a new kernel on an old distribution, you might
1033 need to say Y here.
1034
1035config SYSFS_DEPRECATED_V2
Ferenc Wagner5d6a4ea2011-01-10 19:04:22 +01001036 bool "Enable deprecated sysfs features by default"
Daniel Lezcano7af37be2010-10-27 15:34:41 -07001037 default n
1038 depends on SYSFS
1039 depends on SYSFS_DEPRECATED
1040 help
1041 Enable deprecated sysfs by default.
1042
1043 See the CONFIG_SYSFS_DEPRECATED option for more details about this
1044 option.
1045
1046 Only if you are using a new kernel on an old distribution, you might
1047 need to say Y here. Even then, odds are you would not need it
1048 enabled, you can always pass the boot option if absolutely necessary.
1049
1050config RELAY
1051 bool "Kernel->user space relay support (formerly relayfs)"
1052 help
1053 This option enables support for relay interface support in
1054 certain file systems (such as debugfs).
1055 It is designed to provide an efficient mechanism for tools and
1056 facilities to relay large amounts of data from kernel space to
1057 user space.
1058
1059 If unsure, say N.
1060
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -08001061config BLK_DEV_INITRD
1062 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
1063 depends on BROKEN || !FRV
1064 help
1065 The initial RAM filesystem is a ramfs which is loaded by the
1066 boot loader (loadlin or lilo) and that is mounted as root
1067 before the normal boot procedure. It is typically used to
1068 load modules needed to mount the "real" root file system,
1069 etc. See <file:Documentation/initrd.txt> for details.
1070
1071 If RAM disk support (BLK_DEV_RAM) is also included, this
1072 also enables initial RAM disk (initrd) support and adds
1073 15 Kbytes (more on some other architectures) to the kernel size.
1074
1075 If unsure say Y.
1076
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -08001077if BLK_DEV_INITRD
1078
Sam Ravnborgdbec4862005-08-10 20:44:50 +02001079source "usr/Kconfig"
1080
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -08001081endif
1082
Linus Torvaldsc45b4f12005-12-14 18:52:21 -08001083config CC_OPTIMIZE_FOR_SIZE
Ingo Molnar96fffeb2008-04-28 01:39:43 +02001084 bool "Optimize for size"
Linus Torvaldsc45b4f12005-12-14 18:52:21 -08001085 help
1086 Enabling this option will pass "-Os" instead of "-O2" to gcc
1087 resulting in a smaller kernel.
1088
jkacur775a7222008-07-16 00:31:16 +02001089 If unsure, say Y.
Linus Torvaldsc45b4f12005-12-14 18:52:21 -08001090
Randy Dunlap08470622006-09-30 23:28:13 -07001091config SYSCTL
1092 bool
1093
Randy Dunlapb943c462009-03-10 12:55:46 -07001094config ANON_INODES
1095 bool
1096
David Rientjes6a108a12011-01-20 14:44:16 -08001097menuconfig EXPERT
1098 bool "Configure standard kernel features (expert users)"
Josh Triplettf505c552011-06-05 18:23:58 -07001099 # Unhide debug options, to make the on-by-default options visible
1100 select DEBUG_KERNEL
Linus Torvalds1da177e2005-04-16 15:20:36 -07001101 help
1102 This option allows certain base kernel options and settings
1103 to be disabled or tweaked. This is for specialized
1104 environments which can tolerate a "non-standard" kernel.
1105 Only use this if you really know what you are doing.
1106
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001107config UID16
David Rientjes6a108a12011-01-20 14:44:16 -08001108 bool "Enable 16-bit UID system calls" if EXPERT
David S. Miller09337f52008-04-26 03:17:12 -07001109 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 -07001110 default y
