blob: a3a2304fa6d2f1f7ea7108a73cbd179597c18aa0 [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
31config EXPERIMENTAL
Kees Cook5a958db2012-10-02 11:36:31 -070032 bool
33 default y
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
Linus Torvalds1da177e2005-04-16 15:20:36 -070035config BROKEN
36 bool
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
38config BROKEN_ON_SMP
39 bool
40 depends on BROKEN || !SMP
41 default y
42
Linus Torvalds1da177e2005-04-16 15:20:36 -070043config INIT_ENV_ARG_LIMIT
44 int
Adrian Bunkdd673bc2006-06-30 01:55:51 -070045 default 32 if !UML
46 default 128 if UML
Linus Torvalds1da177e2005-04-16 15:20:36 -070047 help
Randy Dunlap34ad92c2005-10-30 15:01:46 -080048 Maximum of each of the number of arguments and environment
49 variables passed to init from the kernel command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
Roland McGrath84336462009-12-21 16:24:06 -080052config CROSS_COMPILE
53 string "Cross-compiler tool prefix"
54 help
55 Same as running 'make CROSS_COMPILE=prefix-' but stored for
56 default make runs in this kernel build directory. You don't
57 need to set this unless you want the configured kernel build
58 directory to select the cross-compiler automatically.
59
Linus Torvalds1da177e2005-04-16 15:20:36 -070060config LOCALVERSION
61 string "Local version - append to kernel release"
62 help
63 Append an extra string to the end of your kernel version.
64 This will show up when you type uname, for example.
65 The string you set here will be appended after the contents of
66 any files with a filename matching localversion* in your
67 object and source tree, in that order. Your total string can
68 be a maximum of 64 characters.
69
Ryan Andersonaaebf432005-07-31 04:57:49 -040070config LOCALVERSION_AUTO
71 bool "Automatically append version information to the version string"
72 default y
73 help
74 This will try to automatically determine if the current tree is a
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020075 release tree by looking for git tags that belong to the current
76 top of tree revision.
Ryan Andersonaaebf432005-07-31 04:57:49 -040077
78 A string of the format -gxxxxxxxx will be added to the localversion
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020079 if a git-based tree is found. The string generated by this will be
Ryan Andersonaaebf432005-07-31 04:57:49 -040080 appended after any matching localversion* files, and after the value
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020081 set in CONFIG_LOCALVERSION.
Ryan Andersonaaebf432005-07-31 04:57:49 -040082
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020083 (The actual string used here is the first eight characters produced
84 by running the command:
85
86 $ git rev-parse --verify HEAD
87
88 which is done within the script "scripts/setlocalversion".)
Ryan Andersonaaebf432005-07-31 04:57:49 -040089
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -080090config HAVE_KERNEL_GZIP
91 bool
92
93config HAVE_KERNEL_BZIP2
94 bool
95
96config HAVE_KERNEL_LZMA
97 bool
98
Lasse Collin3ebe1242011-01-12 17:01:23 -080099config HAVE_KERNEL_XZ
100 bool
101
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800102config HAVE_KERNEL_LZO
103 bool
104
Alain Knaff30d65db2009-01-04 22:46:17 +0100105choice
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800106 prompt "Kernel compression mode"
107 default KERNEL_GZIP
Lasse Collin3ebe1242011-01-12 17:01:23 -0800108 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 -0800109 help
Alain Knaff30d65db2009-01-04 22:46:17 +0100110 The linux kernel is a kind of self-extracting executable.
111 Several compression algorithms are available, which differ
112 in efficiency, compression and decompression speed.
113 Compression speed is only relevant when building a kernel.
114 Decompression speed is relevant at each boot.
115
116 If you have any problems with bzip2 or lzma compressed
117 kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
118 version of this functionality (bzip2 only), for 2.4, was
119 supplied by Christian Ludwig)
120
121 High compression options are mostly useful for users, who
122 are low on disk space (embedded systems), but for whom ram
123 size matters less.
124
125 If in doubt, select 'gzip'
126
127config KERNEL_GZIP
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800128 bool "Gzip"
129 depends on HAVE_KERNEL_GZIP
130 help
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800131 The old and tried gzip compression. It provides a good balance
132 between compression ratio and decompression speed.
Alain Knaff30d65db2009-01-04 22:46:17 +0100133
134config KERNEL_BZIP2
135 bool "Bzip2"
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800136 depends on HAVE_KERNEL_BZIP2
Alain Knaff30d65db2009-01-04 22:46:17 +0100137 help
138 Its compression ratio and speed is intermediate.
Randy Dunlap0a4dd352012-05-31 16:26:46 -0700139 Decompression speed is slowest among the choices. The kernel
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800140 size is about 10% smaller with bzip2, in comparison to gzip.
141 Bzip2 uses a large amount of memory. For modern kernels you
142 will need at least 8MB RAM or more for booting.
Alain Knaff30d65db2009-01-04 22:46:17 +0100143
144config KERNEL_LZMA
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800145 bool "LZMA"
146 depends on HAVE_KERNEL_LZMA
147 help
Randy Dunlap0a4dd352012-05-31 16:26:46 -0700148 This compression algorithm's ratio is best. Decompression speed
149 is between gzip and bzip2. Compression is slowest.
150 The kernel size is about 33% smaller with LZMA in comparison to gzip.
Alain Knaff30d65db2009-01-04 22:46:17 +0100151
Lasse Collin3ebe1242011-01-12 17:01:23 -0800152config KERNEL_XZ
153 bool "XZ"
154 depends on HAVE_KERNEL_XZ
155 help
156 XZ uses the LZMA2 algorithm and instruction set specific
157 BCJ filters which can improve compression ratio of executable
158 code. The size of the kernel is about 30% smaller with XZ in
159 comparison to gzip. On architectures for which there is a BCJ
160 filter (i386, x86_64, ARM, IA-64, PowerPC, and SPARC), XZ
161 will create a few percent smaller kernel than plain LZMA.
162
163 The speed is about the same as with LZMA: The decompression
164 speed of XZ is better than that of bzip2 but worse than gzip
165 and LZO. Compression is slow.
166
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800167config KERNEL_LZO
168 bool "LZO"
169 depends on HAVE_KERNEL_LZO
170 help
Randy Dunlap0a4dd352012-05-31 16:26:46 -0700171 Its compression ratio is the poorest among the choices. The kernel
Stephan Sperber681b3042010-07-14 11:23:08 +0200172 size is about 10% bigger than gzip; however its speed
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800173 (both compression and decompression) is the fastest.
174
Alain Knaff30d65db2009-01-04 22:46:17 +0100175endchoice
176
Josh Triplettbd5dc172011-06-15 15:08:28 -0700177config DEFAULT_HOSTNAME
178 string "Default hostname"
179 default "(none)"
180 help
181 This option determines the default system hostname before userspace
182 calls sethostname(2). The kernel traditionally uses "(none)" here,
183 but you may wish to use a different default here to make a minimal
184 system more usable with less configuration.
185
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186config SWAP
187 bool "Support for paging of anonymous memory (swap)"
David Howells93614012006-09-30 20:45:40 +0200188 depends on MMU && BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189 default y
190 help
191 This option allows you to choose whether you want to have support
Jesper Juhl92c35042006-01-15 02:40:08 +0100192 for so called swap devices or swap files in your kernel that are
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193 used to provide more virtual memory than the actual RAM present
194 in your computer. If unsure say Y.
195
196config SYSVIPC
197 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 ---help---
199 Inter Process Communication is a suite of library functions and
200 system calls which let processes (running programs) synchronize and
201 exchange information. It is generally considered to be a good thing,
202 and some programs won't run unless you say Y here. In particular, if
203 you want to run the DOS emulator dosemu under Linux (read the
204 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
205 you'll need to say Y here.
206
207 You can find documentation about IPC with "info ipc" and also in
208 section 6.4 of the Linux Programmer's Guide, available from
209 <http://www.tldp.org/guides.html>.
210
Eric W. Biedermana5494dc2007-02-14 00:34:06 -0800211config SYSVIPC_SYSCTL
212 bool
213 depends on SYSVIPC
214 depends on SYSCTL
215 default y
216
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217config POSIX_MQUEUE
218 bool "POSIX Message Queues"
Kees Cook19c92392012-10-02 11:19:29 -0700219 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220 ---help---
221 POSIX variant of message queues is a part of IPC. In POSIX message
222 queues every message has a priority which decides about succession
223 of receiving it by a process. If you want to compile and run
224 programs written e.g. for Solaris with use of its POSIX message
Robert P. J. Dayb0e37652007-05-09 07:25:13 +0200225 queues (functions mq_*) say Y here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226
227 POSIX message queues are visible as a filesystem called 'mqueue'
228 and can be mounted somewhere if you want to do filesystem
229 operations on message queues.
230
231 If unsure, say Y.
232
Serge E. Hallynbdc8e5f2009-04-06 19:01:11 -0700233config POSIX_MQUEUE_SYSCTL
234 bool
235 depends on POSIX_MQUEUE
236 depends on SYSCTL
237 default y
238
Aneesh Kumar K.V990d6c22011-01-29 18:43:26 +0530239config FHANDLE
240 bool "open by fhandle syscalls"
241 select EXPORTFS
242 help
243 If you say Y here, a user level program will be able to map
244 file names to handle and then later use the handle for
245 different file system operations. This is useful in implementing
246 userspace file servers, which now track files using handles instead
247 of names. The handle would remain the same even if file names
248 get renamed. Enables open_by_handle_at(2) and name_to_handle_at(2)
249 syscalls.
250
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251config AUDIT
252 bool "Auditing support"
Chris Wright804a6a492005-05-11 10:52:45 +0100253 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 help
255 Enable auditing infrastructure that can be used with another
256 kernel subsystem, such as SELinux (which requires this for
257 logging of avc messages output). Does not do system-call
258 auditing without CONFIG_AUDITSYSCALL.
