blob: fed81b576f29ad8003c48ed293bb9cd42bd95922 [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 IRQ_WORK
24 bool
Peter Zijlstrae360adb2010-10-14 14:01:34 +080025
David Daney1dbdc6f2012-04-19 14:59:57 -070026config BUILDTIME_EXTABLE_SORT
27 bool
28
Al Boldiff0cfc62007-07-31 00:39:23 -070029menu "General setup"
Linus Torvalds1da177e2005-04-16 15:20:36 -070030
Linus Torvalds1da177e2005-04-16 15:20:36 -070031config BROKEN
32 bool
Linus Torvalds1da177e2005-04-16 15:20:36 -070033
34config BROKEN_ON_SMP
35 bool
36 depends on BROKEN || !SMP
37 default y
38
Linus Torvalds1da177e2005-04-16 15:20:36 -070039config INIT_ENV_ARG_LIMIT
40 int
Adrian Bunkdd673bc2006-06-30 01:55:51 -070041 default 32 if !UML
42 default 128 if UML
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 help
Randy Dunlap34ad92c2005-10-30 15:01:46 -080044 Maximum of each of the number of arguments and environment
45 variables passed to init from the kernel command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
Roland McGrath84336462009-12-21 16:24:06 -080048config CROSS_COMPILE
49 string "Cross-compiler tool prefix"
50 help
51 Same as running 'make CROSS_COMPILE=prefix-' but stored for
52 default make runs in this kernel build directory. You don't
53 need to set this unless you want the configured kernel build
54 directory to select the cross-compiler automatically.
55
Jiri Slaby4bb16672013-05-22 10:56:24 +020056config COMPILE_TEST
57 bool "Compile also drivers which will not load"
58 default n
59 help
60 Some drivers can be compiled on a different platform than they are
61 intended to be run on. Despite they cannot be loaded there (or even
62 when they load they cannot be used due to missing HW support),
63 developers still, opposing to distributors, might want to build such
64 drivers to compile-test them.
65
66 If you are a developer and want to build everything available, say Y
67 here. If you are a user/distributor, say N here to exclude useless
68 drivers to be distributed.
69
Linus Torvalds1da177e2005-04-16 15:20:36 -070070config LOCALVERSION
71 string "Local version - append to kernel release"
72 help
73 Append an extra string to the end of your kernel version.
74 This will show up when you type uname, for example.
75 The string you set here will be appended after the contents of
76 any files with a filename matching localversion* in your
77 object and source tree, in that order. Your total string can
78 be a maximum of 64 characters.
79
Ryan Andersonaaebf432005-07-31 04:57:49 -040080config LOCALVERSION_AUTO
81 bool "Automatically append version information to the version string"
82 default y
83 help
84 This will try to automatically determine if the current tree is a
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020085 release tree by looking for git tags that belong to the current
86 top of tree revision.
Ryan Andersonaaebf432005-07-31 04:57:49 -040087
88 A string of the format -gxxxxxxxx will be added to the localversion
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020089 if a git-based tree is found. The string generated by this will be
Ryan Andersonaaebf432005-07-31 04:57:49 -040090 appended after any matching localversion* files, and after the value
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020091 set in CONFIG_LOCALVERSION.
Ryan Andersonaaebf432005-07-31 04:57:49 -040092
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020093 (The actual string used here is the first eight characters produced
94 by running the command:
95
96 $ git rev-parse --verify HEAD
97
98 which is done within the script "scripts/setlocalversion".)
Ryan Andersonaaebf432005-07-31 04:57:49 -040099
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800100config HAVE_KERNEL_GZIP
101 bool
102
103config HAVE_KERNEL_BZIP2
104 bool
105
106config HAVE_KERNEL_LZMA
107 bool
108
Lasse Collin3ebe1242011-01-12 17:01:23 -0800109config HAVE_KERNEL_XZ
110 bool
111
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800112config HAVE_KERNEL_LZO
113 bool
114
Kyungsik Leee76e1fd2013-07-08 16:01:46 -0700115config HAVE_KERNEL_LZ4
116 bool
117
Alain Knaff30d65db2009-01-04 22:46:17 +0100118choice
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800119 prompt "Kernel compression mode"
120 default KERNEL_GZIP
Kyungsik Leee76e1fd2013-07-08 16:01:46 -0700121 depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800122 help
Alain Knaff30d65db2009-01-04 22:46:17 +0100123 The linux kernel is a kind of self-extracting executable.
124 Several compression algorithms are available, which differ
125 in efficiency, compression and decompression speed.
126 Compression speed is only relevant when building a kernel.
127 Decompression speed is relevant at each boot.
128
129 If you have any problems with bzip2 or lzma compressed
130 kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
131 version of this functionality (bzip2 only), for 2.4, was
132 supplied by Christian Ludwig)
133
134 High compression options are mostly useful for users, who
135 are low on disk space (embedded systems), but for whom ram
136 size matters less.
137
138 If in doubt, select 'gzip'
139
140config KERNEL_GZIP
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800141 bool "Gzip"
142 depends on HAVE_KERNEL_GZIP
143 help
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800144 The old and tried gzip compression. It provides a good balance
145 between compression ratio and decompression speed.
Alain Knaff30d65db2009-01-04 22:46:17 +0100146
147config KERNEL_BZIP2
148 bool "Bzip2"
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800149 depends on HAVE_KERNEL_BZIP2
Alain Knaff30d65db2009-01-04 22:46:17 +0100150 help
151 Its compression ratio and speed is intermediate.
Randy Dunlap0a4dd352012-05-31 16:26:46 -0700152 Decompression speed is slowest among the choices. The kernel
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800153 size is about 10% smaller with bzip2, in comparison to gzip.
154 Bzip2 uses a large amount of memory. For modern kernels you
155 will need at least 8MB RAM or more for booting.
Alain Knaff30d65db2009-01-04 22:46:17 +0100156
157config KERNEL_LZMA
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800158 bool "LZMA"
159 depends on HAVE_KERNEL_LZMA
160 help
Randy Dunlap0a4dd352012-05-31 16:26:46 -0700161 This compression algorithm's ratio is best. Decompression speed
162 is between gzip and bzip2. Compression is slowest.
163 The kernel size is about 33% smaller with LZMA in comparison to gzip.
Alain Knaff30d65db2009-01-04 22:46:17 +0100164
Lasse Collin3ebe1242011-01-12 17:01:23 -0800165config KERNEL_XZ
166 bool "XZ"
167 depends on HAVE_KERNEL_XZ
168 help
169 XZ uses the LZMA2 algorithm and instruction set specific
170 BCJ filters which can improve compression ratio of executable
171 code. The size of the kernel is about 30% smaller with XZ in
172 comparison to gzip. On architectures for which there is a BCJ
173 filter (i386, x86_64, ARM, IA-64, PowerPC, and SPARC), XZ
174 will create a few percent smaller kernel than plain LZMA.
175
176 The speed is about the same as with LZMA: The decompression
177 speed of XZ is better than that of bzip2 but worse than gzip
178 and LZO. Compression is slow.
179
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800180config KERNEL_LZO
181 bool "LZO"
182 depends on HAVE_KERNEL_LZO
183 help
Randy Dunlap0a4dd352012-05-31 16:26:46 -0700184 Its compression ratio is the poorest among the choices. The kernel
Stephan Sperber681b3042010-07-14 11:23:08 +0200185 size is about 10% bigger than gzip; however its speed
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800186 (both compression and decompression) is the fastest.
187
Kyungsik Leee76e1fd2013-07-08 16:01:46 -0700188config KERNEL_LZ4
189 bool "LZ4"
190 depends on HAVE_KERNEL_LZ4
191 help
192 LZ4 is an LZ77-type compressor with a fixed, byte-oriented encoding.
193 A preliminary version of LZ4 de/compression tool is available at
194 <https://code.google.com/p/lz4/>.
195
196 Its compression ratio is worse than LZO. The size of the kernel
197 is about 8% bigger than LZO. But the decompression speed is
198 faster than LZO.
199
Alain Knaff30d65db2009-01-04 22:46:17 +0100200endchoice
201
Josh Triplettbd5dc172011-06-15 15:08:28 -0700202config DEFAULT_HOSTNAME
203 string "Default hostname"
204 default "(none)"
205 help
206 This option determines the default system hostname before userspace
207 calls sethostname(2). The kernel traditionally uses "(none)" here,
208 but you may wish to use a different default here to make a minimal
209 system more usable with less configuration.
210
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211config SWAP
212 bool "Support for paging of anonymous memory (swap)"
David Howells93614012006-09-30 20:45:40 +0200213 depends on MMU && BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214 default y
215 help
216 This option allows you to choose whether you want to have support
Jesper Juhl92c35042006-01-15 02:40:08 +0100217 for so called swap devices or swap files in your kernel that are
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 used to provide more virtual memory than the actual RAM present
219 in your computer. If unsure say Y.
220
221config SYSVIPC
222 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223 ---help---
224 Inter Process Communication is a suite of library functions and
225 system calls which let processes (running programs) synchronize and
226 exchange information. It is generally considered to be a good thing,
227 and some programs won't run unless you say Y here. In particular, if
228 you want to run the DOS emulator dosemu under Linux (read the
229 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
230 you'll need to say Y here.
231
232 You can find documentation about IPC with "info ipc" and also in
233 section 6.4 of the Linux Programmer's Guide, available from
234 <http://www.tldp.org/guides.html>.
235
Eric W. Biedermana5494dc2007-02-14 00:34:06 -0800236config SYSVIPC_SYSCTL
237 bool
238 depends on SYSVIPC
239 depends on SYSCTL
240 default y
241
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242config POSIX_MQUEUE
243 bool "POSIX Message Queues"
Kees Cook19c92392012-10-02 11:19:29 -0700244 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245 ---help---
246 POSIX variant of message queues is a part of IPC. In POSIX message
247 queues every message has a priority which decides about succession
248 of receiving it by a process. If you want to compile and run
249 programs written e.g. for Solaris with use of its POSIX message
Robert P. J. Dayb0e37652007-05-09 07:25:13 +0200250 queues (functions mq_*) say Y here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251
252 POSIX message queues are visible as a filesystem called 'mqueue'
253 and can be mounted somewhere if you want to do filesystem
254 operations on message queues.
255
256 If unsure, say Y.
257
Serge E. Hallynbdc8e5f2009-04-06 19:01:11 -0700258config POSIX_MQUEUE_SYSCTL
259 bool
260 depends on POSIX_MQUEUE
261 depends on SYSCTL
262 default y
263
Aneesh Kumar K.V990d6c22011-01-29 18:43:26 +0530264config FHANDLE
265 bool "open by fhandle syscalls"
266 select EXPORTFS
267 help
268 If you say Y here, a user level program will be able to map
269 file names to handle and then later use the handle for
270 different file system operations. This is useful in implementing
271 userspace file servers, which now track files using handles instead
272 of names. The handle would remain the same even if file names
273 get renamed. Enables open_by_handle_at(2) and name_to_handle_at(2)
274 syscalls.