1111 help
1112 This enables the legacy 16-bit UID syscall wrappers.
1113
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001114config SYSCTL_SYSCALL
David Rientjes6a108a12011-01-20 14:44:16 -08001115 bool "Sysctl syscall support" if EXPERT
Eric W. Biederman26a70342009-11-05 05:26:41 -08001116 depends on PROC_SYSCTL
WANG Congc736de62011-11-02 13:39:25 -07001117 default n
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001118 select SYSCTL
1119 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -08001120 sys_sysctl uses binary paths that have been found challenging
1121 to properly maintain and use. The interface in /proc/sys
1122 using paths with ascii names is now the primary path to this
1123 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001124
Eric W. Biederman13bb7e32006-11-08 17:44:51 -08001125 Almost nothing using the binary sysctl interface so if you are
1126 trying to save some space it is probably safe to disable this,
1127 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001128
WANG Congc736de62011-11-02 13:39:25 -07001129 If unsure say N here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001130
Linus Torvalds1da177e2005-04-16 15:20:36 -07001131config KALLSYMS
David Rientjes6a108a12011-01-20 14:44:16 -08001132 bool "Load all symbols for debugging/ksymoops" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001133 default y
1134 help
1135 Say Y here to let the kernel print out symbolic crash information and
1136 symbolic stack backtraces. This increases the size of the kernel
1137 somewhat, as all symbols have to be loaded into the kernel image.
1138
1139config KALLSYMS_ALL
1140 bool "Include all symbols in kallsyms"
1141 depends on DEBUG_KERNEL && KALLSYMS
1142 help
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001143 Normally kallsyms only contains the symbols of functions for nicer
1144 OOPS messages and backtraces (i.e., symbols from the text and inittext
1145 sections). This is sufficient for most cases. And only in very rare
1146 cases (e.g., when a debugger is used) all symbols are required (e.g.,
1147 names of variables from the data sections, etc).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001149 This option makes sure that all symbols are loaded into the kernel
1150 image (i.e., symbols from all sections) in cost of increased kernel
1151 size (depending on the kernel configuration, it may be 300KiB or
1152 something like this).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001153
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001154 Say N unless you really need all symbols.
Matt Mackalld59745c2005-05-01 08:59:02 -07001155
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -08001156config HOTPLUG
David Rientjes6a108a12011-01-20 14:44:16 -08001157 bool "Support for hot-pluggable devices" if EXPERT
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -08001158 default y
1159 help
1160 This option is provided for the case where no hotplug or uevent
1161 capabilities is wanted by the kernel. You should only consider
1162 disabling this option for embedded systems that do not use modules, a
1163 dynamic /dev tree, or dynamic device discovery. Just say Y.
1164
Matt Mackalld59745c2005-05-01 08:59:02 -07001165config PRINTK
1166 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001167 bool "Enable support for printk" if EXPERT
Matt Mackalld59745c2005-05-01 08:59:02 -07001168 help
1169 This option enables normal printk support. Removing it
1170 eliminates most of the message strings from the kernel image
1171 and makes the kernel more or less silent. As this makes it
1172 very difficult to diagnose system problems, saying N here is
1173 strongly discouraged.
1174
Matt Mackallc8538a72005-05-01 08:59:01 -07001175config BUG
David Rientjes6a108a12011-01-20 14:44:16 -08001176 bool "BUG() support" if EXPERT
Matt Mackallc8538a72005-05-01 08:59:01 -07001177 default y
1178 help
1179 Disabling this option eliminates support for BUG and WARN, reducing
1180 the size of your kernel image and potentially quietly ignoring
1181 numerous fatal conditions. You should only consider disabling this
1182 option for embedded systems with no facilities for reporting errors.
1183 Just say Y.
1184
Matt Mackall708e9a72006-01-08 01:05:25 -08001185config ELF_CORE
1186 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001187 bool "Enable ELF core dumps" if EXPERT
Matt Mackall708e9a72006-01-08 01:05:25 -08001188 help
1189 Enable support for generating core dumps. Disabling saves about 4k.
1190
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001191
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +02001192config PCSPKR_PLATFORM
David Rientjes6a108a12011-01-20 14:44:16 -08001193 bool "Enable PC-Speaker support" if EXPERT
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001194 depends on HAVE_PCSPKR_PLATFORM
Ralf Baechle15f304b2011-06-01 19:04:59 +01001195 select I8253_LOCK
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +02001196 default y
1197 help
1198 This option allows to disable the internal PC-Speaker
1199 support, saving some memory.
1200
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001201config HAVE_PCSPKR_PLATFORM
1202 bool
1203
Linus Torvalds1da177e2005-04-16 15:20:36 -07001204config BASE_FULL
1205 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001206 bool "Enable full-sized data structures for core" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001207 help
1208 Disabling this option reduces the size of miscellaneous core
1209 kernel data structures. This saves memory on small machines,
1210 but may reduce performance.
