blob: 8df5116621ec78d8bc638bccf909f41d84db20ee [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
Linus Torvalds1da177e2005-04-16 15:20:36 -070056config LOCALVERSION
57 string "Local version - append to kernel release"
58 help
59 Append an extra string to the end of your kernel version.
60 This will show up when you type uname, for example.
61 The string you set here will be appended after the contents of
62 any files with a filename matching localversion* in your
63 object and source tree, in that order. Your total string can
64 be a maximum of 64 characters.
65
Ryan Andersonaaebf432005-07-31 04:57:49 -040066config LOCALVERSION_AUTO
67 bool "Automatically append version information to the version string"
68 default y
69 help
70 This will try to automatically determine if the current tree is a
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020071 release tree by looking for git tags that belong to the current
72 top of tree revision.
Ryan Andersonaaebf432005-07-31 04:57:49 -040073
74 A string of the format -gxxxxxxxx will be added to the localversion
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020075 if a git-based tree is found. The string generated by this will be
Ryan Andersonaaebf432005-07-31 04:57:49 -040076 appended after any matching localversion* files, and after the value
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020077 set in CONFIG_LOCALVERSION.
Ryan Andersonaaebf432005-07-31 04:57:49 -040078
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020079 (The actual string used here is the first eight characters produced
80 by running the command:
81
82 $ git rev-parse --verify HEAD
83
84 which is done within the script "scripts/setlocalversion".)
Ryan Andersonaaebf432005-07-31 04:57:49 -040085
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -080086config HAVE_KERNEL_GZIP
87 bool
88
89config HAVE_KERNEL_BZIP2
90 bool
91
92config HAVE_KERNEL_LZMA
93 bool
94
Lasse Collin3ebe1242011-01-12 17:01:23 -080095config HAVE_KERNEL_XZ
96 bool
97
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -080098config HAVE_KERNEL_LZO
99 bool
100
Alain Knaff30d65db2009-01-04 22:46:17 +0100101choice
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800102 prompt "Kernel compression mode"
103 default KERNEL_GZIP
Lasse Collin3ebe1242011-01-12 17:01:23 -0800104 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 -0800105 help
Alain Knaff30d65db2009-01-04 22:46:17 +0100106 The linux kernel is a kind of self-extracting executable.
107 Several compression algorithms are available, which differ
108 in efficiency, compression and decompression speed.
109 Compression speed is only relevant when building a kernel.
110 Decompression speed is relevant at each boot.
111
112 If you have any problems with bzip2 or lzma compressed
113 kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
114 version of this functionality (bzip2 only), for 2.4, was
115 supplied by Christian Ludwig)
116
117 High compression options are mostly useful for users, who
118 are low on disk space (embedded systems), but for whom ram
119 size matters less.
120
121 If in doubt, select 'gzip'
122
123config KERNEL_GZIP
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800124 bool "Gzip"
125 depends on HAVE_KERNEL_GZIP
126 help
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800127 The old and tried gzip compression. It provides a good balance
128 between compression ratio and decompression speed.
Alain Knaff30d65db2009-01-04 22:46:17 +0100129
130config KERNEL_BZIP2
131 bool "Bzip2"
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800132 depends on HAVE_KERNEL_BZIP2
Alain Knaff30d65db2009-01-04 22:46:17 +0100133 help
134 Its compression ratio and speed is intermediate.
Randy Dunlap0a4dd352012-05-31 16:26:46 -0700135 Decompression speed is slowest among the choices. The kernel
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800136 size is about 10% smaller with bzip2, in comparison to gzip.
137 Bzip2 uses a large amount of memory. For modern kernels you
138 will need at least 8MB RAM or more for booting.
Alain Knaff30d65db2009-01-04 22:46:17 +0100139
140config KERNEL_LZMA
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800141 bool "LZMA"
142 depends on HAVE_KERNEL_LZMA
143 help
Randy Dunlap0a4dd352012-05-31 16:26:46 -0700144 This compression algorithm's ratio is best. Decompression speed
145 is between gzip and bzip2. Compression is slowest.
146 The kernel size is about 33% smaller with LZMA in comparison to gzip.
Alain Knaff30d65db2009-01-04 22:46:17 +0100147
Lasse Collin3ebe1242011-01-12 17:01:23 -0800148config KERNEL_XZ
149 bool "XZ"
150 depends on HAVE_KERNEL_XZ
151 help
152 XZ uses the LZMA2 algorithm and instruction set specific
153 BCJ filters which can improve compression ratio of executable
154 code. The size of the kernel is about 30% smaller with XZ in
155 comparison to gzip. On architectures for which there is a BCJ
156 filter (i386, x86_64, ARM, IA-64, PowerPC, and SPARC), XZ
157 will create a few percent smaller kernel than plain LZMA.
158
159 The speed is about the same as with LZMA: The decompression
160 speed of XZ is better than that of bzip2 but worse than gzip
161 and LZO. Compression is slow.
162
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800163config KERNEL_LZO
164 bool "LZO"
165 depends on HAVE_KERNEL_LZO
166 help
Randy Dunlap0a4dd352012-05-31 16:26:46 -0700167 Its compression ratio is the poorest among the choices. The kernel
Stephan Sperber681b3042010-07-14 11:23:08 +0200168 size is about 10% bigger than gzip; however its speed
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800169 (both compression and decompression) is the fastest.
170
Alain Knaff30d65db2009-01-04 22:46:17 +0100171endchoice
172
Josh Triplettbd5dc172011-06-15 15:08:28 -0700173config DEFAULT_HOSTNAME
174 string "Default hostname"
175 default "(none)"
176 help
177 This option determines the default system hostname before userspace
178 calls sethostname(2). The kernel traditionally uses "(none)" here,
179 but you may wish to use a different default here to make a minimal
180 system more usable with less configuration.
181
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182config SWAP
183 bool "Support for paging of anonymous memory (swap)"
David Howells93614012006-09-30 20:45:40 +0200184 depends on MMU && BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 default y
186 help
187 This option allows you to choose whether you want to have support
Jesper Juhl92c35042006-01-15 02:40:08 +0100188 for so called swap devices or swap files in your kernel that are
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189 used to provide more virtual memory than the actual RAM present
190 in your computer. If unsure say Y.
191
192config SYSVIPC
193 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 ---help---
195 Inter Process Communication is a suite of library functions and
196 system calls which let processes (running programs) synchronize and
197 exchange information. It is generally considered to be a good thing,
198 and some programs won't run unless you say Y here. In particular, if
199 you want to run the DOS emulator dosemu under Linux (read the
200 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
201 you'll need to say Y here.
202
203 You can find documentation about IPC with "info ipc" and also in
204 section 6.4 of the Linux Programmer's Guide, available from
205 <http://www.tldp.org/guides.html>.
206
Eric W. Biedermana5494dc2007-02-14 00:34:06 -0800207config SYSVIPC_SYSCTL
208 bool
209 depends on SYSVIPC
210 depends on SYSCTL
211 default y
212
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213config POSIX_MQUEUE
214 bool "POSIX Message Queues"
Kees Cook19c92392012-10-02 11:19:29 -0700215 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 ---help---
217 POSIX variant of message queues is a part of IPC. In POSIX message
218 queues every message has a priority which decides about succession
219 of receiving it by a process. If you want to compile and run
220 programs written e.g. for Solaris with use of its POSIX message
Robert P. J. Dayb0e37652007-05-09 07:25:13 +0200221 queues (functions mq_*) say Y here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222
223 POSIX message queues are visible as a filesystem called 'mqueue'
224 and can be mounted somewhere if you want to do filesystem
225 operations on message queues.
226
227 If unsure, say Y.
228
Serge E. Hallynbdc8e5f2009-04-06 19:01:11 -0700229config POSIX_MQUEUE_SYSCTL
230 bool
231 depends on POSIX_MQUEUE
232 depends on SYSCTL
233 default y
234
Aneesh Kumar K.V990d6c22011-01-29 18:43:26 +0530235config FHANDLE
236 bool "open by fhandle syscalls"
237 select EXPORTFS
238 help
239 If you say Y here, a user level program will be able to map
240 file names to handle and then later use the handle for
241 different file system operations. This is useful in implementing
242 userspace file servers, which now track files using handles instead
243 of names. The handle would remain the same even if file names
244 get renamed. Enables open_by_handle_at(2) and name_to_handle_at(2)
245 syscalls.
246
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247config AUDIT
248 bool "Auditing support"
Chris Wright804a6a492005-05-11 10:52:45 +0100249 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 help
251 Enable auditing infrastructure that can be used with another
252 kernel subsystem, such as SELinux (which requires this for
253 logging of avc messages output). Does not do system-call
254 auditing without CONFIG_AUDITSYSCALL.
255
256config AUDITSYSCALL
257 bool "Enable system-call auditing support"
Will Deacon8f827a12012-07-06 15:48:16 +0100258 depends on AUDIT && (X86 || PPC || S390 || IA64 || UML || SPARC64 || SUPERH || (ARM && AEABI && !OABI_COMPAT))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259 default y if SECURITY_SELINUX
260 help
261 Enable low-overhead system-call auditing infrastructure that
262 can be used independently or with another kernel subsystem,
Eric Paris67640b62009-12-17 20:12:06 -0500263 such as SELinux.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264
Eric Paris939a67f2009-12-17 20:12:06 -0500265config AUDIT_WATCH
266 def_bool y
267 depends on AUDITSYSCALL
268 select FSNOTIFY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269
Al Viro74c3cbe2007-07-22 08:04:18 -0400270config AUDIT_TREE
271 def_bool y
Eric Paris63c882a2009-05-21 17:02:01 -0400272 depends on AUDITSYSCALL
Eric Paris28a3a7e2009-12-17 20:12:05 -0500273 select FSNOTIFY
Al Viro74c3cbe2007-07-22 08:04:18 -0400274
Eric Paris633b4542012-01-03 14:23:08 -0500275config AUDIT_LOGINUID_IMMUTABLE
276 bool "Make audit loginuid immutable"
277 depends on AUDIT
278 help
Linus Torvaldsf429ee32012-01-17 16:06:51 -0800279 The config option toggles if a task setting its loginuid requires
Eric Paris633b4542012-01-03 14:23:08 -0500280 CAP_SYS_AUDITCONTROL or if that task should require no special permissions
281 but should instead only allow setting its loginuid if it was never
282 previously set. On systems which use systemd or a similar central
283 process to restart login services this should be set to true. On older
284 systems in which an admin would typically have to directly stop and
285 start processes this should be set to false. Setting this to true allows
286 one to drop potentially dangerous capabilites from the login tasks,
287 but may not be backwards compatible with older init systems.