259
260config AUDITSYSCALL
261 bool "Enable system-call auditing support"
Will Deacon8f827a12012-07-06 15:48:16 +0100262 depends on AUDIT && (X86 || PPC || S390 || IA64 || UML || SPARC64 || SUPERH || (ARM && AEABI && !OABI_COMPAT))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263 default y if SECURITY_SELINUX
264 help
265 Enable low-overhead system-call auditing infrastructure that
266 can be used independently or with another kernel subsystem,
Eric Paris67640b62009-12-17 20:12:06 -0500267 such as SELinux.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268
Eric Paris939a67f2009-12-17 20:12:06 -0500269config AUDIT_WATCH
270 def_bool y
271 depends on AUDITSYSCALL
272 select FSNOTIFY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273
Al Viro74c3cbe2007-07-22 08:04:18 -0400274config AUDIT_TREE
275 def_bool y
Eric Paris63c882a2009-05-21 17:02:01 -0400276 depends on AUDITSYSCALL
Eric Paris28a3a7e2009-12-17 20:12:05 -0500277 select FSNOTIFY
Al Viro74c3cbe2007-07-22 08:04:18 -0400278
Eric Paris633b4542012-01-03 14:23:08 -0500279config AUDIT_LOGINUID_IMMUTABLE
280 bool "Make audit loginuid immutable"
281 depends on AUDIT
282 help
Linus Torvaldsf429ee32012-01-17 16:06:51 -0800283 The config option toggles if a task setting its loginuid requires
Eric Paris633b4542012-01-03 14:23:08 -0500284 CAP_SYS_AUDITCONTROL or if that task should require no special permissions
285 but should instead only allow setting its loginuid if it was never
286 previously set. On systems which use systemd or a similar central
287 process to restart login services this should be set to true. On older
288 systems in which an admin would typically have to directly stop and
289 start processes this should be set to false. Setting this to true allows
290 one to drop potentially dangerous capabilites from the login tasks,
291 but may not be backwards compatible with older init systems.
292
Thomas Gleixnerd9817eb2010-09-27 12:45:59 +0000293source "kernel/irq/Kconfig"
Thomas Gleixner764e0da2012-05-21 23:16:18 +0200294source "kernel/time/Kconfig"
Thomas Gleixnerd9817eb2010-09-27 12:45:59 +0000295
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200296menu "CPU/Task time and stats accounting"
297
Frederic Weisbeckerabf917c2012-07-25 07:56:04 +0200298config VIRT_CPU_ACCOUNTING
299 bool
300
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200301choice
302 prompt "Cputime accounting"
303 default TICK_CPU_ACCOUNTING if !PPC64
Stephen Rothwell02fc8d32013-02-08 14:19:38 +1100304 default VIRT_CPU_ACCOUNTING_NATIVE if PPC64
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200305
306# Kind of a stub config for the pure tick based cputime accounting
307config TICK_CPU_ACCOUNTING
308 bool "Simple tick based cputime accounting"
309 depends on !S390
310 help
311 This is the basic tick based cputime accounting that maintains
312 statistics about user, system and idle time spent on per jiffies
313 granularity.
314
315 If unsure, say Y.
316
Frederic Weisbeckerabf917c2012-07-25 07:56:04 +0200317config VIRT_CPU_ACCOUNTING_NATIVE
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200318 bool "Deterministic task and CPU time accounting"
319 depends on HAVE_VIRT_CPU_ACCOUNTING
Frederic Weisbeckerabf917c2012-07-25 07:56:04 +0200320 select VIRT_CPU_ACCOUNTING
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200321 help
322 Select this option to enable more accurate task and CPU time
323 accounting. This is done by reading a CPU counter on each
324 kernel entry and exit and on transitions within the kernel
325 between system, softirq and hardirq state, so there is a
326 small performance impact. In the case of s390 or IBM POWER > 5,
327 this also enables accounting of stolen time on logically-partitioned
328 systems.
329
Frederic Weisbeckerabf917c2012-07-25 07:56:04 +0200330config VIRT_CPU_ACCOUNTING_GEN
331 bool "Full dynticks CPU time accounting"
332 depends on HAVE_CONTEXT_TRACKING && 64BIT
333 select VIRT_CPU_ACCOUNTING
334 select CONTEXT_TRACKING
335 help
336 Select this option to enable task and CPU time accounting on full
337 dynticks systems. This accounting is implemented by watching every
338 kernel-user boundaries using the context tracking subsystem.
339 The accounting is thus performed at the expense of some significant
340 overhead.
341
342 For now this is only useful if you are working on the full
343 dynticks subsystem development.
344
345 If unsure, say N.
346
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200347config IRQ_TIME_ACCOUNTING
348 bool "Fine granularity task level IRQ time accounting"
349 depends on HAVE_IRQ_TIME_ACCOUNTING
350 help
351 Select this option to enable fine granularity task irq time
352 accounting. This is done by reading a timestamp on each
353 transitions between softirq and hardirq state, so there can be a
354 small performance impact.
355
356 If in doubt, say N here.
357
358endchoice
359
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200360config BSD_PROCESS_ACCT
361 bool "BSD Process Accounting"
362 help
363 If you say Y here, a user level program will be able to instruct the
364 kernel (via a special system call) to write process accounting
365 information to a file: whenever a process exits, information about
366 that process will be appended to the file by the kernel. The
367 information includes things such as creation time, owning user,
368 command name, memory usage, controlling terminal etc. (the complete
369 list is in the struct acct in <file:include/linux/acct.h>). It is
370 up to the user level program to do useful things with this
371 information. This is generally a good idea, so say Y.
372
373config BSD_PROCESS_ACCT_V3
374 bool "BSD Process Accounting version 3 file format"
375 depends on BSD_PROCESS_ACCT
376 default n
377 help
378 If you say Y here, the process accounting information is written
379 in a new file format that also logs the process IDs of each
380 process and it's parent. Note that this file format is incompatible
381 with previous v0/v1/v2 file formats, so you will need updated tools
382 for processing it. A preliminary version of these tools is available
383 at <http://www.gnu.org/software/acct/>.
384
385config TASKSTATS
Kees Cook19c92392012-10-02 11:19:29 -0700386 bool "Export task/process statistics through netlink"
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200387 depends on NET
388 default n
389 help
390 Export selected statistics for tasks/processes through the
391 generic netlink interface. Unlike BSD process accounting, the
392 statistics are available during the lifetime of tasks/processes as
393 responses to commands. Like BSD accounting, they are sent to user
394 space on task exit.
395
396 Say N if unsure.
397
398config TASK_DELAY_ACCT
Kees Cook19c92392012-10-02 11:19:29 -0700399 bool "Enable per-task delay accounting"
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200400 depends on TASKSTATS
401 help
402 Collect information on time spent by a task waiting for system
403 resources like cpu, synchronous block I/O completion and swapping
404 in pages. Such statistics can help in setting a task's priorities
405 relative to other tasks for cpu, io, rss limits etc.
406
407 Say N if unsure.
408
409config TASK_XACCT
Kees Cook19c92392012-10-02 11:19:29 -0700410 bool "Enable extended accounting over taskstats"
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200411 depends on TASKSTATS
412 help
413 Collect extended task accounting data and send the data
414 to userland for processing over the taskstats interface.
415
416 Say N if unsure.
417
418config TASK_IO_ACCOUNTING
Kees Cook19c92392012-10-02 11:19:29 -0700419 bool "Enable per-task storage I/O accounting"
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200420 depends on TASK_XACCT
421 help
422 Collect information on the number of bytes of storage I/O which this
423 task has caused.
424
425 Say N if unsure.
426
427endmenu # "CPU/Task time and stats accounting"
428
Mike Travisc903ff82009-01-15 12:28:29 -0800429menu "RCU Subsystem"
430
431choice
432 prompt "RCU Implementation"
Paul E. McKenney31c9a242009-04-02 21:06:25 -0700433 default TREE_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800434
Mike Travisc903ff82009-01-15 12:28:29 -0800435config TREE_RCU
436 bool "Tree-based hierarchical RCU"
Paul E. McKenney687d7a92010-07-21 06:52:40 -0700437 depends on !PREEMPT && SMP
Mike Travisc903ff82009-01-15 12:28:29 -0800438 help
439 This option selects the RCU implementation that is
440 designed for very large SMP system with hundreds or
Paul E. McKenneyc17ef452009-06-23 17:12:47 -0700441 thousands of CPUs. It also scales down nicely to
442 smaller systems.
Mike Travisc903ff82009-01-15 12:28:29 -0800443
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700444config TREE_PREEMPT_RCU
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700445 bool "Preemptible tree-based hierarchical RCU"
Paul E. McKenney9fc52d82013-01-08 15:48:33 -0800446 depends on PREEMPT
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700447 help
448 This option selects the RCU implementation that is
449 designed for very large SMP systems with hundreds or
450 thousands of CPUs, but for which real-time response
Paul E. McKenneybbe3eae2009-09-13 09:15:08 -0700451 is also required. It also scales down nicely to
452 smaller systems.
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700453
Paul E. McKenney9fc52d82013-01-08 15:48:33 -0800454 Select this option if you are unsure.
455
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -0700456config TINY_RCU
457 bool "UP-only small-memory-footprint RCU"
Paul E. McKenney8008e122011-06-08 16:31:33 -0700458 depends on !PREEMPT && !SMP
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -0700459 help
460 This option selects the RCU implementation that is
461 designed for UP systems from which real-time response
462 is not required. This option greatly reduces the
463 memory footprint of RCU.
464
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700465config TINY_PREEMPT_RCU
466 bool "Preemptible UP-only small-memory-footprint RCU"
Paul E. McKenney8008e122011-06-08 16:31:33 -0700467 depends on PREEMPT && !SMP
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700468 help
469 This option selects the RCU implementation that is designed
470 for real-time UP systems. This option greatly reduces the
471 memory footprint of RCU.
472
Mike Travisc903ff82009-01-15 12:28:29 -0800473endchoice
474
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700475config PREEMPT_RCU
476 def_bool ( TREE_PREEMPT_RCU || TINY_PREEMPT_RCU )
477 help
478 This option enables preemptible-RCU code that is common between
479 the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations.
480
Paul E. McKenney6bfc09e2012-10-19 12:49:17 -0700481config RCU_STALL_COMMON
482 def_bool ( TREE_RCU || TREE_PREEMPT_RCU || RCU_TRACE )
483 help
484 This option enables RCU CPU stall code that is common between
485 the TINY and TREE variants of RCU. The purpose is to allow
486 the tiny variants to disable RCU CPU stall warnings, while
487 making these warnings mandatory for the tree variants.
488
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100489config CONTEXT_TRACKING
490 bool
491
Frederic Weisbecker2b1d5022012-07-11 20:26:30 +0200492config RCU_USER_QS
493 bool "Consider userspace as in RCU extended quiescent state"
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100494 depends on HAVE_CONTEXT_TRACKING && SMP
495 select CONTEXT_TRACKING
Frederic Weisbecker2b1d5022012-07-11 20:26:30 +0200496 help
497 This option sets hooks on kernel / userspace boundaries and
498 puts RCU in extended quiescent state when the CPU runs in
499 userspace. It means that when a CPU runs in userspace, it is
500 excluded from the global RCU state machine and thus doesn't
Paul Gortmakeraf71bef2012-10-24 11:07:09 -0700501 try to keep the timer tick on for RCU.