1211
1212config FUTEX
David Rientjes6a108a12011-01-20 14:44:16 -08001213 bool "Enable futex support" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001214 default y
Ingo Molnar23f78d4a2006-06-27 02:54:53 -07001215 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001216 help
1217 Disabling this option will cause the kernel to be built without
1218 support for "fast userspace mutexes". The resulting kernel may not
1219 run glibc-based applications correctly.
1220
1221config EPOLL
David Rientjes6a108a12011-01-20 14:44:16 -08001222 bool "Enable eventpoll support" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001223 default y
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001224 select ANON_INODES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001225 help
1226 Disabling this option will cause the kernel to be built without
1227 support for epoll family of system calls.
1228
Davide Libenzifba2afa2007-05-10 22:23:13 -07001229config SIGNALFD
David Rientjes6a108a12011-01-20 14:44:16 -08001230 bool "Enable signalfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001231 select ANON_INODES
Davide Libenzifba2afa2007-05-10 22:23:13 -07001232 default y
1233 help
1234 Enable the signalfd() system call that allows to receive signals
1235 on a file descriptor.
1236
1237 If unsure, say Y.
1238
Davide Libenzib215e282007-05-10 22:23:16 -07001239config TIMERFD
David Rientjes6a108a12011-01-20 14:44:16 -08001240 bool "Enable timerfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001241 select ANON_INODES
Davide Libenzib215e282007-05-10 22:23:16 -07001242 default y
1243 help
1244 Enable the timerfd() system call that allows to receive timer
1245 events on a file descriptor.
1246
1247 If unsure, say Y.
1248
Davide Libenzie1ad7462007-05-10 22:23:19 -07001249config EVENTFD
David Rientjes6a108a12011-01-20 14:44:16 -08001250 bool "Enable eventfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001251 select ANON_INODES
Davide Libenzie1ad7462007-05-10 22:23:19 -07001252 default y
1253 help
1254 Enable the eventfd() system call that allows to receive both
1255 kernel notification (ie. KAIO) or userspace notifications.
1256
1257 If unsure, say Y.
1258
Linus Torvalds1da177e2005-04-16 15:20:36 -07001259config SHMEM
David Rientjes6a108a12011-01-20 14:44:16 -08001260 bool "Use full shmem filesystem" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001261 default y
1262 depends on MMU
1263 help
1264 The shmem is an internal filesystem used to manage shared memory.
1265 It is backed by swap and manages resource limits. It is also exported
1266 to userspace as tmpfs if TMPFS is enabled. Disabling this
1267 option replaces shmem and tmpfs with the much simpler ramfs code,
1268 which may be appropriate on small systems without swap.
1269
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001270config AIO
David Rientjes6a108a12011-01-20 14:44:16 -08001271 bool "Enable AIO support" if EXPERT
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001272 default y
1273 help
1274 This option enables POSIX asynchronous I/O which may by used
1275 by some high performance threaded applications. Disabling
1276 this option saves about 7k.
1277
Randy Dunlap6befe5f2011-04-26 12:33:21 -07001278config EMBEDDED
1279 bool "Embedded system"
1280 select EXPERT
1281 help
1282 This option should be enabled if compiling the kernel for
1283 an embedded system so certain expert options are available
1284 for configuration.
1285
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001286config HAVE_PERF_EVENTS
Thomas Gleixner0793a612008-12-04 20:12:29 +01001287 bool
Mike Frysinger018df722009-06-12 13:17:43 -04001288 help
1289 See tools/perf/design.txt for details.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001290
Peter Zijlstra906010b2009-09-21 16:08:49 +02001291config PERF_USE_VMALLOC
1292 bool
1293 help
1294 See tools/perf/design.txt for details
1295
Ingo Molnar57c0c152009-09-21 12:20:38 +02001296menu "Kernel Performance Events And Counters"
Thomas Gleixner0793a612008-12-04 20:12:29 +01001297
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001298config PERF_EVENTS
Ingo Molnar57c0c152009-09-21 12:20:38 +02001299 bool "Kernel performance events and counters"
1300 default y if (PROFILING || PERF_COUNTERS)
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001301 depends on HAVE_PERF_EVENTS
Ingo Molnar4c59e462008-12-08 19:38:33 +01001302 select ANON_INODES
Peter Zijlstrae360adb2010-10-14 14:01:34 +08001303 select IRQ_WORK
Thomas Gleixner0793a612008-12-04 20:12:29 +01001304 help
Ingo Molnar57c0c152009-09-21 12:20:38 +02001305 Enable kernel support for various performance events provided
1306 by software and hardware.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001307
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001308 Software events are supported either built-in or via the
Ingo Molnar57c0c152009-09-21 12:20:38 +02001309 use of generic tracepoints.
