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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 Oberparleiterb99b87f72009-06-17 16:28:03 -070019config CONSTRUCTORS
20 bool
21 depends on !UML
22 default y
23
Peter Zijlstrae360adb2010-10-14 14:01:34 +080024config HAVE_IRQ_WORK
25 bool
26
27config IRQ_WORK
28 bool
29 depends on HAVE_IRQ_WORK
30
Al Boldiff0cfc62007-07-31 00:39:23 -070031menu "General setup"
Linus Torvalds1da177e2005-04-16 15:20:36 -070032
33config EXPERIMENTAL
34 bool "Prompt for development and/or incomplete code/drivers"
35 ---help---
36 Some of the various things that Linux supports (such as network
37 drivers, file systems, network protocols, etc.) can be in a state
38 of development where the functionality, stability, or the level of
39 testing is not yet high enough for general use. This is usually
40 known as the "alpha-test" phase among developers. If a feature is
41 currently in alpha-test, then the developers usually discourage
42 uninformed widespread use of this feature by the general public to
43 avoid "Why doesn't this work?" type mail messages. However, active
44 testing and use of these systems is welcomed. Just be aware that it
45 may not meet the normal level of reliability or it may fail to work
46 in some special cases. Detailed bug reports from people familiar
47 with the kernel internals are usually welcomed by the developers
48 (before submitting bug reports, please read the documents
49 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
50 <file:Documentation/BUG-HUNTING>, and
51 <file:Documentation/oops-tracing.txt> in the kernel source).
52
53 This option will also make obsoleted drivers available. These are
54 drivers that have been replaced by something else, and/or are
55 scheduled to be removed in a future kernel release.
56
57 Unless you intend to help test and develop a feature or driver that
58 falls into this category, or you have a situation that requires
59 using these features, you should probably say N here, which will
60 cause the configurator to present you with fewer choices. If
61 you say Y here, you will be offered the choice of using features or
62 drivers that are currently considered to be in the alpha-test phase.
63
Linus Torvalds1da177e2005-04-16 15:20:36 -070064config BROKEN
65 bool
Linus Torvalds1da177e2005-04-16 15:20:36 -070066
67config BROKEN_ON_SMP
68 bool
69 depends on BROKEN || !SMP
70 default y
71
72config LOCK_KERNEL
73 bool
74 depends on SMP || PREEMPT
75 default y
76
77config INIT_ENV_ARG_LIMIT
78 int
Adrian Bunkdd673bc2006-06-30 01:55:51 -070079 default 32 if !UML
80 default 128 if UML
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 help
Randy Dunlap34ad92c22005-10-30 15:01:46 -080082 Maximum of each of the number of arguments and environment
83 variables passed to init from the kernel command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -070084
Linus Torvalds1da177e2005-04-16 15:20:36 -070085
Roland McGrath84336462009-12-21 16:24:06 -080086config CROSS_COMPILE
87 string "Cross-compiler tool prefix"
88 help
89 Same as running 'make CROSS_COMPILE=prefix-' but stored for
90 default make runs in this kernel build directory. You don't
91 need to set this unless you want the configured kernel build
92 directory to select the cross-compiler automatically.
93
Linus Torvalds1da177e2005-04-16 15:20:36 -070094config LOCALVERSION
95 string "Local version - append to kernel release"
96 help
97 Append an extra string to the end of your kernel version.
98 This will show up when you type uname, for example.
99 The string you set here will be appended after the contents of
100 any files with a filename matching localversion* in your
101 object and source tree, in that order. Your total string can
102 be a maximum of 64 characters.
103
Ryan Andersonaaebf432005-07-31 04:57:49 -0400104config LOCALVERSION_AUTO
105 bool "Automatically append version information to the version string"
106 default y
107 help
108 This will try to automatically determine if the current tree is a
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200109 release tree by looking for git tags that belong to the current
110 top of tree revision.
Ryan Andersonaaebf432005-07-31 04:57:49 -0400111
112 A string of the format -gxxxxxxxx will be added to the localversion
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200113 if a git-based tree is found. The string generated by this will be
Ryan Andersonaaebf432005-07-31 04:57:49 -0400114 appended after any matching localversion* files, and after the value
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200115 set in CONFIG_LOCALVERSION.
Ryan Andersonaaebf432005-07-31 04:57:49 -0400116
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200117 (The actual string used here is the first eight characters produced
118 by running the command:
119
120 $ git rev-parse --verify HEAD
121
122 which is done within the script "scripts/setlocalversion".)
Ryan Andersonaaebf432005-07-31 04:57:49 -0400123
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800124config HAVE_KERNEL_GZIP
125 bool
126
127config HAVE_KERNEL_BZIP2
128 bool
129
130config HAVE_KERNEL_LZMA
131 bool
132
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800133config HAVE_KERNEL_LZO
134 bool
135
Alain Knaff30d65db2009-01-04 22:46:17 +0100136choice
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800137 prompt "Kernel compression mode"
138 default KERNEL_GZIP
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800139 depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_LZO
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800140 help
Alain Knaff30d65db2009-01-04 22:46:17 +0100141 The linux kernel is a kind of self-extracting executable.
142 Several compression algorithms are available, which differ
143 in efficiency, compression and decompression speed.
144 Compression speed is only relevant when building a kernel.
145 Decompression speed is relevant at each boot.
146
147 If you have any problems with bzip2 or lzma compressed
148 kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
149 version of this functionality (bzip2 only), for 2.4, was
150 supplied by Christian Ludwig)
151
152 High compression options are mostly useful for users, who
153 are low on disk space (embedded systems), but for whom ram
154 size matters less.
155
156 If in doubt, select 'gzip'
157
158config KERNEL_GZIP
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800159 bool "Gzip"
160 depends on HAVE_KERNEL_GZIP
161 help
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800162 The old and tried gzip compression. It provides a good balance
163 between compression ratio and decompression speed.
Alain Knaff30d65db2009-01-04 22:46:17 +0100164
165config KERNEL_BZIP2
166 bool "Bzip2"
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800167 depends on HAVE_KERNEL_BZIP2
Alain Knaff30d65db2009-01-04 22:46:17 +0100168 help
169 Its compression ratio and speed is intermediate.
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800170 Decompression speed is slowest among the three. The kernel
171 size is about 10% smaller with bzip2, in comparison to gzip.
172 Bzip2 uses a large amount of memory. For modern kernels you
173 will need at least 8MB RAM or more for booting.
Alain Knaff30d65db2009-01-04 22:46:17 +0100174
175config KERNEL_LZMA
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800176 bool "LZMA"
177 depends on HAVE_KERNEL_LZMA
178 help
179 The most recent compression algorithm.
180 Its ratio is best, decompression speed is between the other
181 two. Compression is slowest. The kernel size is about 33%
182 smaller with LZMA in comparison to gzip.