275
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276config AUDIT
277 bool "Auditing support"
Chris Wright804a6a492005-05-11 10:52:45 +0100278 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 help
280 Enable auditing infrastructure that can be used with another
281 kernel subsystem, such as SELinux (which requires this for
282 logging of avc messages output). Does not do system-call
283 auditing without CONFIG_AUDITSYSCALL.
284
285config AUDITSYSCALL
286 bool "Enable system-call auditing support"
Will Deacon8f827a12012-07-06 15:48:16 +0100287 depends on AUDIT && (X86 || PPC || S390 || IA64 || UML || SPARC64 || SUPERH || (ARM && AEABI && !OABI_COMPAT))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 default y if SECURITY_SELINUX
289 help
290 Enable low-overhead system-call auditing infrastructure that
291 can be used independently or with another kernel subsystem,
Eric Paris67640b62009-12-17 20:12:06 -0500292 such as SELinux.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293
Eric Paris939a67f2009-12-17 20:12:06 -0500294config AUDIT_WATCH
295 def_bool y
296 depends on AUDITSYSCALL
297 select FSNOTIFY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298
Al Viro74c3cbe2007-07-22 08:04:18 -0400299config AUDIT_TREE
300 def_bool y
Eric Paris63c882a2009-05-21 17:02:01 -0400301 depends on AUDITSYSCALL
Eric Paris28a3a7e2009-12-17 20:12:05 -0500302 select FSNOTIFY
Al Viro74c3cbe2007-07-22 08:04:18 -0400303
Eric Paris633b4542012-01-03 14:23:08 -0500304config AUDIT_LOGINUID_IMMUTABLE
305 bool "Make audit loginuid immutable"
306 depends on AUDIT
307 help
Linus Torvaldsf429ee32012-01-17 16:06:51 -0800308 The config option toggles if a task setting its loginuid requires
Eric Paris633b4542012-01-03 14:23:08 -0500309 CAP_SYS_AUDITCONTROL or if that task should require no special permissions
310 but should instead only allow setting its loginuid if it was never
311 previously set. On systems which use systemd or a similar central
312 process to restart login services this should be set to true. On older
313 systems in which an admin would typically have to directly stop and
314 start processes this should be set to false. Setting this to true allows
315 one to drop potentially dangerous capabilites from the login tasks,
316 but may not be backwards compatible with older init systems.
317
Thomas Gleixnerd9817eb2010-09-27 12:45:59 +0000318source "kernel/irq/Kconfig"
Thomas Gleixner764e0da2012-05-21 23:16:18 +0200319source "kernel/time/Kconfig"
Thomas Gleixnerd9817eb2010-09-27 12:45:59 +0000320
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200321menu "CPU/Task time and stats accounting"
322
Frederic Weisbeckerabf917c2012-07-25 07:56:04 +0200323config VIRT_CPU_ACCOUNTING
324 bool
325
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200326choice
327 prompt "Cputime accounting"
328 default TICK_CPU_ACCOUNTING if !PPC64
Stephen Rothwell02fc8d32013-02-08 14:19:38 +1100329 default VIRT_CPU_ACCOUNTING_NATIVE if PPC64
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200330
331# Kind of a stub config for the pure tick based cputime accounting
332config TICK_CPU_ACCOUNTING
333 bool "Simple tick based cputime accounting"
Frederic Weisbeckerc58b0df2013-04-26 15:16:31 +0200334 depends on !S390 && !NO_HZ_FULL
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200335 help
336 This is the basic tick based cputime accounting that maintains
337 statistics about user, system and idle time spent on per jiffies
338 granularity.
339
340 If unsure, say Y.
341
Frederic Weisbeckerabf917c2012-07-25 07:56:04 +0200342config VIRT_CPU_ACCOUNTING_NATIVE
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200343 bool "Deterministic task and CPU time accounting"
Frederic Weisbeckerc58b0df2013-04-26 15:16:31 +0200344 depends on HAVE_VIRT_CPU_ACCOUNTING && !NO_HZ_FULL
Frederic Weisbeckerabf917c2012-07-25 07:56:04 +0200345 select VIRT_CPU_ACCOUNTING
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200346 help
347 Select this option to enable more accurate task and CPU time
348 accounting. This is done by reading a CPU counter on each
349 kernel entry and exit and on transitions within the kernel
350 between system, softirq and hardirq state, so there is a
351 small performance impact. In the case of s390 or IBM POWER > 5,
352 this also enables accounting of stolen time on logically-partitioned
353 systems.
354
Frederic Weisbeckerabf917c2012-07-25 07:56:04 +0200355config VIRT_CPU_ACCOUNTING_GEN
356 bool "Full dynticks CPU time accounting"
357 depends on HAVE_CONTEXT_TRACKING && 64BIT
358 select VIRT_CPU_ACCOUNTING
359 select CONTEXT_TRACKING
360 help
361 Select this option to enable task and CPU time accounting on full
362 dynticks systems. This accounting is implemented by watching every
363 kernel-user boundaries using the context tracking subsystem.
364 The accounting is thus performed at the expense of some significant
365 overhead.
366
367 For now this is only useful if you are working on the full
368 dynticks subsystem development.
369
370 If unsure, say N.
371
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200372config IRQ_TIME_ACCOUNTING
373 bool "Fine granularity task level IRQ time accounting"
Frederic Weisbeckerc58b0df2013-04-26 15:16:31 +0200374 depends on HAVE_IRQ_TIME_ACCOUNTING && !NO_HZ_FULL
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200375 help
376 Select this option to enable fine granularity task irq time
377 accounting. This is done by reading a timestamp on each
378 transitions between softirq and hardirq state, so there can be a
379 small performance impact.
380
381 If in doubt, say N here.
382
383endchoice
384
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200385config BSD_PROCESS_ACCT
386 bool "BSD Process Accounting"
387 help
388 If you say Y here, a user level program will be able to instruct the
389 kernel (via a special system call) to write process accounting
390 information to a file: whenever a process exits, information about
391 that process will be appended to the file by the kernel. The
392 information includes things such as creation time, owning user,
393 command name, memory usage, controlling terminal etc. (the complete
394 list is in the struct acct in <file:include/linux/acct.h>). It is
395 up to the user level program to do useful things with this
396 information. This is generally a good idea, so say Y.
397
398config BSD_PROCESS_ACCT_V3
399 bool "BSD Process Accounting version 3 file format"
400 depends on BSD_PROCESS_ACCT
401 default n
402 help
403 If you say Y here, the process accounting information is written
404 in a new file format that also logs the process IDs of each
405 process and it's parent. Note that this file format is incompatible
406 with previous v0/v1/v2 file formats, so you will need updated tools
407 for processing it. A preliminary version of these tools is available
408 at <http://www.gnu.org/software/acct/>.
409
410config TASKSTATS
Kees Cook19c92392012-10-02 11:19:29 -0700411 bool "Export task/process statistics through netlink"
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200412 depends on NET
413 default n
414 help
415 Export selected statistics for tasks/processes through the
416 generic netlink interface. Unlike BSD process accounting, the
417 statistics are available during the lifetime of tasks/processes as
418 responses to commands. Like BSD accounting, they are sent to user
419 space on task exit.
420
421 Say N if unsure.
422
423config TASK_DELAY_ACCT
Kees Cook19c92392012-10-02 11:19:29 -0700424 bool "Enable per-task delay accounting"
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200425 depends on TASKSTATS
426 help
427 Collect information on time spent by a task waiting for system
428 resources like cpu, synchronous block I/O completion and swapping
429 in pages. Such statistics can help in setting a task's priorities
430 relative to other tasks for cpu, io, rss limits etc.
431
432 Say N if unsure.
433
434config TASK_XACCT
Kees Cook19c92392012-10-02 11:19:29 -0700435 bool "Enable extended accounting over taskstats"
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200436 depends on TASKSTATS
437 help
438 Collect extended task accounting data and send the data
439 to userland for processing over the taskstats interface.
440
441 Say N if unsure.
442
443config TASK_IO_ACCOUNTING
Kees Cook19c92392012-10-02 11:19:29 -0700444 bool "Enable per-task storage I/O accounting"
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200445 depends on TASK_XACCT
446 help
447 Collect information on the number of bytes of storage I/O which this
448 task has caused.
449
450 Say N if unsure.
451
452endmenu # "CPU/Task time and stats accounting"
453
Mike Travisc903ff82009-01-15 12:28:29 -0800454menu "RCU Subsystem"
455
456choice
457 prompt "RCU Implementation"
Paul E. McKenney31c9a242009-04-02 21:06:25 -0700458 default TREE_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800459
Mike Travisc903ff82009-01-15 12:28:29 -0800460config TREE_RCU
461 bool "Tree-based hierarchical RCU"
Paul E. McKenney687d7a92010-07-21 06:52:40 -0700462 depends on !PREEMPT && SMP
Steven Rostedt016a8d52013-05-28 17:32:53 -0400463 select IRQ_WORK
Mike Travisc903ff82009-01-15 12:28:29 -0800464 help
465 This option selects the RCU implementation that is
466 designed for very large SMP system with hundreds or
Paul E. McKenneyc17ef452009-06-23 17:12:47 -0700467 thousands of CPUs. It also scales down nicely to
468 smaller systems.
Mike Travisc903ff82009-01-15 12:28:29 -0800469
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700470config TREE_PREEMPT_RCU
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700471 bool "Preemptible tree-based hierarchical RCU"
Paul E. McKenney9fc52d82013-01-08 15:48:33 -0800472 depends on PREEMPT
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700473 help
474 This option selects the RCU implementation that is
475 designed for very large SMP systems with hundreds or
476 thousands of CPUs, but for which real-time response
Paul E. McKenneybbe3eae2009-09-13 09:15:08 -0700477 is also required. It also scales down nicely to
478 smaller systems.
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700479
Paul E. McKenney9fc52d82013-01-08 15:48:33 -0800480 Select this option if you are unsure.
481
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -0700482config TINY_RCU
483 bool "UP-only small-memory-footprint RCU"
Paul E. McKenney8008e122011-06-08 16:31:33 -0700484 depends on !PREEMPT && !SMP
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -0700485 help
486 This option selects the RCU implementation that is
487 designed for UP systems from which real-time response
488 is not required. This option greatly reduces the
489 memory footprint of RCU.
490
Mike Travisc903ff82009-01-15 12:28:29 -0800491endchoice
492
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700493config PREEMPT_RCU
Paul E. McKenney127781d2013-03-27 08:44:00 -0700494 def_bool TREE_PREEMPT_RCU
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700495 help
496 This option enables preemptible-RCU code that is common between
497 the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations.
498
Paul E. McKenney6bfc09e2012-10-19 12:49:17 -0700499config RCU_STALL_COMMON
500 def_bool ( TREE_RCU || TREE_PREEMPT_RCU || RCU_TRACE )
501 help
502 This option enables RCU CPU stall code that is common between
503 the TINY and TREE variants of RCU. The purpose is to allow
504 the tiny variants to disable RCU CPU stall warnings, while
505 making these warnings mandatory for the tree variants.