Frederic Weisbecker2b1d5022012-07-11 20:26:30 +0200502
Frederic Weisbeckerd6771242012-10-11 01:48:28 +0200503 Unless you want to hack and help the development of the full
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100504 dynticks mode, you shouldn't enable this option. It also
Paul Gortmakeraf71bef2012-10-24 11:07:09 -0700505 adds unnecessary overhead.
Frederic Weisbeckerd6771242012-10-11 01:48:28 +0200506
507 If unsure say N
508
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100509config CONTEXT_TRACKING_FORCE
510 bool "Force context tracking"
511 depends on CONTEXT_TRACKING
Frederic Weisbecker1fd2b442012-07-11 20:26:40 +0200512 help
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100513 Probe on user/kernel boundaries by default in order to
514 test the features that rely on it such as userspace RCU extended
515 quiescent states.
516 This test is there for debugging until we have a real user like the
517 full dynticks mode.
Frederic Weisbeckerd6771242012-10-11 01:48:28 +0200518
Mike Travisc903ff82009-01-15 12:28:29 -0800519config RCU_FANOUT
520 int "Tree-based hierarchical RCU fanout value"
521 range 2 64 if 64BIT
522 range 2 32 if !64BIT
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700523 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800524 default 64 if 64BIT
525 default 32 if !64BIT
526 help
527 This option controls the fanout of hierarchical implementations
528 of RCU, allowing RCU to work efficiently on machines with
Paul E. McKenney4d87ffa2010-08-04 17:31:12 -0700529 large numbers of CPUs. This value must be at least the fourth
530 root of NR_CPUS, which allows NR_CPUS to be insanely large.
531 The default value of RCU_FANOUT should be used for production
532 systems, but if you are stress-testing the RCU implementation
533 itself, small RCU_FANOUT values allow you to test large-system
534 code paths on small(er) systems.
Mike Travisc903ff82009-01-15 12:28:29 -0800535
536 Select a specific number if testing RCU itself.
537 Take the default if unsure.
538
Paul E. McKenney8932a632012-04-19 12:20:14 -0700539config RCU_FANOUT_LEAF
540 int "Tree-based hierarchical RCU leaf-level fanout value"
541 range 2 RCU_FANOUT if 64BIT
542 range 2 RCU_FANOUT if !64BIT
543 depends on TREE_RCU || TREE_PREEMPT_RCU
544 default 16
545 help
546 This option controls the leaf-level fanout of hierarchical
547 implementations of RCU, and allows trading off cache misses
548 against lock contention. Systems that synchronize their
549 scheduling-clock interrupts for energy-efficiency reasons will
550 want the default because the smaller leaf-level fanout keeps
551 lock contention levels acceptably low. Very large systems
552 (hundreds or thousands of CPUs) will instead want to set this
553 value to the maximum value possible in order to reduce the
554 number of cache misses incurred during RCU's grace-period
555 initialization. These systems tend to run CPU-bound, and thus
556 are not helped by synchronized interrupts, and thus tend to
557 skew them, which reduces lock contention enough that large
558 leaf-level fanouts work well.
559
560 Select a specific number if testing RCU itself.
561
562 Select the maximum permissible value for large systems.
563
564 Take the default if unsure.
565
Mike Travisc903ff82009-01-15 12:28:29 -0800566config RCU_FANOUT_EXACT
567 bool "Disable tree-based hierarchical RCU auto-balancing"
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700568 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800569 default n
570 help
571 This option forces use of the exact RCU_FANOUT value specified,
572 regardless of imbalances in the hierarchy. This is useful for
573 testing RCU itself, and might one day be useful on systems with
574 strong NUMA behavior.
575
576 Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
577
578 Say N if unsure.
579
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800580config RCU_FAST_NO_HZ
581 bool "Accelerate last non-dyntick-idle CPU's grace periods"
Paul E. McKenneyb807fbf2011-11-03 14:56:12 -0700582 depends on NO_HZ && SMP
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800583 default n
584 help
Paul E. McKenneyc0f4dfd2012-12-28 11:30:36 -0800585 This option permits CPUs to enter dynticks-idle state even if
586 they have RCU callbacks queued, and prevents RCU from waking
587 these CPUs up more than roughly once every four jiffies (by
588 default, you can adjust this using the rcutree.rcu_idle_gp_delay
589 parameter), thus improving energy efficiency. On the other
590 hand, this option increases the duration of RCU grace periods,
591 for example, slowing down synchronize_rcu().
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800592
Paul E. McKenneyc0f4dfd2012-12-28 11:30:36 -0800593 Say Y if energy efficiency is critically important, and you
594 don't care about increased grace-period durations.
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800595
596 Say N if you are unsure.
597
Mike Travisc903ff82009-01-15 12:28:29 -0800598config TREE_RCU_TRACE
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700599 def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
Mike Travisc903ff82009-01-15 12:28:29 -0800600 select DEBUG_FS
601 help
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700602 This option provides tracing for the TREE_RCU and
603 TREE_PREEMPT_RCU implementations, permitting Makefile to
604 trivially select kernel/rcutree_trace.c.
Mike Travisc903ff82009-01-15 12:28:29 -0800605
Paul E. McKenney24278d12010-09-27 17:25:23 -0700606config RCU_BOOST
607 bool "Enable RCU priority boosting"
Paul E. McKenney27f4d282011-02-07 12:47:15 -0800608 depends on RT_MUTEXES && PREEMPT_RCU
Paul E. McKenney24278d12010-09-27 17:25:23 -0700609 default n
610 help
611 This option boosts the priority of preempted RCU readers that
612 block the current preemptible RCU grace period for too long.
613 This option also prevents heavy loads from blocking RCU
614 callback invocation for all flavors of RCU.
615
616 Say Y here if you are working with real-time apps or heavy loads
617 Say N here if you are unsure.
618
619config RCU_BOOST_PRIO
620 int "Real-time priority to boost RCU readers to"
621 range 1 99
622 depends on RCU_BOOST
623 default 1
624 help
Paul E. McKenneyc9336642012-04-18 16:20:18 -0700625 This option specifies the real-time priority to which long-term
626 preempted RCU readers are to be boosted. If you are working
627 with a real-time application that has one or more CPU-bound
628 threads running at a real-time priority level, you should set
629 RCU_BOOST_PRIO to a priority higher then the highest-priority
630 real-time CPU-bound thread. The default RCU_BOOST_PRIO value
631 of 1 is appropriate in the common case, which is real-time
632 applications that do not have any CPU-bound threads.
633
634 Some real-time applications might not have a single real-time
635 thread that saturates a given CPU, but instead might have
636 multiple real-time threads that, taken together, fully utilize
637 that CPU. In this case, you should set RCU_BOOST_PRIO to
638 a priority higher than the lowest-priority thread that is
639 conspiring to prevent the CPU from running any non-real-time
640 tasks. For example, if one thread at priority 10 and another
641 thread at priority 5 are between themselves fully consuming
642 the CPU time on a given CPU, then RCU_BOOST_PRIO should be
643 set to priority 6 or higher.
Paul E. McKenney24278d12010-09-27 17:25:23 -0700644
645 Specify the real-time priority, or take the default if unsure.
646
647config RCU_BOOST_DELAY
648 int "Milliseconds to delay boosting after RCU grace-period start"
649 range 0 3000
650 depends on RCU_BOOST
651 default 500
652 help
653 This option specifies the time to wait after the beginning of
654 a given grace period before priority-boosting preempted RCU
655 readers blocking that grace period. Note that any RCU reader
656 blocking an expedited RCU grace period is boosted immediately.
657
658 Accept the default if unsure.
659
Paul E. McKenney3fbfbf72012-08-19 21:35:53 -0700660config RCU_NOCB_CPU
Paul E. McKenney34ed62462013-01-07 13:37:42 -0800661 bool "Offload RCU callback processing from boot-selected CPUs (EXPERIMENTAL"
Paul E. McKenney3fbfbf72012-08-19 21:35:53 -0700662 depends on TREE_RCU || TREE_PREEMPT_RCU
663 default n
664 help
665 Use this option to reduce OS jitter for aggressive HPC or
666 real-time workloads. It can also be used to offload RCU
667 callback invocation to energy-efficient CPUs in battery-powered
668 asymmetric multiprocessors.
669
670 This option offloads callback invocation from the set of
671 CPUs specified at boot time by the rcu_nocbs parameter.
Paul E. McKenneya4889852012-12-03 08:16:28 -0800672 For each such CPU, a kthread ("rcuox/N") will be created to
673 invoke callbacks, where the "N" is the CPU being offloaded,
674 and where the "x" is "b" for RCU-bh, "p" for RCU-preempt, and
675 "s" for RCU-sched. Nothing prevents this kthread from running
676 on the specified CPUs, but (1) the kthreads may be preempted
677 between each callback, and (2) affinity or cgroups can be used
678 to force the kthreads to run on whatever set of CPUs is desired.
Paul E. McKenney3fbfbf72012-08-19 21:35:53 -0700679
Paul E. McKenney34ed62462013-01-07 13:37:42 -0800680 Say Y here if you want to help to debug reduced OS jitter.
Paul E. McKenney3fbfbf72012-08-19 21:35:53 -0700681 Say N here if you are unsure.
682
Paul E. McKenney911af502013-02-11 10:23:27 -0800683choice
684 prompt "Build-forced no-CBs CPUs"
685 default RCU_NOCB_CPU_NONE
686 help
687 This option allows no-CBs CPUs to be specified at build time.
688 Additional no-CBs CPUs may be specified by the rcu_nocbs=
689 boot parameter.
690
691config RCU_NOCB_CPU_NONE
692 bool "No build_forced no-CBs CPUs"
693 depends on RCU_NOCB_CPU
694 help
695 This option does not force any of the CPUs to be no-CBs CPUs.
696 Only CPUs designated by the rcu_nocbs= boot parameter will be
697 no-CBs CPUs.
698
699config RCU_NOCB_CPU_ZERO
700 bool "CPU 0 is a build_forced no-CBs CPU"
701 depends on RCU_NOCB_CPU
702 help
703 This option forces CPU 0 to be a no-CBs CPU. Additional CPUs
704 may be designated as no-CBs CPUs using the rcu_nocbs= boot
705 parameter will be no-CBs CPUs.
706
707 Select this if CPU 0 needs to be a no-CBs CPU for real-time
708 or energy-efficiency reasons.
709
710config RCU_NOCB_CPU_ALL
711 bool "All CPUs are build_forced no-CBs CPUs"
712 depends on RCU_NOCB_CPU
713 help
714 This option forces all CPUs to be no-CBs CPUs. The rcu_nocbs=
715 boot parameter will be ignored.