Alain Knaff30d65db2009-01-04 22:46:17 +0100183
Albin Tonnerre7dd65fe2010-01-08 14:42:42 -0800184config KERNEL_LZO
185 bool "LZO"
186 depends on HAVE_KERNEL_LZO
187 help
188 Its compression ratio is the poorest among the 4. The kernel
189 size is about about 10% bigger than gzip; however its speed
190 (both compression and decompression) is the fastest.
191
Alain Knaff30d65db2009-01-04 22:46:17 +0100192endchoice
193
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194config SWAP
195 bool "Support for paging of anonymous memory (swap)"
David Howells93614012006-09-30 20:45:40 +0200196 depends on MMU && BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197 default y
198 help
199 This option allows you to choose whether you want to have support
Jesper Juhl92c35042006-01-15 02:40:08 +0100200 for so called swap devices or swap files in your kernel that are
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 used to provide more virtual memory than the actual RAM present
202 in your computer. If unsure say Y.
203
204config SYSVIPC
205 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206 ---help---
207 Inter Process Communication is a suite of library functions and
208 system calls which let processes (running programs) synchronize and
209 exchange information. It is generally considered to be a good thing,
210 and some programs won't run unless you say Y here. In particular, if
211 you want to run the DOS emulator dosemu under Linux (read the
212 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
213 you'll need to say Y here.
214
215 You can find documentation about IPC with "info ipc" and also in
216 section 6.4 of the Linux Programmer's Guide, available from
217 <http://www.tldp.org/guides.html>.
218
Eric W. Biedermana5494dc2007-02-14 00:34:06 -0800219config SYSVIPC_SYSCTL
220 bool
221 depends on SYSVIPC
222 depends on SYSCTL
223 default y
224
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225config POSIX_MQUEUE
226 bool "POSIX Message Queues"
227 depends on NET && EXPERIMENTAL
228 ---help---
229 POSIX variant of message queues is a part of IPC. In POSIX message
230 queues every message has a priority which decides about succession
231 of receiving it by a process. If you want to compile and run
232 programs written e.g. for Solaris with use of its POSIX message
Robert P. J. Dayb0e37652007-05-09 07:25:13 +0200233 queues (functions mq_*) say Y here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234
235 POSIX message queues are visible as a filesystem called 'mqueue'
236 and can be mounted somewhere if you want to do filesystem
237 operations on message queues.
238
239 If unsure, say Y.
240
Serge E. Hallynbdc8e5f2009-04-06 19:01:11 -0700241config POSIX_MQUEUE_SYSCTL
242 bool
243 depends on POSIX_MQUEUE
244 depends on SYSCTL
245 default y
246
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247config BSD_PROCESS_ACCT
248 bool "BSD Process Accounting"
249 help
250 If you say Y here, a user level program will be able to instruct the
251 kernel (via a special system call) to write process accounting
252 information to a file: whenever a process exits, information about
253 that process will be appended to the file by the kernel. The
254 information includes things such as creation time, owning user,
255 command name, memory usage, controlling terminal etc. (the complete
256 list is in the struct acct in <file:include/linux/acct.h>). It is
257 up to the user level program to do useful things with this
258 information. This is generally a good idea, so say Y.
259
260config BSD_PROCESS_ACCT_V3
261 bool "BSD Process Accounting version 3 file format"
262 depends on BSD_PROCESS_ACCT
263 default n
264 help
265 If you say Y here, the process accounting information is written
266 in a new file format that also logs the process IDs of each
267 process and it's parent. Note that this file format is incompatible
268 with previous v0/v1/v2 file formats, so you will need updated tools
269 for processing it. A preliminary version of these tools is available
S.Çağlar Onur37a4c942008-06-18 11:45:13 +0300270 at <http://www.gnu.org/software/acct/>.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271
Shailabh Nagarc7572492006-07-14 00:24:40 -0700272config TASKSTATS
273 bool "Export task/process statistics through netlink (EXPERIMENTAL)"
274 depends on NET
275 default n
276 help
277 Export selected statistics for tasks/processes through the
278 generic netlink interface. Unlike BSD process accounting, the
279 statistics are available during the lifetime of tasks/processes as
280 responses to commands. Like BSD accounting, they are sent to user
281 space on task exit.
282
283 Say N if unsure.
284
Shailabh Nagarca74e922006-07-14 00:24:36 -0700285config TASK_DELAY_ACCT
286 bool "Enable per-task delay accounting (EXPERIMENTAL)"
Shailabh Nagar6f449932006-07-14 00:24:41 -0700287 depends on TASKSTATS
Shailabh Nagarca74e922006-07-14 00:24:36 -0700288 help
289 Collect information on time spent by a task waiting for system
290 resources like cpu, synchronous block I/O completion and swapping
291 in pages. Such statistics can help in setting a task's priorities
292 relative to other tasks for cpu, io, rss limits etc.
293
294 Say N if unsure.
295
Alexey Dobriyan18f705f2007-02-10 01:46:44 -0800296config TASK_XACCT
297 bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
298 depends on TASKSTATS
299 help
300 Collect extended task accounting data and send the data
301 to userland for processing over the taskstats interface.
302
303 Say N if unsure.
304
305config TASK_IO_ACCOUNTING
306 bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
307 depends on TASK_XACCT
308 help
309 Collect information on the number of bytes of storage I/O which this
310 task has caused.
311
312 Say N if unsure.
313
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314config AUDIT
315 bool "Auditing support"
Chris Wright804a6a492005-05-11 10:52:45 +0100316 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 help
318 Enable auditing infrastructure that can be used with another
319 kernel subsystem, such as SELinux (which requires this for
320 logging of avc messages output). Does not do system-call
321 auditing without CONFIG_AUDITSYSCALL.
322
323config AUDITSYSCALL
324 bool "Enable system-call auditing support"
Kumar Gala022382a2009-10-16 07:21:37 +0000325 depends on AUDIT && (X86 || PPC || S390 || IA64 || UML || SPARC64 || SUPERH)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326 default y if SECURITY_SELINUX
327 help
328 Enable low-overhead system-call auditing infrastructure that
329 can be used independently or with another kernel subsystem,
Eric Paris67640b62009-12-17 20:12:06 -0500330 such as SELinux.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331
Eric Paris939a67f2009-12-17 20:12:06 -0500332config AUDIT_WATCH
333 def_bool y
334 depends on AUDITSYSCALL
335 select FSNOTIFY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336
Al Viro74c3cbe2007-07-22 08:04:18 -0400337config AUDIT_TREE
338 def_bool y
Eric Paris63c882a2009-05-21 17:02:01 -0400339 depends on AUDITSYSCALL
Eric Paris28a3a7e2009-12-17 20:12:05 -0500340 select FSNOTIFY
Al Viro74c3cbe2007-07-22 08:04:18 -0400341
Mike Travisc903ff82009-01-15 12:28:29 -0800342menu "RCU Subsystem"
343
344choice
345 prompt "RCU Implementation"
Paul E. McKenney31c9a242009-04-02 21:06:25 -0700346 default TREE_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800347
Mike Travisc903ff82009-01-15 12:28:29 -0800348config TREE_RCU
349 bool "Tree-based hierarchical RCU"
350 help
351 This option selects the RCU implementation that is
352 designed for very large SMP system with hundreds or
Paul E. McKenneyc17ef452009-06-23 17:12:47 -0700353 thousands of CPUs. It also scales down nicely to
354 smaller systems.
