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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
Al Boldiff0cfc62007-07-31 00:39:23 -070019menu "General setup"
Linus Torvalds1da177e2005-04-16 15:20:36 -070020
21config EXPERIMENTAL
22 bool "Prompt for development and/or incomplete code/drivers"
23 ---help---
24 Some of the various things that Linux supports (such as network
25 drivers, file systems, network protocols, etc.) can be in a state
26 of development where the functionality, stability, or the level of
27 testing is not yet high enough for general use. This is usually
28 known as the "alpha-test" phase among developers. If a feature is
29 currently in alpha-test, then the developers usually discourage
30 uninformed widespread use of this feature by the general public to
31 avoid "Why doesn't this work?" type mail messages. However, active
32 testing and use of these systems is welcomed. Just be aware that it
33 may not meet the normal level of reliability or it may fail to work
34 in some special cases. Detailed bug reports from people familiar
35 with the kernel internals are usually welcomed by the developers
36 (before submitting bug reports, please read the documents
37 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
38 <file:Documentation/BUG-HUNTING>, and
39 <file:Documentation/oops-tracing.txt> in the kernel source).
40
41 This option will also make obsoleted drivers available. These are
42 drivers that have been replaced by something else, and/or are
43 scheduled to be removed in a future kernel release.
44
45 Unless you intend to help test and develop a feature or driver that
46 falls into this category, or you have a situation that requires
47 using these features, you should probably say N here, which will
48 cause the configurator to present you with fewer choices. If
49 you say Y here, you will be offered the choice of using features or
50 drivers that are currently considered to be in the alpha-test phase.
51
Linus Torvalds1da177e2005-04-16 15:20:36 -070052config BROKEN
53 bool
Linus Torvalds1da177e2005-04-16 15:20:36 -070054
55config BROKEN_ON_SMP
56 bool
57 depends on BROKEN || !SMP
58 default y
59
60config LOCK_KERNEL
61 bool
62 depends on SMP || PREEMPT
63 default y
64
65config INIT_ENV_ARG_LIMIT
66 int
Adrian Bunkdd673bc2006-06-30 01:55:51 -070067 default 32 if !UML
68 default 128 if UML
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 help
Randy Dunlap34ad92c2005-10-30 15:01:46 -080070 Maximum of each of the number of arguments and environment
71 variables passed to init from the kernel command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -070072
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
74config LOCALVERSION
75 string "Local version - append to kernel release"
76 help
77 Append an extra string to the end of your kernel version.
78 This will show up when you type uname, for example.
79 The string you set here will be appended after the contents of
80 any files with a filename matching localversion* in your
81 object and source tree, in that order. Your total string can
82 be a maximum of 64 characters.
83
Ryan Andersonaaebf432005-07-31 04:57:49 -040084config LOCALVERSION_AUTO
85 bool "Automatically append version information to the version string"
86 default y
87 help
88 This will try to automatically determine if the current tree is a
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020089 release tree by looking for git tags that belong to the current
90 top of tree revision.
Ryan Andersonaaebf432005-07-31 04:57:49 -040091
92 A string of the format -gxxxxxxxx will be added to the localversion
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020093 if a git-based tree is found. The string generated by this will be
Ryan Andersonaaebf432005-07-31 04:57:49 -040094 appended after any matching localversion* files, and after the value
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020095 set in CONFIG_LOCALVERSION.
Ryan Andersonaaebf432005-07-31 04:57:49 -040096
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020097 (The actual string used here is the first eight characters produced
98 by running the command:
99
100 $ git rev-parse --verify HEAD
101
102 which is done within the script "scripts/setlocalversion".)
Ryan Andersonaaebf432005-07-31 04:57:49 -0400103
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800104config HAVE_KERNEL_GZIP
105 bool
106
107config HAVE_KERNEL_BZIP2
108 bool
109
110config HAVE_KERNEL_LZMA
111 bool
112
Alain Knaff30d65db2009-01-04 22:46:17 +0100113choice
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800114 prompt "Kernel compression mode"
115 default KERNEL_GZIP
116 depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA
117 help
Alain Knaff30d65db2009-01-04 22:46:17 +0100118 The linux kernel is a kind of self-extracting executable.
119 Several compression algorithms are available, which differ
120 in efficiency, compression and decompression speed.
121 Compression speed is only relevant when building a kernel.
122 Decompression speed is relevant at each boot.
123
124 If you have any problems with bzip2 or lzma compressed
125 kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
126 version of this functionality (bzip2 only), for 2.4, was
127 supplied by Christian Ludwig)
128
129 High compression options are mostly useful for users, who
130 are low on disk space (embedded systems), but for whom ram
131 size matters less.
132
133 If in doubt, select 'gzip'
134
135config KERNEL_GZIP
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800136 bool "Gzip"
137 depends on HAVE_KERNEL_GZIP
138 help
139 The old and tried gzip compression. Its compression ratio is
140 the poorest among the 3 choices; however its speed (both
141 compression and decompression) is the fastest.
Alain Knaff30d65db2009-01-04 22:46:17 +0100142
143config KERNEL_BZIP2
144 bool "Bzip2"
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800145 depends on HAVE_KERNEL_BZIP2
Alain Knaff30d65db2009-01-04 22:46:17 +0100146 help
147 Its compression ratio and speed is intermediate.
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800148 Decompression speed is slowest among the three. The kernel
149 size is about 10% smaller with bzip2, in comparison to gzip.
150 Bzip2 uses a large amount of memory. For modern kernels you
151 will need at least 8MB RAM or more for booting.