716
717 Select this if all CPUs need to be no-CBs CPUs for real-time
718 or energy-efficiency reasons.
719
720endchoice
721
Mike Travisc903ff82009-01-15 12:28:29 -0800722endmenu # "RCU Subsystem"
723
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700725 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 ---help---
727 This option enables the complete Linux kernel ".config" file
728 contents to be saved in the kernel. It provides documentation
729 of which kernel options are used in a running kernel or in an
730 on-disk kernel. This information can be extracted from the kernel
731 image file with the script scripts/extract-ikconfig and used as
732 input to rebuild the current kernel or to build another kernel.
733 It can also be extracted from a running kernel by reading
734 /proc/config.gz if enabled (below).
735
736config IKCONFIG_PROC
737 bool "Enable access to .config through /proc/config.gz"
738 depends on IKCONFIG && PROC_FS
739 ---help---
740 This option enables access to the kernel configuration file
741 through /proc/config.gz.
742
Alistair John Strachan794543a2007-05-08 00:31:15 -0700743config LOG_BUF_SHIFT
744 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
745 range 12 21
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700746 default 17
Alistair John Strachan794543a2007-05-08 00:31:15 -0700747 help
748 Select kernel log buffer size as a power of 2.
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700749 Examples:
750 17 => 128 KB
751 16 => 64 KB
752 15 => 32 KB
753 14 => 16 KB
Alistair John Strachan794543a2007-05-08 00:31:15 -0700754 13 => 8 KB
755 12 => 4 KB
756
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800757#
758# Architectures with an unreliable sched_clock() should select this:
759#
760config HAVE_UNSTABLE_SCHED_CLOCK
761 bool
762
Andrea Arcangelibe3a7282012-10-04 01:50:47 +0200763#
764# For architectures that want to enable the support for NUMA-affine scheduler
765# balancing logic:
766#
767config ARCH_SUPPORTS_NUMA_BALANCING
768 bool
769
770# For architectures that (ab)use NUMA to represent different memory regions
771# all cpu-local but of different latencies, such as SuperH.
772#
773config ARCH_WANT_NUMA_VARIABLE_LOCALITY
774 bool
775
776#
777# For architectures that are willing to define _PAGE_NUMA as _PAGE_PROTNONE
778config ARCH_WANTS_PROT_NUMA_PROT_NONE
779 bool
780
781config ARCH_USES_NUMA_PROT_NONE
782 bool
783 default y
784 depends on ARCH_WANTS_PROT_NUMA_PROT_NONE
785 depends on NUMA_BALANCING
786
Mel Gorman1a687c22012-11-22 11:16:36 +0000787config NUMA_BALANCING_DEFAULT_ENABLED
788 bool "Automatically enable NUMA aware memory/task placement"
789 default y
790 depends on NUMA_BALANCING
791 help
792 If set, autonumic NUMA balancing will be enabled if running on a NUMA
793 machine.
794
Andrea Arcangelibe3a7282012-10-04 01:50:47 +0200795config NUMA_BALANCING
796 bool "Memory placement aware NUMA scheduler"
Andrea Arcangelibe3a7282012-10-04 01:50:47 +0200797 depends on ARCH_SUPPORTS_NUMA_BALANCING
798 depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY
799 depends on SMP && NUMA && MIGRATION
800 help
801 This option adds support for automatic NUMA aware memory/task placement.
802 The mechanism is quite primitive and is based on migrating memory when
803 it is references to the node the task is running on.
804
805 This system will be inactive on UMA systems.
806
Li Zefan23964d22009-01-15 13:50:58 -0800807menuconfig CGROUPS
808 boolean "Control Group support"
Kirill A. Shutemov0dea1162010-03-10 15:22:20 -0800809 depends on EVENTFD
Paul Menageddbcc7e2007-10-18 23:39:30 -0700810 help
Li Zefan23964d22009-01-15 13:50:58 -0800811 This option adds support for grouping sets of processes together, for
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800812 use with process control subsystems such as Cpusets, CFS, memory
813 controls or device isolation.
814 See
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800815 - Documentation/scheduler/sched-design-CFS.txt (CFS)
Li Zefan45ce80f2009-01-15 13:50:59 -0800816 - Documentation/cgroups/ (features for grouping, isolation
817 and resource control)
Paul Menageddbcc7e2007-10-18 23:39:30 -0700818
819 Say N if unsure.
820
Li Zefan23964d22009-01-15 13:50:58 -0800821if CGROUPS
822
Paul Menage006cb992007-10-18 23:39:43 -0700823config CGROUP_DEBUG
824 bool "Example debug cgroup subsystem"
Paul Menage418d7d82008-04-29 01:00:05 -0700825 default n
Paul Menage006cb992007-10-18 23:39:43 -0700826 help
827 This option enables a simple cgroup subsystem that
828 exports useful debugging information about the cgroups
Li Zefan23964d22009-01-15 13:50:58 -0800829 framework.
Paul Menage006cb992007-10-18 23:39:43 -0700830
Li Zefan23964d22009-01-15 13:50:58 -0800831 Say N if unsure.
Paul Menage006cb992007-10-18 23:39:43 -0700832
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700833config CGROUP_FREEZER
Li Zefan23964d22009-01-15 13:50:58 -0800834 bool "Freezer cgroup subsystem"
Li Zefan23964d22009-01-15 13:50:58 -0800835 help
836 Provides a way to freeze and unfreeze all tasks in a
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700837 cgroup.
838
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700839config CGROUP_DEVICE
840 bool "Device controller for cgroups"
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700841 help
842 Provides a cgroup implementing whitelists for devices which
843 a process in the cgroup can mknod or open.
844
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845config CPUSETS
846 bool "Cpuset support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700848 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849 allow dynamically partitioning a system into sets of CPUs and
850 Memory Nodes and assigning tasks to run only within those sets.
851 This is primarily useful on large SMP or NUMA systems.
852
853 Say N if unsure.
854
Li Zefan23964d22009-01-15 13:50:58 -0800855config PROC_PID_CPUSET
856 bool "Include legacy /proc/<pid>/cpuset file"
857 depends on CPUSETS
858 default y
859
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100860config CGROUP_CPUACCT
861 bool "Simple CPU accounting cgroup subsystem"
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100862 help
863 Provides a simple Resource Controller for monitoring the
Li Zefan23964d22009-01-15 13:50:58 -0800864 total CPU consumed by the tasks in a cgroup.
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100865
Pavel Emelianove552b662008-02-07 00:13:49 -0800866config RESOURCE_COUNTERS
867 bool "Resource counters"
868 help
869 This option enables controller independent resource accounting
Li Zefan23964d22009-01-15 13:50:58 -0800870 infrastructure that works with cgroups.
Pavel Emelianove552b662008-02-07 00:13:49 -0800871
Andrew Mortonc255a452012-07-31 16:43:02 -0700872config MEMCG
Balbir Singh00f0b822008-03-04 14:28:39 -0800873 bool "Memory Resource Controller for Control Groups"
Daniel Lezcano79ae9c22010-10-27 15:34:39 -0700874 depends on RESOURCE_COUNTERS
Balbir Singhcf475ad2008-04-29 01:00:16 -0700875 select MM_OWNER
Balbir Singh00f0b822008-03-04 14:28:39 -0800876 help
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700877 Provides a memory resource controller that manages both anonymous
Thadeu Lima de Souza Cascardo21acb9c2009-02-04 10:12:08 +0100878 memory and page cache. (See Documentation/cgroups/memory.txt)
Balbir Singh00f0b822008-03-04 14:28:39 -0800879
880 Note that setting this option increases fixed memory overhead
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700881 associated with each page of memory in the system. By this,
882 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
883 usage tracking struct at boot. Total amount of this is printed out
884 at boot.
Balbir Singh00f0b822008-03-04 14:28:39 -0800885
886 Only enable when you're ok with these trade offs and really
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700887 sure you need the memory resource controller. Even when you enable
888 this, you can set "cgroup_disable=memory" at your boot option to
889 disable memory resource controller and you can avoid overheads.
Li Zefanc9d54092009-01-07 18:07:35 -0800890 (and lose benefits of memory resource controller)
Balbir Singh00f0b822008-03-04 14:28:39 -0800891
Balbir Singhcf475ad2008-04-29 01:00:16 -0700892 This config option also selects MM_OWNER config option, which
893 could in turn add some fork/exit overhead.
894
Andrew Mortonc255a452012-07-31 16:43:02 -0700895config MEMCG_SWAP
KAMEZAWA Hiroyuki65e0e812010-08-10 18:02:56 -0700896 bool "Memory Resource Controller Swap Extension"
Andrew Mortonc255a452012-07-31 16:43:02 -0700897 depends on MEMCG && SWAP
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800898 help
899 Add swap management feature to memory resource controller. When you
900 enable this, you can limit mem+swap usage per cgroup. In other words,
901 when you disable this, memory resource controller has no cares to
902 usage of swap...a process can exhaust all of the swap. This extension
903 is useful when you want to avoid exhaustion swap but this itself
904 adds more overheads and consumes memory for remembering information.
905 Especially if you use 32bit system or small memory system, please
906 be careful about enabling this. When memory resource controller
907 is disabled by boot option, this will be automatically disabled and
908 there will be no overhead from this. Even when you set this config=y,
WANG Cong00a66d22011-07-25 17:12:12 -0700909 if boot option "swapaccount=0" is set, swap will not be accounted.
KAMEZAWA Hiroyuki627991a2009-04-02 16:57:47 -0700910 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
911 size is 4096bytes, 512k per 1Gbytes of swap.
Andrew Mortonc255a452012-07-31 16:43:02 -0700912config MEMCG_SWAP_ENABLED
Michal Hockoa42c3902010-11-24 12:57:08 -0800913 bool "Memory Resource Controller Swap Extension enabled by default"
Andrew Mortonc255a452012-07-31 16:43:02 -0700914 depends on MEMCG_SWAP
Michal Hockoa42c3902010-11-24 12:57:08 -0800915 default y
916 help
917 Memory Resource Controller Swap Extension comes with its price in
918 a bigger memory consumption. General purpose distribution kernels
Jim Cromie43d547f2010-12-17 14:32:36 -0700919 which want to enable the feature but keep it disabled by default
Michal Hockoa42c3902010-11-24 12:57:08 -0800920 and let the user enable it by swapaccount boot command line
921 parameter should have this option unselected.
922 For those who want to have the feature enabled by default should
923 select this option (if, for some reason, they need to disable it
WANG Cong00a66d22011-07-25 17:12:12 -0700924 then swapaccount=0 does the trick).