Mike Travisc903ff82009-01-15 12:28:29 -0800355
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700356config TREE_PREEMPT_RCU
357 bool "Preemptable tree-based hierarchical RCU"
358 depends on PREEMPT
359 help
360 This option selects the RCU implementation that is
361 designed for very large SMP systems with hundreds or
362 thousands of CPUs, but for which real-time response
Paul E. McKenneybbe3eae2009-09-13 09:15:08 -0700363 is also required. It also scales down nicely to
364 smaller systems.
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700365
Paul E. McKenney9b1d82f2009-10-25 19:03:50 -0700366config TINY_RCU
367 bool "UP-only small-memory-footprint RCU"
368 depends on !SMP
369 help
370 This option selects the RCU implementation that is
371 designed for UP systems from which real-time response
372 is not required. This option greatly reduces the
373 memory footprint of RCU.
374
Mike Travisc903ff82009-01-15 12:28:29 -0800375endchoice
376
377config RCU_TRACE
378 bool "Enable tracing for RCU"
Paul E. McKenney6b3ef482009-08-22 13:56:53 -0700379 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800380 help
381 This option provides tracing in RCU which presents stats
382 in debugfs for debugging RCU implementation.
383
384 Say Y here if you want to enable RCU tracing
385 Say N if you are unsure.
386
387config RCU_FANOUT
388 int "Tree-based hierarchical RCU fanout value"
389 range 2 64 if 64BIT
390 range 2 32 if !64BIT
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700391 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800392 default 64 if 64BIT
393 default 32 if !64BIT
394 help
395 This option controls the fanout of hierarchical implementations
396 of RCU, allowing RCU to work efficiently on machines with
397 large numbers of CPUs. This value must be at least the cube
398 root of NR_CPUS, which allows NR_CPUS up to 32,768 for 32-bit
399 systems and up to 262,144 for 64-bit systems.
400
401 Select a specific number if testing RCU itself.
402 Take the default if unsure.
403
404config RCU_FANOUT_EXACT
405 bool "Disable tree-based hierarchical RCU auto-balancing"
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700406 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800407 default n
408 help
409 This option forces use of the exact RCU_FANOUT value specified,
410 regardless of imbalances in the hierarchy. This is useful for
411 testing RCU itself, and might one day be useful on systems with
412 strong NUMA behavior.
413
414 Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
415
416 Say N if unsure.
417
Paul E. McKenney8bd93a22010-02-22 17:04:59 -0800418config RCU_FAST_NO_HZ
419 bool "Accelerate last non-dyntick-idle CPU's grace periods"
420 depends on TREE_RCU && NO_HZ && SMP
421 default n
422 help
423 This option causes RCU to attempt to accelerate grace periods
424 in order to allow the final CPU to enter dynticks-idle state
425 more quickly. On the other hand, this option increases the
426 overhead of the dynticks-idle checking, particularly on systems
427 with large numbers of CPUs.
428
429 Say Y if energy efficiency is critically important, particularly
430 if you have relatively few CPUs.
431
432 Say N if you are unsure.
433
Mike Travisc903ff82009-01-15 12:28:29 -0800434config TREE_RCU_TRACE
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700435 def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
Mike Travisc903ff82009-01-15 12:28:29 -0800436 select DEBUG_FS
437 help
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700438 This option provides tracing for the TREE_RCU and
439 TREE_PREEMPT_RCU implementations, permitting Makefile to
440 trivially select kernel/rcutree_trace.c.
Mike Travisc903ff82009-01-15 12:28:29 -0800441
Mike Travisc903ff82009-01-15 12:28:29 -0800442endmenu # "RCU Subsystem"
443
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700445 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 ---help---
447 This option enables the complete Linux kernel ".config" file
448 contents to be saved in the kernel. It provides documentation
449 of which kernel options are used in a running kernel or in an
450 on-disk kernel. This information can be extracted from the kernel
451 image file with the script scripts/extract-ikconfig and used as
452 input to rebuild the current kernel or to build another kernel.
453 It can also be extracted from a running kernel by reading
454 /proc/config.gz if enabled (below).
455
456config IKCONFIG_PROC
457 bool "Enable access to .config through /proc/config.gz"
458 depends on IKCONFIG && PROC_FS
459 ---help---
460 This option enables access to the kernel configuration file
461 through /proc/config.gz.
462
Alistair John Strachan794543a2007-05-08 00:31:15 -0700463config LOG_BUF_SHIFT
464 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
465 range 12 21
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700466 default 17
Alistair John Strachan794543a2007-05-08 00:31:15 -0700467 help
468 Select kernel log buffer size as a power of 2.
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700469 Examples:
470 17 => 128 KB
471 16 => 64 KB
472 15 => 32 KB
473 14 => 16 KB
Alistair John Strachan794543a2007-05-08 00:31:15 -0700474 13 => 8 KB
475 12 => 4 KB
476
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800477#
478# Architectures with an unreliable sched_clock() should select this:
479#
480config HAVE_UNSTABLE_SCHED_CLOCK
481 bool
482
Li Zefan23964d22009-01-15 13:50:58 -0800483menuconfig CGROUPS
484 boolean "Control Group support"
Kirill A. Shutemov0dea1162010-03-10 15:22:20 -0800485 depends on EVENTFD
Paul Menageddbcc7e2007-10-18 23:39:30 -0700486 help
Li Zefan23964d22009-01-15 13:50:58 -0800487 This option adds support for grouping sets of processes together, for
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800488 use with process control subsystems such as Cpusets, CFS, memory
489 controls or device isolation.
490 See
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800491 - Documentation/scheduler/sched-design-CFS.txt (CFS)
Li Zefan45ce80f2009-01-15 13:50:59 -0800492 - Documentation/cgroups/ (features for grouping, isolation
493 and resource control)
Paul Menageddbcc7e2007-10-18 23:39:30 -0700494
495 Say N if unsure.
496
Li Zefan23964d22009-01-15 13:50:58 -0800497if CGROUPS
498
Paul Menage006cb992007-10-18 23:39:43 -0700499config CGROUP_DEBUG
500 bool "Example debug cgroup subsystem"
501 depends on CGROUPS
Paul Menage418d7d82008-04-29 01:00:05 -0700502 default n
Paul Menage006cb992007-10-18 23:39:43 -0700503 help
504 This option enables a simple cgroup subsystem that
505 exports useful debugging information about the cgroups
Li Zefan23964d22009-01-15 13:50:58 -0800506 framework.
Paul Menage006cb992007-10-18 23:39:43 -0700507
Li Zefan23964d22009-01-15 13:50:58 -0800508 Say N if unsure.