Alain Knaff30d65db2009-01-04 22:46:17 +0100152
153config KERNEL_LZMA
H. Peter Anvin2e9f3bd2009-01-04 15:41:25 -0800154 bool "LZMA"
155 depends on HAVE_KERNEL_LZMA
156 help
157 The most recent compression algorithm.
158 Its ratio is best, decompression speed is between the other
159 two. Compression is slowest. The kernel size is about 33%
160 smaller with LZMA in comparison to gzip.
Alain Knaff30d65db2009-01-04 22:46:17 +0100161
162endchoice
163
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164config SWAP
165 bool "Support for paging of anonymous memory (swap)"
David Howells93614012006-09-30 20:45:40 +0200166 depends on MMU && BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167 default y
168 help
169 This option allows you to choose whether you want to have support
Jesper Juhl92c35042006-01-15 02:40:08 +0100170 for so called swap devices or swap files in your kernel that are
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171 used to provide more virtual memory than the actual RAM present
172 in your computer. If unsure say Y.
173
174config SYSVIPC
175 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 ---help---
177 Inter Process Communication is a suite of library functions and
178 system calls which let processes (running programs) synchronize and
179 exchange information. It is generally considered to be a good thing,
180 and some programs won't run unless you say Y here. In particular, if
181 you want to run the DOS emulator dosemu under Linux (read the
182 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
183 you'll need to say Y here.
184
185 You can find documentation about IPC with "info ipc" and also in
186 section 6.4 of the Linux Programmer's Guide, available from
187 <http://www.tldp.org/guides.html>.
188
Eric W. Biedermana5494dc2007-02-14 00:34:06 -0800189config SYSVIPC_SYSCTL
190 bool
191 depends on SYSVIPC
192 depends on SYSCTL
193 default y
194
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195config POSIX_MQUEUE
196 bool "POSIX Message Queues"
197 depends on NET && EXPERIMENTAL
198 ---help---
199 POSIX variant of message queues is a part of IPC. In POSIX message
200 queues every message has a priority which decides about succession
201 of receiving it by a process. If you want to compile and run
202 programs written e.g. for Solaris with use of its POSIX message
Robert P. J. Dayb0e37652007-05-09 07:25:13 +0200203 queues (functions mq_*) say Y here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204
205 POSIX message queues are visible as a filesystem called 'mqueue'
206 and can be mounted somewhere if you want to do filesystem
207 operations on message queues.
208
209 If unsure, say Y.
210
Serge E. Hallynbdc8e5f2009-04-06 19:01:11 -0700211config POSIX_MQUEUE_SYSCTL
212 bool
213 depends on POSIX_MQUEUE
214 depends on SYSCTL
215 default y
216
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217config BSD_PROCESS_ACCT
218 bool "BSD Process Accounting"
219 help
220 If you say Y here, a user level program will be able to instruct the
221 kernel (via a special system call) to write process accounting
222 information to a file: whenever a process exits, information about
223 that process will be appended to the file by the kernel. The
224 information includes things such as creation time, owning user,
225 command name, memory usage, controlling terminal etc. (the complete
226 list is in the struct acct in <file:include/linux/acct.h>). It is
227 up to the user level program to do useful things with this
228 information. This is generally a good idea, so say Y.
229
230config BSD_PROCESS_ACCT_V3
231 bool "BSD Process Accounting version 3 file format"
232 depends on BSD_PROCESS_ACCT
233 default n
234 help
235 If you say Y here, the process accounting information is written
236 in a new file format that also logs the process IDs of each
237 process and it's parent. Note that this file format is incompatible
238 with previous v0/v1/v2 file formats, so you will need updated tools
239 for processing it. A preliminary version of these tools is available
S.Çağlar Onur37a4c942008-06-18 11:45:13 +0300240 at <http://www.gnu.org/software/acct/>.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241
Shailabh Nagarc7572492006-07-14 00:24:40 -0700242config TASKSTATS
243 bool "Export task/process statistics through netlink (EXPERIMENTAL)"
244 depends on NET
245 default n
246 help
247 Export selected statistics for tasks/processes through the
248 generic netlink interface. Unlike BSD process accounting, the
249 statistics are available during the lifetime of tasks/processes as
250 responses to commands. Like BSD accounting, they are sent to user
251 space on task exit.
252
253 Say N if unsure.
254
Shailabh Nagarca74e922006-07-14 00:24:36 -0700255config TASK_DELAY_ACCT
256 bool "Enable per-task delay accounting (EXPERIMENTAL)"
Shailabh Nagar6f449932006-07-14 00:24:41 -0700257 depends on TASKSTATS
Shailabh Nagarca74e922006-07-14 00:24:36 -0700258 help
259 Collect information on time spent by a task waiting for system
260 resources like cpu, synchronous block I/O completion and swapping
261 in pages. Such statistics can help in setting a task's priorities
262 relative to other tasks for cpu, io, rss limits etc.
263
264 Say N if unsure.
265
Alexey Dobriyan18f705f2007-02-10 01:46:44 -0800266config TASK_XACCT
267 bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
268 depends on TASKSTATS
269 help
270 Collect extended task accounting data and send the data
271 to userland for processing over the taskstats interface.
272
273 Say N if unsure.
274
275config TASK_IO_ACCOUNTING
276 bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
277 depends on TASK_XACCT
278 help
279 Collect information on the number of bytes of storage I/O which this
280 task has caused.
281
282 Say N if unsure.
283
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284config AUDIT
285 bool "Auditing support"
Chris Wright804a6a492005-05-11 10:52:45 +0100286 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 help
288 Enable auditing infrastructure that can be used with another
289 kernel subsystem, such as SELinux (which requires this for
290 logging of avc messages output). Does not do system-call
291 auditing without CONFIG_AUDITSYSCALL.