506
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100507config CONTEXT_TRACKING
508 bool
509
Frederic Weisbecker2b1d5022012-07-11 20:26:30 +0200510config RCU_USER_QS
511 bool "Consider userspace as in RCU extended quiescent state"
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100512 depends on HAVE_CONTEXT_TRACKING && SMP
513 select CONTEXT_TRACKING
Frederic Weisbecker2b1d5022012-07-11 20:26:30 +0200514 help
515 This option sets hooks on kernel / userspace boundaries and
516 puts RCU in extended quiescent state when the CPU runs in
517 userspace. It means that when a CPU runs in userspace, it is
518 excluded from the global RCU state machine and thus doesn't
Paul Gortmakeraf71bef2012-10-24 11:07:09 -0700519 try to keep the timer tick on for RCU.
Frederic Weisbecker2b1d5022012-07-11 20:26:30 +0200520
Frederic Weisbeckerd6771242012-10-11 01:48:28 +0200521 Unless you want to hack and help the development of the full
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100522 dynticks mode, you shouldn't enable this option. It also
Paul Gortmakeraf71bef2012-10-24 11:07:09 -0700523 adds unnecessary overhead.
Frederic Weisbeckerd6771242012-10-11 01:48:28 +0200524
525 If unsure say N
526
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100527config CONTEXT_TRACKING_FORCE
528 bool "Force context tracking"
529 depends on CONTEXT_TRACKING
Frederic Weisbecker8b438762013-02-26 15:37:59 +0100530 default CONTEXT_TRACKING
Frederic Weisbecker1fd2b442012-07-11 20:26:40 +0200531 help
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100532 Probe on user/kernel boundaries by default in order to
533 test the features that rely on it such as userspace RCU extended
534 quiescent states.
535 This test is there for debugging until we have a real user like the
536 full dynticks mode.
Frederic Weisbeckerd6771242012-10-11 01:48:28 +0200537
Mike Travisc903ff82009-01-15 12:28:29 -0800538config RCU_FANOUT
539 int "Tree-based hierarchical RCU fanout value"
540 range 2 64 if 64BIT
541 range 2 32 if !64BIT
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700542 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800543 default 64 if 64BIT
544 default 32 if !64BIT
545 help
546 This option controls the fanout of hierarchical implementations
547 of RCU, allowing RCU to work efficiently on machines with
Paul E. McKenney4d87ffa2010-08-04 17:31:12 -0700548 large numbers of CPUs. This value must be at least the fourth
549 root of NR_CPUS, which allows NR_CPUS to be insanely large.
550 The default value of RCU_FANOUT should be used for production
551 systems, but if you are stress-testing the RCU implementation
552 itself, small RCU_FANOUT values allow you to test large-system
553 code paths on small(er) systems.
Mike Travisc903ff82009-01-15 12:28:29 -0800554
555 Select a specific number if testing RCU itself.
556 Take the default if unsure.
557
Paul E. McKenney8932a632012-04-19 12:20:14 -0700558config RCU_FANOUT_LEAF
559 int "Tree-based hierarchical RCU leaf-level fanout value"
560 range 2 RCU_FANOUT if 64BIT
561 range 2 RCU_FANOUT if !64BIT
562 depends on TREE_RCU || TREE_PREEMPT_RCU
563 default 16
564 help
565 This option controls the leaf-level fanout of hierarchical
566 implementations of RCU, and allows trading off cache misses
567 against lock contention. Systems that synchronize their
568 scheduling-clock interrupts for energy-efficiency reasons will
569 want the default because the smaller leaf-level fanout keeps
570 lock contention levels acceptably low. Very large systems
571 (hundreds or thousands of CPUs) will instead want to set this
572 value to the maximum value possible in order to reduce the
573 number of cache misses incurred during RCU's grace-period
574 initialization. These systems tend to run CPU-bound, and thus
575 are not helped by synchronized interrupts, and thus tend to
576 skew them, which reduces lock contention enough that large
577 leaf-level fanouts work well.
578
579 Select a specific number if testing RCU itself.
580
581 Select the maximum permissible value for large systems.
582
583 Take the default if unsure.
584
Mike Travisc903ff82009-01-15 12:28:29 -0800585config RCU_FANOUT_EXACT
586 bool "Disable tree-based hierarchical RCU auto-balancing"
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700587 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800588 default n
589 help
590 This option forces use of the exact RCU_FANOUT value specified,
591 regardless of imbalances in the hierarchy. This is useful for
592 testing RCU itself, and might one day be useful on systems with
593 strong NUMA behavior.
594
595 Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
596
597 Say N if unsure.
598
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800599config RCU_FAST_NO_HZ
600 bool "Accelerate last non-dyntick-idle CPU's grace periods"
Frederic Weisbecker3451d022011-08-10 23:21:01 +0200601 depends on NO_HZ_COMMON && SMP
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800602 default n
603 help
Paul E. McKenneyc0f4dfd2012-12-28 11:30:36 -0800604 This option permits CPUs to enter dynticks-idle state even if
605 they have RCU callbacks queued, and prevents RCU from waking
606 these CPUs up more than roughly once every four jiffies (by
607 default, you can adjust this using the rcutree.rcu_idle_gp_delay
608 parameter), thus improving energy efficiency. On the other
609 hand, this option increases the duration of RCU grace periods,
610 for example, slowing down synchronize_rcu().
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800611
Paul E. McKenneyc0f4dfd2012-12-28 11:30:36 -0800612 Say Y if energy efficiency is critically important, and you
613 don't care about increased grace-period durations.
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800614
615 Say N if you are unsure.
616
Mike Travisc903ff82009-01-15 12:28:29 -0800617config TREE_RCU_TRACE
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700618 def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
Mike Travisc903ff82009-01-15 12:28:29 -0800619 select DEBUG_FS
620 help
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700621 This option provides tracing for the TREE_RCU and
622 TREE_PREEMPT_RCU implementations, permitting Makefile to
623 trivially select kernel/rcutree_trace.c.
Mike Travisc903ff82009-01-15 12:28:29 -0800624
Paul E. McKenney24278d12010-09-27 17:25:23 -0700625config RCU_BOOST
626 bool "Enable RCU priority boosting"
Paul E. McKenney27f4d282011-02-07 12:47:15 -0800627 depends on RT_MUTEXES && PREEMPT_RCU
Paul E. McKenney24278d12010-09-27 17:25:23 -0700628 default n
629 help
630 This option boosts the priority of preempted RCU readers that
631 block the current preemptible RCU grace period for too long.
632 This option also prevents heavy loads from blocking RCU
633 callback invocation for all flavors of RCU.
634
635 Say Y here if you are working with real-time apps or heavy loads
636 Say N here if you are unsure.
637
638config RCU_BOOST_PRIO
639 int "Real-time priority to boost RCU readers to"
640 range 1 99
641 depends on RCU_BOOST
642 default 1
643 help
Paul E. McKenneyc9336642012-04-18 16:20:18 -0700644 This option specifies the real-time priority to which long-term
645 preempted RCU readers are to be boosted. If you are working
646 with a real-time application that has one or more CPU-bound
647 threads running at a real-time priority level, you should set
648 RCU_BOOST_PRIO to a priority higher then the highest-priority
649 real-time CPU-bound thread. The default RCU_BOOST_PRIO value
650 of 1 is appropriate in the common case, which is real-time
651 applications that do not have any CPU-bound threads.
652
653 Some real-time applications might not have a single real-time
654 thread that saturates a given CPU, but instead might have
655 multiple real-time threads that, taken together, fully utilize
656 that CPU. In this case, you should set RCU_BOOST_PRIO to
657 a priority higher than the lowest-priority thread that is
658 conspiring to prevent the CPU from running any non-real-time
659 tasks. For example, if one thread at priority 10 and another
660 thread at priority 5 are between themselves fully consuming
661 the CPU time on a given CPU, then RCU_BOOST_PRIO should be
662 set to priority 6 or higher.
Paul E. McKenney24278d12010-09-27 17:25:23 -0700663
664 Specify the real-time priority, or take the default if unsure.
665
666config RCU_BOOST_DELAY
667 int "Milliseconds to delay boosting after RCU grace-period start"
668 range 0 3000
669 depends on RCU_BOOST
670 default 500
671 help
672 This option specifies the time to wait after the beginning of
673 a given grace period before priority-boosting preempted RCU
674 readers blocking that grace period. Note that any RCU reader
675 blocking an expedited RCU grace period is boosted immediately.
676
677 Accept the default if unsure.
678
Paul E. McKenney3fbfbf72012-08-19 21:35:53 -0700679config RCU_NOCB_CPU
Paul E. McKenney9a5739d2013-03-28 20:48:36 -0700680 bool "Offload RCU callback processing from boot-selected CPUs"
Paul E. McKenney3fbfbf72012-08-19 21:35:53 -0700681 depends on TREE_RCU || TREE_PREEMPT_RCU
682 default n
683 help
684 Use this option to reduce OS jitter for aggressive HPC or
685 real-time workloads. It can also be used to offload RCU
686 callback invocation to energy-efficient CPUs in battery-powered
687 asymmetric multiprocessors.
688
689 This option offloads callback invocation from the set of
690 CPUs specified at boot time by the rcu_nocbs parameter.
Paul E. McKenneya4889852012-12-03 08:16:28 -0800691 For each such CPU, a kthread ("rcuox/N") will be created to
692 invoke callbacks, where the "N" is the CPU being offloaded,
693 and where the "x" is "b" for RCU-bh, "p" for RCU-preempt, and
694 "s" for RCU-sched. Nothing prevents this kthread from running
695 on the specified CPUs, but (1) the kthreads may be preempted
696 between each callback, and (2) affinity or cgroups can be used
697 to force the kthreads to run on whatever set of CPUs is desired.
Paul E. McKenney3fbfbf72012-08-19 21:35:53 -0700698
Paul E. McKenney34ed62462013-01-07 13:37:42 -0800699 Say Y here if you want to help to debug reduced OS jitter.
Paul E. McKenney3fbfbf72012-08-19 21:35:53 -0700700 Say N here if you are unsure.
701
Paul E. McKenney911af502013-02-11 10:23:27 -0800702choice
703 prompt "Build-forced no-CBs CPUs"
704 default RCU_NOCB_CPU_NONE
705 help
Paul E. McKenney676c3dc2013-04-30 14:49:42 -0700706 This option allows no-CBs CPUs (whose RCU callbacks are invoked
707 from kthreads rather than from softirq context) to be specified
708 at build time. Additional no-CBs CPUs may be specified by
709 the rcu_nocbs= boot parameter.
Paul E. McKenney911af502013-02-11 10:23:27 -0800710
711config RCU_NOCB_CPU_NONE
712 bool "No build_forced no-CBs CPUs"
Frederic Weisbecker73c30822013-05-03 01:28:12 +0200713 depends on RCU_NOCB_CPU && !NO_HZ_FULL
Paul E. McKenney911af502013-02-11 10:23:27 -0800714 help
715 This option does not force any of the CPUs to be no-CBs CPUs.
716 Only CPUs designated by the rcu_nocbs= boot parameter will be
Paul E. McKenney676c3dc2013-04-30 14:49:42 -0700717 no-CBs CPUs, whose RCU callbacks will be invoked by per-CPU
718 kthreads whose names begin with "rcuo". All other CPUs will
719 invoke their own RCU callbacks in softirq context.