Paul Menage006cb992007-10-18 23:39:43 -0700509
Serge E. Hallyn858d72e2007-10-18 23:39:45 -0700510config CGROUP_NS
Li Zefan23964d22009-01-15 13:50:58 -0800511 bool "Namespace cgroup subsystem"
512 depends on CGROUPS
513 help
514 Provides a simple namespace cgroup subsystem to
515 provide hierarchical naming of sets of namespaces,
516 for instance virtual servers and checkpoint/restart
517 jobs.
Serge E. Hallyn858d72e2007-10-18 23:39:45 -0700518
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700519config CGROUP_FREEZER
Li Zefan23964d22009-01-15 13:50:58 -0800520 bool "Freezer cgroup subsystem"
521 depends on CGROUPS
522 help
523 Provides a way to freeze and unfreeze all tasks in a
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700524 cgroup.
525
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700526config CGROUP_DEVICE
527 bool "Device controller for cgroups"
528 depends on CGROUPS && EXPERIMENTAL
529 help
530 Provides a cgroup implementing whitelists for devices which
531 a process in the cgroup can mknod or open.
532
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533config CPUSETS
534 bool "Cpuset support"
Paul Menagedb7f47c2009-04-02 16:57:55 -0700535 depends on CGROUPS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700537 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538 allow dynamically partitioning a system into sets of CPUs and
539 Memory Nodes and assigning tasks to run only within those sets.
540 This is primarily useful on large SMP or NUMA systems.
541
542 Say N if unsure.
543
Li Zefan23964d22009-01-15 13:50:58 -0800544config PROC_PID_CPUSET
545 bool "Include legacy /proc/<pid>/cpuset file"
546 depends on CPUSETS
547 default y
548
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100549config CGROUP_CPUACCT
550 bool "Simple CPU accounting cgroup subsystem"
551 depends on CGROUPS
552 help
553 Provides a simple Resource Controller for monitoring the
Li Zefan23964d22009-01-15 13:50:58 -0800554 total CPU consumed by the tasks in a cgroup.
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100555
Pavel Emelianove552b662008-02-07 00:13:49 -0800556config RESOURCE_COUNTERS
557 bool "Resource counters"
558 help
559 This option enables controller independent resource accounting
Li Zefan23964d22009-01-15 13:50:58 -0800560 infrastructure that works with cgroups.
Pavel Emelianove552b662008-02-07 00:13:49 -0800561 depends on CGROUPS
562
Balbir Singh00f0b822008-03-04 14:28:39 -0800563config CGROUP_MEM_RES_CTLR
564 bool "Memory Resource Controller for Control Groups"
565 depends on CGROUPS && RESOURCE_COUNTERS
Balbir Singhcf475ad2008-04-29 01:00:16 -0700566 select MM_OWNER
Balbir Singh00f0b822008-03-04 14:28:39 -0800567 help
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700568 Provides a memory resource controller that manages both anonymous
Thadeu Lima de Souza Cascardo21acb9c2009-02-04 10:12:08 +0100569 memory and page cache. (See Documentation/cgroups/memory.txt)
Balbir Singh00f0b822008-03-04 14:28:39 -0800570
571 Note that setting this option increases fixed memory overhead
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700572 associated with each page of memory in the system. By this,
573 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
574 usage tracking struct at boot. Total amount of this is printed out
575 at boot.
Balbir Singh00f0b822008-03-04 14:28:39 -0800576
577 Only enable when you're ok with these trade offs and really
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700578 sure you need the memory resource controller. Even when you enable
579 this, you can set "cgroup_disable=memory" at your boot option to
580 disable memory resource controller and you can avoid overheads.
Li Zefanc9d54092009-01-07 18:07:35 -0800581 (and lose benefits of memory resource controller)
Balbir Singh00f0b822008-03-04 14:28:39 -0800582
Balbir Singhcf475ad2008-04-29 01:00:16 -0700583 This config option also selects MM_OWNER config option, which
584 could in turn add some fork/exit overhead.
585
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800586config CGROUP_MEM_RES_CTLR_SWAP
KAMEZAWA Hiroyuki65e0e812010-08-10 18:02:56 -0700587 bool "Memory Resource Controller Swap Extension"
588 depends on CGROUP_MEM_RES_CTLR && SWAP
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800589 help
590 Add swap management feature to memory resource controller. When you
591 enable this, you can limit mem+swap usage per cgroup. In other words,
592 when you disable this, memory resource controller has no cares to
593 usage of swap...a process can exhaust all of the swap. This extension
594 is useful when you want to avoid exhaustion swap but this itself
595 adds more overheads and consumes memory for remembering information.
596 Especially if you use 32bit system or small memory system, please
597 be careful about enabling this. When memory resource controller
598 is disabled by boot option, this will be automatically disabled and
599 there will be no overhead from this. Even when you set this config=y,
600 if boot option "noswapaccount" is set, swap will not be accounted.
KAMEZAWA Hiroyuki627991a2009-04-02 16:57:47 -0700601 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
602 size is 4096bytes, 512k per 1Gbytes of swap.
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800603
Dhaval Giani7c941432010-01-20 13:26:18 +0100604menuconfig CGROUP_SCHED
605 bool "Group CPU scheduler"
606 depends on EXPERIMENTAL && CGROUPS
607 default n
608 help
609 This feature lets CPU scheduler recognize task groups and control CPU
610 bandwidth allocation to such task groups. It uses cgroups to group
611 tasks.
612
613if CGROUP_SCHED
614config FAIR_GROUP_SCHED
615 bool "Group scheduling for SCHED_OTHER"
616 depends on CGROUP_SCHED
617 default CGROUP_SCHED
618
619config RT_GROUP_SCHED
620 bool "Group scheduling for SCHED_RR/FIFO"
621 depends on EXPERIMENTAL
622 depends on CGROUP_SCHED
623 default n
624 help
625 This feature lets you explicitly allocate real CPU bandwidth
Li Zefan32bd7eb2010-03-24 13:17:19 +0800626 to task groups. If enabled, it will also make it impossible to
Dhaval Giani7c941432010-01-20 13:26:18 +0100627 schedule realtime tasks for non-root users until you allocate
628 realtime bandwidth for them.
629 See Documentation/scheduler/sched-rt-group.txt for more information.
630
631endif #CGROUP_SCHED
632
Vivek Goyalafc24d42010-04-26 19:27:56 +0200633config BLK_CGROUP
634 tristate "Block IO controller"
635 depends on CGROUPS && BLOCK
636 default n
637 ---help---
638 Generic block IO controller cgroup interface. This is the common
639 cgroup interface which should be used by various IO controlling
640 policies.
641
642 Currently, CFQ IO scheduler uses it to recognize task groups and
643 control disk bandwidth allocation (proportional time slice allocation)
644 to such task groups.
645
646 This option only enables generic Block IO controller infrastructure.
647 One needs to also enable actual IO controlling logic in CFQ for it
648 to take effect. (CONFIG_CFQ_GROUP_IOSCHED=y).