292
293config AUDITSYSCALL
294 bool "Enable system-call auditing support"
Yuichi Nakamura1322b9d2007-11-10 19:21:34 +0900295 depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64|| SUPERH)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296 default y if SECURITY_SELINUX
297 help
298 Enable low-overhead system-call auditing infrastructure that
299 can be used independently or with another kernel subsystem,
Amy Griffisf368c07d2006-04-07 16:55:56 -0400300 such as SELinux. To use audit's filesystem watch feature, please
301 ensure that INOTIFY is configured.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302
Al Viro74c3cbe2007-07-22 08:04:18 -0400303config AUDIT_TREE
304 def_bool y
305 depends on AUDITSYSCALL && INOTIFY
306
Mike Travisc903ff82009-01-15 12:28:29 -0800307menu "RCU Subsystem"
308
309choice
310 prompt "RCU Implementation"
311 default CLASSIC_RCU
312
313config CLASSIC_RCU
314 bool "Classic RCU"
315 help
316 This option selects the classic RCU implementation that is
317 designed for best read-side performance on non-realtime
318 systems.
319
320 Select this option if you are unsure.
321
322config TREE_RCU
323 bool "Tree-based hierarchical RCU"
324 help
325 This option selects the RCU implementation that is
326 designed for very large SMP system with hundreds or
327 thousands of CPUs.
328
329config PREEMPT_RCU
330 bool "Preemptible RCU"
331 depends on PREEMPT
332 help
333 This option reduces the latency of the kernel by making certain
334 RCU sections preemptible. Normally RCU code is non-preemptible, if
335 this option is selected then read-only RCU sections become
336 preemptible. This helps latency, but may expose bugs due to
337 now-naive assumptions about each RCU read-side critical section
338 remaining on a given CPU through its execution.
339
340endchoice
341
342config RCU_TRACE
343 bool "Enable tracing for RCU"
344 depends on TREE_RCU || PREEMPT_RCU
345 help
346 This option provides tracing in RCU which presents stats
347 in debugfs for debugging RCU implementation.
348
349 Say Y here if you want to enable RCU tracing
350 Say N if you are unsure.
351
352config RCU_FANOUT
353 int "Tree-based hierarchical RCU fanout value"
354 range 2 64 if 64BIT
355 range 2 32 if !64BIT
356 depends on TREE_RCU
357 default 64 if 64BIT
358 default 32 if !64BIT
359 help
360 This option controls the fanout of hierarchical implementations
361 of RCU, allowing RCU to work efficiently on machines with
362 large numbers of CPUs. This value must be at least the cube
363 root of NR_CPUS, which allows NR_CPUS up to 32,768 for 32-bit
364 systems and up to 262,144 for 64-bit systems.
365
366 Select a specific number if testing RCU itself.
367 Take the default if unsure.
368
369config RCU_FANOUT_EXACT
370 bool "Disable tree-based hierarchical RCU auto-balancing"
371 depends on TREE_RCU
372 default n
373 help
374 This option forces use of the exact RCU_FANOUT value specified,
375 regardless of imbalances in the hierarchy. This is useful for
376 testing RCU itself, and might one day be useful on systems with
377 strong NUMA behavior.
378
379 Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
380
381 Say N if unsure.
382
383config TREE_RCU_TRACE
384 def_bool RCU_TRACE && TREE_RCU
385 select DEBUG_FS
386 help
387 This option provides tracing for the TREE_RCU implementation,
388 permitting Makefile to trivially select kernel/rcutree_trace.c.
389
390config PREEMPT_RCU_TRACE
391 def_bool RCU_TRACE && PREEMPT_RCU
392 select DEBUG_FS
393 help
394 This option provides tracing for the PREEMPT_RCU implementation,
395 permitting Makefile to trivially select kernel/rcupreempt_trace.c.
396
397endmenu # "RCU Subsystem"
398
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700400 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401 ---help---
402 This option enables the complete Linux kernel ".config" file
403 contents to be saved in the kernel. It provides documentation
404 of which kernel options are used in a running kernel or in an
405 on-disk kernel. This information can be extracted from the kernel
406 image file with the script scripts/extract-ikconfig and used as
407 input to rebuild the current kernel or to build another kernel.
408 It can also be extracted from a running kernel by reading
409 /proc/config.gz if enabled (below).
410
411config IKCONFIG_PROC
412 bool "Enable access to .config through /proc/config.gz"
413 depends on IKCONFIG && PROC_FS
414 ---help---
415 This option enables access to the kernel configuration file
416 through /proc/config.gz.
417
Alistair John Strachan794543a2007-05-08 00:31:15 -0700418config LOG_BUF_SHIFT
419 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
420 range 12 21
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700421 default 17
Alistair John Strachan794543a2007-05-08 00:31:15 -0700422 help
423 Select kernel log buffer size as a power of 2.
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700424 Examples:
425 17 => 128 KB
426 16 => 64 KB
427 15 => 32 KB
428 14 => 16 KB
Alistair John Strachan794543a2007-05-08 00:31:15 -0700429 13 => 8 KB
430 12 => 4 KB
431
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800432#
433# Architectures with an unreliable sched_clock() should select this:
434#
435config HAVE_UNSTABLE_SCHED_CLOCK
436 bool
437
438config GROUP_SCHED
439 bool "Group CPU scheduler"
440 depends on EXPERIMENTAL
441 default n
442 help
443 This feature lets CPU scheduler recognize task groups and control CPU
444 bandwidth allocation to such task groups.
