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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
Al Boldiff0cfc62007-07-31 00:39:23 -070024menu "General setup"
Linus Torvalds1da177e2005-04-16 15:20:36 -070025
26config EXPERIMENTAL
27 bool "Prompt for development and/or incomplete code/drivers"
28 ---help---
29 Some of the various things that Linux supports (such as network
30 drivers, file systems, network protocols, etc.) can be in a state
31 of development where the functionality, stability, or the level of
32 testing is not yet high enough for general use. This is usually
33 known as the "alpha-test" phase among developers. If a feature is
34 currently in alpha-test, then the developers usually discourage
35 uninformed widespread use of this feature by the general public to
36 avoid "Why doesn't this work?" type mail messages. However, active
37 testing and use of these systems is welcomed. Just be aware that it
38 may not meet the normal level of reliability or it may fail to work
39 in some special cases. Detailed bug reports from people familiar
40 with the kernel internals are usually welcomed by the developers
41 (before submitting bug reports, please read the documents
42 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
43 <file:Documentation/BUG-HUNTING>, and
44 <file:Documentation/oops-tracing.txt> in the kernel source).
45
46 This option will also make obsoleted drivers available. These are
47 drivers that have been replaced by something else, and/or are
48 scheduled to be removed in a future kernel release.
49
50 Unless you intend to help test and develop a feature or driver that
51 falls into this category, or you have a situation that requires
52 using these features, you should probably say N here, which will
53 cause the configurator to present you with fewer choices. If
54 you say Y here, you will be offered the choice of using features or
55 drivers that are currently considered to be in the alpha-test phase.
56
Linus Torvalds1da177e2005-04-16 15:20:36 -070057config BROKEN
58 bool
Linus Torvalds1da177e2005-04-16 15:20:36 -070059
60config BROKEN_ON_SMP
61 bool
62 depends on BROKEN || !SMP
63 default y
64
65config LOCK_KERNEL
66 bool
67 depends on SMP || PREEMPT
68 default y
69
70config INIT_ENV_ARG_LIMIT
71 int
Adrian Bunkdd673bc2006-06-30 01:55:51 -070072 default 32 if !UML
73 default 128 if UML
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 help
Randy Dunlap34ad92c22005-10-30 15:01:46 -080075 Maximum of each of the number of arguments and environment
76 variables passed to init from the kernel command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
79config LOCALVERSION
80 string "Local version - append to kernel release"
81 help
82 Append an extra string to the end of your kernel version.
83 This will show up when you type uname, for example.
84 The string you set here will be appended after the contents of
85 any files with a filename matching localversion* in your
86 object and source tree, in that order. Your total string can
87 be a maximum of 64 characters.
88
Ryan Andersonaaebf432005-07-31 04:57:49 -040089config LOCALVERSION_AUTO
90 bool "Automatically append version information to the version string"
91 default y
92 help
93 This will try to automatically determine if the current tree is a
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020094 release tree by looking for git tags that belong to the current
95 top of tree revision.
Ryan Andersonaaebf432005-07-31 04:57:49 -040096
97 A string of the format -gxxxxxxxx will be added to the localversion
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020098 if a git-based tree is found. The string generated by this will be
Ryan Andersonaaebf432005-07-31 04:57:49 -040099 appended after any matching localversion* files, and after the value
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200100 set in CONFIG_LOCALVERSION.
Ryan Andersonaaebf432005-07-31 04:57:49 -0400101
Robert P. J. Day6e5a5422007-05-01 23:08:11 +0200102 (The actual string used here is the first eight characters produced
103 by running the command:
104
105 $ git rev-parse --verify HEAD
106
107 which is done within the script "scripts/setlocalversion".)
Ryan Andersonaaebf432005-07-31 04:57:49 -0400108
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800109config HAVE_KERNEL_GZIP
110 bool
111
112config HAVE_KERNEL_BZIP2
113 bool
114
115config HAVE_KERNEL_LZMA
116 bool
117
Alain Knaff30d65db2009-01-04 22:46:17 +0100118choice
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800119 prompt "Kernel compression mode"
120 default KERNEL_GZIP
121 depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA
122 help
Alain Knaff30d65db2009-01-04 22:46:17 +0100123 The linux kernel is a kind of self-extracting executable.
124 Several compression algorithms are available, which differ
125 in efficiency, compression and decompression speed.
126 Compression speed is only relevant when building a kernel.
127 Decompression speed is relevant at each boot.
128
129 If you have any problems with bzip2 or lzma compressed
130 kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
131 version of this functionality (bzip2 only), for 2.4, was
132 supplied by Christian Ludwig)
133
134 High compression options are mostly useful for users, who
135 are low on disk space (embedded systems), but for whom ram
136 size matters less.
137
138 If in doubt, select 'gzip'
139
140config KERNEL_GZIP
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800141 bool "Gzip"
142 depends on HAVE_KERNEL_GZIP
143 help
144 The old and tried gzip compression. Its compression ratio is
145 the poorest among the 3 choices; however its speed (both
146 compression and decompression) is the fastest.
Alain Knaff30d65db2009-01-04 22:46:17 +0100147
148config KERNEL_BZIP2
149 bool "Bzip2"
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800150 depends on HAVE_KERNEL_BZIP2
Alain Knaff30d65db2009-01-04 22:46:17 +0100151 help
152 Its compression ratio and speed is intermediate.
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800153 Decompression speed is slowest among the three. The kernel
154 size is about 10% smaller with bzip2, in comparison to gzip.
155 Bzip2 uses a large amount of memory. For modern kernels you
156 will need at least 8MB RAM or more for booting.
Alain Knaff30d65db2009-01-04 22:46:17 +0100157
158config KERNEL_LZMA
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800159 bool "LZMA"
160 depends on HAVE_KERNEL_LZMA
161 help
162 The most recent compression algorithm.
163 Its ratio is best, decompression speed is between the other
164 two. Compression is slowest. The kernel size is about 33%
165 smaller with LZMA in comparison to gzip.
Alain Knaff30d65db2009-01-04 22:46:17 +0100166
167endchoice
168
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169config SWAP
170 bool "Support for paging of anonymous memory (swap)"
David Howells93614012006-09-30 20:45:40 +0200171 depends on MMU && BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 default y
173 help
174 This option allows you to choose whether you want to have support
Jesper Juhl92c35042006-01-15 02:40:08 +0100175 for so called swap devices or swap files in your kernel that are
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 used to provide more virtual memory than the actual RAM present
177 in your computer. If unsure say Y.