649
650 See Documentation/cgroups/blkio-controller.txt for more information.
651
652config DEBUG_BLK_CGROUP
653 bool "Enable Block IO controller debugging"
654 depends on BLK_CGROUP
655 default n
656 ---help---
657 Enable some debugging help. Currently it exports additional stat
658 files in a cgroup which can be useful for debugging.
659
Li Zefan23964d22009-01-15 13:50:58 -0800660endif # CGROUPS
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800661
Li Zefan23964d22009-01-15 13:50:58 -0800662config MM_OWNER
663 bool
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800664
Kay Sievers88a22c92006-09-14 11:23:28 +0200665config SYSFS_DEPRECATED
Ingo Molnard47846c2008-03-04 14:54:47 +0100666 bool
667
668config SYSFS_DEPRECATED_V2
Uwe Kleine-König9e9868a2009-12-03 19:58:00 +0100669 bool "enable deprecated sysfs features to support old userspace tools"
Randy Dunlap9148fe82007-12-31 10:05:34 -0800670 depends on SYSFS
Kay Sieversf6ee6492009-04-16 19:56:37 +0200671 default n
Ingo Molnard47846c2008-03-04 14:54:47 +0100672 select SYSFS_DEPRECATED
Kay Sievers88a22c92006-09-14 11:23:28 +0200673 help
Kay Sieversfce3e802008-11-01 14:03:00 +0100674 This option switches the layout of sysfs to the deprecated
Kay Sieversf6ee6492009-04-16 19:56:37 +0200675 version. Do not use it on recent distributions.
Kay Sievers88a22c92006-09-14 11:23:28 +0200676
Kay Sieversfce3e802008-11-01 14:03:00 +0100677 The current sysfs layout features a unified device tree at
678 /sys/devices/, which is able to express a hierarchy between
679 class devices. If the deprecated option is set to Y, the
680 unified device tree is split into a bus device tree at
681 /sys/devices/ and several individual class device trees at
682 /sys/class/. The class and bus devices will be connected by
683 "<subsystem>:<name>" and the "device" links. The "block"
684 class devices, will not show up in /sys/class/block/. Some
685 subsystems will suppress the creation of some devices which
686 depend on the unified device tree.
Kay Sievers88a22c92006-09-14 11:23:28 +0200687
Kay Sieversfce3e802008-11-01 14:03:00 +0100688 This option is not a pure compatibility option that can
689 be safely enabled on newer distributions. It will change the
690 layout of sysfs to the non-extensible deprecated version,
691 and disable some features, which can not be exported without
692 confusing older userspace tools. Since 2007/2008 all major
693 distributions do not enable this option, and ship no tools which
694 depend on the deprecated layout or this option.
695
696 If you are using a new kernel on an older distribution, or use
697 older userspace tools, you might need to say Y here. Do not say Y,
698 if the original kernel, that came with your distribution, has
699 this option set to N.
Kay Sievers88a22c92006-09-14 11:23:28 +0200700
Jens Axboeb86ff9812006-03-23 19:56:55 +0100701config RELAY
702 bool "Kernel->user space relay support (formerly relayfs)"
703 help
704 This option enables support for relay interface support in
705 certain file systems (such as debugfs).
706 It is designed to provide an efficient mechanism for tools and
707 facilities to relay large amounts of data from kernel space to
708 user space.
709
710 If unsure, say N.
711
Pavel Emelyanovc5289a692008-02-08 04:18:19 -0800712config NAMESPACES
713 bool "Namespaces support" if EMBEDDED
714 default !EMBEDDED
715 help
716 Provides the way to make tasks work with different objects using
717 the same id. For example same IPC id may refer to different objects
718 or same user id or pid may refer to different tasks when used in
719 different namespaces.
720
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -0800721config UTS_NS
722 bool "UTS namespace"
723 depends on NAMESPACES
724 help
725 In this namespace tasks see different info provided with the
726 uname() system call
727
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800728config IPC_NS
729 bool "IPC namespace"
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700730 depends on NAMESPACES && (SYSVIPC || POSIX_MQUEUE)
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800731 help
732 In this namespace tasks work with IPC ids which correspond to
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700733 different IPC objects in different namespaces.
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800734
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -0800735config USER_NS
736 bool "User namespace (EXPERIMENTAL)"
737 depends on NAMESPACES && EXPERIMENTAL
738 help
739 This allows containers, i.e. vservers, to use user namespaces
740 to provide different user info for different servers.
741 If unsure, say N.
742
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800743config PID_NS
744 bool "PID Namespaces (EXPERIMENTAL)"
745 default n
746 depends on NAMESPACES && EXPERIMENTAL
747 help
Heikki Orsila12d2b8f2008-07-06 15:48:02 +0300748 Support process id namespaces. This allows having multiple
Matt LaPlante692105b2009-01-26 11:12:25 +0100749 processes with the same pid as long as they are in different
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800750 pid namespaces. This is a building block of containers.
751
752 Unless you want to work with an experimental feature
753 say N here.
754
Matt Helsleyd6eb6332009-01-26 12:25:55 -0800755config NET_NS
756 bool "Network namespace"
757 default n
758 depends on NAMESPACES && EXPERIMENTAL && NET
759 help
760 Allow user space to create what appear to be multiple instances
761 of the network stack.
762
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -0800763config BLK_DEV_INITRD
764 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
765 depends on BROKEN || !FRV
766 help
767 The initial RAM filesystem is a ramfs which is loaded by the
768 boot loader (loadlin or lilo) and that is mounted as root
769 before the normal boot procedure. It is typically used to
770 load modules needed to mount the "real" root file system,
771 etc. See <file:Documentation/initrd.txt> for details.
772
773 If RAM disk support (BLK_DEV_RAM) is also included, this
774 also enables initial RAM disk (initrd) support and adds
775 15 Kbytes (more on some other architectures) to the kernel size.
776
777 If unsure say Y.
778
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800779if BLK_DEV_INITRD
780
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200781source "usr/Kconfig"
782
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800783endif
784
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800785config CC_OPTIMIZE_FOR_SIZE
Ingo Molnar96fffeb2008-04-28 01:39:43 +0200786 bool "Optimize for size"
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800787 default y
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800788 help
789 Enabling this option will pass "-Os" instead of "-O2" to gcc
790 resulting in a smaller kernel.
791
jkacur775a7222008-07-16 00:31:16 +0200792 If unsure, say Y.
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800793
Randy Dunlap08470622006-09-30 23:28:13 -0700794config SYSCTL
795 bool
796
Randy Dunlapb943c462009-03-10 12:55:46 -0700797config ANON_INODES
798 bool
799
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800menuconfig EMBEDDED
801 bool "Configure standard kernel features (for small systems)"
802 help
803 This option allows certain base kernel options and settings
804 to be disabled or tweaked. This is for specialized
805 environments which can tolerate a "non-standard" kernel.