288
Thomas Gleixnerd9817eb2010-09-27 12:45:59 +0000289source "kernel/irq/Kconfig"
Thomas Gleixner764e0da2012-05-21 23:16:18 +0200290source "kernel/time/Kconfig"
Thomas Gleixnerd9817eb2010-09-27 12:45:59 +0000291
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200292menu "CPU/Task time and stats accounting"
293
Frederic Weisbeckerabf917c2012-07-25 07:56:04 +0200294config VIRT_CPU_ACCOUNTING
295 bool
296
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200297choice
298 prompt "Cputime accounting"
299 default TICK_CPU_ACCOUNTING if !PPC64
Stephen Rothwell02fc8d32013-02-08 14:19:38 +1100300 default VIRT_CPU_ACCOUNTING_NATIVE if PPC64
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200301
302# Kind of a stub config for the pure tick based cputime accounting
303config TICK_CPU_ACCOUNTING
304 bool "Simple tick based cputime accounting"
Frederic Weisbeckerc58b0df2013-04-26 15:16:31 +0200305 depends on !S390 && !NO_HZ_FULL
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200306 help
307 This is the basic tick based cputime accounting that maintains
308 statistics about user, system and idle time spent on per jiffies
309 granularity.
310
311 If unsure, say Y.
312
Frederic Weisbeckerabf917c2012-07-25 07:56:04 +0200313config VIRT_CPU_ACCOUNTING_NATIVE
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200314 bool "Deterministic task and CPU time accounting"
Frederic Weisbeckerc58b0df2013-04-26 15:16:31 +0200315 depends on HAVE_VIRT_CPU_ACCOUNTING && !NO_HZ_FULL
Frederic Weisbeckerabf917c2012-07-25 07:56:04 +0200316 select VIRT_CPU_ACCOUNTING
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200317 help
318 Select this option to enable more accurate task and CPU time
319 accounting. This is done by reading a CPU counter on each
320 kernel entry and exit and on transitions within the kernel
321 between system, softirq and hardirq state, so there is a
322 small performance impact. In the case of s390 or IBM POWER > 5,
323 this also enables accounting of stolen time on logically-partitioned
324 systems.
325
Frederic Weisbeckerabf917c2012-07-25 07:56:04 +0200326config VIRT_CPU_ACCOUNTING_GEN
327 bool "Full dynticks CPU time accounting"
328 depends on HAVE_CONTEXT_TRACKING && 64BIT
329 select VIRT_CPU_ACCOUNTING
330 select CONTEXT_TRACKING
331 help
332 Select this option to enable task and CPU time accounting on full
333 dynticks systems. This accounting is implemented by watching every
334 kernel-user boundaries using the context tracking subsystem.
335 The accounting is thus performed at the expense of some significant
336 overhead.
337
338 For now this is only useful if you are working on the full
339 dynticks subsystem development.
340
341 If unsure, say N.
342
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200343config IRQ_TIME_ACCOUNTING
344 bool "Fine granularity task level IRQ time accounting"
Frederic Weisbeckerc58b0df2013-04-26 15:16:31 +0200345 depends on HAVE_IRQ_TIME_ACCOUNTING && !NO_HZ_FULL
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200346 help
347 Select this option to enable fine granularity task irq time
348 accounting. This is done by reading a timestamp on each
349 transitions between softirq and hardirq state, so there can be a
350 small performance impact.
351
352 If in doubt, say N here.
353
354endchoice
355
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200356config BSD_PROCESS_ACCT
357 bool "BSD Process Accounting"
358 help
359 If you say Y here, a user level program will be able to instruct the
360 kernel (via a special system call) to write process accounting
361 information to a file: whenever a process exits, information about
362 that process will be appended to the file by the kernel. The
363 information includes things such as creation time, owning user,
364 command name, memory usage, controlling terminal etc. (the complete
365 list is in the struct acct in <file:include/linux/acct.h>). It is
366 up to the user level program to do useful things with this
367 information. This is generally a good idea, so say Y.
368
369config BSD_PROCESS_ACCT_V3
370 bool "BSD Process Accounting version 3 file format"
371 depends on BSD_PROCESS_ACCT
372 default n
373 help
374 If you say Y here, the process accounting information is written
375 in a new file format that also logs the process IDs of each
376 process and it's parent. Note that this file format is incompatible
377 with previous v0/v1/v2 file formats, so you will need updated tools
378 for processing it. A preliminary version of these tools is available
379 at <http://www.gnu.org/software/acct/>.
380
381config TASKSTATS
Kees Cook19c92392012-10-02 11:19:29 -0700382 bool "Export task/process statistics through netlink"
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200383 depends on NET
384 default n
385 help
386 Export selected statistics for tasks/processes through the
387 generic netlink interface. Unlike BSD process accounting, the
388 statistics are available during the lifetime of tasks/processes as
389 responses to commands. Like BSD accounting, they are sent to user
390 space on task exit.
391
392 Say N if unsure.
393
394config TASK_DELAY_ACCT
Kees Cook19c92392012-10-02 11:19:29 -0700395 bool "Enable per-task delay accounting"
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200396 depends on TASKSTATS
397 help
398 Collect information on time spent by a task waiting for system
399 resources like cpu, synchronous block I/O completion and swapping
400 in pages. Such statistics can help in setting a task's priorities
401 relative to other tasks for cpu, io, rss limits etc.
402
403 Say N if unsure.
404
405config TASK_XACCT
Kees Cook19c92392012-10-02 11:19:29 -0700406 bool "Enable extended accounting over taskstats"
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200407 depends on TASKSTATS
408 help
409 Collect extended task accounting data and send the data
410 to userland for processing over the taskstats interface.
411
412 Say N if unsure.
413
414config TASK_IO_ACCOUNTING
Kees Cook19c92392012-10-02 11:19:29 -0700415 bool "Enable per-task storage I/O accounting"
Frederic Weisbecker391dc692012-09-09 14:22:07 +0200416 depends on TASK_XACCT
417 help
418 Collect information on the number of bytes of storage I/O which this
419 task has caused.
420
421 Say N if unsure.
422
423endmenu # "CPU/Task time and stats accounting"
424
Mike Travisc903ff82009-01-15 12:28:29 -0800425menu "RCU Subsystem"
426
427choice
428 prompt "RCU Implementation"
Paul E. McKenney31c9a242009-04-02 21:06:25 -0700429 default TREE_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800430
Mike Travisc903ff82009-01-15 12:28:29 -0800431config TREE_RCU
432 bool "Tree-based hierarchical RCU"
Paul E. McKenney687d7a92010-07-21 06:52:40 -0700433 depends on !PREEMPT && SMP
Steven Rostedt016a8d52013-05-28 17:32:53 -0400434 select IRQ_WORK
Mike Travisc903ff82009-01-15 12:28:29 -0800435 help
436 This option selects the RCU implementation that is
437 designed for very large SMP system with hundreds or
Paul E. McKenneyc17ef452009-06-23 17:12:47 -0700438 thousands of CPUs. It also scales down nicely to
439 smaller systems.
Mike Travisc903ff82009-01-15 12:28:29 -0800440
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700441config TREE_PREEMPT_RCU
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700442 bool "Preemptible tree-based hierarchical RCU"
Paul E. McKenney9fc52d82013-01-08 15:48:33 -0800443 depends on PREEMPT
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700444 help
445 This option selects the RCU implementation that is
446 designed for very large SMP systems with hundreds or
447 thousands of CPUs, but for which real-time response
Paul E. McKenneybbe3eae2009-09-13 09:15:08 -0700448 is also required. It also scales down nicely to
449 smaller systems.
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700450
Paul E. McKenney9fc52d82013-01-08 15:48:33 -0800451 Select this option if you are unsure.
452
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -0700453config TINY_RCU
454 bool "UP-only small-memory-footprint RCU"
Paul E. McKenney8008e122011-06-08 16:31:33 -0700455 depends on !PREEMPT && !SMP
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -0700456 help
457 This option selects the RCU implementation that is
458 designed for UP systems from which real-time response
459 is not required. This option greatly reduces the
460 memory footprint of RCU.
461
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700462config TINY_PREEMPT_RCU
463 bool "Preemptible UP-only small-memory-footprint RCU"
Paul E. McKenney8008e122011-06-08 16:31:33 -0700464 depends on PREEMPT && !SMP
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700465 help
466 This option selects the RCU implementation that is designed
467 for real-time UP systems. This option greatly reduces the
468 memory footprint of RCU.
469
Mike Travisc903ff82009-01-15 12:28:29 -0800470endchoice
471
Paul E. McKenneya57eb942010-06-29 16:49:16 -0700472config PREEMPT_RCU
473 def_bool ( TREE_PREEMPT_RCU || TINY_PREEMPT_RCU )
474 help
475 This option enables preemptible-RCU code that is common between
476 the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations.
477
Paul E. McKenney6bfc09e2012-10-19 12:49:17 -0700478config RCU_STALL_COMMON
479 def_bool ( TREE_RCU || TREE_PREEMPT_RCU || RCU_TRACE )
480 help
481 This option enables RCU CPU stall code that is common between
482 the TINY and TREE variants of RCU. The purpose is to allow
483 the tiny variants to disable RCU CPU stall warnings, while
484 making these warnings mandatory for the tree variants.
485
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100486config CONTEXT_TRACKING
487 bool
488
Frederic Weisbecker2b1d5022012-07-11 20:26:30 +0200489config RCU_USER_QS
490 bool "Consider userspace as in RCU extended quiescent state"
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100491 depends on HAVE_CONTEXT_TRACKING && SMP
492 select CONTEXT_TRACKING
Frederic Weisbecker2b1d5022012-07-11 20:26:30 +0200493 help
494 This option sets hooks on kernel / userspace boundaries and
495 puts RCU in extended quiescent state when the CPU runs in
496 userspace. It means that when a CPU runs in userspace, it is
497 excluded from the global RCU state machine and thus doesn't
Paul Gortmakeraf71bef2012-10-24 11:07:09 -0700498 try to keep the timer tick on for RCU.
Frederic Weisbecker2b1d5022012-07-11 20:26:30 +0200499
Frederic Weisbeckerd6771242012-10-11 01:48:28 +0200500 Unless you want to hack and help the development of the full
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100501 dynticks mode, you shouldn't enable this option. It also
Paul Gortmakeraf71bef2012-10-24 11:07:09 -0700502 adds unnecessary overhead.