178
179config SYSVIPC
180 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 ---help---
182 Inter Process Communication is a suite of library functions and
183 system calls which let processes (running programs) synchronize and
184 exchange information. It is generally considered to be a good thing,
185 and some programs won't run unless you say Y here. In particular, if
186 you want to run the DOS emulator dosemu under Linux (read the
187 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
188 you'll need to say Y here.
189
190 You can find documentation about IPC with "info ipc" and also in
191 section 6.4 of the Linux Programmer's Guide, available from
192 <http://www.tldp.org/guides.html>.
193
Eric W. Biedermana5494dc2007-02-14 00:34:06 -0800194config SYSVIPC_SYSCTL
195 bool
196 depends on SYSVIPC
197 depends on SYSCTL
198 default y
199
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200config POSIX_MQUEUE
201 bool "POSIX Message Queues"
202 depends on NET && EXPERIMENTAL
203 ---help---
204 POSIX variant of message queues is a part of IPC. In POSIX message
205 queues every message has a priority which decides about succession
206 of receiving it by a process. If you want to compile and run
207 programs written e.g. for Solaris with use of its POSIX message
Robert P. J. Dayb0e37652007-05-09 07:25:13 +0200208 queues (functions mq_*) say Y here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209
210 POSIX message queues are visible as a filesystem called 'mqueue'
211 and can be mounted somewhere if you want to do filesystem
212 operations on message queues.
213
214 If unsure, say Y.
215
Serge E. Hallynbdc8e5f2009-04-06 19:01:11 -0700216config POSIX_MQUEUE_SYSCTL
217 bool
218 depends on POSIX_MQUEUE
219 depends on SYSCTL
220 default y
221
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222config BSD_PROCESS_ACCT
223 bool "BSD Process Accounting"
224 help
225 If you say Y here, a user level program will be able to instruct the
226 kernel (via a special system call) to write process accounting
227 information to a file: whenever a process exits, information about
228 that process will be appended to the file by the kernel. The
229 information includes things such as creation time, owning user,
230 command name, memory usage, controlling terminal etc. (the complete
231 list is in the struct acct in <file:include/linux/acct.h>). It is
232 up to the user level program to do useful things with this
233 information. This is generally a good idea, so say Y.
234
235config BSD_PROCESS_ACCT_V3
236 bool "BSD Process Accounting version 3 file format"
237 depends on BSD_PROCESS_ACCT
238 default n
239 help
240 If you say Y here, the process accounting information is written
241 in a new file format that also logs the process IDs of each
242 process and it's parent. Note that this file format is incompatible
243 with previous v0/v1/v2 file formats, so you will need updated tools
244 for processing it. A preliminary version of these tools is available
S.Çağlar Onur37a4c942008-06-18 11:45:13 +0300245 at <http://www.gnu.org/software/acct/>.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246
Shailabh Nagarc7572492006-07-14 00:24:40 -0700247config TASKSTATS
248 bool "Export task/process statistics through netlink (EXPERIMENTAL)"
249 depends on NET
250 default n
251 help
252 Export selected statistics for tasks/processes through the
253 generic netlink interface. Unlike BSD process accounting, the
254 statistics are available during the lifetime of tasks/processes as
255 responses to commands. Like BSD accounting, they are sent to user
256 space on task exit.
257
258 Say N if unsure.
259
Shailabh Nagarca74e922006-07-14 00:24:36 -0700260config TASK_DELAY_ACCT
261 bool "Enable per-task delay accounting (EXPERIMENTAL)"
Shailabh Nagar6f449932006-07-14 00:24:41 -0700262 depends on TASKSTATS
Shailabh Nagarca74e922006-07-14 00:24:36 -0700263 help
264 Collect information on time spent by a task waiting for system
265 resources like cpu, synchronous block I/O completion and swapping
266 in pages. Such statistics can help in setting a task's priorities
267 relative to other tasks for cpu, io, rss limits etc.
268
269 Say N if unsure.
270
Alexey Dobriyan18f705f2007-02-10 01:46:44 -0800271config TASK_XACCT
272 bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
273 depends on TASKSTATS
274 help
275 Collect extended task accounting data and send the data
276 to userland for processing over the taskstats interface.
277
278 Say N if unsure.
279
280config TASK_IO_ACCOUNTING
281 bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
282 depends on TASK_XACCT
283 help
284 Collect information on the number of bytes of storage I/O which this
285 task has caused.
286
287 Say N if unsure.
288
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289config AUDIT
290 bool "Auditing support"
Chris Wright804a6a492005-05-11 10:52:45 +0100291 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 help
293 Enable auditing infrastructure that can be used with another
294 kernel subsystem, such as SELinux (which requires this for
295 logging of avc messages output). Does not do system-call
296 auditing without CONFIG_AUDITSYSCALL.
297
298config AUDITSYSCALL
299 bool "Enable system-call auditing support"
Yuichi Nakamura1322b9d2007-11-10 19:21:34 +0900300 depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64|| SUPERH)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 default y if SECURITY_SELINUX
302 help
303 Enable low-overhead system-call auditing infrastructure that
304 can be used independently or with another kernel subsystem,
Amy Griffisf368c07d2006-04-07 16:55:56 -0400305 such as SELinux. To use audit's filesystem watch feature, please
306 ensure that INOTIFY is configured.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307
Al Viro74c3cbe2007-07-22 08:04:18 -0400308config AUDIT_TREE
309 def_bool y
Eric Paris63c882a2009-05-21 17:02:01 -0400310 depends on AUDITSYSCALL
311 select INOTIFY
Al Viro74c3cbe2007-07-22 08:04:18 -0400312
Mike Travisc903ff82009-01-15 12:28:29 -0800313menu "RCU Subsystem"
314
315choice
316 prompt "RCU Implementation"
Paul E. McKenney31c9a242009-04-02 21:06:25 -0700317 default TREE_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800318
319config CLASSIC_RCU
320 bool "Classic RCU"
321 help
322 This option selects the classic RCU implementation that is
323 designed for best read-side performance on non-realtime
324 systems.