806 Only use this if you really know what you are doing.
807
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700808config UID16
809 bool "Enable 16-bit UID system calls" if EMBEDDED
David S. Miller09337f52008-04-26 03:17:12 -0700810 depends on ARM || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && COMPAT) || UML || (X86_64 && IA32_EMULATION)
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700811 default y
812 help
813 This enables the legacy 16-bit UID syscall wrappers.
814
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700815config SYSCTL_SYSCALL
Randy Dunlap08470622006-09-30 23:28:13 -0700816 bool "Sysctl syscall support" if EMBEDDED
Eric W. Biederman26a70342009-11-05 05:26:41 -0800817 depends on PROC_SYSCTL
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800818 default y
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700819 select SYSCTL
820 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800821 sys_sysctl uses binary paths that have been found challenging
822 to properly maintain and use. The interface in /proc/sys
823 using paths with ascii names is now the primary path to this
824 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700825
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800826 Almost nothing using the binary sysctl interface so if you are
827 trying to save some space it is probably safe to disable this,
828 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700829
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800830 If unsure say Y here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700831
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832config KALLSYMS
Jesper Juhl979c6a12006-12-12 19:25:11 +0100833 bool "Load all symbols for debugging/ksymoops" if EMBEDDED
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834 default y
835 help
836 Say Y here to let the kernel print out symbolic crash information and
837 symbolic stack backtraces. This increases the size of the kernel
838 somewhat, as all symbols have to be loaded into the kernel image.
839
840config KALLSYMS_ALL
841 bool "Include all symbols in kallsyms"
842 depends on DEBUG_KERNEL && KALLSYMS
843 help
844 Normally kallsyms only contains the symbols of functions, for nicer
845 OOPS messages. Some debuggers can use kallsyms for other
Jesper Juhlf9f97bc2005-07-20 05:43:05 +0200846 symbols too: say Y here to include all symbols, if you need them
847 and you don't care about adding 300k to the size of your kernel.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848
849 Say N.
850
851config KALLSYMS_EXTRA_PASS
852 bool "Do an extra kallsyms pass"
853 depends on KALLSYMS
854 help
855 If kallsyms is not working correctly, the build will fail with
856 inconsistent kallsyms data. If that occurs, log a bug report and
857 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
858 Always say N here unless you find a bug in kallsyms, which must be
859 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
860 you wait for kallsyms to be fixed.
861
Matt Mackalld59745c2005-05-01 08:59:02 -0700862
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -0800863config HOTPLUG
864 bool "Support for hot-pluggable devices" if EMBEDDED
865 default y
866 help
867 This option is provided for the case where no hotplug or uevent
868 capabilities is wanted by the kernel. You should only consider
869 disabling this option for embedded systems that do not use modules, a
870 dynamic /dev tree, or dynamic device discovery. Just say Y.
871
Matt Mackalld59745c2005-05-01 08:59:02 -0700872config PRINTK
873 default y
874 bool "Enable support for printk" if EMBEDDED
875 help
876 This option enables normal printk support. Removing it
877 eliminates most of the message strings from the kernel image
878 and makes the kernel more or less silent. As this makes it
879 very difficult to diagnose system problems, saying N here is
880 strongly discouraged.
881
Matt Mackallc8538a72005-05-01 08:59:01 -0700882config BUG
883 bool "BUG() support" if EMBEDDED
884 default y
885 help
886 Disabling this option eliminates support for BUG and WARN, reducing
887 the size of your kernel image and potentially quietly ignoring
888 numerous fatal conditions. You should only consider disabling this
889 option for embedded systems with no facilities for reporting errors.
890 Just say Y.
891
Matt Mackall708e9a72006-01-08 01:05:25 -0800892config ELF_CORE
893 default y
894 bool "Enable ELF core dumps" if EMBEDDED
895 help
896 Enable support for generating core dumps. Disabling saves about 4k.
897
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +0200898config PCSPKR_PLATFORM
899 bool "Enable PC-Speaker support" if EMBEDDED
900 depends on ALPHA || X86 || MIPS || PPC_PREP || PPC_CHRP || PPC_PSERIES
901 default y
902 help
903 This option allows to disable the internal PC-Speaker
904 support, saving some memory.
905
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906config BASE_FULL
907 default y
908 bool "Enable full-sized data structures for core" if EMBEDDED
909 help
910 Disabling this option reduces the size of miscellaneous core
911 kernel data structures. This saves memory on small machines,
912 but may reduce performance.
913
914config FUTEX
915 bool "Enable futex support" if EMBEDDED
916 default y
Ingo Molnar23f78d4a2006-06-27 02:54:53 -0700917 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918 help
919 Disabling this option will cause the kernel to be built without
920 support for "fast userspace mutexes". The resulting kernel may not
921 run glibc-based applications correctly.
922
923config EPOLL
924 bool "Enable eventpoll support" if EMBEDDED
925 default y
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700926 select ANON_INODES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927 help
928 Disabling this option will cause the kernel to be built without
929 support for epoll family of system calls.
930
Davide Libenzifba2afa2007-05-10 22:23:13 -0700931config SIGNALFD
932 bool "Enable signalfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700933 select ANON_INODES
Davide Libenzifba2afa2007-05-10 22:23:13 -0700934 default y
935 help
936 Enable the signalfd() system call that allows to receive signals
937 on a file descriptor.
938
939 If unsure, say Y.
940
Davide Libenzib215e282007-05-10 22:23:16 -0700941config TIMERFD
942 bool "Enable timerfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700943 select ANON_INODES
Davide Libenzib215e282007-05-10 22:23:16 -0700944 default y
945 help
946 Enable the timerfd() system call that allows to receive timer
947 events on a file descriptor.
948
949 If unsure, say Y.
950
Davide Libenzie1ad7462007-05-10 22:23:19 -0700951config EVENTFD
952 bool "Enable eventfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700953 select ANON_INODES
Davide Libenzie1ad7462007-05-10 22:23:19 -0700954 default y
955 help
956 Enable the eventfd() system call that allows to receive both
957 kernel notification (ie. KAIO) or userspace notifications.
958
959 If unsure, say Y.
960
Linus Torvalds1da177e2005-04-16 15:20:36 -0700961config SHMEM
962 bool "Use full shmem filesystem" if EMBEDDED
963 default y
964 depends on MMU
965 help
966 The shmem is an internal filesystem used to manage shared memory.
967 It is backed by swap and manages resource limits. It is also exported
968 to userspace as tmpfs if TMPFS is enabled. Disabling this
969 option replaces shmem and tmpfs with the much simpler ramfs code,
970 which may be appropriate on small systems without swap.
971
Thomas Petazzoniebf3f092008-10-15 22:05:12 -0700972config AIO
973 bool "Enable AIO support" if EMBEDDED
974 default y
975 help
976 This option enables POSIX asynchronous I/O which may by used
977 by some high performance threaded applications. Disabling
978 this option saves about 7k.