Frederic Weisbeckerd6771242012-10-11 01:48:28 +0200503
504 If unsure say N
505
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100506config CONTEXT_TRACKING_FORCE
507 bool "Force context tracking"
508 depends on CONTEXT_TRACKING
Frederic Weisbecker8b438762013-02-26 15:37:59 +0100509 default CONTEXT_TRACKING
Frederic Weisbecker1fd2b442012-07-11 20:26:40 +0200510 help
Frederic Weisbecker91d1aa432012-11-27 19:33:25 +0100511 Probe on user/kernel boundaries by default in order to
512 test the features that rely on it such as userspace RCU extended
513 quiescent states.
514 This test is there for debugging until we have a real user like the
515 full dynticks mode.
Frederic Weisbeckerd6771242012-10-11 01:48:28 +0200516
Mike Travisc903ff82009-01-15 12:28:29 -0800517config RCU_FANOUT
518 int "Tree-based hierarchical RCU fanout value"
519 range 2 64 if 64BIT
520 range 2 32 if !64BIT
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700521 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800522 default 64 if 64BIT
523 default 32 if !64BIT
524 help
525 This option controls the fanout of hierarchical implementations
526 of RCU, allowing RCU to work efficiently on machines with
Paul E. McKenney4d87ffa2010-08-04 17:31:12 -0700527 large numbers of CPUs. This value must be at least the fourth
528 root of NR_CPUS, which allows NR_CPUS to be insanely large.
529 The default value of RCU_FANOUT should be used for production
530 systems, but if you are stress-testing the RCU implementation
531 itself, small RCU_FANOUT values allow you to test large-system
532 code paths on small(er) systems.
Mike Travisc903ff82009-01-15 12:28:29 -0800533
534 Select a specific number if testing RCU itself.
535 Take the default if unsure.
536
Paul E. McKenney8932a632012-04-19 12:20:14 -0700537config RCU_FANOUT_LEAF
538 int "Tree-based hierarchical RCU leaf-level fanout value"
539 range 2 RCU_FANOUT if 64BIT
540 range 2 RCU_FANOUT if !64BIT
541 depends on TREE_RCU || TREE_PREEMPT_RCU
542 default 16
543 help
544 This option controls the leaf-level fanout of hierarchical
545 implementations of RCU, and allows trading off cache misses
546 against lock contention. Systems that synchronize their
547 scheduling-clock interrupts for energy-efficiency reasons will
548 want the default because the smaller leaf-level fanout keeps
549 lock contention levels acceptably low. Very large systems
550 (hundreds or thousands of CPUs) will instead want to set this
551 value to the maximum value possible in order to reduce the
552 number of cache misses incurred during RCU's grace-period
553 initialization. These systems tend to run CPU-bound, and thus
554 are not helped by synchronized interrupts, and thus tend to
555 skew them, which reduces lock contention enough that large
556 leaf-level fanouts work well.
557
558 Select a specific number if testing RCU itself.
559
560 Select the maximum permissible value for large systems.
561
562 Take the default if unsure.
563
Mike Travisc903ff82009-01-15 12:28:29 -0800564config RCU_FANOUT_EXACT
565 bool "Disable tree-based hierarchical RCU auto-balancing"
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700566 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800567 default n
568 help
569 This option forces use of the exact RCU_FANOUT value specified,
570 regardless of imbalances in the hierarchy. This is useful for
571 testing RCU itself, and might one day be useful on systems with
572 strong NUMA behavior.
573
574 Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
575
576 Say N if unsure.
577
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800578config RCU_FAST_NO_HZ
579 bool "Accelerate last non-dyntick-idle CPU's grace periods"
Frederic Weisbecker3451d022011-08-10 23:21:01 +0200580 depends on NO_HZ_COMMON && SMP
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800581 default n
582 help
Paul E. McKenneyc0f4dfd2012-12-28 11:30:36 -0800583 This option permits CPUs to enter dynticks-idle state even if
584 they have RCU callbacks queued, and prevents RCU from waking
585 these CPUs up more than roughly once every four jiffies (by
586 default, you can adjust this using the rcutree.rcu_idle_gp_delay
587 parameter), thus improving energy efficiency. On the other
588 hand, this option increases the duration of RCU grace periods,
589 for example, slowing down synchronize_rcu().
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800590
Paul E. McKenneyc0f4dfd2012-12-28 11:30:36 -0800591 Say Y if energy efficiency is critically important, and you
592 don't care about increased grace-period durations.
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800593
594 Say N if you are unsure.
595
Mike Travisc903ff82009-01-15 12:28:29 -0800596config TREE_RCU_TRACE
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700597 def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
Mike Travisc903ff82009-01-15 12:28:29 -0800598 select DEBUG_FS
599 help
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700600 This option provides tracing for the TREE_RCU and
601 TREE_PREEMPT_RCU implementations, permitting Makefile to
602 trivially select kernel/rcutree_trace.c.
Mike Travisc903ff82009-01-15 12:28:29 -0800603
Paul E. McKenney24278d12010-09-27 17:25:23 -0700604config RCU_BOOST
605 bool "Enable RCU priority boosting"
Paul E. McKenney27f4d282011-02-07 12:47:15 -0800606 depends on RT_MUTEXES && PREEMPT_RCU
Paul E. McKenney24278d12010-09-27 17:25:23 -0700607 default n
608 help
609 This option boosts the priority of preempted RCU readers that
610 block the current preemptible RCU grace period for too long.
611 This option also prevents heavy loads from blocking RCU
612 callback invocation for all flavors of RCU.
613
614 Say Y here if you are working with real-time apps or heavy loads
615 Say N here if you are unsure.
616
617config RCU_BOOST_PRIO
618 int "Real-time priority to boost RCU readers to"
619 range 1 99
620 depends on RCU_BOOST
621 default 1
622 help
Paul E. McKenneyc9336642012-04-18 16:20:18 -0700623 This option specifies the real-time priority to which long-term
624 preempted RCU readers are to be boosted. If you are working
625 with a real-time application that has one or more CPU-bound
626 threads running at a real-time priority level, you should set
627 RCU_BOOST_PRIO to a priority higher then the highest-priority
628 real-time CPU-bound thread. The default RCU_BOOST_PRIO value
629 of 1 is appropriate in the common case, which is real-time
630 applications that do not have any CPU-bound threads.
631
632 Some real-time applications might not have a single real-time
633 thread that saturates a given CPU, but instead might have
634 multiple real-time threads that, taken together, fully utilize
635 that CPU. In this case, you should set RCU_BOOST_PRIO to
636 a priority higher than the lowest-priority thread that is
637 conspiring to prevent the CPU from running any non-real-time
638 tasks. For example, if one thread at priority 10 and another
639 thread at priority 5 are between themselves fully consuming
640 the CPU time on a given CPU, then RCU_BOOST_PRIO should be
641 set to priority 6 or higher.
Paul E. McKenney24278d12010-09-27 17:25:23 -0700642
643 Specify the real-time priority, or take the default if unsure.
644
645config RCU_BOOST_DELAY
646 int "Milliseconds to delay boosting after RCU grace-period start"
647 range 0 3000
648 depends on RCU_BOOST
649 default 500
650 help
651 This option specifies the time to wait after the beginning of
652 a given grace period before priority-boosting preempted RCU
653 readers blocking that grace period. Note that any RCU reader
654 blocking an expedited RCU grace period is boosted immediately.
655
656 Accept the default if unsure.
657
Paul E. McKenney3fbfbf72012-08-19 21:35:53 -0700658config RCU_NOCB_CPU
Paul E. McKenney9a5739d2013-03-28 20:48:36 -0700659 bool "Offload RCU callback processing from boot-selected CPUs"
Paul E. McKenney3fbfbf72012-08-19 21:35:53 -0700660 depends on TREE_RCU || TREE_PREEMPT_RCU
661 default n
662 help
663 Use this option to reduce OS jitter for aggressive HPC or
664 real-time workloads. It can also be used to offload RCU
665 callback invocation to energy-efficient CPUs in battery-powered
666 asymmetric multiprocessors.
667
668 This option offloads callback invocation from the set of
669 CPUs specified at boot time by the rcu_nocbs parameter.
Paul E. McKenneya4889852012-12-03 08:16:28 -0800670 For each such CPU, a kthread ("rcuox/N") will be created to
671 invoke callbacks, where the "N" is the CPU being offloaded,
672 and where the "x" is "b" for RCU-bh, "p" for RCU-preempt, and
673 "s" for RCU-sched. Nothing prevents this kthread from running
674 on the specified CPUs, but (1) the kthreads may be preempted
675 between each callback, and (2) affinity or cgroups can be used
676 to force the kthreads to run on whatever set of CPUs is desired.
Paul E. McKenney3fbfbf72012-08-19 21:35:53 -0700677
Paul E. McKenney34ed62462013-01-07 13:37:42 -0800678 Say Y here if you want to help to debug reduced OS jitter.
Paul E. McKenney3fbfbf72012-08-19 21:35:53 -0700679 Say N here if you are unsure.
680
Paul E. McKenney911af502013-02-11 10:23:27 -0800681choice
682 prompt "Build-forced no-CBs CPUs"
683 default RCU_NOCB_CPU_NONE
684 help
685 This option allows no-CBs CPUs to be specified at build time.
686 Additional no-CBs CPUs may be specified by the rcu_nocbs=
687 boot parameter.
688
689config RCU_NOCB_CPU_NONE
690 bool "No build_forced no-CBs CPUs"
Frederic Weisbecker73c30822013-05-03 01:28:12 +0200691 depends on RCU_NOCB_CPU && !NO_HZ_FULL
Paul E. McKenney911af502013-02-11 10:23:27 -0800692 help
693 This option does not force any of the CPUs to be no-CBs CPUs.
694 Only CPUs designated by the rcu_nocbs= boot parameter will be
695 no-CBs CPUs.
696
697config RCU_NOCB_CPU_ZERO
698 bool "CPU 0 is a build_forced no-CBs CPU"
Frederic Weisbecker73c30822013-05-03 01:28:12 +0200699 depends on RCU_NOCB_CPU && !NO_HZ_FULL
Paul E. McKenney911af502013-02-11 10:23:27 -0800700 help
701 This option forces CPU 0 to be a no-CBs CPU. Additional CPUs
702 may be designated as no-CBs CPUs using the rcu_nocbs= boot
703 parameter will be no-CBs CPUs.
704
705 Select this if CPU 0 needs to be a no-CBs CPU for real-time
706 or energy-efficiency reasons.
707
708config RCU_NOCB_CPU_ALL
709 bool "All CPUs are build_forced no-CBs CPUs"
710 depends on RCU_NOCB_CPU
711 help
712 This option forces all CPUs to be no-CBs CPUs. The rcu_nocbs=
713 boot parameter will be ignored.
714
715 Select this if all CPUs need to be no-CBs CPUs for real-time
716 or energy-efficiency reasons.