325
326 Select this option if you are unsure.
327
328config TREE_RCU
329 bool "Tree-based hierarchical RCU"
330 help
331 This option selects the RCU implementation that is
332 designed for very large SMP system with hundreds or
333 thousands of CPUs.
334
335config PREEMPT_RCU
336 bool "Preemptible RCU"
337 depends on PREEMPT
338 help
339 This option reduces the latency of the kernel by making certain
340 RCU sections preemptible. Normally RCU code is non-preemptible, if
341 this option is selected then read-only RCU sections become
342 preemptible. This helps latency, but may expose bugs due to
343 now-naive assumptions about each RCU read-side critical section
344 remaining on a given CPU through its execution.
345
346endchoice
347
348config RCU_TRACE
349 bool "Enable tracing for RCU"
350 depends on TREE_RCU || PREEMPT_RCU
351 help
352 This option provides tracing in RCU which presents stats
353 in debugfs for debugging RCU implementation.
354
355 Say Y here if you want to enable RCU tracing
356 Say N if you are unsure.
357
358config RCU_FANOUT
359 int "Tree-based hierarchical RCU fanout value"
360 range 2 64 if 64BIT
361 range 2 32 if !64BIT
362 depends on TREE_RCU
363 default 64 if 64BIT
364 default 32 if !64BIT
365 help
366 This option controls the fanout of hierarchical implementations
367 of RCU, allowing RCU to work efficiently on machines with
368 large numbers of CPUs. This value must be at least the cube
369 root of NR_CPUS, which allows NR_CPUS up to 32,768 for 32-bit
370 systems and up to 262,144 for 64-bit systems.
371
372 Select a specific number if testing RCU itself.
373 Take the default if unsure.
374
375config RCU_FANOUT_EXACT
376 bool "Disable tree-based hierarchical RCU auto-balancing"
377 depends on TREE_RCU
378 default n
379 help
380 This option forces use of the exact RCU_FANOUT value specified,
381 regardless of imbalances in the hierarchy. This is useful for
382 testing RCU itself, and might one day be useful on systems with
383 strong NUMA behavior.
384
385 Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
386
387 Say N if unsure.
388
389config TREE_RCU_TRACE
390 def_bool RCU_TRACE && TREE_RCU
391 select DEBUG_FS
392 help
393 This option provides tracing for the TREE_RCU implementation,
394 permitting Makefile to trivially select kernel/rcutree_trace.c.
395
396config PREEMPT_RCU_TRACE
397 def_bool RCU_TRACE && PREEMPT_RCU
398 select DEBUG_FS
399 help
400 This option provides tracing for the PREEMPT_RCU implementation,
401 permitting Makefile to trivially select kernel/rcupreempt_trace.c.
402
403endmenu # "RCU Subsystem"
404
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700406 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 ---help---
408 This option enables the complete Linux kernel ".config" file
409 contents to be saved in the kernel. It provides documentation
410 of which kernel options are used in a running kernel or in an
411 on-disk kernel. This information can be extracted from the kernel
412 image file with the script scripts/extract-ikconfig and used as
413 input to rebuild the current kernel or to build another kernel.
414 It can also be extracted from a running kernel by reading
415 /proc/config.gz if enabled (below).
416
417config IKCONFIG_PROC
418 bool "Enable access to .config through /proc/config.gz"
419 depends on IKCONFIG && PROC_FS
420 ---help---
421 This option enables access to the kernel configuration file
422 through /proc/config.gz.
423
Alistair John Strachan794543a2007-05-08 00:31:15 -0700424config LOG_BUF_SHIFT
425 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
426 range 12 21
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700427 default 17
Alistair John Strachan794543a2007-05-08 00:31:15 -0700428 help
429 Select kernel log buffer size as a power of 2.
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700430 Examples:
431 17 => 128 KB
432 16 => 64 KB
433 15 => 32 KB
434 14 => 16 KB
Alistair John Strachan794543a2007-05-08 00:31:15 -0700435 13 => 8 KB
436 12 => 4 KB
437
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800438#
439# Architectures with an unreliable sched_clock() should select this:
440#
441config HAVE_UNSTABLE_SCHED_CLOCK
442 bool
443
444config GROUP_SCHED
445 bool "Group CPU scheduler"
446 depends on EXPERIMENTAL
447 default n
448 help
449 This feature lets CPU scheduler recognize task groups and control CPU
450 bandwidth allocation to such task groups.
451 In order to create a group from arbitrary set of processes, use
452 CONFIG_CGROUPS. (See Control Group support.)
453
454config FAIR_GROUP_SCHED
455 bool "Group scheduling for SCHED_OTHER"
456 depends on GROUP_SCHED
457 default GROUP_SCHED
458
459config RT_GROUP_SCHED
460 bool "Group scheduling for SCHED_RR/FIFO"
461 depends on EXPERIMENTAL
462 depends on GROUP_SCHED
463 default n
464 help
465 This feature lets you explicitly allocate real CPU bandwidth
466 to users or control groups (depending on the "Basis for grouping tasks"
467 setting below. If enabled, it will also make it impossible to
468 schedule realtime tasks for non-root users until you allocate
469 realtime bandwidth for them.
470 See Documentation/scheduler/sched-rt-group.txt for more information.
471
472choice
473 depends on GROUP_SCHED
474 prompt "Basis for grouping tasks"
475 default USER_SCHED
476
477config USER_SCHED
478 bool "user id"
479 help
480 This option will choose userid as the basis for grouping
481 tasks, thus providing equal CPU bandwidth to each user.
482
483config CGROUP_SCHED
484 bool "Control groups"
485 depends on CGROUPS
486 help
487 This option allows you to create arbitrary task groups
488 using the "cgroup" pseudo filesystem and control
489 the cpu bandwidth allocated to each such task group.
Li Zefan45ce80f2009-01-15 13:50:59 -0800490 Refer to Documentation/cgroups/cgroups.txt for more
491 information on "cgroup" pseudo filesystem.
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800492
493endchoice
494
Li Zefan23964d22009-01-15 13:50:58 -0800495menuconfig CGROUPS
496 boolean "Control Group support"
Paul Menageddbcc7e2007-10-18 23:39:30 -0700497 help
Li Zefan23964d22009-01-15 13:50:58 -0800498 This option adds support for grouping sets of processes together, for
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800499 use with process control subsystems such as Cpusets, CFS, memory
500 controls or device isolation.