Andrew Mortonc255a452012-07-31 16:43:02 -0700925config MEMCG_KMEM
Kees Cook19c92392012-10-02 11:19:29 -0700926 bool "Memory Resource Controller Kernel Memory accounting"
927 depends on MEMCG
Glauber Costa510fc4e2012-12-18 14:21:47 -0800928 depends on SLUB || SLAB
Glauber Costae5671df2011-12-11 21:47:01 +0000929 help
930 The Kernel Memory extension for Memory Resource Controller can limit
931 the amount of memory used by kernel objects in the system. Those are
932 fundamentally different from the entities handled by the standard
933 Memory Controller, which are page-based, and can be swapped. Users of
934 the kmem extension can use it to guarantee that no group of processes
935 will ever exhaust kernel resources alone.
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800936
Aneesh Kumar K.V2bc64a22012-07-31 16:42:12 -0700937config CGROUP_HUGETLB
938 bool "HugeTLB Resource Controller for Control Groups"
Kees Cook19c92392012-10-02 11:19:29 -0700939 depends on RESOURCE_COUNTERS && HUGETLB_PAGE
Aneesh Kumar K.V2bc64a22012-07-31 16:42:12 -0700940 default n
941 help
942 Provides a cgroup Resource Controller for HugeTLB pages.
943 When you enable this, you can put a per cgroup limit on HugeTLB usage.
944 The limit is enforced during page fault. Since HugeTLB doesn't
945 support page reclaim, enforcing the limit at page fault time implies
946 that, the application will get SIGBUS signal if it tries to access
947 HugeTLB pages beyond its limit. This requires the application to know
948 beforehand how much HugeTLB pages it would require for its use. The
949 control group is tracked in the third page lru pointer. This means
950 that we cannot use the controller with huge page less than 3 pages.
951
Stephane Eraniane5d13672011-02-14 11:20:01 +0200952config CGROUP_PERF
953 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
954 depends on PERF_EVENTS && CGROUPS
955 help
956 This option extends the per-cpu mode to restrict monitoring to
Li Zefan2d0f2522011-03-03 14:26:20 +0800957 threads which belong to the cgroup specified and run on the
Stephane Eraniane5d13672011-02-14 11:20:01 +0200958 designated cpu.
959
960 Say N if unsure.
961
Dhaval Giani7c941432010-01-20 13:26:18 +0100962menuconfig CGROUP_SCHED
963 bool "Group CPU scheduler"
Dhaval Giani7c941432010-01-20 13:26:18 +0100964 default n
965 help
966 This feature lets CPU scheduler recognize task groups and control CPU
967 bandwidth allocation to such task groups. It uses cgroups to group
968 tasks.
969
970if CGROUP_SCHED
971config FAIR_GROUP_SCHED
972 bool "Group scheduling for SCHED_OTHER"
973 depends on CGROUP_SCHED
974 default CGROUP_SCHED
975
Paul Turnerab84d312011-07-21 09:43:28 -0700976config CFS_BANDWIDTH
977 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
Paul Turnerab84d312011-07-21 09:43:28 -0700978 depends on FAIR_GROUP_SCHED
979 default n
980 help
981 This option allows users to define CPU bandwidth rates (limits) for
982 tasks running within the fair group scheduler. Groups with no limit
983 set are considered to be unconstrained and will run with no
984 restriction.
985 See tip/Documentation/scheduler/sched-bwc.txt for more information.
986
Dhaval Giani7c941432010-01-20 13:26:18 +0100987config RT_GROUP_SCHED
988 bool "Group scheduling for SCHED_RR/FIFO"
Dhaval Giani7c941432010-01-20 13:26:18 +0100989 depends on CGROUP_SCHED
990 default n
991 help
992 This feature lets you explicitly allocate real CPU bandwidth
Li Zefan32bd7eb2010-03-24 13:17:19 +0800993 to task groups. If enabled, it will also make it impossible to
Dhaval Giani7c941432010-01-20 13:26:18 +0100994 schedule realtime tasks for non-root users until you allocate
995 realtime bandwidth for them.
996 See Documentation/scheduler/sched-rt-group.txt for more information.
997
998endif #CGROUP_SCHED
999
Vivek Goyalafc24d42010-04-26 19:27:56 +02001000config BLK_CGROUP
Tejun Heo32e380a2012-03-05 13:14:54 -08001001 bool "Block IO controller"
Daniel Lezcano79ae9c22010-10-27 15:34:39 -07001002 depends on BLOCK
Vivek Goyalafc24d42010-04-26 19:27:56 +02001003 default n
1004 ---help---
1005 Generic block IO controller cgroup interface. This is the common
1006 cgroup interface which should be used by various IO controlling
1007 policies.
1008
1009 Currently, CFQ IO scheduler uses it to recognize task groups and
1010 control disk bandwidth allocation (proportional time slice allocation)
Vivek Goyale43473b2010-09-15 17:06:35 -04001011 to such task groups. It is also used by bio throttling logic in
1012 block layer to implement upper limit in IO rates on a device.
Vivek Goyalafc24d42010-04-26 19:27:56 +02001013
1014 This option only enables generic Block IO controller infrastructure.
Vivek Goyale43473b2010-09-15 17:06:35 -04001015 One needs to also enable actual IO controlling logic/policy. For
Michael Witten79e2e752011-01-16 21:43:10 +00001016 enabling proportional weight division of disk bandwidth in CFQ, set
1017 CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
Michael Wittenc5e05912011-01-17 00:08:41 +00001018 CONFIG_BLK_DEV_THROTTLING=y.
Vivek Goyalafc24d42010-04-26 19:27:56 +02001019
1020 See Documentation/cgroups/blkio-controller.txt for more information.
1021
1022config DEBUG_BLK_CGROUP
1023 bool "Enable Block IO controller debugging"
1024 depends on BLK_CGROUP
1025 default n
1026 ---help---
1027 Enable some debugging help. Currently it exports additional stat
1028 files in a cgroup which can be useful for debugging.
1029
Li Zefan23964d22009-01-15 13:50:58 -08001030endif # CGROUPS
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -08001031
Cyrill Gorcunov067bce12012-01-12 17:20:49 -08001032config CHECKPOINT_RESTORE
1033 bool "Checkpoint/restore support" if EXPERT
1034 default n
1035 help
1036 Enables additional kernel features in a sake of checkpoint/restore.
1037 In particular it adds auxiliary prctl codes to setup process text,
1038 data and heap segment sizes, and a few additional /proc filesystem
1039 entries.
1040
1041 If unsure, say N here.
1042
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001043menuconfig NAMESPACES
David Rientjes6a108a12011-01-20 14:44:16 -08001044 bool "Namespaces support" if EXPERT
1045 default !EXPERT
Pavel Emelyanovc5289a62008-02-08 04:18:19 -08001046 help
1047 Provides the way to make tasks work with different objects using
1048 the same id. For example same IPC id may refer to different objects
1049 or same user id or pid may refer to different tasks when used in
1050 different namespaces.
1051
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001052if NAMESPACES
1053
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -08001054config UTS_NS
1055 bool "UTS namespace"
Daniel Lezcano17a6d442010-10-27 15:34:37 -07001056 default y
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -08001057 help
1058 In this namespace tasks see different info provided with the
1059 uname() system call
1060
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -08001061config IPC_NS
1062 bool "IPC namespace"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001063 depends on (SYSVIPC || POSIX_MQUEUE)
Daniel Lezcano17a6d442010-10-27 15:34:37 -07001064 default y
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -08001065 help
1066 In this namespace tasks work with IPC ids which correspond to
Serge E. Hallyn614b84c2009-04-06 19:01:08 -07001067 different IPC objects in different namespaces.
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -08001068
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -08001069config USER_NS
Kees Cook19c92392012-10-02 11:19:29 -07001070 bool "User namespace"
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001071 depends on UIDGID_CONVERTED
Eric W. Biederman5673a942011-11-17 10:23:55 -08001072 select UIDGID_STRICT_TYPE_CHECKS
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001073
Eric W. Biederman5673a942011-11-17 10:23:55 -08001074 default n
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -08001075 help
1076 This allows containers, i.e. vservers, to use user namespaces
1077 to provide different user info for different servers.
Eric W. Biedermane11f0ae2013-01-25 16:48:31 -08001078
1079 When user namespaces are enabled in the kernel it is
1080 recommended that the MEMCG and MEMCG_KMEM options also be
1081 enabled and that user-space use the memory control groups to
1082 limit the amount of memory a memory unprivileged users can
1083 use.
1084
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -08001085 If unsure, say N.
1086
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -08001087config PID_NS
Daniel Lezcano9bd38c22010-10-27 15:34:37 -07001088 bool "PID Namespaces"
Daniel Lezcano17a6d442010-10-27 15:34:37 -07001089 default y
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -08001090 help
Heikki Orsila12d2b8f2008-07-06 15:48:02 +03001091 Support process id namespaces. This allows having multiple
Matt LaPlante692105b2009-01-26 11:12:25 +01001092 processes with the same pid as long as they are in different
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -08001093 pid namespaces. This is a building block of containers.
1094
Matt Helsleyd6eb6332009-01-26 12:25:55 -08001095config NET_NS
1096 bool "Network namespace"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001097 depends on NET
Daniel Lezcano17a6d442010-10-27 15:34:37 -07001098 default y
Matt Helsleyd6eb6332009-01-26 12:25:55 -08001099 help
1100 Allow user space to create what appear to be multiple instances
1101 of the network stack.
1102
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001103endif # NAMESPACES
1104
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001105config UIDGID_CONVERTED
1106 # True if all of the selected software conmponents are known
1107 # to have uid_t and gid_t converted to kuid_t and kgid_t
1108 # where appropriate and are otherwise safe to use with
1109 # the user namespace.
1110 bool
1111 default y
1112
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001113 # Filesystems
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001114 depends on XFS_FS = n
1115
Eric W. Biederman5673a942011-11-17 10:23:55 -08001116config UIDGID_STRICT_TYPE_CHECKS
1117 bool "Require conversions between uid/gids and their internal representation"
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001118 depends on UIDGID_CONVERTED
Eric W. Biederman5673a942011-11-17 10:23:55 -08001119 default n
1120 help
1121 While the nececessary conversions are being added to all subsystems this option allows
1122 the code to continue to build for unconverted subsystems.
1123
1124 Say Y here if you want the strict type checking enabled
1125
Mike Galbraith5091faa2010-11-30 14:18:03 +01001126config SCHED_AUTOGROUP
1127 bool "Automatic process group scheduling"
1128 select EVENTFD
1129 select CGROUPS
1130 select CGROUP_SCHED
1131 select FAIR_GROUP_SCHED
1132 help
1133 This option optimizes the scheduler for common desktop workloads by
1134 automatically creating and populating task groups. This separation
1135 of workloads isolates aggressive CPU burners (like build jobs) from
1136 desktop applications. Task group autogeneration is currently based
1137 upon task session.