717
718endchoice
719
Mike Travisc903ff82009-01-15 12:28:29 -0800720endmenu # "RCU Subsystem"
721
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700723 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724 ---help---
725 This option enables the complete Linux kernel ".config" file
726 contents to be saved in the kernel. It provides documentation
727 of which kernel options are used in a running kernel or in an
728 on-disk kernel. This information can be extracted from the kernel
729 image file with the script scripts/extract-ikconfig and used as
730 input to rebuild the current kernel or to build another kernel.
731 It can also be extracted from a running kernel by reading
732 /proc/config.gz if enabled (below).
733
734config IKCONFIG_PROC
735 bool "Enable access to .config through /proc/config.gz"
736 depends on IKCONFIG && PROC_FS
737 ---help---
738 This option enables access to the kernel configuration file
739 through /proc/config.gz.
740
Alistair John Strachan794543a2007-05-08 00:31:15 -0700741config LOG_BUF_SHIFT
742 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
743 range 12 21
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700744 default 17
Alistair John Strachan794543a2007-05-08 00:31:15 -0700745 help
746 Select kernel log buffer size as a power of 2.
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700747 Examples:
748 17 => 128 KB
749 16 => 64 KB
750 15 => 32 KB
751 14 => 16 KB
Alistair John Strachan794543a2007-05-08 00:31:15 -0700752 13 => 8 KB
753 12 => 4 KB
754
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800755#
756# Architectures with an unreliable sched_clock() should select this:
757#
758config HAVE_UNSTABLE_SCHED_CLOCK
759 bool
760
Andrea Arcangelibe3a7282012-10-04 01:50:47 +0200761#
762# For architectures that want to enable the support for NUMA-affine scheduler
763# balancing logic:
764#
765config ARCH_SUPPORTS_NUMA_BALANCING
766 bool
767
768# For architectures that (ab)use NUMA to represent different memory regions
769# all cpu-local but of different latencies, such as SuperH.
770#
771config ARCH_WANT_NUMA_VARIABLE_LOCALITY
772 bool
773
774#
775# For architectures that are willing to define _PAGE_NUMA as _PAGE_PROTNONE
776config ARCH_WANTS_PROT_NUMA_PROT_NONE
777 bool
778
779config ARCH_USES_NUMA_PROT_NONE
780 bool
781 default y
782 depends on ARCH_WANTS_PROT_NUMA_PROT_NONE
783 depends on NUMA_BALANCING
784
Mel Gorman1a687c22012-11-22 11:16:36 +0000785config NUMA_BALANCING_DEFAULT_ENABLED
786 bool "Automatically enable NUMA aware memory/task placement"
787 default y
788 depends on NUMA_BALANCING
789 help
790 If set, autonumic NUMA balancing will be enabled if running on a NUMA
791 machine.
792
Andrea Arcangelibe3a7282012-10-04 01:50:47 +0200793config NUMA_BALANCING
794 bool "Memory placement aware NUMA scheduler"
Andrea Arcangelibe3a7282012-10-04 01:50:47 +0200795 depends on ARCH_SUPPORTS_NUMA_BALANCING
796 depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY
797 depends on SMP && NUMA && MIGRATION
798 help
799 This option adds support for automatic NUMA aware memory/task placement.
800 The mechanism is quite primitive and is based on migrating memory when
801 it is references to the node the task is running on.
802
803 This system will be inactive on UMA systems.
804
Li Zefan23964d22009-01-15 13:50:58 -0800805menuconfig CGROUPS
806 boolean "Control Group support"
Kirill A. Shutemov0dea1162010-03-10 15:22:20 -0800807 depends on EVENTFD
Paul Menageddbcc7e2007-10-18 23:39:30 -0700808 help
Li Zefan23964d22009-01-15 13:50:58 -0800809 This option adds support for grouping sets of processes together, for
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800810 use with process control subsystems such as Cpusets, CFS, memory
811 controls or device isolation.
812 See
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800813 - Documentation/scheduler/sched-design-CFS.txt (CFS)
Li Zefan45ce80f2009-01-15 13:50:59 -0800814 - Documentation/cgroups/ (features for grouping, isolation
815 and resource control)
Paul Menageddbcc7e2007-10-18 23:39:30 -0700816
817 Say N if unsure.
818
Li Zefan23964d22009-01-15 13:50:58 -0800819if CGROUPS
820
Paul Menage006cb992007-10-18 23:39:43 -0700821config CGROUP_DEBUG
822 bool "Example debug cgroup subsystem"
Paul Menage418d7d82008-04-29 01:00:05 -0700823 default n
Paul Menage006cb992007-10-18 23:39:43 -0700824 help
825 This option enables a simple cgroup subsystem that
826 exports useful debugging information about the cgroups
Li Zefan23964d22009-01-15 13:50:58 -0800827 framework.
Paul Menage006cb992007-10-18 23:39:43 -0700828
Li Zefan23964d22009-01-15 13:50:58 -0800829 Say N if unsure.
Paul Menage006cb992007-10-18 23:39:43 -0700830
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700831config CGROUP_FREEZER
Li Zefan23964d22009-01-15 13:50:58 -0800832 bool "Freezer cgroup subsystem"
Li Zefan23964d22009-01-15 13:50:58 -0800833 help
834 Provides a way to freeze and unfreeze all tasks in a
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700835 cgroup.
836
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700837config CGROUP_DEVICE
838 bool "Device controller for cgroups"
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700839 help
840 Provides a cgroup implementing whitelists for devices which
841 a process in the cgroup can mknod or open.
842
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843config CPUSETS
844 bool "Cpuset support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700846 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847 allow dynamically partitioning a system into sets of CPUs and
848 Memory Nodes and assigning tasks to run only within those sets.
849 This is primarily useful on large SMP or NUMA systems.
850
851 Say N if unsure.
852
Li Zefan23964d22009-01-15 13:50:58 -0800853config PROC_PID_CPUSET
854 bool "Include legacy /proc/<pid>/cpuset file"
855 depends on CPUSETS
856 default y
857
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100858config CGROUP_CPUACCT
859 bool "Simple CPU accounting cgroup subsystem"
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100860 help
861 Provides a simple Resource Controller for monitoring the
Li Zefan23964d22009-01-15 13:50:58 -0800862 total CPU consumed by the tasks in a cgroup.
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100863
Pavel Emelianove552b662008-02-07 00:13:49 -0800864config RESOURCE_COUNTERS
865 bool "Resource counters"
866 help
867 This option enables controller independent resource accounting
Li Zefan23964d22009-01-15 13:50:58 -0800868 infrastructure that works with cgroups.
Pavel Emelianove552b662008-02-07 00:13:49 -0800869
Andrew Mortonc255a452012-07-31 16:43:02 -0700870config MEMCG
Balbir Singh00f0b822008-03-04 14:28:39 -0800871 bool "Memory Resource Controller for Control Groups"
Daniel Lezcano79ae9c22010-10-27 15:34:39 -0700872 depends on RESOURCE_COUNTERS
Balbir Singhcf475ad2008-04-29 01:00:16 -0700873 select MM_OWNER
Balbir Singh00f0b822008-03-04 14:28:39 -0800874 help
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700875 Provides a memory resource controller that manages both anonymous
Thadeu Lima de Souza Cascardo21acb9c2009-02-04 10:12:08 +0100876 memory and page cache. (See Documentation/cgroups/memory.txt)
Balbir Singh00f0b822008-03-04 14:28:39 -0800877
878 Note that setting this option increases fixed memory overhead
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700879 associated with each page of memory in the system. By this,
880 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
881 usage tracking struct at boot. Total amount of this is printed out
882 at boot.
Balbir Singh00f0b822008-03-04 14:28:39 -0800883
884 Only enable when you're ok with these trade offs and really
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700885 sure you need the memory resource controller. Even when you enable
886 this, you can set "cgroup_disable=memory" at your boot option to
887 disable memory resource controller and you can avoid overheads.
Li Zefanc9d54092009-01-07 18:07:35 -0800888 (and lose benefits of memory resource controller)
Balbir Singh00f0b822008-03-04 14:28:39 -0800889
Balbir Singhcf475ad2008-04-29 01:00:16 -0700890 This config option also selects MM_OWNER config option, which
891 could in turn add some fork/exit overhead.
892
Andrew Mortonc255a452012-07-31 16:43:02 -0700893config MEMCG_SWAP
KAMEZAWA Hiroyuki65e0e812010-08-10 18:02:56 -0700894 bool "Memory Resource Controller Swap Extension"
Andrew Mortonc255a452012-07-31 16:43:02 -0700895 depends on MEMCG && SWAP
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800896 help
897 Add swap management feature to memory resource controller. When you
898 enable this, you can limit mem+swap usage per cgroup. In other words,
899 when you disable this, memory resource controller has no cares to
900 usage of swap...a process can exhaust all of the swap. This extension
901 is useful when you want to avoid exhaustion swap but this itself
902 adds more overheads and consumes memory for remembering information.
903 Especially if you use 32bit system or small memory system, please
904 be careful about enabling this. When memory resource controller
905 is disabled by boot option, this will be automatically disabled and
906 there will be no overhead from this. Even when you set this config=y,
WANG Cong00a66d22011-07-25 17:12:12 -0700907 if boot option "swapaccount=0" is set, swap will not be accounted.
KAMEZAWA Hiroyuki627991a2009-04-02 16:57:47 -0700908 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
909 size is 4096bytes, 512k per 1Gbytes of swap.
Andrew Mortonc255a452012-07-31 16:43:02 -0700910config MEMCG_SWAP_ENABLED
Michal Hockoa42c3902010-11-24 12:57:08 -0800911 bool "Memory Resource Controller Swap Extension enabled by default"
Andrew Mortonc255a452012-07-31 16:43:02 -0700912 depends on MEMCG_SWAP
Michal Hockoa42c3902010-11-24 12:57:08 -0800913 default y
914 help
915 Memory Resource Controller Swap Extension comes with its price in
916 a bigger memory consumption. General purpose distribution kernels
Jim Cromie43d547f2010-12-17 14:32:36 -0700917 which want to enable the feature but keep it disabled by default
Michal Hockoa42c3902010-11-24 12:57:08 -0800918 and let the user enable it by swapaccount boot command line
919 parameter should have this option unselected.
920 For those who want to have the feature enabled by default should
921 select this option (if, for some reason, they need to disable it
WANG Cong00a66d22011-07-25 17:12:12 -0700922 then swapaccount=0 does the trick).