501 See
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800502 - Documentation/scheduler/sched-design-CFS.txt (CFS)
Li Zefan45ce80f2009-01-15 13:50:59 -0800503 - Documentation/cgroups/ (features for grouping, isolation
504 and resource control)
Paul Menageddbcc7e2007-10-18 23:39:30 -0700505
506 Say N if unsure.
507
Li Zefan23964d22009-01-15 13:50:58 -0800508if CGROUPS
509
Paul Menage006cb992007-10-18 23:39:43 -0700510config CGROUP_DEBUG
511 bool "Example debug cgroup subsystem"
512 depends on CGROUPS
Paul Menage418d7d82008-04-29 01:00:05 -0700513 default n
Paul Menage006cb992007-10-18 23:39:43 -0700514 help
515 This option enables a simple cgroup subsystem that
516 exports useful debugging information about the cgroups
Li Zefan23964d22009-01-15 13:50:58 -0800517 framework.
Paul Menage006cb992007-10-18 23:39:43 -0700518
Li Zefan23964d22009-01-15 13:50:58 -0800519 Say N if unsure.
Paul Menage006cb992007-10-18 23:39:43 -0700520
Serge E. Hallyn858d72e2007-10-18 23:39:45 -0700521config CGROUP_NS
Li Zefan23964d22009-01-15 13:50:58 -0800522 bool "Namespace cgroup subsystem"
523 depends on CGROUPS
524 help
525 Provides a simple namespace cgroup subsystem to
526 provide hierarchical naming of sets of namespaces,
527 for instance virtual servers and checkpoint/restart
528 jobs.
Serge E. Hallyn858d72e2007-10-18 23:39:45 -0700529
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700530config CGROUP_FREEZER
Li Zefan23964d22009-01-15 13:50:58 -0800531 bool "Freezer cgroup subsystem"
532 depends on CGROUPS
533 help
534 Provides a way to freeze and unfreeze all tasks in a
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700535 cgroup.
536
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700537config CGROUP_DEVICE
538 bool "Device controller for cgroups"
539 depends on CGROUPS && EXPERIMENTAL
540 help
541 Provides a cgroup implementing whitelists for devices which
542 a process in the cgroup can mknod or open.
543
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544config CPUSETS
545 bool "Cpuset support"
Paul Menagedb7f47c2009-04-02 16:57:55 -0700546 depends on CGROUPS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700548 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 allow dynamically partitioning a system into sets of CPUs and
550 Memory Nodes and assigning tasks to run only within those sets.
551 This is primarily useful on large SMP or NUMA systems.
552
553 Say N if unsure.
554
Li Zefan23964d22009-01-15 13:50:58 -0800555config PROC_PID_CPUSET
556 bool "Include legacy /proc/<pid>/cpuset file"
557 depends on CPUSETS
558 default y
559
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100560config CGROUP_CPUACCT
561 bool "Simple CPU accounting cgroup subsystem"
562 depends on CGROUPS
563 help
564 Provides a simple Resource Controller for monitoring the
Li Zefan23964d22009-01-15 13:50:58 -0800565 total CPU consumed by the tasks in a cgroup.
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100566
Pavel Emelianove552b662008-02-07 00:13:49 -0800567config RESOURCE_COUNTERS
568 bool "Resource counters"
569 help
570 This option enables controller independent resource accounting
Li Zefan23964d22009-01-15 13:50:58 -0800571 infrastructure that works with cgroups.
Pavel Emelianove552b662008-02-07 00:13:49 -0800572 depends on CGROUPS
573
Balbir Singh00f0b822008-03-04 14:28:39 -0800574config CGROUP_MEM_RES_CTLR
575 bool "Memory Resource Controller for Control Groups"
576 depends on CGROUPS && RESOURCE_COUNTERS
Balbir Singhcf475ad2008-04-29 01:00:16 -0700577 select MM_OWNER
Balbir Singh00f0b822008-03-04 14:28:39 -0800578 help
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700579 Provides a memory resource controller that manages both anonymous
Thadeu Lima de Souza Cascardo21acb9c2009-02-04 10:12:08 +0100580 memory and page cache. (See Documentation/cgroups/memory.txt)
Balbir Singh00f0b822008-03-04 14:28:39 -0800581
582 Note that setting this option increases fixed memory overhead
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700583 associated with each page of memory in the system. By this,
584 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
585 usage tracking struct at boot. Total amount of this is printed out
586 at boot.
Balbir Singh00f0b822008-03-04 14:28:39 -0800587
588 Only enable when you're ok with these trade offs and really
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700589 sure you need the memory resource controller. Even when you enable
590 this, you can set "cgroup_disable=memory" at your boot option to
591 disable memory resource controller and you can avoid overheads.
Li Zefanc9d54092009-01-07 18:07:35 -0800592 (and lose benefits of memory resource controller)
Balbir Singh00f0b822008-03-04 14:28:39 -0800593
Balbir Singhcf475ad2008-04-29 01:00:16 -0700594 This config option also selects MM_OWNER config option, which
595 could in turn add some fork/exit overhead.
596
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800597config CGROUP_MEM_RES_CTLR_SWAP
598 bool "Memory Resource Controller Swap Extension(EXPERIMENTAL)"
599 depends on CGROUP_MEM_RES_CTLR && SWAP && EXPERIMENTAL
600 help
601 Add swap management feature to memory resource controller. When you
602 enable this, you can limit mem+swap usage per cgroup. In other words,
603 when you disable this, memory resource controller has no cares to
604 usage of swap...a process can exhaust all of the swap. This extension
605 is useful when you want to avoid exhaustion swap but this itself
606 adds more overheads and consumes memory for remembering information.
607 Especially if you use 32bit system or small memory system, please
608 be careful about enabling this. When memory resource controller
609 is disabled by boot option, this will be automatically disabled and
610 there will be no overhead from this. Even when you set this config=y,
611 if boot option "noswapaccount" is set, swap will not be accounted.
KAMEZAWA Hiroyuki627991a2009-04-02 16:57:47 -0700612 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
613 size is 4096bytes, 512k per 1Gbytes of swap.