1310
1311 Most modern CPUs support performance events via performance
1312 counter registers. These registers count the number of certain
Thomas Gleixner0793a612008-12-04 20:12:29 +01001313 types of hw events: such as instructions executed, cachemisses
1314 suffered, or branches mis-predicted - without slowing down the
1315 kernel or applications. These registers can also trigger interrupts
1316 when a threshold number of events have passed - and can thus be
1317 used to profile the code that runs on that CPU.
1318
Ingo Molnar57c0c152009-09-21 12:20:38 +02001319 The Linux Performance Event subsystem provides an abstraction of
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001320 these software and hardware event capabilities, available via a
Ingo Molnar57c0c152009-09-21 12:20:38 +02001321 system call and used by the "perf" utility in tools/perf/. It
Thomas Gleixner0793a612008-12-04 20:12:29 +01001322 provides per task and per CPU counters, and it provides event
1323 capabilities on top of those.
1324
1325 Say Y if unsure.
1326
Ingo Molnar57c0c152009-09-21 12:20:38 +02001327config PERF_COUNTERS
1328 bool "Kernel performance counters (old config option)"
1329 depends on HAVE_PERF_EVENTS
1330 help
1331 This config has been obsoleted by the PERF_EVENTS
1332 config option - please see that one for details.
1333
1334 It has no effect on the kernel whether you enable
1335 it or not, it is a compatibility placeholder.
1336
1337 Say N if unsure.
1338
Peter Zijlstra906010b2009-09-21 16:08:49 +02001339config DEBUG_PERF_USE_VMALLOC
1340 default n
1341 bool "Debug: use vmalloc to back perf mmap() buffers"
1342 depends on PERF_EVENTS && DEBUG_KERNEL
1343 select PERF_USE_VMALLOC
1344 help
1345 Use vmalloc memory to back perf mmap() buffers.
1346
1347 Mostly useful for debugging the vmalloc code on platforms
1348 that don't require it.
1349
1350 Say N if unsure.
1351
Thomas Gleixner0793a612008-12-04 20:12:29 +01001352endmenu
1353
Christoph Lameterf8891e52006-06-30 01:55:45 -07001354config VM_EVENT_COUNTERS
1355 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001356 bool "Enable VM event counters for /proc/vmstat" if EXPERT
Christoph Lameterf8891e52006-06-30 01:55:45 -07001357 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001358 VM event counters are needed for event counts to be shown.
1359 This option allows the disabling of the VM event counters
David Rientjes6a108a12011-01-20 14:44:16 -08001360 on EXPERT systems. /proc/vmstat will only show page counts
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001361 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -07001362
Thomas Petazzoni3d137312008-08-19 10:28:24 +02001363config PCI_QUIRKS
1364 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001365 bool "Enable PCI quirk workarounds" if EXPERT
Geert Uytterhoeven61cfc7e2008-10-22 08:53:25 +02001366 depends on PCI
Thomas Petazzoni3d137312008-08-19 10:28:24 +02001367 help
1368 This enables workarounds for various PCI chipset
1369 bugs/quirks. Disable this only if your target machine is
1370 unaffected by PCI quirks.
1371
Christoph Lameter41ecc552007-05-09 02:32:44 -07001372config SLUB_DEBUG
1373 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001374 bool "Enable SLUB debugging support" if EXPERT
Christoph Lameterf6acb632008-04-29 16:16:06 -07001375 depends on SLUB && SYSFS
Christoph Lameter41ecc552007-05-09 02:32:44 -07001376 help
1377 SLUB has extensive debug support features. Disabling these can
1378 result in significant savings in code size. This also disables
1379 SLUB sysfs support. /sys/slab will not exist and there will be
1380 no support for cache validation etc.
1381
Randy Dunlapb943c462009-03-10 12:55:46 -07001382config COMPAT_BRK
1383 bool "Disable heap randomization"
1384 default y
1385 help
1386 Randomizing heap placement makes heap exploits harder, but it
1387 also breaks ancient binaries (including anything libc5 based).