Andrew Mortonc255a452012-07-31 16:43:02 -0700923config MEMCG_KMEM
Kees Cook19c92392012-10-02 11:19:29 -0700924 bool "Memory Resource Controller Kernel Memory accounting"
925 depends on MEMCG
Glauber Costa510fc4e2012-12-18 14:21:47 -0800926 depends on SLUB || SLAB
Glauber Costae5671df2011-12-11 21:47:01 +0000927 help
928 The Kernel Memory extension for Memory Resource Controller can limit
929 the amount of memory used by kernel objects in the system. Those are
930 fundamentally different from the entities handled by the standard
931 Memory Controller, which are page-based, and can be swapped. Users of
932 the kmem extension can use it to guarantee that no group of processes
933 will ever exhaust kernel resources alone.
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800934
Aneesh Kumar K.V2bc64a22012-07-31 16:42:12 -0700935config CGROUP_HUGETLB
936 bool "HugeTLB Resource Controller for Control Groups"
Kees Cook19c92392012-10-02 11:19:29 -0700937 depends on RESOURCE_COUNTERS && HUGETLB_PAGE
Aneesh Kumar K.V2bc64a22012-07-31 16:42:12 -0700938 default n
939 help
940 Provides a cgroup Resource Controller for HugeTLB pages.
941 When you enable this, you can put a per cgroup limit on HugeTLB usage.
942 The limit is enforced during page fault. Since HugeTLB doesn't
943 support page reclaim, enforcing the limit at page fault time implies
944 that, the application will get SIGBUS signal if it tries to access
945 HugeTLB pages beyond its limit. This requires the application to know
946 beforehand how much HugeTLB pages it would require for its use. The
947 control group is tracked in the third page lru pointer. This means
948 that we cannot use the controller with huge page less than 3 pages.
949
Stephane Eraniane5d13672011-02-14 11:20:01 +0200950config CGROUP_PERF
951 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
952 depends on PERF_EVENTS && CGROUPS
953 help
954 This option extends the per-cpu mode to restrict monitoring to
Li Zefan2d0f2522011-03-03 14:26:20 +0800955 threads which belong to the cgroup specified and run on the
Stephane Eraniane5d13672011-02-14 11:20:01 +0200956 designated cpu.
957
958 Say N if unsure.
959
Dhaval Giani7c941432010-01-20 13:26:18 +0100960menuconfig CGROUP_SCHED
961 bool "Group CPU scheduler"
Dhaval Giani7c941432010-01-20 13:26:18 +0100962 default n
963 help
964 This feature lets CPU scheduler recognize task groups and control CPU
965 bandwidth allocation to such task groups. It uses cgroups to group
966 tasks.
967
968if CGROUP_SCHED
969config FAIR_GROUP_SCHED
970 bool "Group scheduling for SCHED_OTHER"
971 depends on CGROUP_SCHED
972 default CGROUP_SCHED
973
Paul Turnerab84d312011-07-21 09:43:28 -0700974config CFS_BANDWIDTH
975 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
Paul Turnerab84d312011-07-21 09:43:28 -0700976 depends on FAIR_GROUP_SCHED
977 default n
978 help
979 This option allows users to define CPU bandwidth rates (limits) for
980 tasks running within the fair group scheduler. Groups with no limit
981 set are considered to be unconstrained and will run with no
982 restriction.
983 See tip/Documentation/scheduler/sched-bwc.txt for more information.
984
Dhaval Giani7c941432010-01-20 13:26:18 +0100985config RT_GROUP_SCHED
986 bool "Group scheduling for SCHED_RR/FIFO"
Dhaval Giani7c941432010-01-20 13:26:18 +0100987 depends on CGROUP_SCHED
988 default n
989 help
990 This feature lets you explicitly allocate real CPU bandwidth
Li Zefan32bd7eb2010-03-24 13:17:19 +0800991 to task groups. If enabled, it will also make it impossible to
Dhaval Giani7c941432010-01-20 13:26:18 +0100992 schedule realtime tasks for non-root users until you allocate
993 realtime bandwidth for them.
994 See Documentation/scheduler/sched-rt-group.txt for more information.
995
996endif #CGROUP_SCHED
997
Vivek Goyalafc24d42010-04-26 19:27:56 +0200998config BLK_CGROUP
Tejun Heo32e380a2012-03-05 13:14:54 -0800999 bool "Block IO controller"
Daniel Lezcano79ae9c22010-10-27 15:34:39 -07001000 depends on BLOCK
Vivek Goyalafc24d42010-04-26 19:27:56 +02001001 default n
1002 ---help---
1003 Generic block IO controller cgroup interface. This is the common
1004 cgroup interface which should be used by various IO controlling
1005 policies.
1006
1007 Currently, CFQ IO scheduler uses it to recognize task groups and
1008 control disk bandwidth allocation (proportional time slice allocation)
Vivek Goyale43473b2010-09-15 17:06:35 -04001009 to such task groups. It is also used by bio throttling logic in
1010 block layer to implement upper limit in IO rates on a device.
Vivek Goyalafc24d42010-04-26 19:27:56 +02001011
1012 This option only enables generic Block IO controller infrastructure.
Vivek Goyale43473b2010-09-15 17:06:35 -04001013 One needs to also enable actual IO controlling logic/policy. For
Michael Witten79e2e752011-01-16 21:43:10 +00001014 enabling proportional weight division of disk bandwidth in CFQ, set
1015 CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
Michael Wittenc5e05912011-01-17 00:08:41 +00001016 CONFIG_BLK_DEV_THROTTLING=y.
Vivek Goyalafc24d42010-04-26 19:27:56 +02001017
1018 See Documentation/cgroups/blkio-controller.txt for more information.
1019
1020config DEBUG_BLK_CGROUP
1021 bool "Enable Block IO controller debugging"
1022 depends on BLK_CGROUP
1023 default n
1024 ---help---
1025 Enable some debugging help. Currently it exports additional stat
1026 files in a cgroup which can be useful for debugging.
1027
Li Zefan23964d22009-01-15 13:50:58 -08001028endif # CGROUPS
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -08001029
Cyrill Gorcunov067bce12012-01-12 17:20:49 -08001030config CHECKPOINT_RESTORE
1031 bool "Checkpoint/restore support" if EXPERT
1032 default n
1033 help
1034 Enables additional kernel features in a sake of checkpoint/restore.
1035 In particular it adds auxiliary prctl codes to setup process text,
1036 data and heap segment sizes, and a few additional /proc filesystem
1037 entries.
1038
1039 If unsure, say N here.
1040
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001041menuconfig NAMESPACES
David Rientjes6a108a12011-01-20 14:44:16 -08001042 bool "Namespaces support" if EXPERT
1043 default !EXPERT
Pavel Emelyanovc5289a62008-02-08 04:18:19 -08001044 help
1045 Provides the way to make tasks work with different objects using
1046 the same id. For example same IPC id may refer to different objects
1047 or same user id or pid may refer to different tasks when used in
1048 different namespaces.
1049
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001050if NAMESPACES
1051
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -08001052config UTS_NS
1053 bool "UTS namespace"
Daniel Lezcano17a6d442010-10-27 15:34:37 -07001054 default y
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -08001055 help
1056 In this namespace tasks see different info provided with the
1057 uname() system call
1058
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -08001059config IPC_NS
1060 bool "IPC namespace"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001061 depends on (SYSVIPC || POSIX_MQUEUE)
Daniel Lezcano17a6d442010-10-27 15:34:37 -07001062 default y
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -08001063 help
1064 In this namespace tasks work with IPC ids which correspond to
Serge E. Hallyn614b84c2009-04-06 19:01:08 -07001065 different IPC objects in different namespaces.
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -08001066
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -08001067config USER_NS
Kees Cook19c92392012-10-02 11:19:29 -07001068 bool "User namespace"
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001069 depends on UIDGID_CONVERTED
Eric W. Biederman5673a942011-11-17 10:23:55 -08001070 select UIDGID_STRICT_TYPE_CHECKS
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001071
Eric W. Biederman5673a942011-11-17 10:23:55 -08001072 default n
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -08001073 help
1074 This allows containers, i.e. vservers, to use user namespaces
1075 to provide different user info for different servers.
Eric W. Biedermane11f0ae2013-01-25 16:48:31 -08001076
1077 When user namespaces are enabled in the kernel it is
1078 recommended that the MEMCG and MEMCG_KMEM options also be
1079 enabled and that user-space use the memory control groups to
1080 limit the amount of memory a memory unprivileged users can
1081 use.
1082
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -08001083 If unsure, say N.
1084
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -08001085config PID_NS
Daniel Lezcano9bd38c22010-10-27 15:34:37 -07001086 bool "PID Namespaces"
Daniel Lezcano17a6d442010-10-27 15:34:37 -07001087 default y
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -08001088 help
Heikki Orsila12d2b8f2008-07-06 15:48:02 +03001089 Support process id namespaces. This allows having multiple
Matt LaPlante692105b2009-01-26 11:12:25 +01001090 processes with the same pid as long as they are in different
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -08001091 pid namespaces. This is a building block of containers.
1092
Matt Helsleyd6eb6332009-01-26 12:25:55 -08001093config NET_NS
1094 bool "Network namespace"
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001095 depends on NET
Daniel Lezcano17a6d442010-10-27 15:34:37 -07001096 default y
Matt Helsleyd6eb6332009-01-26 12:25:55 -08001097 help
1098 Allow user space to create what appear to be multiple instances
1099 of the network stack.
1100
Daniel Lezcano8dd2a822010-10-27 15:34:38 -07001101endif # NAMESPACES
1102
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001103config UIDGID_CONVERTED
1104 # True if all of the selected software conmponents are known
1105 # to have uid_t and gid_t converted to kuid_t and kgid_t
1106 # where appropriate and are otherwise safe to use with
1107 # the user namespace.
1108 bool
1109 default y
1110
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001111 # Filesystems
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001112 depends on XFS_FS = n
1113
Eric W. Biederman5673a942011-11-17 10:23:55 -08001114config UIDGID_STRICT_TYPE_CHECKS
1115 bool "Require conversions between uid/gids and their internal representation"
Eric W. Biedermane1c972b2012-04-21 04:09:01 -07001116 depends on UIDGID_CONVERTED
Eric W. Biederman5673a942011-11-17 10:23:55 -08001117 default n
1118 help
1119 While the nececessary conversions are being added to all subsystems this option allows
1120 the code to continue to build for unconverted subsystems.
1121
1122 Say Y here if you want the strict type checking enabled
1123
Mike Galbraith5091faa2010-11-30 14:18:03 +01001124config SCHED_AUTOGROUP
1125 bool "Automatic process group scheduling"
1126 select EVENTFD
1127 select CGROUPS
1128 select CGROUP_SCHED
1129 select FAIR_GROUP_SCHED
1130 help
1131 This option optimizes the scheduler for common desktop workloads by
1132 automatically creating and populating task groups. This separation
1133 of workloads isolates aggressive CPU burners (like build jobs) from
1134 desktop applications. Task group autogeneration is currently based
1135 upon task session.