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800614
Li Zefan23964d22009-01-15 13:50:58 -0800615endif # CGROUPS
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800616
Li Zefan23964d22009-01-15 13:50:58 -0800617config MM_OWNER
618 bool
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800619
Kay Sievers88a22c92006-09-14 11:23:28 +0200620config SYSFS_DEPRECATED
Ingo Molnard47846c2008-03-04 14:54:47 +0100621 bool
622
623config SYSFS_DEPRECATED_V2
Kay Sieversf6ee6492009-04-16 19:56:37 +0200624 bool "remove sysfs features which may confuse old userspace tools"
Randy Dunlap9148fe82007-12-31 10:05:34 -0800625 depends on SYSFS
Kay Sieversf6ee6492009-04-16 19:56:37 +0200626 default n
Ingo Molnard47846c2008-03-04 14:54:47 +0100627 select SYSFS_DEPRECATED
Kay Sievers88a22c92006-09-14 11:23:28 +0200628 help
Kay Sieversfce3e802008-11-01 14:03:00 +0100629 This option switches the layout of sysfs to the deprecated
Kay Sieversf6ee6492009-04-16 19:56:37 +0200630 version. Do not use it on recent distributions.
Kay Sievers88a22c92006-09-14 11:23:28 +0200631
Kay Sieversfce3e802008-11-01 14:03:00 +0100632 The current sysfs layout features a unified device tree at
633 /sys/devices/, which is able to express a hierarchy between
634 class devices. If the deprecated option is set to Y, the
635 unified device tree is split into a bus device tree at
636 /sys/devices/ and several individual class device trees at
637 /sys/class/. The class and bus devices will be connected by
638 "<subsystem>:<name>" and the "device" links. The "block"
639 class devices, will not show up in /sys/class/block/. Some
640 subsystems will suppress the creation of some devices which
641 depend on the unified device tree.
Kay Sievers88a22c92006-09-14 11:23:28 +0200642
Kay Sieversfce3e802008-11-01 14:03:00 +0100643 This option is not a pure compatibility option that can
644 be safely enabled on newer distributions. It will change the
645 layout of sysfs to the non-extensible deprecated version,
646 and disable some features, which can not be exported without
647 confusing older userspace tools. Since 2007/2008 all major
648 distributions do not enable this option, and ship no tools which
649 depend on the deprecated layout or this option.
650
651 If you are using a new kernel on an older distribution, or use
652 older userspace tools, you might need to say Y here. Do not say Y,
653 if the original kernel, that came with your distribution, has
654 this option set to N.
Kay Sievers88a22c92006-09-14 11:23:28 +0200655
Jens Axboeb86ff9812006-03-23 19:56:55 +0100656config RELAY
657 bool "Kernel->user space relay support (formerly relayfs)"
658 help
659 This option enables support for relay interface support in
660 certain file systems (such as debugfs).
661 It is designed to provide an efficient mechanism for tools and
662 facilities to relay large amounts of data from kernel space to
663 user space.
664
665 If unsure, say N.
666
Pavel Emelyanovc5289a692008-02-08 04:18:19 -0800667config NAMESPACES
668 bool "Namespaces support" if EMBEDDED
669 default !EMBEDDED
670 help
671 Provides the way to make tasks work with different objects using
672 the same id. For example same IPC id may refer to different objects
673 or same user id or pid may refer to different tasks when used in
674 different namespaces.
675
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -0800676config UTS_NS
677 bool "UTS namespace"
678 depends on NAMESPACES
679 help
680 In this namespace tasks see different info provided with the
681 uname() system call
682
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800683config IPC_NS
684 bool "IPC namespace"
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700685 depends on NAMESPACES && (SYSVIPC || POSIX_MQUEUE)
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800686 help
687 In this namespace tasks work with IPC ids which correspond to
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700688 different IPC objects in different namespaces.
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800689
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -0800690config USER_NS
691 bool "User namespace (EXPERIMENTAL)"
692 depends on NAMESPACES && EXPERIMENTAL
693 help
694 This allows containers, i.e. vservers, to use user namespaces
695 to provide different user info for different servers.
696 If unsure, say N.
697
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800698config PID_NS
699 bool "PID Namespaces (EXPERIMENTAL)"
700 default n
701 depends on NAMESPACES && EXPERIMENTAL
702 help
Heikki Orsila12d2b8f2008-07-06 15:48:02 +0300703 Support process id namespaces. This allows having multiple
Matt LaPlante692105b2009-01-26 11:12:25 +0100704 processes with the same pid as long as they are in different
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800705 pid namespaces. This is a building block of containers.
706
707 Unless you want to work with an experimental feature
708 say N here.
709
Matt Helsleyd6eb6332009-01-26 12:25:55 -0800710config NET_NS
711 bool "Network namespace"
712 default n
713 depends on NAMESPACES && EXPERIMENTAL && NET
714 help
715 Allow user space to create what appear to be multiple instances
716 of the network stack.
717
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -0800718config BLK_DEV_INITRD
719 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
720 depends on BROKEN || !FRV
721 help
722 The initial RAM filesystem is a ramfs which is loaded by the
723 boot loader (loadlin or lilo) and that is mounted as root
724 before the normal boot procedure. It is typically used to
725 load modules needed to mount the "real" root file system,
726 etc. See <file:Documentation/initrd.txt> for details.
727
728 If RAM disk support (BLK_DEV_RAM) is also included, this
729 also enables initial RAM disk (initrd) support and adds
730 15 Kbytes (more on some other architectures) to the kernel size.
731
732 If unsure say Y.
733
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800734if BLK_DEV_INITRD
735
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200736source "usr/Kconfig"
737
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800738endif
739
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800740config CC_OPTIMIZE_FOR_SIZE
Ingo Molnar96fffeb2008-04-28 01:39:43 +0200741 bool "Optimize for size"
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800742 default y
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800743 help
744 Enabling this option will pass "-Os" instead of "-O2" to gcc
745 resulting in a smaller kernel.
746
jkacur775a7222008-07-16 00:31:16 +0200747 If unsure, say Y.
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800748
Randy Dunlap08470622006-09-30 23:28:13 -0700749config SYSCTL
750 bool
751
Randy Dunlapb943c462009-03-10 12:55:46 -0700752config ANON_INODES
753 bool
754
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755menuconfig EMBEDDED
756 bool "Configure standard kernel features (for small systems)"
757 help
758 This option allows certain base kernel options and settings
759 to be disabled or tweaked. This is for specialized
760 environments which can tolerate a "non-standard" kernel.