1388 This option changes the bootup default to heap randomization
Matt LaPlante692105b2009-01-26 11:12:25 +01001389 disabled, and can be overridden at runtime by setting
Randy Dunlapb943c462009-03-10 12:55:46 -07001390 /proc/sys/kernel/randomize_va_space to 2.
1391
1392 On non-ancient distros (post-2000 ones) N is usually a safe choice.
1393
Christoph Lameter81819f02007-05-06 14:49:36 -07001394choice
1395 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -07001396 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001397 help
1398 This option allows to select a slab allocator.
1399
1400config SLAB
1401 bool "SLAB"
1402 help
1403 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -07001404 well in all environments. It organizes cache hot objects in
Simon Arlott02f56212008-11-05 22:18:19 +00001405 per cpu and per node queues.
Christoph Lameter81819f02007-05-06 14:49:36 -07001406
1407config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001408 bool "SLUB (Unqueued Allocator)"
1409 help
1410 SLUB is a slab allocator that minimizes cache line usage
1411 instead of managing queues of cached objects (SLAB approach).
1412 Per cpu caching is realized using slabs of objects instead
1413 of queues of objects. SLUB can use memory efficiently
Simon Arlott02f56212008-11-05 22:18:19 +00001414 and has enhanced diagnostics. SLUB is the default choice for
1415 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -07001416
1417config SLOB
David Rientjes6a108a12011-01-20 14:44:16 -08001418 depends on EXPERT
Christoph Lameter81819f02007-05-06 14:49:36 -07001419 bool "SLOB (Simple Allocator)"
1420 help
Matt Mackall37291452008-02-04 22:29:38 -08001421 SLOB replaces the stock allocator with a drastically simpler
1422 allocator. SLOB is generally more space efficient but
1423 does not perform as well on large systems.
Christoph Lameter81819f02007-05-06 14:49:36 -07001424
1425endchoice
1426
Jie Zhangea637632009-12-14 18:00:02 -08001427config MMAP_ALLOW_UNINITIALIZED
1428 bool "Allow mmapped anonymous memory to be uninitialized"
David Rientjes6a108a12011-01-20 14:44:16 -08001429 depends on EXPERT && !MMU
Jie Zhangea637632009-12-14 18:00:02 -08001430 default n
1431 help
1432 Normally, and according to the Linux spec, anonymous memory obtained
1433 from mmap() has it's contents cleared before it is passed to
1434 userspace. Enabling this config option allows you to request that
1435 mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus
1436 providing a huge performance boost. If this option is not enabled,
1437 then the flag will be ignored.
1438
1439 This is taken advantage of by uClibc's malloc(), and also by
1440 ELF-FDPIC binfmt's brk and stack allocator.
1441
1442 Because of the obvious security issues, this option should only be
1443 enabled on embedded devices where you control what is run in
1444 userspace. Since that isn't generally a problem on no-MMU systems,
1445 it is normally safe to say Y here.
1446
1447 See Documentation/nommu-mmap.txt for more information.
1448
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001449config PROFILING
Robert Richterb309a292010-02-26 15:01:23 +01001450 bool "Profiling support"
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001451 help
1452 Say Y here to enable the extended profiling support mechanisms used
1453 by profilers such as OProfile.
1454
Ingo Molnar5f87f112008-07-23 14:15:22 +02001455#
1456# Place an empty function call at each tracepoint site. Can be
1457# dynamically changed for a probe function.
1458#
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001459config TRACEPOINTS
Ingo Molnar5f87f112008-07-23 14:15:22 +02001460 bool
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001461
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -05001462source "arch/Kconfig"
1463
Linus Torvalds1da177e2005-04-16 15:20:36 -07001464endmenu # General setup
1465
Dmitry Baryshkovee7e5512008-06-29 14:18:46 +04001466config HAVE_GENERIC_DMA_COHERENT
1467 bool
1468 default n
1469
Linus Torvalds158a9622008-01-02 13:04:48 -08001470config SLABINFO
1471 bool
1472 depends on PROC_FS
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001473 depends on SLAB || SLUB_DEBUG
Linus Torvalds158a9622008-01-02 13:04:48 -08001474 default y
1475
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001476config RT_MUTEXES
1477 boolean
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001478
Linus Torvalds1da177e2005-04-16 15:20:36 -07001479config BASE_SMALL
1480 int
1481 default 0 if BASE_FULL
1482 default 1 if !BASE_FULL
1483
Jan Engelhardt66da5732007-07-15 23:39:29 -07001484menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001485 bool "Enable loadable module support"
1486 help
1487 Kernel modules are small pieces of compiled code which can
1488 be inserted in the running kernel, rather than being
1489 permanently built into the kernel. You use the "modprobe"
1490 tool to add (and sometimes remove) them. If you say Y here,
1491 many parts of the kernel can be built as modules (by
1492 answering M instead of Y where indicated): this is most
1493 useful for infrequently used options which are not required
1494 for booting. For more information, see the man pages for
1495 modprobe, lsmod, modinfo, insmod and rmmod.