1136
Daniel Lezcano7af37be2010-10-27 15:34:41 -07001137config MM_OWNER
1138 bool
1139
1140config SYSFS_DEPRECATED
Ferenc Wagner5d6a4ea2011-01-10 19:04:22 +01001141 bool "Enable deprecated sysfs features to support old userspace tools"
Daniel Lezcano7af37be2010-10-27 15:34:41 -07001142 depends on SYSFS
1143 default n
1144 help
1145 This option adds code that switches the layout of the "block" class
1146 devices, to not show up in /sys/class/block/, but only in
1147 /sys/block/.
1148
1149 This switch is only active when the sysfs.deprecated=1 boot option is
1150 passed or the SYSFS_DEPRECATED_V2 option is set.
1151
1152 This option allows new kernels to run on old distributions and tools,
1153 which might get confused by /sys/class/block/. Since 2007/2008 all
1154 major distributions and tools handle this just fine.
1155
1156 Recent distributions and userspace tools after 2009/2010 depend on
1157 the existence of /sys/class/block/, and will not work with this
1158 option enabled.
1159
1160 Only if you are using a new kernel on an old distribution, you might
1161 need to say Y here.
1162
1163config SYSFS_DEPRECATED_V2
Ferenc Wagner5d6a4ea2011-01-10 19:04:22 +01001164 bool "Enable deprecated sysfs features by default"
Daniel Lezcano7af37be2010-10-27 15:34:41 -07001165 default n
1166 depends on SYSFS
1167 depends on SYSFS_DEPRECATED
1168 help
1169 Enable deprecated sysfs by default.
1170
1171 See the CONFIG_SYSFS_DEPRECATED option for more details about this
1172 option.
1173
1174 Only if you are using a new kernel on an old distribution, you might
1175 need to say Y here. Even then, odds are you would not need it
1176 enabled, you can always pass the boot option if absolutely necessary.
1177
1178config RELAY
1179 bool "Kernel->user space relay support (formerly relayfs)"
1180 help
1181 This option enables support for relay interface support in
1182 certain file systems (such as debugfs).
1183 It is designed to provide an efficient mechanism for tools and
1184 facilities to relay large amounts of data from kernel space to
1185 user space.
1186
1187 If unsure, say N.
1188
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -08001189config BLK_DEV_INITRD
1190 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
1191 depends on BROKEN || !FRV
1192 help
1193 The initial RAM filesystem is a ramfs which is loaded by the
1194 boot loader (loadlin or lilo) and that is mounted as root
1195 before the normal boot procedure. It is typically used to
1196 load modules needed to mount the "real" root file system,
1197 etc. See <file:Documentation/initrd.txt> for details.
1198
1199 If RAM disk support (BLK_DEV_RAM) is also included, this
1200 also enables initial RAM disk (initrd) support and adds
1201 15 Kbytes (more on some other architectures) to the kernel size.
1202
1203 If unsure say Y.
1204
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -08001205if BLK_DEV_INITRD
1206
Sam Ravnborgdbec4862005-08-10 20:44:50 +02001207source "usr/Kconfig"
1208
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -08001209endif
1210
Linus Torvaldsc45b4f12005-12-14 18:52:21 -08001211config CC_OPTIMIZE_FOR_SIZE
Ingo Molnar96fffeb2008-04-28 01:39:43 +02001212 bool "Optimize for size"
Linus Torvaldsc45b4f12005-12-14 18:52:21 -08001213 help
1214 Enabling this option will pass "-Os" instead of "-O2" to gcc
1215 resulting in a smaller kernel.
1216
Kirill Smelkov3a55fb02012-11-02 15:41:01 +04001217 If unsure, say N.
Linus Torvaldsc45b4f12005-12-14 18:52:21 -08001218
Randy Dunlap08470622006-09-30 23:28:13 -07001219config SYSCTL
1220 bool
1221
Randy Dunlapb943c462009-03-10 12:55:46 -07001222config ANON_INODES
1223 bool
1224
Mike Frysinger657a5202013-04-30 15:28:45 -07001225config HAVE_UID16
1226 bool
1227
1228config SYSCTL_EXCEPTION_TRACE
1229 bool
1230 help
1231 Enable support for /proc/sys/debug/exception-trace.
1232
1233config SYSCTL_ARCH_UNALIGN_NO_WARN
1234 bool
1235 help
1236 Enable support for /proc/sys/kernel/ignore-unaligned-usertrap
1237 Allows arch to define/use @no_unaligned_warning to possibly warn
1238 about unaligned access emulation going on under the hood.
1239
1240config SYSCTL_ARCH_UNALIGN_ALLOW
1241 bool
1242 help
1243 Enable support for /proc/sys/kernel/unaligned-trap
1244 Allows arches to define/use @unaligned_enabled to runtime toggle
1245 the unaligned access emulation.
1246 see arch/parisc/kernel/unaligned.c for reference
1247
1248config HOTPLUG
1249 def_bool y
1250
1251config HAVE_PCSPKR_PLATFORM
1252 bool
1253
David Rientjes6a108a12011-01-20 14:44:16 -08001254menuconfig EXPERT
1255 bool "Configure standard kernel features (expert users)"
Josh Triplettf505c552011-06-05 18:23:58 -07001256 # Unhide debug options, to make the on-by-default options visible
1257 select DEBUG_KERNEL
Linus Torvalds1da177e2005-04-16 15:20:36 -07001258 help
1259 This option allows certain base kernel options and settings
1260 to be disabled or tweaked. This is for specialized
1261 environments which can tolerate a "non-standard" kernel.
1262 Only use this if you really know what you are doing.
1263
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001264config UID16
David Rientjes6a108a12011-01-20 14:44:16 -08001265 bool "Enable 16-bit UID system calls" if EXPERT
Catalin Marinasaf1839e2012-10-08 16:28:08 -07001266 depends on HAVE_UID16
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001267 default y
1268 help
1269 This enables the legacy 16-bit UID syscall wrappers.
1270
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001271config SYSCTL_SYSCALL
David Rientjes6a108a12011-01-20 14:44:16 -08001272 bool "Sysctl syscall support" if EXPERT
Eric W. Biederman26a70342009-11-05 05:26:41 -08001273 depends on PROC_SYSCTL
WANG Congc736de62011-11-02 13:39:25 -07001274 default n
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001275 select SYSCTL
1276 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -08001277 sys_sysctl uses binary paths that have been found challenging
1278 to properly maintain and use. The interface in /proc/sys
1279 using paths with ascii names is now the primary path to this
1280 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001281
Eric W. Biederman13bb7e32006-11-08 17:44:51 -08001282 Almost nothing using the binary sysctl interface so if you are
1283 trying to save some space it is probably safe to disable this,
1284 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -07001285
WANG Congc736de62011-11-02 13:39:25 -07001286 If unsure say N here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001287
Linus Torvalds1da177e2005-04-16 15:20:36 -07001288config KALLSYMS
David Rientjes6a108a12011-01-20 14:44:16 -08001289 bool "Load all symbols for debugging/ksymoops" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001290 default y
1291 help
1292 Say Y here to let the kernel print out symbolic crash information and
1293 symbolic stack backtraces. This increases the size of the kernel
1294 somewhat, as all symbols have to be loaded into the kernel image.
1295
1296config KALLSYMS_ALL
1297 bool "Include all symbols in kallsyms"
1298 depends on DEBUG_KERNEL && KALLSYMS
1299 help
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001300 Normally kallsyms only contains the symbols of functions for nicer
1301 OOPS messages and backtraces (i.e., symbols from the text and inittext
1302 sections). This is sufficient for most cases. And only in very rare
1303 cases (e.g., when a debugger is used) all symbols are required (e.g.,
1304 names of variables from the data sections, etc).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001305
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001306 This option makes sure that all symbols are loaded into the kernel
1307 image (i.e., symbols from all sections) in cost of increased kernel
1308 size (depending on the kernel configuration, it may be 300KiB or
1309 something like this).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001310
Artem Bityutskiy71a83ec2011-04-05 13:24:57 +03001311 Say N unless you really need all symbols.
Matt Mackalld59745c2005-05-01 08:59:02 -07001312
1313config PRINTK
1314 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001315 bool "Enable support for printk" if EXPERT
Frederic Weisbecker74876a92012-10-12 18:00:23 +02001316 select IRQ_WORK
Matt Mackalld59745c2005-05-01 08:59:02 -07001317 help
1318 This option enables normal printk support. Removing it
1319 eliminates most of the message strings from the kernel image
1320 and makes the kernel more or less silent. As this makes it
1321 very difficult to diagnose system problems, saying N here is
1322 strongly discouraged.
1323
Matt Mackallc8538a72005-05-01 08:59:01 -07001324config BUG
David Rientjes6a108a12011-01-20 14:44:16 -08001325 bool "BUG() support" if EXPERT
Matt Mackallc8538a72005-05-01 08:59:01 -07001326 default y
1327 help
1328 Disabling this option eliminates support for BUG and WARN, reducing
1329 the size of your kernel image and potentially quietly ignoring
1330 numerous fatal conditions. You should only consider disabling this
1331 option for embedded systems with no facilities for reporting errors.
1332 Just say Y.
1333
Matt Mackall708e9a72006-01-08 01:05:25 -08001334config ELF_CORE
Alex Kelly046d6622012-10-04 17:15:23 -07001335 depends on COREDUMP
Matt Mackall708e9a72006-01-08 01:05:25 -08001336 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001337 bool "Enable ELF core dumps" if EXPERT
Matt Mackall708e9a72006-01-08 01:05:25 -08001338 help
1339 Enable support for generating core dumps. Disabling saves about 4k.
1340
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001341
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +02001342config PCSPKR_PLATFORM
David Rientjes6a108a12011-01-20 14:44:16 -08001343 bool "Enable PC-Speaker support" if EXPERT
Ralf Baechle8761f1a2011-06-01 19:05:09 +01001344 depends on HAVE_PCSPKR_PLATFORM
Ralf Baechle15f304b2011-06-01 19:04:59 +01001345 select I8253_LOCK
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +02001346 default y
1347 help
1348 This option allows to disable the internal PC-Speaker
1349 support, saving some memory.
1350
Linus Torvalds1da177e2005-04-16 15:20:36 -07001351config BASE_FULL
1352 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001353 bool "Enable full-sized data structures for core" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001354 help
1355 Disabling this option reduces the size of miscellaneous core
1356 kernel data structures. This saves memory on small machines,
1357 but may reduce performance.