979
Ingo Molnarcdd6c482009-09-21 12:02:48 +0200980config HAVE_PERF_EVENTS
Thomas Gleixner0793a612008-12-04 20:12:29 +0100981 bool
Mike Frysinger018df722009-06-12 13:17:43 -0400982 help
983 See tools/perf/design.txt for details.
Thomas Gleixner0793a612008-12-04 20:12:29 +0100984
Peter Zijlstra906010b2009-09-21 16:08:49 +0200985config PERF_USE_VMALLOC
986 bool
987 help
988 See tools/perf/design.txt for details
989
Ingo Molnar57c0c152009-09-21 12:20:38 +0200990menu "Kernel Performance Events And Counters"
Thomas Gleixner0793a612008-12-04 20:12:29 +0100991
Ingo Molnarcdd6c482009-09-21 12:02:48 +0200992config PERF_EVENTS
Ingo Molnar57c0c152009-09-21 12:20:38 +0200993 bool "Kernel performance events and counters"
994 default y if (PROFILING || PERF_COUNTERS)
Ingo Molnarcdd6c482009-09-21 12:02:48 +0200995 depends on HAVE_PERF_EVENTS
Ingo Molnar4c59e462008-12-08 19:38:33 +0100996 select ANON_INODES
Peter Zijlstrae360adb2010-10-14 14:01:34 +0800997 select IRQ_WORK
Thomas Gleixner0793a612008-12-04 20:12:29 +0100998 help
Ingo Molnar57c0c152009-09-21 12:20:38 +0200999 Enable kernel support for various performance events provided
1000 by software and hardware.
Thomas Gleixner0793a612008-12-04 20:12:29 +01001001
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001002 Software events are supported either built-in or via the
Ingo Molnar57c0c152009-09-21 12:20:38 +02001003 use of generic tracepoints.
1004
1005 Most modern CPUs support performance events via performance
1006 counter registers. These registers count the number of certain
Thomas Gleixner0793a612008-12-04 20:12:29 +01001007 types of hw events: such as instructions executed, cachemisses
1008 suffered, or branches mis-predicted - without slowing down the
1009 kernel or applications. These registers can also trigger interrupts
1010 when a threshold number of events have passed - and can thus be
1011 used to profile the code that runs on that CPU.
1012
Ingo Molnar57c0c152009-09-21 12:20:38 +02001013 The Linux Performance Event subsystem provides an abstraction of
Thadeu Lima de Souza Cascardodd770382009-10-30 19:32:25 -02001014 these software and hardware event capabilities, available via a
Ingo Molnar57c0c152009-09-21 12:20:38 +02001015 system call and used by the "perf" utility in tools/perf/. It
Thomas Gleixner0793a612008-12-04 20:12:29 +01001016 provides per task and per CPU counters, and it provides event
1017 capabilities on top of those.
1018
1019 Say Y if unsure.
1020
Ingo Molnar57c0c152009-09-21 12:20:38 +02001021config PERF_COUNTERS
1022 bool "Kernel performance counters (old config option)"
1023 depends on HAVE_PERF_EVENTS
1024 help
1025 This config has been obsoleted by the PERF_EVENTS
1026 config option - please see that one for details.
1027
1028 It has no effect on the kernel whether you enable
1029 it or not, it is a compatibility placeholder.
1030
1031 Say N if unsure.
1032
Peter Zijlstra906010b2009-09-21 16:08:49 +02001033config DEBUG_PERF_USE_VMALLOC
1034 default n
1035 bool "Debug: use vmalloc to back perf mmap() buffers"
1036 depends on PERF_EVENTS && DEBUG_KERNEL
1037 select PERF_USE_VMALLOC
1038 help
1039 Use vmalloc memory to back perf mmap() buffers.
1040
1041 Mostly useful for debugging the vmalloc code on platforms
1042 that don't require it.
1043
1044 Say N if unsure.
1045
Thomas Gleixner0793a612008-12-04 20:12:29 +01001046endmenu
1047
Christoph Lameterf8891e52006-06-30 01:55:45 -07001048config VM_EVENT_COUNTERS
1049 default y
1050 bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
1051 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -08001052 VM event counters are needed for event counts to be shown.
1053 This option allows the disabling of the VM event counters
1054 on EMBEDDED systems. /proc/vmstat will only show page counts
1055 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -07001056
Thomas Petazzoni3d137312008-08-19 10:28:24 +02001057config PCI_QUIRKS
1058 default y
Geert Uytterhoeven61cfc7e2008-10-22 08:53:25 +02001059 bool "Enable PCI quirk workarounds" if EMBEDDED
1060 depends on PCI
Thomas Petazzoni3d137312008-08-19 10:28:24 +02001061 help
1062 This enables workarounds for various PCI chipset
1063 bugs/quirks. Disable this only if your target machine is
1064 unaffected by PCI quirks.
1065
Christoph Lameter41ecc552007-05-09 02:32:44 -07001066config SLUB_DEBUG
1067 default y
1068 bool "Enable SLUB debugging support" if EMBEDDED
Christoph Lameterf6acb632008-04-29 16:16:06 -07001069 depends on SLUB && SYSFS
Christoph Lameter41ecc552007-05-09 02:32:44 -07001070 help
1071 SLUB has extensive debug support features. Disabling these can
1072 result in significant savings in code size. This also disables
1073 SLUB sysfs support. /sys/slab will not exist and there will be
1074 no support for cache validation etc.
1075
Randy Dunlapb943c462009-03-10 12:55:46 -07001076config COMPAT_BRK
1077 bool "Disable heap randomization"
1078 default y
1079 help
1080 Randomizing heap placement makes heap exploits harder, but it
1081 also breaks ancient binaries (including anything libc5 based).
1082 This option changes the bootup default to heap randomization
Matt LaPlante692105b2009-01-26 11:12:25 +01001083 disabled, and can be overridden at runtime by setting
Randy Dunlapb943c462009-03-10 12:55:46 -07001084 /proc/sys/kernel/randomize_va_space to 2.
1085
1086 On non-ancient distros (post-2000 ones) N is usually a safe choice.
1087
Christoph Lameter81819f02007-05-06 14:49:36 -07001088choice
1089 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -07001090 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001091 help
1092 This option allows to select a slab allocator.
1093
1094config SLAB
1095 bool "SLAB"
1096 help
1097 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -07001098 well in all environments. It organizes cache hot objects in
Simon Arlott02f56212008-11-05 22:18:19 +00001099 per cpu and per node queues.
Christoph Lameter81819f02007-05-06 14:49:36 -07001100
1101config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001102 bool "SLUB (Unqueued Allocator)"
1103 help
1104 SLUB is a slab allocator that minimizes cache line usage
1105 instead of managing queues of cached objects (SLAB approach).
1106 Per cpu caching is realized using slabs of objects instead
1107 of queues of objects. SLUB can use memory efficiently
Simon Arlott02f56212008-11-05 22:18:19 +00001108 and has enhanced diagnostics. SLUB is the default choice for
1109 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -07001110
1111config SLOB
Paul Mundt84a01c22007-07-15 23:38:24 -07001112 depends on EMBEDDED
Christoph Lameter81819f02007-05-06 14:49:36 -07001113 bool "SLOB (Simple Allocator)"
1114 help
Matt Mackall37291452008-02-04 22:29:38 -08001115 SLOB replaces the stock allocator with a drastically simpler
1116 allocator. SLOB is generally more space efficient but
1117 does not perform as well on large systems.