720
721 Select this option if you want to choose no-CBs CPUs at
722 boot time, for example, to allow testing of different no-CBs
723 configurations without having to rebuild the kernel each time.
Paul E. McKenney911af502013-02-11 10:23:27 -0800724
725config RCU_NOCB_CPU_ZERO
726 bool "CPU 0 is a build_forced no-CBs CPU"
Frederic Weisbecker73c30822013-05-03 01:28:12 +0200727 depends on RCU_NOCB_CPU && !NO_HZ_FULL
Paul E. McKenney911af502013-02-11 10:23:27 -0800728 help
Paul E. McKenney676c3dc2013-04-30 14:49:42 -0700729 This option forces CPU 0 to be a no-CBs CPU, so that its RCU
730 callbacks are invoked by a per-CPU kthread whose name begins
731 with "rcuo". Additional CPUs may be designated as no-CBs
732 CPUs using the rcu_nocbs= boot parameter will be no-CBs CPUs.
733 All other CPUs will invoke their own RCU callbacks in softirq
734 context.
Paul E. McKenney911af502013-02-11 10:23:27 -0800735
736 Select this if CPU 0 needs to be a no-CBs CPU for real-time
Paul E. McKenney676c3dc2013-04-30 14:49:42 -0700737 or energy-efficiency reasons, but the real reason it exists
738 is to ensure that randconfig testing covers mixed systems.
Paul E. McKenney911af502013-02-11 10:23:27 -0800739
740config RCU_NOCB_CPU_ALL
741 bool "All CPUs are build_forced no-CBs CPUs"
742 depends on RCU_NOCB_CPU
743 help
744 This option forces all CPUs to be no-CBs CPUs. The rcu_nocbs=
Paul E. McKenney676c3dc2013-04-30 14:49:42 -0700745 boot parameter will be ignored. All CPUs' RCU callbacks will
746 be executed in the context of per-CPU rcuo kthreads created for
747 this purpose. Assuming that the kthreads whose names start with
748 "rcuo" are bound to "housekeeping" CPUs, this reduces OS jitter
749 on the remaining CPUs, but might decrease memory locality during
750 RCU-callback invocation, thus potentially degrading throughput.
Paul E. McKenney911af502013-02-11 10:23:27 -0800751
752 Select this if all CPUs need to be no-CBs CPUs for real-time
753 or energy-efficiency reasons.
754
755endchoice
756
Mike Travisc903ff82009-01-15 12:28:29 -0800757endmenu # "RCU Subsystem"
758
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700760 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761 ---help---
762 This option enables the complete Linux kernel ".config" file
763 contents to be saved in the kernel. It provides documentation
764 of which kernel options are used in a running kernel or in an
765 on-disk kernel. This information can be extracted from the kernel
766 image file with the script scripts/extract-ikconfig and used as
767 input to rebuild the current kernel or to build another kernel.
768 It can also be extracted from a running kernel by reading
769 /proc/config.gz if enabled (below).
770
771config IKCONFIG_PROC
772 bool "Enable access to .config through /proc/config.gz"
773 depends on IKCONFIG && PROC_FS
774 ---help---
775 This option enables access to the kernel configuration file
776 through /proc/config.gz.
777
Alistair John Strachan794543a2007-05-08 00:31:15 -0700778config LOG_BUF_SHIFT
779 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
780 range 12 21
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700781 default 17
Alistair John Strachan794543a2007-05-08 00:31:15 -0700782 help
783 Select kernel log buffer size as a power of 2.
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700784 Examples:
785 17 => 128 KB
786 16 => 64 KB
787 15 => 32 KB
788 14 => 16 KB
Alistair John Strachan794543a2007-05-08 00:31:15 -0700789 13 => 8 KB
790 12 => 4 KB
791
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800792#
793# Architectures with an unreliable sched_clock() should select this:
794#
795config HAVE_UNSTABLE_SCHED_CLOCK
796 bool
797
Stephen Boyd38ff87f2013-06-01 23:39:40 -0700798config GENERIC_SCHED_CLOCK
799 bool
800
Andrea Arcangelibe3a7282012-10-04 01:50:47 +0200801#
802# For architectures that want to enable the support for NUMA-affine scheduler
803# balancing logic:
804#
805config ARCH_SUPPORTS_NUMA_BALANCING
806 bool
807
808# For architectures that (ab)use NUMA to represent different memory regions
809# all cpu-local but of different latencies, such as SuperH.
810#
811config ARCH_WANT_NUMA_VARIABLE_LOCALITY
812 bool
813
814#
815# For architectures that are willing to define _PAGE_NUMA as _PAGE_PROTNONE
816config ARCH_WANTS_PROT_NUMA_PROT_NONE
817 bool
818
819config ARCH_USES_NUMA_PROT_NONE
820 bool
821 default y
822 depends on ARCH_WANTS_PROT_NUMA_PROT_NONE
823 depends on NUMA_BALANCING
824
Mel Gorman1a687c22012-11-22 11:16:36 +0000825config NUMA_BALANCING_DEFAULT_ENABLED
826 bool "Automatically enable NUMA aware memory/task placement"
827 default y
828 depends on NUMA_BALANCING
829 help
830 If set, autonumic NUMA balancing will be enabled if running on a NUMA
831 machine.
832
Andrea Arcangelibe3a7282012-10-04 01:50:47 +0200833config NUMA_BALANCING
834 bool "Memory placement aware NUMA scheduler"
Andrea Arcangelibe3a7282012-10-04 01:50:47 +0200835 depends on ARCH_SUPPORTS_NUMA_BALANCING
836 depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY
837 depends on SMP && NUMA && MIGRATION
838 help
839 This option adds support for automatic NUMA aware memory/task placement.
840 The mechanism is quite primitive and is based on migrating memory when
841 it is references to the node the task is running on.
842
843 This system will be inactive on UMA systems.
844
Li Zefan23964d22009-01-15 13:50:58 -0800845menuconfig CGROUPS
846 boolean "Control Group support"
Kirill A. Shutemov0dea1162010-03-10 15:22:20 -0800847 depends on EVENTFD
Paul Menageddbcc7e2007-10-18 23:39:30 -0700848 help
Li Zefan23964d22009-01-15 13:50:58 -0800849 This option adds support for grouping sets of processes together, for
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800850 use with process control subsystems such as Cpusets, CFS, memory
851 controls or device isolation.
852 See
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800853 - Documentation/scheduler/sched-design-CFS.txt (CFS)
Li Zefan45ce80f2009-01-15 13:50:59 -0800854 - Documentation/cgroups/ (features for grouping, isolation
855 and resource control)
Paul Menageddbcc7e2007-10-18 23:39:30 -0700856
857 Say N if unsure.
858
Li Zefan23964d22009-01-15 13:50:58 -0800859if CGROUPS
860
Paul Menage006cb992007-10-18 23:39:43 -0700861config CGROUP_DEBUG
862 bool "Example debug cgroup subsystem"
Paul Menage418d7d82008-04-29 01:00:05 -0700863 default n
Paul Menage006cb992007-10-18 23:39:43 -0700864 help
865 This option enables a simple cgroup subsystem that
866 exports useful debugging information about the cgroups
Li Zefan23964d22009-01-15 13:50:58 -0800867 framework.
Paul Menage006cb992007-10-18 23:39:43 -0700868
Li Zefan23964d22009-01-15 13:50:58 -0800869 Say N if unsure.
Paul Menage006cb992007-10-18 23:39:43 -0700870
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700871config CGROUP_FREEZER
Li Zefan23964d22009-01-15 13:50:58 -0800872 bool "Freezer cgroup subsystem"
Li Zefan23964d22009-01-15 13:50:58 -0800873 help
874 Provides a way to freeze and unfreeze all tasks in a
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700875 cgroup.
876
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700877config CGROUP_DEVICE
878 bool "Device controller for cgroups"
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700879 help
880 Provides a cgroup implementing whitelists for devices which
881 a process in the cgroup can mknod or open.
882
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883config CPUSETS
884 bool "Cpuset support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700885 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700886 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700887 allow dynamically partitioning a system into sets of CPUs and
888 Memory Nodes and assigning tasks to run only within those sets.
889 This is primarily useful on large SMP or NUMA systems.
890
891 Say N if unsure.
892
Li Zefan23964d22009-01-15 13:50:58 -0800893config PROC_PID_CPUSET
894 bool "Include legacy /proc/<pid>/cpuset file"
895 depends on CPUSETS
896 default y
897
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100898config CGROUP_CPUACCT
899 bool "Simple CPU accounting cgroup subsystem"
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100900 help
901 Provides a simple Resource Controller for monitoring the
Li Zefan23964d22009-01-15 13:50:58 -0800902 total CPU consumed by the tasks in a cgroup.
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100903
Pavel Emelianove552b662008-02-07 00:13:49 -0800904config RESOURCE_COUNTERS
905 bool "Resource counters"
906 help
907 This option enables controller independent resource accounting
Li Zefan23964d22009-01-15 13:50:58 -0800908 infrastructure that works with cgroups.
Pavel Emelianove552b662008-02-07 00:13:49 -0800909
Andrew Mortonc255a452012-07-31 16:43:02 -0700910config MEMCG
Balbir Singh00f0b822008-03-04 14:28:39 -0800911 bool "Memory Resource Controller for Control Groups"
Daniel Lezcano79ae9c22010-10-27 15:34:39 -0700912 depends on RESOURCE_COUNTERS
Balbir Singhcf475ad2008-04-29 01:00:16 -0700913 select MM_OWNER
Balbir Singh00f0b822008-03-04 14:28:39 -0800914 help
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700915 Provides a memory resource controller that manages both anonymous
Thadeu Lima de Souza Cascardo21acb9c2009-02-04 10:12:08 +0100916 memory and page cache. (See Documentation/cgroups/memory.txt)
Balbir Singh00f0b822008-03-04 14:28:39 -0800917
918 Note that setting this option increases fixed memory overhead
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700919 associated with each page of memory in the system. By this,
Sergey Dyaslyf60e2a92013-07-03 15:03:30 -0700920 8(16)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700921 usage tracking struct at boot. Total amount of this is printed out
922 at boot.
Balbir Singh00f0b822008-03-04 14:28:39 -0800923
924 Only enable when you're ok with these trade offs and really
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700925 sure you need the memory resource controller. Even when you enable
926 this, you can set "cgroup_disable=memory" at your boot option to
927 disable memory resource controller and you can avoid overheads.
Li Zefanc9d54092009-01-07 18:07:35 -0800928 (and lose benefits of memory resource controller)
Balbir Singh00f0b822008-03-04 14:28:39 -0800929
Balbir Singhcf475ad2008-04-29 01:00:16 -0700930 This config option also selects MM_OWNER config option, which
931 could in turn add some fork/exit overhead.
932
Andrew Mortonc255a452012-07-31 16:43:02 -0700933config MEMCG_SWAP
KAMEZAWA Hiroyuki65e0e812010-08-10 18:02:56 -0700934 bool "Memory Resource Controller Swap Extension"
Andrew Mortonc255a452012-07-31 16:43:02 -0700935 depends on MEMCG && SWAP
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800936 help
937 Add swap management feature to memory resource controller. When you
938 enable this, you can limit mem+swap usage per cgroup. In other words,
939 when you disable this, memory resource controller has no cares to
940 usage of swap...a process can exhaust all of the swap. This extension
941 is useful when you want to avoid exhaustion swap but this itself
942 adds more overheads and consumes memory for remembering information.