761 Only use this if you really know what you are doing.
762
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700763config UID16
764 bool "Enable 16-bit UID system calls" if EMBEDDED
David S. Miller09337f52008-04-26 03:17:12 -0700765 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 -0700766 default y
767 help
768 This enables the legacy 16-bit UID syscall wrappers.
769
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700770config SYSCTL_SYSCALL
Randy Dunlap08470622006-09-30 23:28:13 -0700771 bool "Sysctl syscall support" if EMBEDDED
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800772 default y
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700773 select SYSCTL
774 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800775 sys_sysctl uses binary paths that have been found challenging
776 to properly maintain and use. The interface in /proc/sys
777 using paths with ascii names is now the primary path to this
778 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700779
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800780 Almost nothing using the binary sysctl interface so if you are
781 trying to save some space it is probably safe to disable this,
782 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700783
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800784 If unsure say Y here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700785
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786config KALLSYMS
Jesper Juhl979c6a12006-12-12 19:25:11 +0100787 bool "Load all symbols for debugging/ksymoops" if EMBEDDED
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788 default y
789 help
790 Say Y here to let the kernel print out symbolic crash information and
791 symbolic stack backtraces. This increases the size of the kernel
792 somewhat, as all symbols have to be loaded into the kernel image.
793
794config KALLSYMS_ALL
795 bool "Include all symbols in kallsyms"
796 depends on DEBUG_KERNEL && KALLSYMS
797 help
798 Normally kallsyms only contains the symbols of functions, for nicer
799 OOPS messages. Some debuggers can use kallsyms for other
Jesper Juhlf9f97bc2005-07-20 05:43:05 +0200800 symbols too: say Y here to include all symbols, if you need them
801 and you don't care about adding 300k to the size of your kernel.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802
803 Say N.
804
805config KALLSYMS_EXTRA_PASS
806 bool "Do an extra kallsyms pass"
807 depends on KALLSYMS
808 help
809 If kallsyms is not working correctly, the build will fail with
810 inconsistent kallsyms data. If that occurs, log a bug report and
811 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
812 Always say N here unless you find a bug in kallsyms, which must be
813 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
814 you wait for kallsyms to be fixed.
815
Matt Mackalld59745c2005-05-01 08:59:02 -0700816
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -0800817config HOTPLUG
818 bool "Support for hot-pluggable devices" if EMBEDDED
819 default y
820 help
821 This option is provided for the case where no hotplug or uevent
822 capabilities is wanted by the kernel. You should only consider
823 disabling this option for embedded systems that do not use modules, a
824 dynamic /dev tree, or dynamic device discovery. Just say Y.
825
Matt Mackalld59745c2005-05-01 08:59:02 -0700826config PRINTK
827 default y
828 bool "Enable support for printk" if EMBEDDED
829 help
830 This option enables normal printk support. Removing it
831 eliminates most of the message strings from the kernel image
832 and makes the kernel more or less silent. As this makes it
833 very difficult to diagnose system problems, saying N here is
834 strongly discouraged.
835
Matt Mackallc8538a72005-05-01 08:59:01 -0700836config BUG
837 bool "BUG() support" if EMBEDDED
838 default y
839 help
840 Disabling this option eliminates support for BUG and WARN, reducing
841 the size of your kernel image and potentially quietly ignoring
842 numerous fatal conditions. You should only consider disabling this
843 option for embedded systems with no facilities for reporting errors.
844 Just say Y.
845
Matt Mackall708e9a72006-01-08 01:05:25 -0800846config ELF_CORE
847 default y
848 bool "Enable ELF core dumps" if EMBEDDED
849 help
850 Enable support for generating core dumps. Disabling saves about 4k.
851
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +0200852config PCSPKR_PLATFORM
853 bool "Enable PC-Speaker support" if EMBEDDED
854 depends on ALPHA || X86 || MIPS || PPC_PREP || PPC_CHRP || PPC_PSERIES
855 default y
856 help
857 This option allows to disable the internal PC-Speaker
858 support, saving some memory.
859
Linus Torvalds1da177e2005-04-16 15:20:36 -0700860config BASE_FULL
861 default y
862 bool "Enable full-sized data structures for core" if EMBEDDED
863 help
864 Disabling this option reduces the size of miscellaneous core
865 kernel data structures. This saves memory on small machines,
866 but may reduce performance.
867
868config FUTEX
869 bool "Enable futex support" if EMBEDDED
870 default y
Ingo Molnar23f78d4a2006-06-27 02:54:53 -0700871 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872 help
873 Disabling this option will cause the kernel to be built without
874 support for "fast userspace mutexes". The resulting kernel may not
875 run glibc-based applications correctly.
876
877config EPOLL
878 bool "Enable eventpoll support" if EMBEDDED
879 default y
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700880 select ANON_INODES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700881 help
882 Disabling this option will cause the kernel to be built without
883 support for epoll family of system calls.
884
Davide Libenzifba2afa2007-05-10 22:23:13 -0700885config SIGNALFD
886 bool "Enable signalfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700887 select ANON_INODES
Davide Libenzifba2afa2007-05-10 22:23:13 -0700888 default y
889 help
890 Enable the signalfd() system call that allows to receive signals
891 on a file descriptor.
892
893 If unsure, say Y.
894
Davide Libenzib215e282007-05-10 22:23:16 -0700895config TIMERFD
896 bool "Enable timerfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700897 select ANON_INODES
Davide Libenzib215e282007-05-10 22:23:16 -0700898 default y
899 help
900 Enable the timerfd() system call that allows to receive timer
901 events on a file descriptor.
902
903 If unsure, say Y.
904
Davide Libenzie1ad7462007-05-10 22:23:19 -0700905config EVENTFD
906 bool "Enable eventfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700907 select ANON_INODES
Davide Libenzie1ad7462007-05-10 22:23:19 -0700908 default y
909 help
910 Enable the eventfd() system call that allows to receive both
911 kernel notification (ie. KAIO) or userspace notifications.