445 In order to create a group from arbitrary set of processes, use
446 CONFIG_CGROUPS. (See Control Group support.)
447
448config FAIR_GROUP_SCHED
449 bool "Group scheduling for SCHED_OTHER"
450 depends on GROUP_SCHED
451 default GROUP_SCHED
452
453config RT_GROUP_SCHED
454 bool "Group scheduling for SCHED_RR/FIFO"
455 depends on EXPERIMENTAL
456 depends on GROUP_SCHED
457 default n
458 help
459 This feature lets you explicitly allocate real CPU bandwidth
460 to users or control groups (depending on the "Basis for grouping tasks"
461 setting below. If enabled, it will also make it impossible to
462 schedule realtime tasks for non-root users until you allocate
463 realtime bandwidth for them.
464 See Documentation/scheduler/sched-rt-group.txt for more information.
465
466choice
467 depends on GROUP_SCHED
468 prompt "Basis for grouping tasks"
469 default USER_SCHED
470
471config USER_SCHED
472 bool "user id"
473 help
474 This option will choose userid as the basis for grouping
475 tasks, thus providing equal CPU bandwidth to each user.
476
477config CGROUP_SCHED
478 bool "Control groups"
479 depends on CGROUPS
480 help
481 This option allows you to create arbitrary task groups
482 using the "cgroup" pseudo filesystem and control
483 the cpu bandwidth allocated to each such task group.
Li Zefan45ce80f2009-01-15 13:50:59 -0800484 Refer to Documentation/cgroups/cgroups.txt for more
485 information on "cgroup" pseudo filesystem.
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800486
487endchoice
488
Li Zefan23964d22009-01-15 13:50:58 -0800489menuconfig CGROUPS
490 boolean "Control Group support"
Paul Menageddbcc7e2007-10-18 23:39:30 -0700491 help
Li Zefan23964d22009-01-15 13:50:58 -0800492 This option adds support for grouping sets of processes together, for
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800493 use with process control subsystems such as Cpusets, CFS, memory
494 controls or device isolation.
495 See
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800496 - Documentation/scheduler/sched-design-CFS.txt (CFS)
Li Zefan45ce80f2009-01-15 13:50:59 -0800497 - Documentation/cgroups/ (features for grouping, isolation
498 and resource control)
Paul Menageddbcc7e2007-10-18 23:39:30 -0700499
500 Say N if unsure.
501
Li Zefan23964d22009-01-15 13:50:58 -0800502if CGROUPS
503
Paul Menage006cb992007-10-18 23:39:43 -0700504config CGROUP_DEBUG
505 bool "Example debug cgroup subsystem"
506 depends on CGROUPS
Paul Menage418d7d82008-04-29 01:00:05 -0700507 default n
Paul Menage006cb992007-10-18 23:39:43 -0700508 help
509 This option enables a simple cgroup subsystem that
510 exports useful debugging information about the cgroups
Li Zefan23964d22009-01-15 13:50:58 -0800511 framework.
Paul Menage006cb992007-10-18 23:39:43 -0700512
Li Zefan23964d22009-01-15 13:50:58 -0800513 Say N if unsure.
Paul Menage006cb992007-10-18 23:39:43 -0700514
Serge E. Hallyn858d72e2007-10-18 23:39:45 -0700515config CGROUP_NS
Li Zefan23964d22009-01-15 13:50:58 -0800516 bool "Namespace cgroup subsystem"
517 depends on CGROUPS
518 help
519 Provides a simple namespace cgroup subsystem to
520 provide hierarchical naming of sets of namespaces,
521 for instance virtual servers and checkpoint/restart
522 jobs.
Serge E. Hallyn858d72e2007-10-18 23:39:45 -0700523
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700524config CGROUP_FREEZER
Li Zefan23964d22009-01-15 13:50:58 -0800525 bool "Freezer cgroup subsystem"
526 depends on CGROUPS
527 help
528 Provides a way to freeze and unfreeze all tasks in a
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700529 cgroup.
530
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700531config CGROUP_DEVICE
532 bool "Device controller for cgroups"
533 depends on CGROUPS && EXPERIMENTAL
534 help
535 Provides a cgroup implementing whitelists for devices which
536 a process in the cgroup can mknod or open.
537
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538config CPUSETS
539 bool "Cpuset support"
Paul Menagedb7f47c2009-04-02 16:57:55 -0700540 depends on CGROUPS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700542 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 allow dynamically partitioning a system into sets of CPUs and
544 Memory Nodes and assigning tasks to run only within those sets.
545 This is primarily useful on large SMP or NUMA systems.
546
547 Say N if unsure.
548
Li Zefan23964d22009-01-15 13:50:58 -0800549config PROC_PID_CPUSET
550 bool "Include legacy /proc/<pid>/cpuset file"
551 depends on CPUSETS
552 default y
553
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100554config CGROUP_CPUACCT
555 bool "Simple CPU accounting cgroup subsystem"
556 depends on CGROUPS
557 help
558 Provides a simple Resource Controller for monitoring the
Li Zefan23964d22009-01-15 13:50:58 -0800559 total CPU consumed by the tasks in a cgroup.
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100560
Pavel Emelianove552b662008-02-07 00:13:49 -0800561config RESOURCE_COUNTERS
562 bool "Resource counters"
563 help
564 This option enables controller independent resource accounting
Li Zefan23964d22009-01-15 13:50:58 -0800565 infrastructure that works with cgroups.
Pavel Emelianove552b662008-02-07 00:13:49 -0800566 depends on CGROUPS
567
Balbir Singh00f0b822008-03-04 14:28:39 -0800568config CGROUP_MEM_RES_CTLR
569 bool "Memory Resource Controller for Control Groups"
570 depends on CGROUPS && RESOURCE_COUNTERS
Balbir Singhcf475ad2008-04-29 01:00:16 -0700571 select MM_OWNER
Balbir Singh00f0b822008-03-04 14:28:39 -0800572 help
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700573 Provides a memory resource controller that manages both anonymous
Thadeu Lima de Souza Cascardo21acb9c2009-02-04 10:12:08 +0100574 memory and page cache. (See Documentation/cgroups/memory.txt)
Balbir Singh00f0b822008-03-04 14:28:39 -0800575
576 Note that setting this option increases fixed memory overhead
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700577 associated with each page of memory in the system. By this,
578 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
579 usage tracking struct at boot. Total amount of this is printed out
580 at boot.