943 Especially if you use 32bit system or small memory system, please
944 be careful about enabling this. When memory resource controller
945 is disabled by boot option, this will be automatically disabled and
946 there will be no overhead from this. Even when you set this config=y,
WANG Cong00a66d22011-07-25 17:12:12 -0700947 if boot option "swapaccount=0" is set, swap will not be accounted.
KAMEZAWA Hiroyuki627991a2009-04-02 16:57:47 -0700948 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
949 size is 4096bytes, 512k per 1Gbytes of swap.
Andrew Mortonc255a452012-07-31 16:43:02 -0700950config MEMCG_SWAP_ENABLED
Michal Hockoa42c3902010-11-24 12:57:08 -0800951 bool "Memory Resource Controller Swap Extension enabled by default"
Andrew Mortonc255a452012-07-31 16:43:02 -0700952 depends on MEMCG_SWAP
Michal Hockoa42c3902010-11-24 12:57:08 -0800953 default y
954 help
955 Memory Resource Controller Swap Extension comes with its price in
956 a bigger memory consumption. General purpose distribution kernels
Jim Cromie43d547f2010-12-17 14:32:36 -0700957 which want to enable the feature but keep it disabled by default
Michal Hocko07555ac2013-08-22 16:35:46 -0700958 and let the user enable it by swapaccount=1 boot command line
Michal Hockoa42c3902010-11-24 12:57:08 -0800959 parameter should have this option unselected.
960 For those who want to have the feature enabled by default should
961 select this option (if, for some reason, they need to disable it
WANG Cong00a66d22011-07-25 17:12:12 -0700962 then swapaccount=0 does the trick).
Andrew Mortonc255a452012-07-31 16:43:02 -0700963config MEMCG_KMEM
Kees Cook19c92392012-10-02 11:19:29 -0700964 bool "Memory Resource Controller Kernel Memory accounting"
965 depends on MEMCG
Glauber Costa510fc4e2012-12-18 14:21:47 -0800966 depends on SLUB || SLAB
Glauber Costae5671df2011-12-11 21:47:01 +0000967 help
968 The Kernel Memory extension for Memory Resource Controller can limit
969 the amount of memory used by kernel objects in the system. Those are
970 fundamentally different from the entities handled by the standard
971 Memory Controller, which are page-based, and can be swapped. Users of
972 the kmem extension can use it to guarantee that no group of processes
973 will ever exhaust kernel resources alone.
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800974
Aneesh Kumar K.V2bc64a22012-07-31 16:42:12 -0700975config CGROUP_HUGETLB
976 bool "HugeTLB Resource Controller for Control Groups"
Kees Cook19c92392012-10-02 11:19:29 -0700977 depends on RESOURCE_COUNTERS && HUGETLB_PAGE
Aneesh Kumar K.V2bc64a22012-07-31 16:42:12 -0700978 default n
979 help
980 Provides a cgroup Resource Controller for HugeTLB pages.
981 When you enable this, you can put a per cgroup limit on HugeTLB usage.
982 The limit is enforced during page fault. Since HugeTLB doesn't
983 support page reclaim, enforcing the limit at page fault time implies
984 that, the application will get SIGBUS signal if it tries to access
985 HugeTLB pages beyond its limit. This requires the application to know
986 beforehand how much HugeTLB pages it would require for its use. The
987 control group is tracked in the third page lru pointer. This means
988 that we cannot use the controller with huge page less than 3 pages.
989
Stephane Eraniane5d13672011-02-14 11:20:01 +0200990config CGROUP_PERF
991 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
992 depends on PERF_EVENTS && CGROUPS
993 help
994 This option extends the per-cpu mode to restrict monitoring to
Li Zefan2d0f2522011-03-03 14:26:20 +0800995 threads which belong to the cgroup specified and run on the
Stephane Eraniane5d13672011-02-14 11:20:01 +0200996 designated cpu.
997
998 Say N if unsure.
999
Dhaval Giani7c941432010-01-20 13:26:18 +01001000menuconfig CGROUP_SCHED
1001 bool "Group CPU scheduler"
Dhaval Giani7c941432010-01-20 13:26:18 +01001002 default n
1003 help
1004 This feature lets CPU scheduler recognize task groups and control CPU
1005 bandwidth allocation to such task groups. It uses cgroups to group
1006 tasks.
1007
1008if CGROUP_SCHED
1009config FAIR_GROUP_SCHED
1010 bool "Group scheduling for SCHED_OTHER"
1011 depends on CGROUP_SCHED
1012 default CGROUP_SCHED
1013
Paul Turnerab84d312011-07-21 09:43:28 -07001014config CFS_BANDWIDTH
1015 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
Paul Turnerab84d312011-07-21 09:43:28 -07001016 depends on FAIR_GROUP_SCHED
1017 default n
1018 help
1019 This option allows users to define CPU bandwidth rates (limits) for
1020 tasks running within the fair group scheduler. Groups with no limit
1021 set are considered to be unconstrained and will run with no
1022 restriction.
1023 See tip/Documentation/scheduler/sched-bwc.txt for more information.
1024
Dhaval Giani7c941432010-01-20 13:26:18 +01001025config RT_GROUP_SCHED
1026 bool "Group scheduling for SCHED_RR/FIFO"
Dhaval Giani7c941432010-01-20 13:26:18 +01001027 depends on CGROUP_SCHED
1028 default n
1029 help
1030 This feature lets you explicitly allocate real CPU bandwidth
Li Zefan32bd7eb2010-03-24 13:17:19 +08001031 to task groups. If enabled, it will also make it impossible to
Dhaval Giani7c941432010-01-20 13:26:18 +01001032 schedule realtime tasks for non-root users until you allocate
1033 realtime bandwidth for them.
1034 See Documentation/scheduler/sched-rt-group.txt for more information.
1035
1036endif #CGROUP_SCHED
1037
Vivek Goyalafc24d42010-04-26 19:27:56 +02001038config BLK_CGROUP
Tejun Heo32e380a2012-03-05 13:14:54 -08001039 bool "Block IO controller"
Daniel Lezcano79ae9c22010-10-27 15:34:39 -07001040 depends on BLOCK
Vivek Goyalafc24d42010-04-26 19:27:56 +02001041 default n
1042 ---help---
1043 Generic block IO controller cgroup interface. This is the common
1044 cgroup interface which should be used by various IO controlling
1045 policies.
1046
1047 Currently, CFQ IO scheduler uses it to recognize task groups and
1048 control disk bandwidth allocation (proportional time slice allocation)
Vivek Goyale43473b2010-09-15 17:06:35 -04001049 to such task groups. It is also used by bio throttling logic in
1050 block layer to implement upper limit in IO rates on a device.
Vivek Goyalafc24d42010-04-26 19:27:56 +02001051
1052 This option only enables generic Block IO controller infrastructure.
Vivek Goyale43473b2010-09-15 17:06:35 -04001053 One needs to also enable actual IO controlling logic/policy. For
Michael Witten79e2e752011-01-16 21:43:10 +00001054 enabling proportional weight division of disk bandwidth in CFQ, set
1055 CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
Michael Wittenc5e05912011-01-17 00:08:41 +00001056 CONFIG_BLK_DEV_THROTTLING=y.
Vivek Goyalafc24d42010-04-26 19:27:56 +02001057
1058 See Documentation/cgroups/blkio-controller.txt for more information.
1059
1060config DEBUG_BLK_CGROUP
1061 bool "Enable Block IO controller debugging"
1062 depends on BLK_CGROUP
1063 default n
1064 ---help---
1065 Enable some debugging help. Currently it exports additional stat
1066 files in a cgroup which can be useful for debugging.
1067
Li Zefan23964d22009-01-15 13:50:58 -08001068endif # CGROUPS
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -08001069
Cyrill Gorcunov067bce12012-01-12 17:20:49 -08001070config CHECKPOINT_RESTORE
1071 bool "Checkpoint/restore support" if EXPERT
1072 default n
1073 help
1074 Enables additional kernel features in a sake of checkpoint/restore.
1075 In particular it adds auxiliary prctl codes to setup process text,
1076 data and heap segment sizes, and a few additional /proc filesystem
1077 entries.
1078
1079 If unsure, say N here.
1080
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001081menuconfig NAMESPACES
David Rientjes6a108a12011-01-20 14:44:16 -08001082 bool "Namespaces support" if EXPERT
1083 default !EXPERT
Pavel Emelyanovc5289a62008-02-08 04:18:19 -08001084 help
1085 Provides the way to make tasks work with different objects using
1086 the same id. For example same IPC id may refer to different objects
1087 or same user id or pid may refer to different tasks when used in
1088 different namespaces.
1089
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001090if NAMESPACES
1091
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -08001092config UTS_NS
1093 bool "UTS namespace"
Daniel Lezcano17a6d442010-10-27 15:34:37 -07001094 default y
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -08001095 help
1096 In this namespace tasks see different info provided with the
1097 uname() system call
1098
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -08001099config IPC_NS
1100 bool "IPC namespace"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001101 depends on (SYSVIPC || POSIX_MQUEUE)
Daniel Lezcano17a6d442010-10-27 15:34:37 -07001102 default y
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -08001103 help
1104 In this namespace tasks work with IPC ids which correspond to
Serge E. Hallyn614b84c2009-04-06 19:01:08 -07001105 different IPC objects in different namespaces.
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -08001106
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -08001107config USER_NS
Kees Cook19c92392012-10-02 11:19:29 -07001108 bool "User namespace"
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001109 depends on UIDGID_CONVERTED
Eric W. Biederman5673a942011-11-17 10:23:55 -08001110 select UIDGID_STRICT_TYPE_CHECKS
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001111
Eric W. Biederman5673a942011-11-17 10:23:55 -08001112 default n
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -08001113 help
1114 This allows containers, i.e. vservers, to use user namespaces
1115 to provide different user info for different servers.
Eric W. Biedermane11f0ae2013-01-25 16:48:31 -08001116
1117 When user namespaces are enabled in the kernel it is
1118 recommended that the MEMCG and MEMCG_KMEM options also be
1119 enabled and that user-space use the memory control groups to
1120 limit the amount of memory a memory unprivileged users can
1121 use.
1122
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -08001123 If unsure, say N.
1124
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -08001125config PID_NS
Daniel Lezcano9bd38c22010-10-27 15:34:37 -07001126 bool "PID Namespaces"
Daniel Lezcano17a6d442010-10-27 15:34:37 -07001127 default y
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -08001128 help
Heikki Orsila12d2b8f2008-07-06 15:48:02 +03001129 Support process id namespaces. This allows having multiple
Matt LaPlante692105b2009-01-26 11:12:25 +01001130 processes with the same pid as long as they are in different
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -08001131 pid namespaces. This is a building block of containers.