1496
1497 If you say Y here, you will need to run "make
1498 modules_install" to put the modules under /lib/modules/
1499 where modprobe can find them (you may need to be root to do
1500 this).
1501
1502 If unsure, say Y.
1503
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001504if MODULES
1505
Linus Torvalds826e4502008-05-04 17:04:16 -07001506config MODULE_FORCE_LOAD
1507 bool "Forced module loading"
Linus Torvalds826e4502008-05-04 17:04:16 -07001508 default n
1509 help
Rusty Russell91e37a72008-05-09 16:25:28 +10001510 Allow loading of modules without version information (ie. modprobe
1511 --force). Forced module loading sets the 'F' (forced) taint flag and
1512 is usually a really bad idea.
Linus Torvalds826e4502008-05-04 17:04:16 -07001513
Linus Torvalds1da177e2005-04-16 15:20:36 -07001514config MODULE_UNLOAD
1515 bool "Module unloading"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001516 help
1517 Without this option you will not be able to unload any
1518 modules (note that some modules may not be unloadable
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001519 anyway), which makes your kernel smaller, faster
1520 and simpler. If unsure, say Y.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001521
1522config MODULE_FORCE_UNLOAD
1523 bool "Forced module unloading"
1524 depends on MODULE_UNLOAD && EXPERIMENTAL
1525 help
1526 This option allows you to force a module to unload, even if the
1527 kernel believes it is unsafe: the kernel will remove the module
1528 without waiting for anyone to stop using it (using the -f option to
1529 rmmod). This is mainly for kernel developers and desperate users.
1530 If unsure, say N.
1531
Linus Torvalds1da177e2005-04-16 15:20:36 -07001532config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +01001533 bool "Module versioning support"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001534 help
1535 Usually, you have to use modules compiled with your kernel.
1536 Saying Y here makes it sometimes possible to use modules
1537 compiled for different kernels, by adding enough information
1538 to the modules to (hopefully) spot any changes which would
1539 make them incompatible with the kernel you are running. If
1540 unsure, say N.
1541
1542config MODULE_SRCVERSION_ALL
1543 bool "Source checksum for all modules"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001544 help
1545 Modules which contain a MODULE_VERSION get an extra "srcversion"
1546 field inserted into their modinfo section, which contains a
1547 sum of the source files which made it. This helps maintainers
1548 see exactly which source was used to build a module (since
1549 others sometimes change the module source without updating
1550 the version). With this option, such a "srcversion" field
1551 will be created for all modules. If unsure, say N.
1552
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001553endif # MODULES
1554
Rusty Russell98a79d62008-12-13 21:19:41 +10301555config INIT_ALL_POSSIBLE
1556 bool
1557 help
1558 Back when each arch used to define their own cpu_online_map and
1559 cpu_possible_map, some of them chose to initialize cpu_possible_map
1560 with all 1s, and others with all 0s. When they were centralised,
1561 it was better to provide this option than to break all the archs
Matt LaPlante692105b2009-01-26 11:12:25 +01001562 and have several arch maintainers pursuing me down dark alleys.
Rusty Russell98a79d62008-12-13 21:19:41 +10301563
Linus Torvalds1da177e2005-04-16 15:20:36 -07001564config STOP_MACHINE
1565 bool
1566 default y
1567 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
1568 help
1569 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001570
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001571source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -07001572
1573config PREEMPT_NOTIFIERS
1574 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +01001575
Steffen Klassert16295be2010-01-06 19:47:10 +11001576config PADATA
1577 depends on SMP
1578 bool
1579
Thomas Gleixner6beb0002009-11-09 15:21:34 +00001580source "kernel/Kconfig.locks"