Balbir Singh00f0b822008-03-04 14:28:39 -0800581
582 Only enable when you're ok with these trade offs and really
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700583 sure you need the memory resource controller. Even when you enable
584 this, you can set "cgroup_disable=memory" at your boot option to
585 disable memory resource controller and you can avoid overheads.
Li Zefanc9d54092009-01-07 18:07:35 -0800586 (and lose benefits of memory resource controller)
Balbir Singh00f0b822008-03-04 14:28:39 -0800587
Balbir Singhcf475ad2008-04-29 01:00:16 -0700588 This config option also selects MM_OWNER config option, which
589 could in turn add some fork/exit overhead.
590
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800591config CGROUP_MEM_RES_CTLR_SWAP
592 bool "Memory Resource Controller Swap Extension(EXPERIMENTAL)"
593 depends on CGROUP_MEM_RES_CTLR && SWAP && EXPERIMENTAL
594 help
595 Add swap management feature to memory resource controller. When you
596 enable this, you can limit mem+swap usage per cgroup. In other words,
597 when you disable this, memory resource controller has no cares to
598 usage of swap...a process can exhaust all of the swap. This extension
599 is useful when you want to avoid exhaustion swap but this itself
600 adds more overheads and consumes memory for remembering information.
601 Especially if you use 32bit system or small memory system, please
602 be careful about enabling this. When memory resource controller
603 is disabled by boot option, this will be automatically disabled and
604 there will be no overhead from this. Even when you set this config=y,
605 if boot option "noswapaccount" is set, swap will not be accounted.
KAMEZAWA Hiroyuki627991a2009-04-02 16:57:47 -0700606 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
607 size is 4096bytes, 512k per 1Gbytes of swap.
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800608
Li Zefan23964d22009-01-15 13:50:58 -0800609endif # CGROUPS
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800610
Li Zefan23964d22009-01-15 13:50:58 -0800611config MM_OWNER
612 bool
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800613
Kay Sievers88a22c92006-09-14 11:23:28 +0200614config SYSFS_DEPRECATED
Ingo Molnard47846c2008-03-04 14:54:47 +0100615 bool
616
617config SYSFS_DEPRECATED_V2
Kay Sieversfce3e802008-11-01 14:03:00 +0100618 bool "Create deprecated sysfs layout for older userspace tools"
Randy Dunlap9148fe82007-12-31 10:05:34 -0800619 depends on SYSFS
Kay Sievers88a22c92006-09-14 11:23:28 +0200620 default y
Ingo Molnard47846c2008-03-04 14:54:47 +0100621 select SYSFS_DEPRECATED
Kay Sievers88a22c92006-09-14 11:23:28 +0200622 help
Kay Sieversfce3e802008-11-01 14:03:00 +0100623 This option switches the layout of sysfs to the deprecated
624 version.
Kay Sievers88a22c92006-09-14 11:23:28 +0200625
Kay Sieversfce3e802008-11-01 14:03:00 +0100626 The current sysfs layout features a unified device tree at
627 /sys/devices/, which is able to express a hierarchy between
628 class devices. If the deprecated option is set to Y, the
629 unified device tree is split into a bus device tree at
630 /sys/devices/ and several individual class device trees at
631 /sys/class/. The class and bus devices will be connected by
632 "<subsystem>:<name>" and the "device" links. The "block"
633 class devices, will not show up in /sys/class/block/. Some
634 subsystems will suppress the creation of some devices which
635 depend on the unified device tree.
Kay Sievers88a22c92006-09-14 11:23:28 +0200636
Kay Sieversfce3e802008-11-01 14:03:00 +0100637 This option is not a pure compatibility option that can
638 be safely enabled on newer distributions. It will change the
639 layout of sysfs to the non-extensible deprecated version,
640 and disable some features, which can not be exported without
641 confusing older userspace tools. Since 2007/2008 all major
642 distributions do not enable this option, and ship no tools which
643 depend on the deprecated layout or this option.
644
645 If you are using a new kernel on an older distribution, or use
646 older userspace tools, you might need to say Y here. Do not say Y,
647 if the original kernel, that came with your distribution, has
648 this option set to N.
Kay Sievers88a22c92006-09-14 11:23:28 +0200649
Jens Axboeb86ff9812006-03-23 19:56:55 +0100650config RELAY
651 bool "Kernel->user space relay support (formerly relayfs)"
652 help
653 This option enables support for relay interface support in
654 certain file systems (such as debugfs).
655 It is designed to provide an efficient mechanism for tools and
656 facilities to relay large amounts of data from kernel space to
657 user space.
658
659 If unsure, say N.
660
Pavel Emelyanovc5289a62008-02-08 04:18:19 -0800661config NAMESPACES
662 bool "Namespaces support" if EMBEDDED
663 default !EMBEDDED
664 help
665 Provides the way to make tasks work with different objects using
666 the same id. For example same IPC id may refer to different objects
667 or same user id or pid may refer to different tasks when used in
668 different namespaces.
669
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -0800670config UTS_NS
671 bool "UTS namespace"
672 depends on NAMESPACES
673 help
674 In this namespace tasks see different info provided with the
675 uname() system call
676
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800677config IPC_NS
678 bool "IPC namespace"
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700679 depends on NAMESPACES && (SYSVIPC || POSIX_MQUEUE)
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800680 help
681 In this namespace tasks work with IPC ids which correspond to
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700682 different IPC objects in different namespaces.