1138
Daniel Lezcano7af37be2010-10-27 15:34:41 -07001139config MM_OWNER
1140 bool
1141
1142config SYSFS_DEPRECATED
Ferenc Wagner5d6a4ea2011-01-10 19:04:22 +01001143 bool "Enable deprecated sysfs features to support old userspace tools"
Daniel Lezcano7af37be2010-10-27 15:34:41 -07001144 depends on SYSFS
1145 default n
1146 help
1147 This option adds code that switches the layout of the "block" class
1148 devices, to not show up in /sys/class/block/, but only in
1149 /sys/block/.
1150
1151 This switch is only active when the sysfs.deprecated=1 boot option is
1152 passed or the SYSFS_DEPRECATED_V2 option is set.
1153
1154 This option allows new kernels to run on old distributions and tools,
1155 which might get confused by /sys/class/block/. Since 2007/2008 all
1156 major distributions and tools handle this just fine.
1157
1158 Recent distributions and userspace tools after 2009/2010 depend on
1159 the existence of /sys/class/block/, and will not work with this
1160 option enabled.
1161
1162 Only if you are using a new kernel on an old distribution, you might
1163 need to say Y here.
1164
1165config SYSFS_DEPRECATED_V2
Ferenc Wagner5d6a4ea2011-01-10 19:04:22 +01001166 bool "Enable deprecated sysfs features by default"
Daniel Lezcano7af37be2010-10-27 15:34:41 -07001167 default n
1168 depends on SYSFS
1169 depends on SYSFS_DEPRECATED
1170 help
1171 Enable deprecated sysfs by default.
1172
1173 See the CONFIG_SYSFS_DEPRECATED option for more details about this
1174 option.
1175
1176 Only if you are using a new kernel on an old distribution, you might
1177 need to say Y here. Even then, odds are you would not need it
1178 enabled, you can always pass the boot option if absolutely necessary.
1179
1180config RELAY
1181 bool "Kernel->user space relay support (formerly relayfs)"
1182 help
1183 This option enables support for relay interface support in
1184 certain file systems (such as debugfs).
1185 It is designed to provide an efficient mechanism for tools and
1186 facilities to relay large amounts of data from kernel space to
1187 user space.
1188
1189 If unsure, say N.
1190
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -08001191config BLK_DEV_INITRD
1192 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
1193 depends on BROKEN || !FRV
1194 help
1195 The initial RAM filesystem is a ramfs which is loaded by the
1196 boot loader (loadlin or lilo) and that is mounted as root
1197 before the normal boot procedure. It is typically used to
1198 load modules needed to mount the "real" root file system,
1199 etc. See <file:Documentation/initrd.txt> for details.
1200
1201 If RAM disk support (BLK_DEV_RAM) is also included, this
1202 also enables initial RAM disk (initrd) support and adds
1203 15 Kbytes (more on some other architectures) to the kernel size.
1204
1205 If unsure say Y.
1206
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -08001207if BLK_DEV_INITRD
1208
Sam Ravnborgdbec4862005-08-10 20:44:50 +02001209source "usr/Kconfig"
1210
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -08001211endif
1212
Linus Torvaldsc45b4f12005-12-14 18:52:21 -08001213config CC_OPTIMIZE_FOR_SIZE
Ingo Molnar96fffeb2008-04-28 01:39:43 +02001214 bool "Optimize for size"
Linus Torvaldsc45b4f12005-12-14 18:52:21 -08001215 help
1216 Enabling this option will pass "-Os" instead of "-O2" to gcc
1217 resulting in a smaller kernel.
1218
Kirill Smelkov3a55fb02012-11-02 15:41:01 +04001219 If unsure, say N.
Linus Torvaldsc45b4f12005-12-14 18:52:21 -08001220
Randy Dunlap08470622006-09-30 23:28:13 -07001221config SYSCTL
1222 bool
1223
Randy Dunlapb943c462009-03-10 12:55:46 -07001224config ANON_INODES
1225 bool
1226
David Rientjes6a108a12011-01-20 14:44:16 -08001227menuconfig EXPERT
1228 bool "Configure standard kernel features (expert users)"
Josh Triplettf505c552011-06-05 18:23:58 -07001229 # Unhide debug options, to make the on-by-default options visible
1230 select DEBUG_KERNEL
Linus Torvalds1da177e2005-04-16 15:20:36 -07001231 help
1232 This option allows certain base kernel options and settings
1233 to be disabled or tweaked. This is for specialized
1234 environments which can tolerate a "non-standard" kernel.
1235 Only use this if you really know what you are doing.
1236
Catalin Marinasaf1839e2012-10-08 16:28:08 -07001237config HAVE_UID16
1238 bool
1239
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001240config UID16
David Rientjes6a108a12011-01-20 14:44:16 -08001241 bool "Enable 16-bit UID system calls" if EXPERT
Catalin Marinasaf1839e2012-10-08 16:28:08 -07001242 depends on HAVE_UID16
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001243 default y
1244 help
1245 This enables the legacy 16-bit UID syscall wrappers.
1246
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001247config SYSCTL_SYSCALL
David Rientjes6a108a12011-01-20 14:44:16 -08001248 bool "Sysctl syscall support" if EXPERT
Eric W. Biederman26a70342009-11-05 05:26:41 -08001249 depends on PROC_SYSCTL
WANG Congc736de62011-11-02 13:39:25 -07001250 default n
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001251 select SYSCTL
1252 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -08001253 sys_sysctl uses binary paths that have been found challenging
1254 to properly maintain and use. The interface in /proc/sys
1255 using paths with ascii names is now the primary path to this
1256 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001257
Eric W. Biederman13bb7e32006-11-08 17:44:51 -08001258 Almost nothing using the binary sysctl interface so if you are
1259 trying to save some space it is probably safe to disable this,
1260 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001261
WANG Congc736de62011-11-02 13:39:25 -07001262 If unsure say N here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001263
Catalin Marinas7ac57a82012-10-08 16:28:16 -07001264config SYSCTL_EXCEPTION_TRACE
1265 bool
1266 help
1267 Enable support for /proc/sys/debug/exception-trace.
1268
Vineet Guptab6fca722013-01-09 20:06:28 +05301269config SYSCTL_ARCH_UNALIGN_NO_WARN
1270 bool
1271 help
1272 Enable support for /proc/sys/kernel/ignore-unaligned-usertrap
1273 Allows arch to define/use @no_unaligned_warning to possibly warn
1274 about unaligned access emulation going on under the hood.
1275
Vineet Guptabf14e3b2013-01-18 15:12:24 +05301276config SYSCTL_ARCH_UNALIGN_ALLOW
1277 bool
1278 help
1279 Enable support for /proc/sys/kernel/unaligned-trap
1280 Allows arches to define/use @unaligned_enabled to runtime toggle
1281 the unaligned access emulation.
1282 see arch/parisc/kernel/unaligned.c for reference
1283
Linus Torvalds1da177e2005-04-16 15:20:36 -07001284config KALLSYMS
David Rientjes6a108a12011-01-20 14:44:16 -08001285 bool "Load all symbols for debugging/ksymoops" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001286 default y
1287 help
1288 Say Y here to let the kernel print out symbolic crash information and
1289 symbolic stack backtraces. This increases the size of the kernel
1290 somewhat, as all symbols have to be loaded into the kernel image.
1291
1292config KALLSYMS_ALL
1293 bool "Include all symbols in kallsyms"
1294 depends on DEBUG_KERNEL && KALLSYMS
1295 help
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001296 Normally kallsyms only contains the symbols of functions for nicer
1297 OOPS messages and backtraces (i.e., symbols from the text and inittext
1298 sections). This is sufficient for most cases. And only in very rare
1299 cases (e.g., when a debugger is used) all symbols are required (e.g.,
1300 names of variables from the data sections, etc).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001301
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001302 This option makes sure that all symbols are loaded into the kernel
1303 image (i.e., symbols from all sections) in cost of increased kernel
1304 size (depending on the kernel configuration, it may be 300KiB or
1305 something like this).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001306
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001307 Say N unless you really need all symbols.
Matt Mackalld59745c2005-05-01 08:59:02 -07001308
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -08001309config HOTPLUG
Greg Kroah-Hartman45f035a2012-09-04 17:01:08 -07001310 def_bool y
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -08001311
Matt Mackalld59745c2005-05-01 08:59:02 -07001312config PRINTK
1313 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001314 bool "Enable support for printk" if EXPERT
Frederic Weisbecker74876a92012-10-12 18:00:23 +02001315 select IRQ_WORK
Matt Mackalld59745c2005-05-01 08:59:02 -07001316 help
1317 This option enables normal printk support. Removing it
1318 eliminates most of the message strings from the kernel image
1319 and makes the kernel more or less silent. As this makes it
1320 very difficult to diagnose system problems, saying N here is
1321 strongly discouraged.
1322
Matt Mackallc8538a72005-05-01 08:59:01 -07001323config BUG
David Rientjes6a108a12011-01-20 14:44:16 -08001324 bool "BUG() support" if EXPERT
Matt Mackallc8538a72005-05-01 08:59:01 -07001325 default y
1326 help
1327 Disabling this option eliminates support for BUG and WARN, reducing
1328 the size of your kernel image and potentially quietly ignoring
1329 numerous fatal conditions. You should only consider disabling this
1330 option for embedded systems with no facilities for reporting errors.
1331 Just say Y.
1332
Matt Mackall708e9a72006-01-08 01:05:25 -08001333config ELF_CORE
Alex Kelly046d6622012-10-04 17:15:23 -07001334 depends on COREDUMP
Matt Mackall708e9a72006-01-08 01:05:25 -08001335 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001336 bool "Enable ELF core dumps" if EXPERT
Matt Mackall708e9a72006-01-08 01:05:25 -08001337 help
1338 Enable support for generating core dumps. Disabling saves about 4k.
1339
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001340
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +02001341config PCSPKR_PLATFORM
David Rientjes6a108a12011-01-20 14:44:16 -08001342 bool "Enable PC-Speaker support" if EXPERT
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001343 depends on HAVE_PCSPKR_PLATFORM
Ralf Baechle15f304b2011-06-01 19:04:59 +01001344 select I8253_LOCK
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +02001345 default y
1346 help
1347 This option allows to disable the internal PC-Speaker
1348 support, saving some memory.