Christoph Lameter81819f02007-05-06 14:49:36 -07001118
1119endchoice
1120
Jie Zhangea637632009-12-14 18:00:02 -08001121config MMAP_ALLOW_UNINITIALIZED
1122 bool "Allow mmapped anonymous memory to be uninitialized"
1123 depends on EMBEDDED && !MMU
1124 default n
1125 help
1126 Normally, and according to the Linux spec, anonymous memory obtained
1127 from mmap() has it's contents cleared before it is passed to
1128 userspace. Enabling this config option allows you to request that
1129 mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus
1130 providing a huge performance boost. If this option is not enabled,
1131 then the flag will be ignored.
1132
1133 This is taken advantage of by uClibc's malloc(), and also by
1134 ELF-FDPIC binfmt's brk and stack allocator.
1135
1136 Because of the obvious security issues, this option should only be
1137 enabled on embedded devices where you control what is run in
1138 userspace. Since that isn't generally a problem on no-MMU systems,
1139 it is normally safe to say Y here.
1140
1141 See Documentation/nommu-mmap.txt for more information.
1142
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001143config PROFILING
Robert Richterb309a292010-02-26 15:01:23 +01001144 bool "Profiling support"
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001145 help
1146 Say Y here to enable the extended profiling support mechanisms used
1147 by profilers such as OProfile.
1148
Ingo Molnar5f87f112008-07-23 14:15:22 +02001149#
1150# Place an empty function call at each tracepoint site. Can be
1151# dynamically changed for a probe function.
1152#
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001153config TRACEPOINTS
Ingo Molnar5f87f112008-07-23 14:15:22 +02001154 bool
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001155
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -05001156source "arch/Kconfig"
1157
Linus Torvalds1da177e2005-04-16 15:20:36 -07001158endmenu # General setup
1159
Dmitry Baryshkovee7e5512008-06-29 14:18:46 +04001160config HAVE_GENERIC_DMA_COHERENT
1161 bool
1162 default n
1163
Linus Torvalds158a9622008-01-02 13:04:48 -08001164config SLABINFO
1165 bool
1166 depends on PROC_FS
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001167 depends on SLAB || SLUB_DEBUG
Linus Torvalds158a9622008-01-02 13:04:48 -08001168 default y
1169
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001170config RT_MUTEXES
1171 boolean
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001172
Linus Torvalds1da177e2005-04-16 15:20:36 -07001173config BASE_SMALL
1174 int
1175 default 0 if BASE_FULL
1176 default 1 if !BASE_FULL
1177
Jan Engelhardt66da5732007-07-15 23:39:29 -07001178menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001179 bool "Enable loadable module support"
1180 help
1181 Kernel modules are small pieces of compiled code which can
1182 be inserted in the running kernel, rather than being
1183 permanently built into the kernel. You use the "modprobe"
1184 tool to add (and sometimes remove) them. If you say Y here,
1185 many parts of the kernel can be built as modules (by
1186 answering M instead of Y where indicated): this is most
1187 useful for infrequently used options which are not required
1188 for booting. For more information, see the man pages for
1189 modprobe, lsmod, modinfo, insmod and rmmod.
1190
1191 If you say Y here, you will need to run "make
1192 modules_install" to put the modules under /lib/modules/
1193 where modprobe can find them (you may need to be root to do
1194 this).
1195
1196 If unsure, say Y.
1197
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001198if MODULES
1199
Linus Torvalds826e4502008-05-04 17:04:16 -07001200config MODULE_FORCE_LOAD
1201 bool "Forced module loading"
Linus Torvalds826e4502008-05-04 17:04:16 -07001202 default n
1203 help
Rusty Russell91e37a72008-05-09 16:25:28 +10001204 Allow loading of modules without version information (ie. modprobe
1205 --force). Forced module loading sets the 'F' (forced) taint flag and
1206 is usually a really bad idea.
Linus Torvalds826e4502008-05-04 17:04:16 -07001207
Linus Torvalds1da177e2005-04-16 15:20:36 -07001208config MODULE_UNLOAD
1209 bool "Module unloading"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001210 help
1211 Without this option you will not be able to unload any
1212 modules (note that some modules may not be unloadable
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001213 anyway), which makes your kernel smaller, faster
1214 and simpler. If unsure, say Y.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001215
1216config MODULE_FORCE_UNLOAD
1217 bool "Forced module unloading"
1218 depends on MODULE_UNLOAD && EXPERIMENTAL
1219 help
1220 This option allows you to force a module to unload, even if the
1221 kernel believes it is unsafe: the kernel will remove the module
1222 without waiting for anyone to stop using it (using the -f option to
1223 rmmod). This is mainly for kernel developers and desperate users.
1224 If unsure, say N.
1225
Linus Torvalds1da177e2005-04-16 15:20:36 -07001226config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +01001227 bool "Module versioning support"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001228 help
1229 Usually, you have to use modules compiled with your kernel.
1230 Saying Y here makes it sometimes possible to use modules
1231 compiled for different kernels, by adding enough information
1232 to the modules to (hopefully) spot any changes which would
1233 make them incompatible with the kernel you are running. If
1234 unsure, say N.
1235
1236config MODULE_SRCVERSION_ALL
1237 bool "Source checksum for all modules"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238 help
1239 Modules which contain a MODULE_VERSION get an extra "srcversion"
1240 field inserted into their modinfo section, which contains a
1241 sum of the source files which made it. This helps maintainers
1242 see exactly which source was used to build a module (since
1243 others sometimes change the module source without updating
1244 the version). With this option, such a "srcversion" field
1245 will be created for all modules. If unsure, say N.
1246
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001247endif # MODULES
1248
Rusty Russell98a79d62008-12-13 21:19:41 +10301249config INIT_ALL_POSSIBLE
1250 bool
1251 help
1252 Back when each arch used to define their own cpu_online_map and
1253 cpu_possible_map, some of them chose to initialize cpu_possible_map
1254 with all 1s, and others with all 0s. When they were centralised,
1255 it was better to provide this option than to break all the archs
Matt LaPlante692105b2009-01-26 11:12:25 +01001256 and have several arch maintainers pursuing me down dark alleys.
Rusty Russell98a79d62008-12-13 21:19:41 +10301257
Linus Torvalds1da177e2005-04-16 15:20:36 -07001258config STOP_MACHINE
1259 bool
1260 default y
1261 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
1262 help
1263 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001264
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001265source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -07001266
1267config PREEMPT_NOTIFIERS
1268 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +01001269
Steffen Klassert16295be2010-01-06 19:47:10 +11001270config PADATA
1271 depends on SMP
1272 bool
1273
Thomas Gleixner6beb0002009-11-09 15:21:34 +00001274source "kernel/Kconfig.locks"