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800683
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -0800684config USER_NS
685 bool "User namespace (EXPERIMENTAL)"
686 depends on NAMESPACES && EXPERIMENTAL
687 help
688 This allows containers, i.e. vservers, to use user namespaces
689 to provide different user info for different servers.
690 If unsure, say N.
691
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800692config PID_NS
693 bool "PID Namespaces (EXPERIMENTAL)"
694 default n
695 depends on NAMESPACES && EXPERIMENTAL
696 help
Heikki Orsila12d2b8f2008-07-06 15:48:02 +0300697 Support process id namespaces. This allows having multiple
Matt LaPlante692105b2009-01-26 11:12:25 +0100698 processes with the same pid as long as they are in different
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800699 pid namespaces. This is a building block of containers.
700
701 Unless you want to work with an experimental feature
702 say N here.
703
Matt Helsleyd6eb6332009-01-26 12:25:55 -0800704config NET_NS
705 bool "Network namespace"
706 default n
707 depends on NAMESPACES && EXPERIMENTAL && NET
708 help
709 Allow user space to create what appear to be multiple instances
710 of the network stack.
711
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -0800712config BLK_DEV_INITRD
713 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
714 depends on BROKEN || !FRV
715 help
716 The initial RAM filesystem is a ramfs which is loaded by the
717 boot loader (loadlin or lilo) and that is mounted as root
718 before the normal boot procedure. It is typically used to
719 load modules needed to mount the "real" root file system,
720 etc. See <file:Documentation/initrd.txt> for details.
721
722 If RAM disk support (BLK_DEV_RAM) is also included, this
723 also enables initial RAM disk (initrd) support and adds
724 15 Kbytes (more on some other architectures) to the kernel size.
725
726 If unsure say Y.
727
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800728if BLK_DEV_INITRD
729
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200730source "usr/Kconfig"
731
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800732endif
733
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800734config CC_OPTIMIZE_FOR_SIZE
Ingo Molnar96fffeb2008-04-28 01:39:43 +0200735 bool "Optimize for size"
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800736 default y
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800737 help
738 Enabling this option will pass "-Os" instead of "-O2" to gcc
739 resulting in a smaller kernel.
740
jkacur775a7222008-07-16 00:31:16 +0200741 If unsure, say Y.
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800742
Randy Dunlap08470622006-09-30 23:28:13 -0700743config SYSCTL
744 bool
745
Randy Dunlapb943c462009-03-10 12:55:46 -0700746config ANON_INODES
747 bool
748
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749menuconfig EMBEDDED
750 bool "Configure standard kernel features (for small systems)"
751 help
752 This option allows certain base kernel options and settings
753 to be disabled or tweaked. This is for specialized
754 environments which can tolerate a "non-standard" kernel.
755 Only use this if you really know what you are doing.
756
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700757config UID16
758 bool "Enable 16-bit UID system calls" if EMBEDDED
David S. Miller09337f52008-04-26 03:17:12 -0700759 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 -0700760 default y
761 help
762 This enables the legacy 16-bit UID syscall wrappers.
763
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700764config SYSCTL_SYSCALL
Randy Dunlap08470622006-09-30 23:28:13 -0700765 bool "Sysctl syscall support" if EMBEDDED
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800766 default y
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700767 select SYSCTL
768 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800769 sys_sysctl uses binary paths that have been found challenging
770 to properly maintain and use. The interface in /proc/sys
771 using paths with ascii names is now the primary path to this
772 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700773
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800774 Almost nothing using the binary sysctl interface so if you are
775 trying to save some space it is probably safe to disable this,
776 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700777
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800778 If unsure say Y here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700779
Linus Torvalds1da177e2005-04-16 15:20:36 -0700780config KALLSYMS
Jesper Juhl979c6a12006-12-12 19:25:11 +0100781 bool "Load all symbols for debugging/ksymoops" if EMBEDDED
Linus Torvalds1da177e2005-04-16 15:20:36 -0700782 default y
783 help
784 Say Y here to let the kernel print out symbolic crash information and
785 symbolic stack backtraces. This increases the size of the kernel
786 somewhat, as all symbols have to be loaded into the kernel image.
787
788config KALLSYMS_ALL
789 bool "Include all symbols in kallsyms"
790 depends on DEBUG_KERNEL && KALLSYMS
791 help
792 Normally kallsyms only contains the symbols of functions, for nicer
793 OOPS messages. Some debuggers can use kallsyms for other
Jesper Juhlf9f97bc2005-07-20 05:43:05 +0200794 symbols too: say Y here to include all symbols, if you need them
795 and you don't care about adding 300k to the size of your kernel.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796
797 Say N.
798
799config KALLSYMS_EXTRA_PASS
800 bool "Do an extra kallsyms pass"
801 depends on KALLSYMS
802 help
803 If kallsyms is not working correctly, the build will fail with
804 inconsistent kallsyms data. If that occurs, log a bug report and
805 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
806 Always say N here unless you find a bug in kallsyms, which must be
807 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
808 you wait for kallsyms to be fixed.
809
Matt Mackalld59745c2005-05-01 08:59:02 -0700810
David Howells5d7d18f2009-03-04 11:59:07 -0800811config STRIP_ASM_SYMS
812 bool "Strip assembler-generated symbols during link"
813 default n
814 help
815 Strip internal assembler-generated symbols during a link (symbols
816 that look like '.Lxxx') so they don't pollute the output of
817 get_wchan() and suchlike.