1358
1359config FUTEX
David Rientjes6a108a12011-01-20 14:44:16 -08001360 bool "Enable futex support" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001361 default y
Ingo Molnar23f78d4a2006-06-27 02:54:53 -07001362 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001363 help
1364 Disabling this option will cause the kernel to be built without
1365 support for "fast userspace mutexes". The resulting kernel may not
1366 run glibc-based applications correctly.
1367
1368config EPOLL
David Rientjes6a108a12011-01-20 14:44:16 -08001369 bool "Enable eventpoll support" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370 default y
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001371 select ANON_INODES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001372 help
1373 Disabling this option will cause the kernel to be built without
1374 support for epoll family of system calls.
1375
Davide Libenzifba2afa2007-05-10 22:23:13 -07001376config SIGNALFD
David Rientjes6a108a12011-01-20 14:44:16 -08001377 bool "Enable signalfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001378 select ANON_INODES
Davide Libenzifba2afa2007-05-10 22:23:13 -07001379 default y
1380 help
1381 Enable the signalfd() system call that allows to receive signals
1382 on a file descriptor.
1383
1384 If unsure, say Y.
1385
Davide Libenzib215e282007-05-10 22:23:16 -07001386config TIMERFD
David Rientjes6a108a12011-01-20 14:44:16 -08001387 bool "Enable timerfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001388 select ANON_INODES
Davide Libenzib215e282007-05-10 22:23:16 -07001389 default y
1390 help
1391 Enable the timerfd() system call that allows to receive timer
1392 events on a file descriptor.
1393
1394 If unsure, say Y.
1395
Davide Libenzie1ad7462007-05-10 22:23:19 -07001396config EVENTFD
David Rientjes6a108a12011-01-20 14:44:16 -08001397 bool "Enable eventfd() system call" if EXPERT
Adrian Bunk448e3ce2007-07-31 00:39:10 -07001398 select ANON_INODES
Davide Libenzie1ad7462007-05-10 22:23:19 -07001399 default y
1400 help
1401 Enable the eventfd() system call that allows to receive both
1402 kernel notification (ie. KAIO) or userspace notifications.
1403
1404 If unsure, say Y.
1405
Linus Torvalds1da177e2005-04-16 15:20:36 -07001406config SHMEM
David Rientjes6a108a12011-01-20 14:44:16 -08001407 bool "Use full shmem filesystem" if EXPERT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001408 default y
1409 depends on MMU
1410 help
1411 The shmem is an internal filesystem used to manage shared memory.
1412 It is backed by swap and manages resource limits. It is also exported
1413 to userspace as tmpfs if TMPFS is enabled. Disabling this
1414 option replaces shmem and tmpfs with the much simpler ramfs code,
1415 which may be appropriate on small systems without swap.
1416
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001417config AIO
David Rientjes6a108a12011-01-20 14:44:16 -08001418 bool "Enable AIO support" if EXPERT
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001419 default y
1420 help
1421 This option enables POSIX asynchronous I/O which may by used
Mike Frysinger657a5202013-04-30 15:28:45 -07001422 by some high performance threaded applications. Disabling
1423 this option saves about 7k.
1424
1425config PCI_QUIRKS
1426 default y
1427 bool "Enable PCI quirk workarounds" if EXPERT
1428 depends on PCI
1429 help
1430 This enables workarounds for various PCI chipset
1431 bugs/quirks. Disable this only if your target machine is
1432 unaffected by PCI quirks.
Thomas Petazzoniebf3f092008-10-15 22:05:12 -07001433
Randy Dunlap6befe5f2011-04-26 12:33:21 -07001434config EMBEDDED
1435 bool "Embedded system"
1436 select EXPERT
1437 help
1438 This option should be enabled if compiling the kernel for
1439 an embedded system so certain expert options are available
1440 for configuration.
1441
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001442config HAVE_PERF_EVENTS
Thomas Gleixner0793a612008-12-04 20:12:29 +01001443 bool
Mike Frysinger018df722009-06-12 13:17:43 -04001444 help
1445 See tools/perf/design.txt for details.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001446
Peter Zijlstra906010b2009-09-21 16:08:49 +02001447config PERF_USE_VMALLOC
1448 bool
1449 help
1450 See tools/perf/design.txt for details
1451
Ingo Molnar57c0c152009-09-21 12:20:38 +02001452menu "Kernel Performance Events And Counters"
Thomas Gleixner0793a612008-12-04 20:12:29 +01001453
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001454config PERF_EVENTS
Ingo Molnar57c0c152009-09-21 12:20:38 +02001455 bool "Kernel performance events and counters"
Robert Richter392d65a2012-04-05 18:24:44 +02001456 default y if PROFILING
Ingo Molnarcdd6c482009-09-21 12:02:48 +02001457 depends on HAVE_PERF_EVENTS
Ingo Molnar4c59e462008-12-08 19:38:33 +01001458 select ANON_INODES
Peter Zijlstrae360adb2010-10-14 14:01:34 +08001459 select IRQ_WORK
Thomas Gleixner0793a612008-12-04 20:12:29 +01001460 help
Ingo Molnar57c0c152009-09-21 12:20:38 +02001461 Enable kernel support for various performance events provided
1462 by software and hardware.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001463
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001464 Software events are supported either built-in or via the
Ingo Molnar57c0c152009-09-21 12:20:38 +02001465 use of generic tracepoints.
1466
1467 Most modern CPUs support performance events via performance
1468 counter registers. These registers count the number of certain
Thomas Gleixner0793a612008-12-04 20:12:29 +01001469 types of hw events: such as instructions executed, cachemisses
1470 suffered, or branches mis-predicted - without slowing down the
1471 kernel or applications. These registers can also trigger interrupts
1472 when a threshold number of events have passed - and can thus be
1473 used to profile the code that runs on that CPU.
1474
Ingo Molnar57c0c152009-09-21 12:20:38 +02001475 The Linux Performance Event subsystem provides an abstraction of
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001476 these software and hardware event capabilities, available via a
Ingo Molnar57c0c152009-09-21 12:20:38 +02001477 system call and used by the "perf" utility in tools/perf/. It
Thomas Gleixner0793a612008-12-04 20:12:29 +01001478 provides per task and per CPU counters, and it provides event
1479 capabilities on top of those.
1480
1481 Say Y if unsure.
1482
Peter Zijlstra906010b2009-09-21 16:08:49 +02001483config DEBUG_PERF_USE_VMALLOC
1484 default n
1485 bool "Debug: use vmalloc to back perf mmap() buffers"
1486 depends on PERF_EVENTS && DEBUG_KERNEL
1487 select PERF_USE_VMALLOC
1488 help
1489 Use vmalloc memory to back perf mmap() buffers.
1490
1491 Mostly useful for debugging the vmalloc code on platforms
1492 that don't require it.
1493
1494 Say N if unsure.
1495
Thomas Gleixner0793a612008-12-04 20:12:29 +01001496endmenu
1497
Christoph Lameterf8891e52006-06-30 01:55:45 -07001498config VM_EVENT_COUNTERS
1499 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001500 bool "Enable VM event counters for /proc/vmstat" if EXPERT
Christoph Lameterf8891e52006-06-30 01:55:45 -07001501 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001502 VM event counters are needed for event counts to be shown.
1503 This option allows the disabling of the VM event counters
David Rientjes6a108a12011-01-20 14:44:16 -08001504 on EXPERT systems. /proc/vmstat will only show page counts
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001505 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -07001506
Christoph Lameter41ecc552007-05-09 02:32:44 -07001507config SLUB_DEBUG
1508 default y
David Rientjes6a108a12011-01-20 14:44:16 -08001509 bool "Enable SLUB debugging support" if EXPERT
Christoph Lameterf6acb632008-04-29 16:16:06 -07001510 depends on SLUB && SYSFS
Christoph Lameter41ecc552007-05-09 02:32:44 -07001511 help
1512 SLUB has extensive debug support features. Disabling these can
1513 result in significant savings in code size. This also disables
1514 SLUB sysfs support. /sys/slab will not exist and there will be
1515 no support for cache validation etc.
1516
Randy Dunlapb943c462009-03-10 12:55:46 -07001517config COMPAT_BRK
1518 bool "Disable heap randomization"
1519 default y
1520 help
1521 Randomizing heap placement makes heap exploits harder, but it
1522 also breaks ancient binaries (including anything libc5 based).
1523 This option changes the bootup default to heap randomization
Matt LaPlante692105b2009-01-26 11:12:25 +01001524 disabled, and can be overridden at runtime by setting
Randy Dunlapb943c462009-03-10 12:55:46 -07001525 /proc/sys/kernel/randomize_va_space to 2.
1526
1527 On non-ancient distros (post-2000 ones) N is usually a safe choice.
1528
Christoph Lameter81819f02007-05-06 14:49:36 -07001529choice
1530 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -07001531 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001532 help
1533 This option allows to select a slab allocator.
1534
1535config SLAB
1536 bool "SLAB"
1537 help
1538 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -07001539 well in all environments. It organizes cache hot objects in
Simon Arlott02f56212008-11-05 22:18:19 +00001540 per cpu and per node queues.
Christoph Lameter81819f02007-05-06 14:49:36 -07001541
1542config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001543 bool "SLUB (Unqueued Allocator)"
1544 help
1545 SLUB is a slab allocator that minimizes cache line usage
1546 instead of managing queues of cached objects (SLAB approach).
1547 Per cpu caching is realized using slabs of objects instead
1548 of queues of objects. SLUB can use memory efficiently
Simon Arlott02f56212008-11-05 22:18:19 +00001549 and has enhanced diagnostics. SLUB is the default choice for
1550 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -07001551
1552config SLOB
David Rientjes6a108a12011-01-20 14:44:16 -08001553 depends on EXPERT
Christoph Lameter81819f02007-05-06 14:49:36 -07001554 bool "SLOB (Simple Allocator)"
1555 help
Matt Mackall37291452008-02-04 22:29:38 -08001556 SLOB replaces the stock allocator with a drastically simpler
1557 allocator. SLOB is generally more space efficient but
1558 does not perform as well on large systems.
Christoph Lameter81819f02007-05-06 14:49:36 -07001559
1560endchoice
1561
Jie Zhangea637632009-12-14 18:00:02 -08001562config MMAP_ALLOW_UNINITIALIZED
1563 bool "Allow mmapped anonymous memory to be uninitialized"
David Rientjes6a108a12011-01-20 14:44:16 -08001564 depends on EXPERT && !MMU
Jie Zhangea637632009-12-14 18:00:02 -08001565 default n
1566 help
1567 Normally, and according to the Linux spec, anonymous memory obtained
1568 from mmap() has it's contents cleared before it is passed to
1569 userspace. Enabling this config option allows you to request that
1570 mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus
1571 providing a huge performance boost. If this option is not enabled,
1572 then the flag will be ignored.