1132
Matt Helsleyd6eb6332009-01-26 12:25:55 -08001133config NET_NS
1134 bool "Network namespace"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001135 depends on NET
Daniel Lezcano17a6d442010-10-27 15:34:37 -07001136 default y
Matt Helsleyd6eb6332009-01-26 12:25:55 -08001137 help
1138 Allow user space to create what appear to be multiple instances
1139 of the network stack.
1140
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001141endif # NAMESPACES
1142
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001143config UIDGID_CONVERTED
1144 # True if all of the selected software conmponents are known
1145 # to have uid_t and gid_t converted to kuid_t and kgid_t
1146 # where appropriate and are otherwise safe to use with
1147 # the user namespace.
1148 bool
1149 default y
1150
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001151 # Filesystems
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001152 depends on XFS_FS = n
1153
Eric W. Biederman5673a942011-11-17 10:23:55 -08001154config UIDGID_STRICT_TYPE_CHECKS
1155 bool "Require conversions between uid/gids and their internal representation"
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001156 depends on UIDGID_CONVERTED
Eric W. Biederman5673a942011-11-17 10:23:55 -08001157 default n
1158 help
1159 While the nececessary conversions are being added to all subsystems this option allows
1160 the code to continue to build for unconverted subsystems.
1161
1162 Say Y here if you want the strict type checking enabled
1163
Mike Galbraith5091faa2010-11-30 14:18:03 +01001164config SCHED_AUTOGROUP
1165 bool "Automatic process group scheduling"
1166 select EVENTFD
1167 select CGROUPS
1168 select CGROUP_SCHED
1169 select FAIR_GROUP_SCHED
1170 help
1171 This option optimizes the scheduler for common desktop workloads by
1172 automatically creating and populating task groups. This separation
1173 of workloads isolates aggressive CPU burners (like build jobs) from
1174 desktop applications. Task group autogeneration is currently based
1175 upon task session.
1176
Daniel Lezcano7af37be2010-10-27 15:34:41 -07001177config MM_OWNER
1178 bool
1179
1180config SYSFS_DEPRECATED
Ferenc Wagner5d6a4ea2011-01-10 19:04:22 +01001181 bool "Enable deprecated sysfs features to support old userspace tools"
Daniel Lezcano7af37be2010-10-27 15:34:41 -07001182 depends on SYSFS
1183 default n
1184 help
1185 This option adds code that switches the layout of the "block" class
1186 devices, to not show up in /sys/class/block/, but only in
1187 /sys/block/.
1188
1189 This switch is only active when the sysfs.deprecated=1 boot option is
1190 passed or the SYSFS_DEPRECATED_V2 option is set.
1191
1192 This option allows new kernels to run on old distributions and tools,
1193 which might get confused by /sys/class/block/. Since 2007/2008 all
1194 major distributions and tools handle this just fine.
1195
1196 Recent distributions and userspace tools after 2009/2010 depend on
1197 the existence of /sys/class/block/, and will not work with this
1198 option enabled.
1199
1200 Only if you are using a new kernel on an old distribution, you might
1201 need to say Y here.
1202
1203config SYSFS_DEPRECATED_V2
Ferenc Wagner5d6a4ea2011-01-10 19:04:22 +01001204 bool "Enable deprecated sysfs features by default"
Daniel Lezcano7af37be2010-10-27 15:34:41 -07001205 default n
1206 depends on SYSFS
1207 depends on SYSFS_DEPRECATED
1208 help
1209 Enable deprecated sysfs by default.
1210
1211 See the CONFIG_SYSFS_DEPRECATED option for more details about this
1212 option.
1213
1214 Only if you are using a new kernel on an old distribution, you might
1215 need to say Y here. Even then, odds are you would not need it
1216 enabled, you can always pass the boot option if absolutely necessary.
1217
1218config RELAY
1219 bool "Kernel->user space relay support (formerly relayfs)"
1220 help
1221 This option enables support for relay interface support in
1222 certain file systems (such as debugfs).
1223 It is designed to provide an efficient mechanism for tools and
1224 facilities to relay large amounts of data from kernel space to
1225 user space.
1226
1227 If unsure, say N.
1228
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -08001229config BLK_DEV_INITRD
1230 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
1231 depends on BROKEN || !FRV
1232 help
1233 The initial RAM filesystem is a ramfs which is loaded by the
1234 boot loader (loadlin or lilo) and that is mounted as root
1235 before the normal boot procedure. It is typically used to
1236 load modules needed to mount the "real" root file system,
1237 etc. See <file:Documentation/initrd.txt> for details.
1238
1239 If RAM disk support (BLK_DEV_RAM) is also included, this
1240 also enables initial RAM disk (initrd) support and adds
1241 15 Kbytes (more on some other architectures) to the kernel size.
1242
1243 If unsure say Y.
1244
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -08001245if BLK_DEV_INITRD
1246
Sam Ravnborgdbec4862005-08-10 20:44:50 +02001247source "usr/Kconfig"
1248
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -08001249endif
1250
Linus Torvaldsc45b4f12005-12-14 18:52:21 -08001251config CC_OPTIMIZE_FOR_SIZE
Ingo Molnar96fffeb2008-04-28 01:39:43 +02001252 bool "Optimize for size"
Linus Torvaldsc45b4f12005-12-14 18:52:21 -08001253 help
1254 Enabling this option will pass "-Os" instead of "-O2" to gcc
1255 resulting in a smaller kernel.
1256
Kirill Smelkov3a55fb02012-11-02 15:41:01 +04001257 If unsure, say N.
Linus Torvaldsc45b4f12005-12-14 18:52:21 -08001258
Randy Dunlap08470622006-09-30 23:28:13 -07001259config SYSCTL
1260 bool
1261
Randy Dunlapb943c462009-03-10 12:55:46 -07001262config ANON_INODES
1263 bool
1264
Mike Frysinger657a5202013-04-30 15:28:45 -07001265config HAVE_UID16
1266 bool
1267
1268config SYSCTL_EXCEPTION_TRACE
1269 bool
1270 help
1271 Enable support for /proc/sys/debug/exception-trace.
1272
1273config SYSCTL_ARCH_UNALIGN_NO_WARN
1274 bool
1275 help
1276 Enable support for /proc/sys/kernel/ignore-unaligned-usertrap
1277 Allows arch to define/use @no_unaligned_warning to possibly warn
1278 about unaligned access emulation going on under the hood.
1279
1280config SYSCTL_ARCH_UNALIGN_ALLOW
1281 bool
1282 help
1283 Enable support for /proc/sys/kernel/unaligned-trap
1284 Allows arches to define/use @unaligned_enabled to runtime toggle
1285 the unaligned access emulation.
1286 see arch/parisc/kernel/unaligned.c for reference
1287
Mike Frysinger657a5202013-04-30 15:28:45 -07001288config HAVE_PCSPKR_PLATFORM
1289 bool
1290
David Rientjes6a108a12011-01-20 14:44:16 -08001291menuconfig EXPERT
1292 bool "Configure standard kernel features (expert users)"
Josh Triplettf505c552011-06-05 18:23:58 -07001293 # Unhide debug options, to make the on-by-default options visible
1294 select DEBUG_KERNEL
Linus Torvalds1da177e2005-04-16 15:20:36 -07001295 help
1296 This option allows certain base kernel options and settings
1297 to be disabled or tweaked. This is for specialized
1298 environments which can tolerate a "non-standard" kernel.
1299 Only use this if you really know what you are doing.
1300
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001301config UID16
David Rientjes6a108a12011-01-20 14:44:16 -08001302 bool "Enable 16-bit UID system calls" if EXPERT
Catalin Marinasaf1839e2012-10-08 16:28:08 -07001303 depends on HAVE_UID16
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001304 default y
1305 help
1306 This enables the legacy 16-bit UID syscall wrappers.
1307
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001308config SYSCTL_SYSCALL
David Rientjes6a108a12011-01-20 14:44:16 -08001309 bool "Sysctl syscall support" if EXPERT
Eric W. Biederman26a70342009-11-05 05:26:41 -08001310 depends on PROC_SYSCTL
WANG Congc736de62011-11-02 13:39:25 -07001311 default n
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001312 select SYSCTL
1313 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -08001314 sys_sysctl uses binary paths that have been found challenging
1315 to properly maintain and use. The interface in /proc/sys
1316 using paths with ascii names is now the primary path to this
1317 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001318
Eric W. Biederman13bb7e32006-11-08 17:44:51 -08001319 Almost nothing using the binary sysctl interface so if you are
1320 trying to save some space it is probably safe to disable this,
1321 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001322
WANG Congc736de62011-11-02 13:39:25 -07001323 If unsure say N here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001324
Linus Torvalds1da177e2005-04-16 15:20:36 -07001325config KALLSYMS
David Rientjes6a108a12011-01-20 14:44:16 -08001326 bool "Load all symbols for debugging/ksymoops" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001327 default y
1328 help
1329 Say Y here to let the kernel print out symbolic crash information and
1330 symbolic stack backtraces. This increases the size of the kernel
1331 somewhat, as all symbols have to be loaded into the kernel image.
1332
1333config KALLSYMS_ALL
1334 bool "Include all symbols in kallsyms"
1335 depends on DEBUG_KERNEL && KALLSYMS
1336 help
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001337 Normally kallsyms only contains the symbols of functions for nicer
1338 OOPS messages and backtraces (i.e., symbols from the text and inittext
1339 sections). This is sufficient for most cases. And only in very rare
1340 cases (e.g., when a debugger is used) all symbols are required (e.g.,
1341 names of variables from the data sections, etc).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001342
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001343 This option makes sure that all symbols are loaded into the kernel
1344 image (i.e., symbols from all sections) in cost of increased kernel
1345 size (depending on the kernel configuration, it may be 300KiB or
1346 something like this).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001347
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001348 Say N unless you really need all symbols.
Matt Mackalld59745c2005-05-01 08:59:02 -07001349
1350config PRINTK
1351 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001352 bool "Enable support for printk" if EXPERT
Frederic Weisbecker74876a92012-10-12 18:00:23 +02001353 select IRQ_WORK
Matt Mackalld59745c2005-05-01 08:59:02 -07001354 help
1355 This option enables normal printk support. Removing it
1356 eliminates most of the message strings from the kernel image
1357 and makes the kernel more or less silent. As this makes it
1358 very difficult to diagnose system problems, saying N here is
1359 strongly discouraged.
1360
Matt Mackallc8538a72005-05-01 08:59:01 -07001361config BUG
David Rientjes6a108a12011-01-20 14:44:16 -08001362 bool "BUG() support" if EXPERT
Matt Mackallc8538a72005-05-01 08:59:01 -07001363 default y
1364 help
1365 Disabling this option eliminates support for BUG and WARN, reducing
1366 the size of your kernel image and potentially quietly ignoring
1367 numerous fatal conditions. You should only consider disabling this
1368 option for embedded systems with no facilities for reporting errors.