818
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -0800819config HOTPLUG
820 bool "Support for hot-pluggable devices" if EMBEDDED
821 default y
822 help
823 This option is provided for the case where no hotplug or uevent
824 capabilities is wanted by the kernel. You should only consider
825 disabling this option for embedded systems that do not use modules, a
826 dynamic /dev tree, or dynamic device discovery. Just say Y.
827
Matt Mackalld59745c2005-05-01 08:59:02 -0700828config PRINTK
829 default y
830 bool "Enable support for printk" if EMBEDDED
831 help
832 This option enables normal printk support. Removing it
833 eliminates most of the message strings from the kernel image
834 and makes the kernel more or less silent. As this makes it
835 very difficult to diagnose system problems, saying N here is
836 strongly discouraged.
837
Matt Mackallc8538a72005-05-01 08:59:01 -0700838config BUG
839 bool "BUG() support" if EMBEDDED
840 default y
841 help
842 Disabling this option eliminates support for BUG and WARN, reducing
843 the size of your kernel image and potentially quietly ignoring
844 numerous fatal conditions. You should only consider disabling this
845 option for embedded systems with no facilities for reporting errors.
846 Just say Y.
847
Matt Mackall708e9a72006-01-08 01:05:25 -0800848config ELF_CORE
849 default y
850 bool "Enable ELF core dumps" if EMBEDDED
851 help
852 Enable support for generating core dumps. Disabling saves about 4k.
853
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +0200854config PCSPKR_PLATFORM
855 bool "Enable PC-Speaker support" if EMBEDDED
856 depends on ALPHA || X86 || MIPS || PPC_PREP || PPC_CHRP || PPC_PSERIES
857 default y
858 help
859 This option allows to disable the internal PC-Speaker
860 support, saving some memory.
861
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862config BASE_FULL
863 default y
864 bool "Enable full-sized data structures for core" if EMBEDDED
865 help
866 Disabling this option reduces the size of miscellaneous core
867 kernel data structures. This saves memory on small machines,
868 but may reduce performance.
869
870config FUTEX
871 bool "Enable futex support" if EMBEDDED
872 default y
Ingo Molnar23f78d4a2006-06-27 02:54:53 -0700873 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874 help
875 Disabling this option will cause the kernel to be built without
876 support for "fast userspace mutexes". The resulting kernel may not
877 run glibc-based applications correctly.
878
879config EPOLL
880 bool "Enable eventpoll support" if EMBEDDED
881 default y
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700882 select ANON_INODES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883 help
884 Disabling this option will cause the kernel to be built without
885 support for epoll family of system calls.
886
Davide Libenzifba2afa2007-05-10 22:23:13 -0700887config SIGNALFD
888 bool "Enable signalfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700889 select ANON_INODES
Davide Libenzifba2afa2007-05-10 22:23:13 -0700890 default y
891 help
892 Enable the signalfd() system call that allows to receive signals
893 on a file descriptor.
894
895 If unsure, say Y.
896
Davide Libenzib215e282007-05-10 22:23:16 -0700897config TIMERFD
898 bool "Enable timerfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700899 select ANON_INODES
Davide Libenzib215e282007-05-10 22:23:16 -0700900 default y
901 help
902 Enable the timerfd() system call that allows to receive timer
903 events on a file descriptor.
904
905 If unsure, say Y.
906
Davide Libenzie1ad7462007-05-10 22:23:19 -0700907config EVENTFD
908 bool "Enable eventfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700909 select ANON_INODES
Davide Libenzie1ad7462007-05-10 22:23:19 -0700910 default y
911 help
912 Enable the eventfd() system call that allows to receive both
913 kernel notification (ie. KAIO) or userspace notifications.
914
915 If unsure, say Y.
916
Linus Torvalds1da177e2005-04-16 15:20:36 -0700917config SHMEM
918 bool "Use full shmem filesystem" if EMBEDDED
919 default y
920 depends on MMU
921 help
922 The shmem is an internal filesystem used to manage shared memory.
923 It is backed by swap and manages resource limits. It is also exported
924 to userspace as tmpfs if TMPFS is enabled. Disabling this
925 option replaces shmem and tmpfs with the much simpler ramfs code,
926 which may be appropriate on small systems without swap.
927
Thomas Petazzoniebf3f092008-10-15 22:05:12 -0700928config AIO
929 bool "Enable AIO support" if EMBEDDED
930 default y
931 help
932 This option enables POSIX asynchronous I/O which may by used
933 by some high performance threaded applications. Disabling
934 this option saves about 7k.
935
Thomas Gleixner0793a612008-12-04 20:12:29 +0100936config HAVE_PERF_COUNTERS
937 bool
938
939menu "Performance Counters"
940
941config PERF_COUNTERS
942 bool "Kernel Performance Counters"
943 depends on HAVE_PERF_COUNTERS
944 default y
Ingo Molnar4c59e462008-12-08 19:38:33 +0100945 select ANON_INODES
Thomas Gleixner0793a612008-12-04 20:12:29 +0100946 help
947 Enable kernel support for performance counter hardware.
948
949 Performance counters are special hardware registers available
950 on most modern CPUs. These registers count the number of certain
951 types of hw events: such as instructions executed, cachemisses
952 suffered, or branches mis-predicted - without slowing down the
953 kernel or applications. These registers can also trigger interrupts
954 when a threshold number of events have passed - and can thus be
955 used to profile the code that runs on that CPU.
956
957 The Linux Performance Counter subsystem provides an abstraction of
958 these hardware capabilities, available via a system call. It
959 provides per task and per CPU counters, and it provides event
960 capabilities on top of those.