912
913 If unsure, say Y.
914
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915config SHMEM
916 bool "Use full shmem filesystem" if EMBEDDED
917 default y
918 depends on MMU
919 help
920 The shmem is an internal filesystem used to manage shared memory.
921 It is backed by swap and manages resource limits. It is also exported
922 to userspace as tmpfs if TMPFS is enabled. Disabling this
923 option replaces shmem and tmpfs with the much simpler ramfs code,
924 which may be appropriate on small systems without swap.
925
Thomas Petazzoniebf3f092008-10-15 22:05:12 -0700926config AIO
927 bool "Enable AIO support" if EMBEDDED
928 default y
929 help
930 This option enables POSIX asynchronous I/O which may by used
931 by some high performance threaded applications. Disabling
932 this option saves about 7k.
933
Thomas Gleixner0793a612008-12-04 20:12:29 +0100934config HAVE_PERF_COUNTERS
935 bool
Mike Frysinger018df722009-06-12 13:17:43 -0400936 help
937 See tools/perf/design.txt for details.
Thomas Gleixner0793a612008-12-04 20:12:29 +0100938
939menu "Performance Counters"
940
941config PERF_COUNTERS
942 bool "Kernel Performance Counters"
943 depends on HAVE_PERF_COUNTERS
Ingo Molnar4c59e462008-12-08 19:38:33 +0100944 select ANON_INODES
Thomas Gleixner0793a612008-12-04 20:12:29 +0100945 help
946 Enable kernel support for performance counter hardware.
947
948 Performance counters are special hardware registers available
949 on most modern CPUs. These registers count the number of certain
950 types of hw events: such as instructions executed, cachemisses
951 suffered, or branches mis-predicted - without slowing down the
952 kernel or applications. These registers can also trigger interrupts
953 when a threshold number of events have passed - and can thus be
954 used to profile the code that runs on that CPU.
955
956 The Linux Performance Counter subsystem provides an abstraction of
957 these hardware capabilities, available via a system call. It
958 provides per task and per CPU counters, and it provides event
959 capabilities on top of those.
960
961 Say Y if unsure.
962
Peter Zijlstrae077df42009-03-19 20:26:17 +0100963config EVENT_PROFILE
964 bool "Tracepoint profile sources"
965 depends on PERF_COUNTERS && EVENT_TRACER
966 default y
967
Thomas Gleixner0793a612008-12-04 20:12:29 +0100968endmenu
969
Christoph Lameterf8891e52006-06-30 01:55:45 -0700970config VM_EVENT_COUNTERS
971 default y
972 bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
973 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -0800974 VM event counters are needed for event counts to be shown.
975 This option allows the disabling of the VM event counters
976 on EMBEDDED systems. /proc/vmstat will only show page counts
977 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -0700978
Thomas Petazzoni3d137312008-08-19 10:28:24 +0200979config PCI_QUIRKS
980 default y
Geert Uytterhoeven61cfc7e2008-10-22 08:53:25 +0200981 bool "Enable PCI quirk workarounds" if EMBEDDED
982 depends on PCI
Thomas Petazzoni3d137312008-08-19 10:28:24 +0200983 help
984 This enables workarounds for various PCI chipset
985 bugs/quirks. Disable this only if your target machine is
986 unaffected by PCI quirks.
987
Christoph Lameter41ecc552007-05-09 02:32:44 -0700988config SLUB_DEBUG
989 default y
990 bool "Enable SLUB debugging support" if EMBEDDED
Christoph Lameterf6acb632008-04-29 16:16:06 -0700991 depends on SLUB && SYSFS
Christoph Lameter41ecc552007-05-09 02:32:44 -0700992 help
993 SLUB has extensive debug support features. Disabling these can
994 result in significant savings in code size. This also disables
995 SLUB sysfs support. /sys/slab will not exist and there will be
996 no support for cache validation etc.
997
Randy Dunlapa9eb5222009-06-05 15:02:47 -0700998config STRIP_ASM_SYMS
999 bool "Strip assembler-generated symbols during link"
1000 default n
1001 help
1002 Strip internal assembler-generated symbols during a link (symbols
1003 that look like '.Lxxx') so they don't pollute the output of
1004 get_wchan() and suchlike.
1005
Randy Dunlapb943c462009-03-10 12:55:46 -07001006config COMPAT_BRK
1007 bool "Disable heap randomization"
1008 default y
1009 help
1010 Randomizing heap placement makes heap exploits harder, but it
1011 also breaks ancient binaries (including anything libc5 based).
1012 This option changes the bootup default to heap randomization
Matt LaPlante692105b2009-01-26 11:12:25 +01001013 disabled, and can be overridden at runtime by setting
Randy Dunlapb943c462009-03-10 12:55:46 -07001014 /proc/sys/kernel/randomize_va_space to 2.
1015
1016 On non-ancient distros (post-2000 ones) N is usually a safe choice.
1017
Christoph Lameter81819f02007-05-06 14:49:36 -07001018choice
1019 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -07001020 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001021 help
1022 This option allows to select a slab allocator.
1023
1024config SLAB
1025 bool "SLAB"
1026 help
1027 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -07001028 well in all environments. It organizes cache hot objects in
Simon Arlott02f56212008-11-05 22:18:19 +00001029 per cpu and per node queues.
Christoph Lameter81819f02007-05-06 14:49:36 -07001030
1031config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001032 bool "SLUB (Unqueued Allocator)"
1033 help
1034 SLUB is a slab allocator that minimizes cache line usage
1035 instead of managing queues of cached objects (SLAB approach).
1036 Per cpu caching is realized using slabs of objects instead
1037 of queues of objects. SLUB can use memory efficiently
Simon Arlott02f56212008-11-05 22:18:19 +00001038 and has enhanced diagnostics. SLUB is the default choice for
1039 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -07001040
1041config SLOB
Paul Mundt84a01c22007-07-15 23:38:24 -07001042 depends on EMBEDDED
Christoph Lameter81819f02007-05-06 14:49:36 -07001043 bool "SLOB (Simple Allocator)"
1044 help
Matt Mackall37291452008-02-04 22:29:38 -08001045 SLOB replaces the stock allocator with a drastically simpler
1046 allocator. SLOB is generally more space efficient but
1047 does not perform as well on large systems.