1369 Just say Y.
1370
Matt Mackall708e9a72006-01-08 01:05:25 -08001371config ELF_CORE
Alex Kelly046d6622012-10-04 17:15:23 -07001372 depends on COREDUMP
Matt Mackall708e9a72006-01-08 01:05:25 -08001373 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001374 bool "Enable ELF core dumps" if EXPERT
Matt Mackall708e9a72006-01-08 01:05:25 -08001375 help
1376 Enable support for generating core dumps. Disabling saves about 4k.
1377
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001378
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +02001379config PCSPKR_PLATFORM
David Rientjes6a108a12011-01-20 14:44:16 -08001380 bool "Enable PC-Speaker support" if EXPERT
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001381 depends on HAVE_PCSPKR_PLATFORM
Ralf Baechle15f304b2011-06-01 19:04:59 +01001382 select I8253_LOCK
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +02001383 default y
1384 help
1385 This option allows to disable the internal PC-Speaker
1386 support, saving some memory.
1387
Linus Torvalds1da177e2005-04-16 15:20:36 -07001388config BASE_FULL
1389 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001390 bool "Enable full-sized data structures for core" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001391 help
1392 Disabling this option reduces the size of miscellaneous core
1393 kernel data structures. This saves memory on small machines,
1394 but may reduce performance.
1395
1396config FUTEX
David Rientjes6a108a12011-01-20 14:44:16 -08001397 bool "Enable futex support" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001398 default y
Ingo Molnar23f78d4a2006-06-27 02:54:53 -07001399 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001400 help
1401 Disabling this option will cause the kernel to be built without
1402 support for "fast userspace mutexes". The resulting kernel may not
1403 run glibc-based applications correctly.
1404
1405config EPOLL
David Rientjes6a108a12011-01-20 14:44:16 -08001406 bool "Enable eventpoll support" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001407 default y
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001408 select ANON_INODES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001409 help
1410 Disabling this option will cause the kernel to be built without
1411 support for epoll family of system calls.
1412
Davide Libenzifba2afa2007-05-10 22:23:13 -07001413config SIGNALFD
David Rientjes6a108a12011-01-20 14:44:16 -08001414 bool "Enable signalfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001415 select ANON_INODES
Davide Libenzifba2afa2007-05-10 22:23:13 -07001416 default y
1417 help
1418 Enable the signalfd() system call that allows to receive signals
1419 on a file descriptor.
1420
1421 If unsure, say Y.
1422
Davide Libenzib215e282007-05-10 22:23:16 -07001423config TIMERFD
David Rientjes6a108a12011-01-20 14:44:16 -08001424 bool "Enable timerfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001425 select ANON_INODES
Davide Libenzib215e282007-05-10 22:23:16 -07001426 default y
1427 help
1428 Enable the timerfd() system call that allows to receive timer
1429 events on a file descriptor.
1430
1431 If unsure, say Y.
1432
Davide Libenzie1ad7462007-05-10 22:23:19 -07001433config EVENTFD
David Rientjes6a108a12011-01-20 14:44:16 -08001434 bool "Enable eventfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001435 select ANON_INODES
Davide Libenzie1ad7462007-05-10 22:23:19 -07001436 default y
1437 help
1438 Enable the eventfd() system call that allows to receive both
1439 kernel notification (ie. KAIO) or userspace notifications.
1440
1441 If unsure, say Y.
1442
Linus Torvalds1da177e2005-04-16 15:20:36 -07001443config SHMEM
David Rientjes6a108a12011-01-20 14:44:16 -08001444 bool "Use full shmem filesystem" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001445 default y
1446 depends on MMU
1447 help
1448 The shmem is an internal filesystem used to manage shared memory.
1449 It is backed by swap and manages resource limits. It is also exported
1450 to userspace as tmpfs if TMPFS is enabled. Disabling this
1451 option replaces shmem and tmpfs with the much simpler ramfs code,
1452 which may be appropriate on small systems without swap.
1453
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001454config AIO
David Rientjes6a108a12011-01-20 14:44:16 -08001455 bool "Enable AIO support" if EXPERT
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001456 default y
1457 help
1458 This option enables POSIX asynchronous I/O which may by used
Mike Frysinger657a5202013-04-30 15:28:45 -07001459 by some high performance threaded applications. Disabling
1460 this option saves about 7k.
1461
1462config PCI_QUIRKS
1463 default y
1464 bool "Enable PCI quirk workarounds" if EXPERT
1465 depends on PCI
1466 help
1467 This enables workarounds for various PCI chipset
1468 bugs/quirks. Disable this only if your target machine is
1469 unaffected by PCI quirks.
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001470
Randy Dunlap6befe5f2011-04-26 12:33:21 -07001471config EMBEDDED
1472 bool "Embedded system"
1473 select EXPERT
1474 help
1475 This option should be enabled if compiling the kernel for
1476 an embedded system so certain expert options are available
1477 for configuration.
1478
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001479config HAVE_PERF_EVENTS
Thomas Gleixner0793a612008-12-04 20:12:29 +01001480 bool
Mike Frysinger018df722009-06-12 13:17:43 -04001481 help
1482 See tools/perf/design.txt for details.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001483
Peter Zijlstra906010b2009-09-21 16:08:49 +02001484config PERF_USE_VMALLOC
1485 bool
1486 help
1487 See tools/perf/design.txt for details
1488
Ingo Molnar57c0c152009-09-21 12:20:38 +02001489menu "Kernel Performance Events And Counters"
Thomas Gleixner0793a612008-12-04 20:12:29 +01001490
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001491config PERF_EVENTS
Ingo Molnar57c0c152009-09-21 12:20:38 +02001492 bool "Kernel performance events and counters"
Robert Richter392d65a2012-04-05 18:24:44 +02001493 default y if PROFILING
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001494 depends on HAVE_PERF_EVENTS
Ingo Molnar4c59e462008-12-08 19:38:33 +01001495 select ANON_INODES
Peter Zijlstrae360adb2010-10-14 14:01:34 +08001496 select IRQ_WORK
Thomas Gleixner0793a612008-12-04 20:12:29 +01001497 help
Ingo Molnar57c0c152009-09-21 12:20:38 +02001498 Enable kernel support for various performance events provided
1499 by software and hardware.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001500
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001501 Software events are supported either built-in or via the
Ingo Molnar57c0c152009-09-21 12:20:38 +02001502 use of generic tracepoints.
1503
1504 Most modern CPUs support performance events via performance
1505 counter registers. These registers count the number of certain
Thomas Gleixner0793a612008-12-04 20:12:29 +01001506 types of hw events: such as instructions executed, cachemisses
1507 suffered, or branches mis-predicted - without slowing down the
1508 kernel or applications. These registers can also trigger interrupts
1509 when a threshold number of events have passed - and can thus be
1510 used to profile the code that runs on that CPU.
1511
Ingo Molnar57c0c152009-09-21 12:20:38 +02001512 The Linux Performance Event subsystem provides an abstraction of
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001513 these software and hardware event capabilities, available via a
Ingo Molnar57c0c152009-09-21 12:20:38 +02001514 system call and used by the "perf" utility in tools/perf/. It
Thomas Gleixner0793a612008-12-04 20:12:29 +01001515 provides per task and per CPU counters, and it provides event
1516 capabilities on top of those.
1517
1518 Say Y if unsure.
1519
Peter Zijlstra906010b2009-09-21 16:08:49 +02001520config DEBUG_PERF_USE_VMALLOC
1521 default n
1522 bool "Debug: use vmalloc to back perf mmap() buffers"
1523 depends on PERF_EVENTS && DEBUG_KERNEL
1524 select PERF_USE_VMALLOC
1525 help
1526 Use vmalloc memory to back perf mmap() buffers.
1527
1528 Mostly useful for debugging the vmalloc code on platforms
1529 that don't require it.
1530
1531 Say N if unsure.
1532
Thomas Gleixner0793a612008-12-04 20:12:29 +01001533endmenu
1534
Christoph Lameterf8891e52006-06-30 01:55:45 -07001535config VM_EVENT_COUNTERS
1536 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001537 bool "Enable VM event counters for /proc/vmstat" if EXPERT
Christoph Lameterf8891e52006-06-30 01:55:45 -07001538 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001539 VM event counters are needed for event counts to be shown.
1540 This option allows the disabling of the VM event counters
David Rientjes6a108a12011-01-20 14:44:16 -08001541 on EXPERT systems. /proc/vmstat will only show page counts
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001542 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -07001543
Christoph Lameter41ecc552007-05-09 02:32:44 -07001544config SLUB_DEBUG
1545 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001546 bool "Enable SLUB debugging support" if EXPERT
Christoph Lameterf6acb632008-04-29 16:16:06 -07001547 depends on SLUB && SYSFS
Christoph Lameter41ecc552007-05-09 02:32:44 -07001548 help
1549 SLUB has extensive debug support features. Disabling these can
1550 result in significant savings in code size. This also disables
1551 SLUB sysfs support. /sys/slab will not exist and there will be
1552 no support for cache validation etc.
1553
Randy Dunlapb943c462009-03-10 12:55:46 -07001554config COMPAT_BRK
1555 bool "Disable heap randomization"
1556 default y
1557 help
1558 Randomizing heap placement makes heap exploits harder, but it
1559 also breaks ancient binaries (including anything libc5 based).
1560 This option changes the bootup default to heap randomization
Matt LaPlante692105b2009-01-26 11:12:25 +01001561 disabled, and can be overridden at runtime by setting
Randy Dunlapb943c462009-03-10 12:55:46 -07001562 /proc/sys/kernel/randomize_va_space to 2.
1563
1564 On non-ancient distros (post-2000 ones) N is usually a safe choice.
1565
Christoph Lameter81819f02007-05-06 14:49:36 -07001566choice
1567 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -07001568 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001569 help
1570 This option allows to select a slab allocator.
1571
1572config SLAB
1573 bool "SLAB"
1574 help
1575 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -07001576 well in all environments. It organizes cache hot objects in
Simon Arlott02f56212008-11-05 22:18:19 +00001577 per cpu and per node queues.
Christoph Lameter81819f02007-05-06 14:49:36 -07001578
1579config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001580 bool "SLUB (Unqueued Allocator)"
1581 help
1582 SLUB is a slab allocator that minimizes cache line usage
1583 instead of managing queues of cached objects (SLAB approach).
1584 Per cpu caching is realized using slabs of objects instead
1585 of queues of objects. SLUB can use memory efficiently
Simon Arlott02f56212008-11-05 22:18:19 +00001586 and has enhanced diagnostics. SLUB is the default choice for
1587 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -07001588
1589config SLOB
David Rientjes6a108a12011-01-20 14:44:16 -08001590 depends on EXPERT
Christoph Lameter81819f02007-05-06 14:49:36 -07001591 bool "SLOB (Simple Allocator)"
1592 help
Matt Mackall37291452008-02-04 22:29:38 -08001593 SLOB replaces the stock allocator with a drastically simpler
1594 allocator. SLOB is generally more space efficient but
1595 does not perform as well on large systems.
Christoph Lameter81819f02007-05-06 14:49:36 -07001596
1597endchoice
1598
Joonsoo Kim345c9052013-06-19 14:05:52 +09001599config SLUB_CPU_PARTIAL
1600 default y
1601 depends on SLUB
1602 bool "SLUB per cpu partial cache"
1603 help
1604 Per cpu partial caches accellerate objects allocation and freeing
1605 that is local to a processor at the price of more indeterminism
1606 in the latency of the free. On overflow these caches will be cleared
1607 which requires the taking of locks that may cause latency spikes.