1573
1574 This is taken advantage of by uClibc's malloc(), and also by
1575 ELF-FDPIC binfmt's brk and stack allocator.
1576
1577 Because of the obvious security issues, this option should only be
1578 enabled on embedded devices where you control what is run in
1579 userspace. Since that isn't generally a problem on no-MMU systems,
1580 it is normally safe to say Y here.
1581
1582 See Documentation/nommu-mmap.txt for more information.
1583
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001584config PROFILING
Robert Richterb309a292010-02-26 15:01:23 +01001585 bool "Profiling support"
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001586 help
1587 Say Y here to enable the extended profiling support mechanisms used
1588 by profilers such as OProfile.
1589
Ingo Molnar5f87f112008-07-23 14:15:22 +02001590#
1591# Place an empty function call at each tracepoint site. Can be
1592# dynamically changed for a probe function.
1593#
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001594config TRACEPOINTS
Ingo Molnar5f87f112008-07-23 14:15:22 +02001595 bool
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001596
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -05001597source "arch/Kconfig"
1598
Linus Torvalds1da177e2005-04-16 15:20:36 -07001599endmenu # General setup
1600
Dmitry Baryshkovee7e5512008-06-29 14:18:46 +04001601config HAVE_GENERIC_DMA_COHERENT
1602 bool
1603 default n
1604
Linus Torvalds158a9622008-01-02 13:04:48 -08001605config SLABINFO
1606 bool
1607 depends on PROC_FS
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001608 depends on SLAB || SLUB_DEBUG
Linus Torvalds158a9622008-01-02 13:04:48 -08001609 default y
1610
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001611config RT_MUTEXES
1612 boolean
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001613
Linus Torvalds1da177e2005-04-16 15:20:36 -07001614config BASE_SMALL
1615 int
1616 default 0 if BASE_FULL
1617 default 1 if !BASE_FULL
1618
Jan Engelhardt66da5732007-07-15 23:39:29 -07001619menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001620 bool "Enable loadable module support"
1621 help
1622 Kernel modules are small pieces of compiled code which can
1623 be inserted in the running kernel, rather than being
1624 permanently built into the kernel. You use the "modprobe"
1625 tool to add (and sometimes remove) them. If you say Y here,
1626 many parts of the kernel can be built as modules (by
1627 answering M instead of Y where indicated): this is most
1628 useful for infrequently used options which are not required
1629 for booting. For more information, see the man pages for
1630 modprobe, lsmod, modinfo, insmod and rmmod.
1631
1632 If you say Y here, you will need to run "make
1633 modules_install" to put the modules under /lib/modules/
1634 where modprobe can find them (you may need to be root to do
1635 this).
1636
1637 If unsure, say Y.
1638
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001639if MODULES
1640
Linus Torvalds826e4502008-05-04 17:04:16 -07001641config MODULE_FORCE_LOAD
1642 bool "Forced module loading"
Linus Torvalds826e4502008-05-04 17:04:16 -07001643 default n
1644 help
Rusty Russell91e37a72008-05-09 16:25:28 +10001645 Allow loading of modules without version information (ie. modprobe
1646 --force). Forced module loading sets the 'F' (forced) taint flag and
1647 is usually a really bad idea.
Linus Torvalds826e4502008-05-04 17:04:16 -07001648
Linus Torvalds1da177e2005-04-16 15:20:36 -07001649config MODULE_UNLOAD
1650 bool "Module unloading"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001651 help
1652 Without this option you will not be able to unload any
1653 modules (note that some modules may not be unloadable
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001654 anyway), which makes your kernel smaller, faster
1655 and simpler. If unsure, say Y.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001656
1657config MODULE_FORCE_UNLOAD
1658 bool "Forced module unloading"
Kees Cook19c92392012-10-02 11:19:29 -07001659 depends on MODULE_UNLOAD
Linus Torvalds1da177e2005-04-16 15:20:36 -07001660 help
1661 This option allows you to force a module to unload, even if the
1662 kernel believes it is unsafe: the kernel will remove the module
1663 without waiting for anyone to stop using it (using the -f option to
1664 rmmod). This is mainly for kernel developers and desperate users.
1665 If unsure, say N.
1666
Linus Torvalds1da177e2005-04-16 15:20:36 -07001667config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +01001668 bool "Module versioning support"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669 help
1670 Usually, you have to use modules compiled with your kernel.
1671 Saying Y here makes it sometimes possible to use modules
1672 compiled for different kernels, by adding enough information
1673 to the modules to (hopefully) spot any changes which would
1674 make them incompatible with the kernel you are running. If
1675 unsure, say N.
1676
1677config MODULE_SRCVERSION_ALL
1678 bool "Source checksum for all modules"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001679 help
1680 Modules which contain a MODULE_VERSION get an extra "srcversion"
1681 field inserted into their modinfo section, which contains a
1682 sum of the source files which made it. This helps maintainers
1683 see exactly which source was used to build a module (since
1684 others sometimes change the module source without updating
1685 the version). With this option, such a "srcversion" field
1686 will be created for all modules. If unsure, say N.
1687
Rusty Russell106a4ee2012-09-26 10:09:40 +01001688config MODULE_SIG
1689 bool "Module signature verification"
1690 depends on MODULES
David Howells48ba2462012-09-26 10:11:03 +01001691 select KEYS
1692 select CRYPTO
1693 select ASYMMETRIC_KEY_TYPE
1694 select ASYMMETRIC_PUBLIC_KEY_SUBTYPE
1695 select PUBLIC_KEY_ALGO_RSA
1696 select ASN1
1697 select OID_REGISTRY
1698 select X509_CERTIFICATE_PARSER
Rusty Russell106a4ee2012-09-26 10:09:40 +01001699 help
1700 Check modules for valid signatures upon load: the signature
1701 is simply appended to the module. For more information see
1702 Documentation/module-signing.txt.
1703
David Howellsea0b6dc2012-09-26 10:09:50 +01001704 !!!WARNING!!! If you enable this option, you MUST make sure that the
1705 module DOES NOT get stripped after being signed. This includes the
1706 debuginfo strip done by some packagers (such as rpmbuild) and
1707 inclusion into an initramfs that wants the module size reduced.
1708
Rusty Russell106a4ee2012-09-26 10:09:40 +01001709config MODULE_SIG_FORCE
1710 bool "Require modules to be validly signed"
1711 depends on MODULE_SIG
1712 help
1713 Reject unsigned modules or signed modules for which we don't have a
1714 key. Without this, such modules will simply taint the kernel.
David Howellsea0b6dc2012-09-26 10:09:50 +01001715
Michal Marekd9d8d7e2013-01-25 13:41:31 +10301716config MODULE_SIG_ALL
1717 bool "Automatically sign all modules"
1718 default y
1719 depends on MODULE_SIG
1720 help
1721 Sign all modules during make modules_install. Without this option,
1722 modules must be signed manually, using the scripts/sign-file tool.
1723
1724comment "Do not forget to sign required modules with scripts/sign-file"
1725 depends on MODULE_SIG_FORCE && !MODULE_SIG_ALL
1726
David Howellsea0b6dc2012-09-26 10:09:50 +01001727choice
1728 prompt "Which hash algorithm should modules be signed with?"
1729 depends on MODULE_SIG
1730 help
1731 This determines which sort of hashing algorithm will be used during
1732 signature generation. This algorithm _must_ be built into the kernel
1733 directly so that signature verification can take place. It is not
1734 possible to load a signed module containing the algorithm to check
1735 the signature on that module.
1736
1737config MODULE_SIG_SHA1
1738 bool "Sign modules with SHA-1"
1739 select CRYPTO_SHA1
1740
1741config MODULE_SIG_SHA224
1742 bool "Sign modules with SHA-224"
1743 select CRYPTO_SHA256
1744
1745config MODULE_SIG_SHA256
1746 bool "Sign modules with SHA-256"
1747 select CRYPTO_SHA256
1748
1749config MODULE_SIG_SHA384
1750 bool "Sign modules with SHA-384"
1751 select CRYPTO_SHA512
1752
1753config MODULE_SIG_SHA512
1754 bool "Sign modules with SHA-512"
1755 select CRYPTO_SHA512
1756
1757endchoice
1758
Michal Marek22753672013-01-25 13:41:00 +10301759config MODULE_SIG_HASH
1760 string
1761 depends on MODULE_SIG
1762 default "sha1" if MODULE_SIG_SHA1
1763 default "sha224" if MODULE_SIG_SHA224
1764 default "sha256" if MODULE_SIG_SHA256
1765 default "sha384" if MODULE_SIG_SHA384
1766 default "sha512" if MODULE_SIG_SHA512
1767
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001768endif # MODULES
1769
Rusty Russell98a79d62008-12-13 21:19:41 +10301770config INIT_ALL_POSSIBLE
1771 bool
1772 help
Rusty Russell5f054e32012-03-29 15:38:31 +10301773 Back when each arch used to define their own cpu_online_mask and
1774 cpu_possible_mask, some of them chose to initialize cpu_possible_mask
Rusty Russell98a79d62008-12-13 21:19:41 +10301775 with all 1s, and others with all 0s. When they were centralised,
1776 it was better to provide this option than to break all the archs
Matt LaPlante692105b2009-01-26 11:12:25 +01001777 and have several arch maintainers pursuing me down dark alleys.
Rusty Russell98a79d62008-12-13 21:19:41 +10301778
Linus Torvalds1da177e2005-04-16 15:20:36 -07001779config STOP_MACHINE
1780 bool
1781 default y
1782 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
1783 help
1784 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001785
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001786source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -07001787
1788config PREEMPT_NOTIFIERS
1789 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +01001790
Steffen Klassert16295be2010-01-06 19:47:10 +11001791config PADATA
1792 depends on SMP
1793 bool
1794
Andi Kleen754b7b62012-10-04 17:11:27 -07001795# Can be selected by architectures with broken toolchains
1796# that get confused by correct const<->read_only section
1797# mappings
1798config BROKEN_RODATA
1799 bool
1800
David Howells4520c6a2012-09-21 23:31:13 +01001801config ASN1
1802 tristate
1803 help
1804 Build a simple ASN.1 grammar compiler that produces a bytecode output
1805 that can be interpreted by the ASN.1 stream decoder and used to
1806 inform it as to what tags are to be expected in a stream and what
1807 functions to call on what tags.
1808
Thomas Gleixner6beb0002009-11-09 15:21:34 +00001809source "kernel/Kconfig.locks"