Christoph Lameter81819f02007-05-06 14:49:36 -07001048
1049endchoice
1050
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001051config PROFILING
1052 bool "Profiling support (EXPERIMENTAL)"
1053 help
1054 Say Y here to enable the extended profiling support mechanisms used
1055 by profilers such as OProfile.
1056
Ingo Molnar5f87f112008-07-23 14:15:22 +02001057#
1058# Place an empty function call at each tracepoint site. Can be
1059# dynamically changed for a probe function.
1060#
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001061config TRACEPOINTS
Ingo Molnar5f87f112008-07-23 14:15:22 +02001062 bool
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001063
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001064config MARKERS
1065 bool "Activate markers"
Frederic Weisbecker91f73f92009-02-20 17:34:06 +01001066 select TRACEPOINTS
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001067 help
1068 Place an empty function call at each marker site. Can be
1069 dynamically changed for a probe function.
1070
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -05001071source "arch/Kconfig"
1072
David Howells07fe7cb2009-04-03 16:42:35 +01001073config SLOW_WORK
1074 default n
David Howells1c2d0082009-04-06 15:47:25 +01001075 bool
David Howells07fe7cb2009-04-03 16:42:35 +01001076 help
1077 The slow work thread pool provides a number of dynamically allocated
1078 threads that can be used by the kernel to perform operations that
1079 take a relatively long time.
1080
1081 An example of this would be CacheFiles doing a path lookup followed
1082 by a series of mkdirs and a create call, all of which have to touch
1083 disk.
1084
David Howells1c2d0082009-04-06 15:47:25 +01001085 See Documentation/slow-work.txt.
1086
Linus Torvalds1da177e2005-04-16 15:20:36 -07001087endmenu # General setup
1088
Dmitry Baryshkovee7e5512008-06-29 14:18:46 +04001089config HAVE_GENERIC_DMA_COHERENT
1090 bool
1091 default n
1092
Linus Torvalds158a9622008-01-02 13:04:48 -08001093config SLABINFO
1094 bool
1095 depends on PROC_FS
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001096 depends on SLAB || SLUB_DEBUG
Linus Torvalds158a9622008-01-02 13:04:48 -08001097 default y
1098
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001099config RT_MUTEXES
1100 boolean
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001101
Linus Torvalds1da177e2005-04-16 15:20:36 -07001102config BASE_SMALL
1103 int
1104 default 0 if BASE_FULL
1105 default 1 if !BASE_FULL
1106
Jan Engelhardt66da5732007-07-15 23:39:29 -07001107menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001108 bool "Enable loadable module support"
1109 help
1110 Kernel modules are small pieces of compiled code which can
1111 be inserted in the running kernel, rather than being
1112 permanently built into the kernel. You use the "modprobe"
1113 tool to add (and sometimes remove) them. If you say Y here,
1114 many parts of the kernel can be built as modules (by
1115 answering M instead of Y where indicated): this is most
1116 useful for infrequently used options which are not required
1117 for booting. For more information, see the man pages for
1118 modprobe, lsmod, modinfo, insmod and rmmod.
1119
1120 If you say Y here, you will need to run "make
1121 modules_install" to put the modules under /lib/modules/
1122 where modprobe can find them (you may need to be root to do
1123 this).
1124
1125 If unsure, say Y.
1126
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001127if MODULES
1128
Linus Torvalds826e4502008-05-04 17:04:16 -07001129config MODULE_FORCE_LOAD
1130 bool "Forced module loading"
Linus Torvalds826e4502008-05-04 17:04:16 -07001131 default n
1132 help
Rusty Russell91e37a72008-05-09 16:25:28 +10001133 Allow loading of modules without version information (ie. modprobe
1134 --force). Forced module loading sets the 'F' (forced) taint flag and
1135 is usually a really bad idea.
Linus Torvalds826e4502008-05-04 17:04:16 -07001136
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137config MODULE_UNLOAD
1138 bool "Module unloading"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001139 help
1140 Without this option you will not be able to unload any
1141 modules (note that some modules may not be unloadable
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001142 anyway), which makes your kernel smaller, faster
1143 and simpler. If unsure, say Y.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001144
1145config MODULE_FORCE_UNLOAD
1146 bool "Forced module unloading"
1147 depends on MODULE_UNLOAD && EXPERIMENTAL
1148 help
1149 This option allows you to force a module to unload, even if the
1150 kernel believes it is unsafe: the kernel will remove the module
1151 without waiting for anyone to stop using it (using the -f option to
1152 rmmod). This is mainly for kernel developers and desperate users.
1153 If unsure, say N.
1154
Linus Torvalds1da177e2005-04-16 15:20:36 -07001155config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +01001156 bool "Module versioning support"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001157 help
1158 Usually, you have to use modules compiled with your kernel.
1159 Saying Y here makes it sometimes possible to use modules
1160 compiled for different kernels, by adding enough information
1161 to the modules to (hopefully) spot any changes which would
1162 make them incompatible with the kernel you are running. If
1163 unsure, say N.
1164
1165config MODULE_SRCVERSION_ALL
1166 bool "Source checksum for all modules"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001167 help
1168 Modules which contain a MODULE_VERSION get an extra "srcversion"
1169 field inserted into their modinfo section, which contains a
1170 sum of the source files which made it. This helps maintainers
1171 see exactly which source was used to build a module (since
1172 others sometimes change the module source without updating
1173 the version). With this option, such a "srcversion" field
1174 will be created for all modules. If unsure, say N.
1175
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001176endif # MODULES
1177
Rusty Russell98a79d62008-12-13 21:19:41 +10301178config INIT_ALL_POSSIBLE
1179 bool
1180 help
1181 Back when each arch used to define their own cpu_online_map and
1182 cpu_possible_map, some of them chose to initialize cpu_possible_map
1183 with all 1s, and others with all 0s. When they were centralised,
1184 it was better to provide this option than to break all the archs
Matt LaPlante692105b2009-01-26 11:12:25 +01001185 and have several arch maintainers pursuing me down dark alleys.
Rusty Russell98a79d62008-12-13 21:19:41 +10301186
Linus Torvalds1da177e2005-04-16 15:20:36 -07001187config STOP_MACHINE
1188 bool
1189 default y
1190 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
1191 help
1192 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001193
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001194source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -07001195
1196config PREEMPT_NOTIFIERS
1197 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +01001198