1608 Typically one would choose no for a realtime system.
1609
Jie Zhangea637632009-12-14 18:00:02 -08001610config MMAP_ALLOW_UNINITIALIZED
1611 bool "Allow mmapped anonymous memory to be uninitialized"
David Rientjes6a108a12011-01-20 14:44:16 -08001612 depends on EXPERT && !MMU
Jie Zhangea637632009-12-14 18:00:02 -08001613 default n
1614 help
1615 Normally, and according to the Linux spec, anonymous memory obtained
1616 from mmap() has it's contents cleared before it is passed to
1617 userspace. Enabling this config option allows you to request that
1618 mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus
1619 providing a huge performance boost. If this option is not enabled,
1620 then the flag will be ignored.
1621
1622 This is taken advantage of by uClibc's malloc(), and also by
1623 ELF-FDPIC binfmt's brk and stack allocator.
1624
1625 Because of the obvious security issues, this option should only be
1626 enabled on embedded devices where you control what is run in
1627 userspace. Since that isn't generally a problem on no-MMU systems,
1628 it is normally safe to say Y here.
1629
1630 See Documentation/nommu-mmap.txt for more information.
1631
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001632config PROFILING
Robert Richterb309a292010-02-26 15:01:23 +01001633 bool "Profiling support"
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001634 help
1635 Say Y here to enable the extended profiling support mechanisms used
1636 by profilers such as OProfile.
1637
Ingo Molnar5f87f112008-07-23 14:15:22 +02001638#
1639# Place an empty function call at each tracepoint site. Can be
1640# dynamically changed for a probe function.
1641#
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001642config TRACEPOINTS
Ingo Molnar5f87f112008-07-23 14:15:22 +02001643 bool
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001644
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -05001645source "arch/Kconfig"
1646
Linus Torvalds1da177e2005-04-16 15:20:36 -07001647endmenu # General setup
1648
Dmitry Baryshkovee7e5512008-06-29 14:18:46 +04001649config HAVE_GENERIC_DMA_COHERENT
1650 bool
1651 default n
1652
Linus Torvalds158a9622008-01-02 13:04:48 -08001653config SLABINFO
1654 bool
1655 depends on PROC_FS
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001656 depends on SLAB || SLUB_DEBUG
Linus Torvalds158a9622008-01-02 13:04:48 -08001657 default y
1658
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001659config RT_MUTEXES
1660 boolean
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001661
Linus Torvalds1da177e2005-04-16 15:20:36 -07001662config BASE_SMALL
1663 int
1664 default 0 if BASE_FULL
1665 default 1 if !BASE_FULL
1666
Jan Engelhardt66da5732007-07-15 23:39:29 -07001667menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001668 bool "Enable loadable module support"
1669 help
1670 Kernel modules are small pieces of compiled code which can
1671 be inserted in the running kernel, rather than being
1672 permanently built into the kernel. You use the "modprobe"
1673 tool to add (and sometimes remove) them. If you say Y here,
1674 many parts of the kernel can be built as modules (by
1675 answering M instead of Y where indicated): this is most
1676 useful for infrequently used options which are not required
1677 for booting. For more information, see the man pages for
1678 modprobe, lsmod, modinfo, insmod and rmmod.
1679
1680 If you say Y here, you will need to run "make
1681 modules_install" to put the modules under /lib/modules/
1682 where modprobe can find them (you may need to be root to do
1683 this).
1684
1685 If unsure, say Y.
1686
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001687if MODULES
1688
Linus Torvalds826e4502008-05-04 17:04:16 -07001689config MODULE_FORCE_LOAD
1690 bool "Forced module loading"
Linus Torvalds826e4502008-05-04 17:04:16 -07001691 default n
1692 help
Rusty Russell91e37a72008-05-09 16:25:28 +10001693 Allow loading of modules without version information (ie. modprobe
1694 --force). Forced module loading sets the 'F' (forced) taint flag and
1695 is usually a really bad idea.
Linus Torvalds826e4502008-05-04 17:04:16 -07001696
Linus Torvalds1da177e2005-04-16 15:20:36 -07001697config MODULE_UNLOAD
1698 bool "Module unloading"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001699 help
1700 Without this option you will not be able to unload any
1701 modules (note that some modules may not be unloadable
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001702 anyway), which makes your kernel smaller, faster
1703 and simpler. If unsure, say Y.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001704
1705config MODULE_FORCE_UNLOAD
1706 bool "Forced module unloading"
Kees Cook19c92392012-10-02 11:19:29 -07001707 depends on MODULE_UNLOAD
Linus Torvalds1da177e2005-04-16 15:20:36 -07001708 help
1709 This option allows you to force a module to unload, even if the
1710 kernel believes it is unsafe: the kernel will remove the module
1711 without waiting for anyone to stop using it (using the -f option to
1712 rmmod). This is mainly for kernel developers and desperate users.
1713 If unsure, say N.
1714
Linus Torvalds1da177e2005-04-16 15:20:36 -07001715config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +01001716 bool "Module versioning support"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001717 help
1718 Usually, you have to use modules compiled with your kernel.
1719 Saying Y here makes it sometimes possible to use modules
1720 compiled for different kernels, by adding enough information
1721 to the modules to (hopefully) spot any changes which would
1722 make them incompatible with the kernel you are running. If
1723 unsure, say N.
1724
1725config MODULE_SRCVERSION_ALL
1726 bool "Source checksum for all modules"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001727 help
1728 Modules which contain a MODULE_VERSION get an extra "srcversion"
1729 field inserted into their modinfo section, which contains a
1730 sum of the source files which made it. This helps maintainers
1731 see exactly which source was used to build a module (since
1732 others sometimes change the module source without updating
1733 the version). With this option, such a "srcversion" field
1734 will be created for all modules. If unsure, say N.
1735
Rusty Russell106a4ee2012-09-26 10:09:40 +01001736config MODULE_SIG
1737 bool "Module signature verification"
1738 depends on MODULES
David Howells48ba2462012-09-26 10:11:03 +01001739 select KEYS
1740 select CRYPTO
1741 select ASYMMETRIC_KEY_TYPE
1742 select ASYMMETRIC_PUBLIC_KEY_SUBTYPE
1743 select PUBLIC_KEY_ALGO_RSA
1744 select ASN1
1745 select OID_REGISTRY
1746 select X509_CERTIFICATE_PARSER
Rusty Russell106a4ee2012-09-26 10:09:40 +01001747 help
1748 Check modules for valid signatures upon load: the signature
1749 is simply appended to the module. For more information see
1750 Documentation/module-signing.txt.
1751
David Howellsea0b6dc2012-09-26 10:09:50 +01001752 !!!WARNING!!! If you enable this option, you MUST make sure that the
1753 module DOES NOT get stripped after being signed. This includes the
1754 debuginfo strip done by some packagers (such as rpmbuild) and
1755 inclusion into an initramfs that wants the module size reduced.
1756
Rusty Russell106a4ee2012-09-26 10:09:40 +01001757config MODULE_SIG_FORCE
1758 bool "Require modules to be validly signed"
1759 depends on MODULE_SIG
1760 help
1761 Reject unsigned modules or signed modules for which we don't have a
1762 key. Without this, such modules will simply taint the kernel.
David Howellsea0b6dc2012-09-26 10:09:50 +01001763
Michal Marekd9d8d7e2013-01-25 13:41:31 +10301764config MODULE_SIG_ALL
1765 bool "Automatically sign all modules"
1766 default y
1767 depends on MODULE_SIG
1768 help
1769 Sign all modules during make modules_install. Without this option,
1770 modules must be signed manually, using the scripts/sign-file tool.
1771
1772comment "Do not forget to sign required modules with scripts/sign-file"
1773 depends on MODULE_SIG_FORCE && !MODULE_SIG_ALL
1774
David Howellsea0b6dc2012-09-26 10:09:50 +01001775choice
1776 prompt "Which hash algorithm should modules be signed with?"
1777 depends on MODULE_SIG
1778 help
1779 This determines which sort of hashing algorithm will be used during
1780 signature generation. This algorithm _must_ be built into the kernel
1781 directly so that signature verification can take place. It is not
1782 possible to load a signed module containing the algorithm to check
1783 the signature on that module.
1784
1785config MODULE_SIG_SHA1
1786 bool "Sign modules with SHA-1"
1787 select CRYPTO_SHA1
1788
1789config MODULE_SIG_SHA224
1790 bool "Sign modules with SHA-224"
1791 select CRYPTO_SHA256
1792
1793config MODULE_SIG_SHA256
1794 bool "Sign modules with SHA-256"
1795 select CRYPTO_SHA256
1796
1797config MODULE_SIG_SHA384
1798 bool "Sign modules with SHA-384"
1799 select CRYPTO_SHA512
1800
1801config MODULE_SIG_SHA512
1802 bool "Sign modules with SHA-512"
1803 select CRYPTO_SHA512
1804
1805endchoice
1806
Michal Marek22753672013-01-25 13:41:00 +10301807config MODULE_SIG_HASH
1808 string
1809 depends on MODULE_SIG
1810 default "sha1" if MODULE_SIG_SHA1
1811 default "sha224" if MODULE_SIG_SHA224
1812 default "sha256" if MODULE_SIG_SHA256
1813 default "sha384" if MODULE_SIG_SHA384
1814 default "sha512" if MODULE_SIG_SHA512
1815
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001816endif # MODULES
1817
Rusty Russell98a79d62008-12-13 21:19:41 +10301818config INIT_ALL_POSSIBLE
1819 bool
1820 help
Rusty Russell5f054e32012-03-29 15:38:31 +10301821 Back when each arch used to define their own cpu_online_mask and
1822 cpu_possible_mask, some of them chose to initialize cpu_possible_mask
Rusty Russell98a79d62008-12-13 21:19:41 +10301823 with all 1s, and others with all 0s. When they were centralised,
1824 it was better to provide this option than to break all the archs
Matt LaPlante692105b2009-01-26 11:12:25 +01001825 and have several arch maintainers pursuing me down dark alleys.
Rusty Russell98a79d62008-12-13 21:19:41 +10301826
Linus Torvalds1da177e2005-04-16 15:20:36 -07001827config STOP_MACHINE
1828 bool
1829 default y
1830 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
1831 help
1832 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001833
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001834source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -07001835
1836config PREEMPT_NOTIFIERS
1837 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +01001838
Steffen Klassert16295be2010-01-06 19:47:10 +11001839config PADATA
1840 depends on SMP
1841 bool
1842
Andi Kleen754b7b62012-10-04 17:11:27 -07001843# Can be selected by architectures with broken toolchains
1844# that get confused by correct const<->read_only section
1845# mappings
1846config BROKEN_RODATA
1847 bool
1848
David Howells4520c6a2012-09-21 23:31:13 +01001849config ASN1
1850 tristate
1851 help
1852 Build a simple ASN.1 grammar compiler that produces a bytecode output
1853 that can be interpreted by the ASN.1 stream decoder and used to
1854 inform it as to what tags are to be expected in a stream and what
1855 functions to call on what tags.
1856
Thomas Gleixner6beb0002009-11-09 15:21:34 +00001857source "kernel/Kconfig.locks"