1349
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001350config HAVE_PCSPKR_PLATFORM
1351 bool
1352
Linus Torvalds1da177e2005-04-16 15:20:36 -07001353config BASE_FULL
1354 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001355 bool "Enable full-sized data structures for core" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001356 help
1357 Disabling this option reduces the size of miscellaneous core
1358 kernel data structures. This saves memory on small machines,
1359 but may reduce performance.
1360
1361config FUTEX
David Rientjes6a108a12011-01-20 14:44:16 -08001362 bool "Enable futex support" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001363 default y
Ingo Molnar23f78d4a2006-06-27 02:54:53 -07001364 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001365 help
1366 Disabling this option will cause the kernel to be built without
1367 support for "fast userspace mutexes". The resulting kernel may not
1368 run glibc-based applications correctly.
1369
1370config EPOLL
David Rientjes6a108a12011-01-20 14:44:16 -08001371 bool "Enable eventpoll support" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001372 default y
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001373 select ANON_INODES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001374 help
1375 Disabling this option will cause the kernel to be built without
1376 support for epoll family of system calls.
1377
Davide Libenzifba2afa2007-05-10 22:23:13 -07001378config SIGNALFD
David Rientjes6a108a12011-01-20 14:44:16 -08001379 bool "Enable signalfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001380 select ANON_INODES
Davide Libenzifba2afa2007-05-10 22:23:13 -07001381 default y
1382 help
1383 Enable the signalfd() system call that allows to receive signals
1384 on a file descriptor.
1385
1386 If unsure, say Y.
1387
Davide Libenzib215e282007-05-10 22:23:16 -07001388config TIMERFD
David Rientjes6a108a12011-01-20 14:44:16 -08001389 bool "Enable timerfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001390 select ANON_INODES
Davide Libenzib215e282007-05-10 22:23:16 -07001391 default y
1392 help
1393 Enable the timerfd() system call that allows to receive timer
1394 events on a file descriptor.
1395
1396 If unsure, say Y.
1397
Davide Libenzie1ad7462007-05-10 22:23:19 -07001398config EVENTFD
David Rientjes6a108a12011-01-20 14:44:16 -08001399 bool "Enable eventfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001400 select ANON_INODES
Davide Libenzie1ad7462007-05-10 22:23:19 -07001401 default y
1402 help
1403 Enable the eventfd() system call that allows to receive both
1404 kernel notification (ie. KAIO) or userspace notifications.
1405
1406 If unsure, say Y.
1407
Linus Torvalds1da177e2005-04-16 15:20:36 -07001408config SHMEM
David Rientjes6a108a12011-01-20 14:44:16 -08001409 bool "Use full shmem filesystem" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001410 default y
1411 depends on MMU
1412 help
1413 The shmem is an internal filesystem used to manage shared memory.
1414 It is backed by swap and manages resource limits. It is also exported
1415 to userspace as tmpfs if TMPFS is enabled. Disabling this
1416 option replaces shmem and tmpfs with the much simpler ramfs code,
1417 which may be appropriate on small systems without swap.
1418
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001419config AIO
David Rientjes6a108a12011-01-20 14:44:16 -08001420 bool "Enable AIO support" if EXPERT
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001421 default y
1422 help
1423 This option enables POSIX asynchronous I/O which may by used
1424 by some high performance threaded applications. Disabling
1425 this option saves about 7k.
1426
Randy Dunlap6befe5f2011-04-26 12:33:21 -07001427config EMBEDDED
1428 bool "Embedded system"
1429 select EXPERT
1430 help
1431 This option should be enabled if compiling the kernel for
1432 an embedded system so certain expert options are available
1433 for configuration.
1434
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001435config HAVE_PERF_EVENTS
Thomas Gleixner0793a612008-12-04 20:12:29 +01001436 bool
Mike Frysinger018df722009-06-12 13:17:43 -04001437 help
1438 See tools/perf/design.txt for details.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001439
Peter Zijlstra906010b2009-09-21 16:08:49 +02001440config PERF_USE_VMALLOC
1441 bool
1442 help
1443 See tools/perf/design.txt for details
1444
Ingo Molnar57c0c152009-09-21 12:20:38 +02001445menu "Kernel Performance Events And Counters"
Thomas Gleixner0793a612008-12-04 20:12:29 +01001446
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001447config PERF_EVENTS
Ingo Molnar57c0c152009-09-21 12:20:38 +02001448 bool "Kernel performance events and counters"
Robert Richter392d65a2012-04-05 18:24:44 +02001449 default y if PROFILING
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001450 depends on HAVE_PERF_EVENTS
Ingo Molnar4c59e462008-12-08 19:38:33 +01001451 select ANON_INODES
Peter Zijlstrae360adb2010-10-14 14:01:34 +08001452 select IRQ_WORK
Thomas Gleixner0793a612008-12-04 20:12:29 +01001453 help
Ingo Molnar57c0c152009-09-21 12:20:38 +02001454 Enable kernel support for various performance events provided
1455 by software and hardware.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001456
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001457 Software events are supported either built-in or via the
Ingo Molnar57c0c152009-09-21 12:20:38 +02001458 use of generic tracepoints.
1459
1460 Most modern CPUs support performance events via performance
1461 counter registers. These registers count the number of certain
Thomas Gleixner0793a612008-12-04 20:12:29 +01001462 types of hw events: such as instructions executed, cachemisses
1463 suffered, or branches mis-predicted - without slowing down the
1464 kernel or applications. These registers can also trigger interrupts
1465 when a threshold number of events have passed - and can thus be
1466 used to profile the code that runs on that CPU.
1467
Ingo Molnar57c0c152009-09-21 12:20:38 +02001468 The Linux Performance Event subsystem provides an abstraction of
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001469 these software and hardware event capabilities, available via a
Ingo Molnar57c0c152009-09-21 12:20:38 +02001470 system call and used by the "perf" utility in tools/perf/. It
Thomas Gleixner0793a612008-12-04 20:12:29 +01001471 provides per task and per CPU counters, and it provides event
1472 capabilities on top of those.
1473
1474 Say Y if unsure.
1475
Peter Zijlstra906010b2009-09-21 16:08:49 +02001476config DEBUG_PERF_USE_VMALLOC
1477 default n
1478 bool "Debug: use vmalloc to back perf mmap() buffers"
1479 depends on PERF_EVENTS && DEBUG_KERNEL
1480 select PERF_USE_VMALLOC
1481 help
1482 Use vmalloc memory to back perf mmap() buffers.
1483
1484 Mostly useful for debugging the vmalloc code on platforms
1485 that don't require it.
1486
1487 Say N if unsure.
1488
Thomas Gleixner0793a612008-12-04 20:12:29 +01001489endmenu
1490
Christoph Lameterf8891e52006-06-30 01:55:45 -07001491config VM_EVENT_COUNTERS
1492 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001493 bool "Enable VM event counters for /proc/vmstat" if EXPERT
Christoph Lameterf8891e52006-06-30 01:55:45 -07001494 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001495 VM event counters are needed for event counts to be shown.
1496 This option allows the disabling of the VM event counters
David Rientjes6a108a12011-01-20 14:44:16 -08001497 on EXPERT systems. /proc/vmstat will only show page counts
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001498 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -07001499
Thomas Petazzoni3d137312008-08-19 10:28:24 +02001500config PCI_QUIRKS
1501 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001502 bool "Enable PCI quirk workarounds" if EXPERT
Geert Uytterhoeven61cfc7e2008-10-22 08:53:25 +02001503 depends on PCI
Thomas Petazzoni3d137312008-08-19 10:28:24 +02001504 help
1505 This enables workarounds for various PCI chipset
1506 bugs/quirks. Disable this only if your target machine is
1507 unaffected by PCI quirks.
1508
Christoph Lameter41ecc552007-05-09 02:32:44 -07001509config SLUB_DEBUG
1510 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001511 bool "Enable SLUB debugging support" if EXPERT
Christoph Lameterf6acb632008-04-29 16:16:06 -07001512 depends on SLUB && SYSFS
Christoph Lameter41ecc552007-05-09 02:32:44 -07001513 help
1514 SLUB has extensive debug support features. Disabling these can
1515 result in significant savings in code size. This also disables
1516 SLUB sysfs support. /sys/slab will not exist and there will be
1517 no support for cache validation etc.
1518
Randy Dunlapb943c462009-03-10 12:55:46 -07001519config COMPAT_BRK
1520 bool "Disable heap randomization"
1521 default y
1522 help
1523 Randomizing heap placement makes heap exploits harder, but it
1524 also breaks ancient binaries (including anything libc5 based).
1525 This option changes the bootup default to heap randomization
Matt LaPlante692105b2009-01-26 11:12:25 +01001526 disabled, and can be overridden at runtime by setting
Randy Dunlapb943c462009-03-10 12:55:46 -07001527 /proc/sys/kernel/randomize_va_space to 2.
1528
1529 On non-ancient distros (post-2000 ones) N is usually a safe choice.
1530
Christoph Lameter81819f02007-05-06 14:49:36 -07001531choice
1532 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -07001533 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001534 help
1535 This option allows to select a slab allocator.
1536
1537config SLAB
1538 bool "SLAB"
1539 help
1540 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -07001541 well in all environments. It organizes cache hot objects in
Simon Arlott02f56212008-11-05 22:18:19 +00001542 per cpu and per node queues.
Christoph Lameter81819f02007-05-06 14:49:36 -07001543
1544config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001545 bool "SLUB (Unqueued Allocator)"
1546 help
1547 SLUB is a slab allocator that minimizes cache line usage
1548 instead of managing queues of cached objects (SLAB approach).
1549 Per cpu caching is realized using slabs of objects instead
1550 of queues of objects. SLUB can use memory efficiently
Simon Arlott02f56212008-11-05 22:18:19 +00001551 and has enhanced diagnostics. SLUB is the default choice for
1552 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -07001553
1554config SLOB
David Rientjes6a108a12011-01-20 14:44:16 -08001555 depends on EXPERT
Christoph Lameter81819f02007-05-06 14:49:36 -07001556 bool "SLOB (Simple Allocator)"
1557 help
Matt Mackall37291452008-02-04 22:29:38 -08001558 SLOB replaces the stock allocator with a drastically simpler
1559 allocator. SLOB is generally more space efficient but
1560 does not perform as well on large systems.
Christoph Lameter81819f02007-05-06 14:49:36 -07001561
1562endchoice
1563
Jie Zhangea637632009-12-14 18:00:02 -08001564config MMAP_ALLOW_UNINITIALIZED
1565 bool "Allow mmapped anonymous memory to be uninitialized"
David Rientjes6a108a12011-01-20 14:44:16 -08001566 depends on EXPERT && !MMU
Jie Zhangea637632009-12-14 18:00:02 -08001567 default n
1568 help
1569 Normally, and according to the Linux spec, anonymous memory obtained
1570 from mmap() has it's contents cleared before it is passed to
1571 userspace. Enabling this config option allows you to request that
1572 mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus
1573 providing a huge performance boost. If this option is not enabled,
1574 then the flag will be ignored.
1575
1576 This is taken advantage of by uClibc's malloc(), and also by
1577 ELF-FDPIC binfmt's brk and stack allocator.
1578
1579 Because of the obvious security issues, this option should only be
1580 enabled on embedded devices where you control what is run in
1581 userspace. Since that isn't generally a problem on no-MMU systems,
1582 it is normally safe to say Y here.
1583
1584 See Documentation/nommu-mmap.txt for more information.
1585
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001586config PROFILING
Robert Richterb309a292010-02-26 15:01:23 +01001587 bool "Profiling support"
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001588 help
1589 Say Y here to enable the extended profiling support mechanisms used
1590 by profilers such as OProfile.
1591
Ingo Molnar5f87f112008-07-23 14:15:22 +02001592#
1593# Place an empty function call at each tracepoint site. Can be
1594# dynamically changed for a probe function.
1595#
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001596config TRACEPOINTS
Ingo Molnar5f87f112008-07-23 14:15:22 +02001597 bool
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001598
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -05001599source "arch/Kconfig"
1600
Linus Torvalds1da177e2005-04-16 15:20:36 -07001601endmenu # General setup
1602
Dmitry Baryshkovee7e5512008-06-29 14:18:46 +04001603config HAVE_GENERIC_DMA_COHERENT
1604 bool
1605 default n
1606
Linus Torvalds158a9622008-01-02 13:04:48 -08001607config SLABINFO
1608 bool
1609 depends on PROC_FS
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001610 depends on SLAB || SLUB_DEBUG
Linus Torvalds158a9622008-01-02 13:04:48 -08001611 default y
1612
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001613config RT_MUTEXES
1614 boolean
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001615
Linus Torvalds1da177e2005-04-16 15:20:36 -07001616config BASE_SMALL
1617 int
1618 default 0 if BASE_FULL
1619 default 1 if !BASE_FULL
1620
Jan Engelhardt66da5732007-07-15 23:39:29 -07001621menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001622 bool "Enable loadable module support"
1623 help
1624 Kernel modules are small pieces of compiled code which can
1625 be inserted in the running kernel, rather than being
1626 permanently built into the kernel. You use the "modprobe"
1627 tool to add (and sometimes remove) them. If you say Y here,
1628 many parts of the kernel can be built as modules (by
1629 answering M instead of Y where indicated): this is most
1630 useful for infrequently used options which are not required
1631 for booting. For more information, see the man pages for
1632 modprobe, lsmod, modinfo, insmod and rmmod.
1633
1634 If you say Y here, you will need to run "make
1635 modules_install" to put the modules under /lib/modules/
1636 where modprobe can find them (you may need to be root to do
1637 this).
1638
1639 If unsure, say Y.
1640
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001641if MODULES
1642
Linus Torvalds826e4502008-05-04 17:04:16 -07001643config MODULE_FORCE_LOAD
1644 bool "Forced module loading"
Linus Torvalds826e4502008-05-04 17:04:16 -07001645 default n
1646 help
Rusty Russell91e37a72008-05-09 16:25:28 +10001647 Allow loading of modules without version information (ie. modprobe
1648 --force). Forced module loading sets the 'F' (forced) taint flag and
1649 is usually a really bad idea.
Linus Torvalds826e4502008-05-04 17:04:16 -07001650
Linus Torvalds1da177e2005-04-16 15:20:36 -07001651config MODULE_UNLOAD
1652 bool "Module unloading"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001653 help
1654 Without this option you will not be able to unload any
1655 modules (note that some modules may not be unloadable
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001656 anyway), which makes your kernel smaller, faster
1657 and simpler. If unsure, say Y.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001658
1659config MODULE_FORCE_UNLOAD
1660 bool "Forced module unloading"
Kees Cook19c92392012-10-02 11:19:29 -07001661 depends on MODULE_UNLOAD
Linus Torvalds1da177e2005-04-16 15:20:36 -07001662 help
1663 This option allows you to force a module to unload, even if the
1664 kernel believes it is unsafe: the kernel will remove the module
1665 without waiting for anyone to stop using it (using the -f option to
1666 rmmod). This is mainly for kernel developers and desperate users.
1667 If unsure, say N.
1668
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +01001670 bool "Module versioning support"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001671 help
1672 Usually, you have to use modules compiled with your kernel.
1673 Saying Y here makes it sometimes possible to use modules
1674 compiled for different kernels, by adding enough information
1675 to the modules to (hopefully) spot any changes which would
1676 make them incompatible with the kernel you are running. If
1677 unsure, say N.
1678
1679config MODULE_SRCVERSION_ALL
1680 bool "Source checksum for all modules"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001681 help
1682 Modules which contain a MODULE_VERSION get an extra "srcversion"
1683 field inserted into their modinfo section, which contains a
1684 sum of the source files which made it. This helps maintainers
1685 see exactly which source was used to build a module (since
1686 others sometimes change the module source without updating
1687 the version). With this option, such a "srcversion" field
1688 will be created for all modules. If unsure, say N.
1689
Rusty Russell106a4ee2012-09-26 10:09:40 +01001690config MODULE_SIG
1691 bool "Module signature verification"
1692 depends on MODULES
David Howells48ba2462012-09-26 10:11:03 +01001693 select KEYS
1694 select CRYPTO
1695 select ASYMMETRIC_KEY_TYPE
1696 select ASYMMETRIC_PUBLIC_KEY_SUBTYPE
1697 select PUBLIC_KEY_ALGO_RSA
1698 select ASN1
1699 select OID_REGISTRY
1700 select X509_CERTIFICATE_PARSER
Rusty Russell106a4ee2012-09-26 10:09:40 +01001701 help
1702 Check modules for valid signatures upon load: the signature
1703 is simply appended to the module. For more information see
1704 Documentation/module-signing.txt.
1705
David Howellsea0b6dc2012-09-26 10:09:50 +01001706 !!!WARNING!!! If you enable this option, you MUST make sure that the
1707 module DOES NOT get stripped after being signed. This includes the
1708 debuginfo strip done by some packagers (such as rpmbuild) and
1709 inclusion into an initramfs that wants the module size reduced.
1710
Rusty Russell106a4ee2012-09-26 10:09:40 +01001711config MODULE_SIG_FORCE
1712 bool "Require modules to be validly signed"
1713 depends on MODULE_SIG
1714 help
1715 Reject unsigned modules or signed modules for which we don't have a
1716 key. Without this, such modules will simply taint the kernel.
David Howellsea0b6dc2012-09-26 10:09:50 +01001717
Michal Marekd9d8d7e2013-01-25 13:41:31 +10301718config MODULE_SIG_ALL
1719 bool "Automatically sign all modules"
1720 default y
1721 depends on MODULE_SIG
1722 help
1723 Sign all modules during make modules_install. Without this option,
1724 modules must be signed manually, using the scripts/sign-file tool.
1725
1726comment "Do not forget to sign required modules with scripts/sign-file"
1727 depends on MODULE_SIG_FORCE && !MODULE_SIG_ALL
1728
David Howellsea0b6dc2012-09-26 10:09:50 +01001729choice
1730 prompt "Which hash algorithm should modules be signed with?"
1731 depends on MODULE_SIG
1732 help
1733 This determines which sort of hashing algorithm will be used during
1734 signature generation. This algorithm _must_ be built into the kernel
1735 directly so that signature verification can take place. It is not
1736 possible to load a signed module containing the algorithm to check
1737 the signature on that module.
1738
1739config MODULE_SIG_SHA1
1740 bool "Sign modules with SHA-1"
1741 select CRYPTO_SHA1
1742
1743config MODULE_SIG_SHA224
1744 bool "Sign modules with SHA-224"
1745 select CRYPTO_SHA256
1746
1747config MODULE_SIG_SHA256
1748 bool "Sign modules with SHA-256"
1749 select CRYPTO_SHA256
1750
1751config MODULE_SIG_SHA384
1752 bool "Sign modules with SHA-384"
1753 select CRYPTO_SHA512
1754
1755config MODULE_SIG_SHA512
1756 bool "Sign modules with SHA-512"
1757 select CRYPTO_SHA512
1758
1759endchoice
1760
Michal Marek22753672013-01-25 13:41:00 +10301761config MODULE_SIG_HASH
1762 string
1763 depends on MODULE_SIG
1764 default "sha1" if MODULE_SIG_SHA1
1765 default "sha224" if MODULE_SIG_SHA224
1766 default "sha256" if MODULE_SIG_SHA256
1767 default "sha384" if MODULE_SIG_SHA384
1768 default "sha512" if MODULE_SIG_SHA512
1769
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001770endif # MODULES
1771
Rusty Russell98a79d62008-12-13 21:19:41 +10301772config INIT_ALL_POSSIBLE
1773 bool
1774 help
Rusty Russell5f054e32012-03-29 15:38:31 +10301775 Back when each arch used to define their own cpu_online_mask and
1776 cpu_possible_mask, some of them chose to initialize cpu_possible_mask
Rusty Russell98a79d62008-12-13 21:19:41 +10301777 with all 1s, and others with all 0s. When they were centralised,
1778 it was better to provide this option than to break all the archs
Matt LaPlante692105b2009-01-26 11:12:25 +01001779 and have several arch maintainers pursuing me down dark alleys.
Rusty Russell98a79d62008-12-13 21:19:41 +10301780
Linus Torvalds1da177e2005-04-16 15:20:36 -07001781config STOP_MACHINE
1782 bool
1783 default y
1784 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
1785 help
1786 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001787
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001788source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -07001789
1790config PREEMPT_NOTIFIERS
1791 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +01001792
Steffen Klassert16295be2010-01-06 19:47:10 +11001793config PADATA
1794 depends on SMP
1795 bool
1796
Andi Kleen754b7b62012-10-04 17:11:27 -07001797# Can be selected by architectures with broken toolchains
1798# that get confused by correct const<->read_only section
1799# mappings
1800config BROKEN_RODATA
1801 bool
1802
David Howells4520c6a2012-09-21 23:31:13 +01001803config ASN1
1804 tristate
1805 help
1806 Build a simple ASN.1 grammar compiler that produces a bytecode output
1807 that can be interpreted by the ASN.1 stream decoder and used to
1808 inform it as to what tags are to be expected in a stream and what
1809 functions to call on what tags.
1810
Thomas Gleixner6beb0002009-11-09 15:21:34 +00001811source "kernel/Kconfig.locks"