961
962 Say Y if unsure.
963
Peter Zijlstrae077df42009-03-19 20:26:17 +0100964config EVENT_PROFILE
965 bool "Tracepoint profile sources"
966 depends on PERF_COUNTERS && EVENT_TRACER
967 default y
968
Thomas Gleixner0793a612008-12-04 20:12:29 +0100969endmenu
970
Christoph Lameterf8891e52006-06-30 01:55:45 -0700971config VM_EVENT_COUNTERS
972 default y
973 bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
974 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -0800975 VM event counters are needed for event counts to be shown.
976 This option allows the disabling of the VM event counters
977 on EMBEDDED systems. /proc/vmstat will only show page counts
978 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -0700979
Thomas Petazzoni3d137312008-08-19 10:28:24 +0200980config PCI_QUIRKS
981 default y
Geert Uytterhoeven61cfc7e2008-10-22 08:53:25 +0200982 bool "Enable PCI quirk workarounds" if EMBEDDED
983 depends on PCI
Thomas Petazzoni3d137312008-08-19 10:28:24 +0200984 help
985 This enables workarounds for various PCI chipset
986 bugs/quirks. Disable this only if your target machine is
987 unaffected by PCI quirks.
988
Christoph Lameter41ecc552007-05-09 02:32:44 -0700989config SLUB_DEBUG
990 default y
991 bool "Enable SLUB debugging support" if EMBEDDED
Christoph Lameterf6acb632008-04-29 16:16:06 -0700992 depends on SLUB && SYSFS
Christoph Lameter41ecc552007-05-09 02:32:44 -0700993 help
994 SLUB has extensive debug support features. Disabling these can
995 result in significant savings in code size. This also disables
996 SLUB sysfs support. /sys/slab will not exist and there will be
997 no support for cache validation etc.
998
Randy Dunlapb943c462009-03-10 12:55:46 -0700999config COMPAT_BRK
1000 bool "Disable heap randomization"
1001 default y
1002 help
1003 Randomizing heap placement makes heap exploits harder, but it
1004 also breaks ancient binaries (including anything libc5 based).
1005 This option changes the bootup default to heap randomization
Matt LaPlante692105b2009-01-26 11:12:25 +01001006 disabled, and can be overridden at runtime by setting
Randy Dunlapb943c462009-03-10 12:55:46 -07001007 /proc/sys/kernel/randomize_va_space to 2.
1008
1009 On non-ancient distros (post-2000 ones) N is usually a safe choice.
1010
Christoph Lameter81819f02007-05-06 14:49:36 -07001011choice
1012 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -07001013 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001014 help
1015 This option allows to select a slab allocator.
1016
1017config SLAB
1018 bool "SLAB"
1019 help
1020 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -07001021 well in all environments. It organizes cache hot objects in
Simon Arlott02f56212008-11-05 22:18:19 +00001022 per cpu and per node queues.
Christoph Lameter81819f02007-05-06 14:49:36 -07001023
1024config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001025 bool "SLUB (Unqueued Allocator)"
1026 help
1027 SLUB is a slab allocator that minimizes cache line usage
1028 instead of managing queues of cached objects (SLAB approach).
1029 Per cpu caching is realized using slabs of objects instead
1030 of queues of objects. SLUB can use memory efficiently
Simon Arlott02f56212008-11-05 22:18:19 +00001031 and has enhanced diagnostics. SLUB is the default choice for
1032 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -07001033
1034config SLOB
Paul Mundt84a01c22007-07-15 23:38:24 -07001035 depends on EMBEDDED
Christoph Lameter81819f02007-05-06 14:49:36 -07001036 bool "SLOB (Simple Allocator)"
1037 help
Matt Mackall37291452008-02-04 22:29:38 -08001038 SLOB replaces the stock allocator with a drastically simpler
1039 allocator. SLOB is generally more space efficient but
1040 does not perform as well on large systems.
Christoph Lameter81819f02007-05-06 14:49:36 -07001041
1042endchoice
1043
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001044config PROFILING
1045 bool "Profiling support (EXPERIMENTAL)"
1046 help
1047 Say Y here to enable the extended profiling support mechanisms used
1048 by profilers such as OProfile.
1049
Ingo Molnar5f87f112008-07-23 14:15:22 +02001050#
1051# Place an empty function call at each tracepoint site. Can be
1052# dynamically changed for a probe function.
1053#
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001054config TRACEPOINTS
Ingo Molnar5f87f112008-07-23 14:15:22 +02001055 bool
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001056
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001057config MARKERS
1058 bool "Activate markers"
Frederic Weisbecker91f73f92009-02-20 17:34:06 +01001059 select TRACEPOINTS
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001060 help
1061 Place an empty function call at each marker site. Can be
1062 dynamically changed for a probe function.
1063
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -05001064source "arch/Kconfig"
1065
David Howells07fe7cb2009-04-03 16:42:35 +01001066config SLOW_WORK
1067 default n
David Howells1c2d0082009-04-06 15:47:25 +01001068 bool
David Howells07fe7cb2009-04-03 16:42:35 +01001069 help
1070 The slow work thread pool provides a number of dynamically allocated
1071 threads that can be used by the kernel to perform operations that
1072 take a relatively long time.
1073
1074 An example of this would be CacheFiles doing a path lookup followed
1075 by a series of mkdirs and a create call, all of which have to touch
1076 disk.
1077
David Howells1c2d0082009-04-06 15:47:25 +01001078 See Documentation/slow-work.txt.
1079
Linus Torvalds1da177e2005-04-16 15:20:36 -07001080endmenu # General setup
1081
Dmitry Baryshkovee7e5512008-06-29 14:18:46 +04001082config HAVE_GENERIC_DMA_COHERENT
1083 bool
1084 default n
1085
Linus Torvalds158a9622008-01-02 13:04:48 -08001086config SLABINFO
1087 bool
1088 depends on PROC_FS
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001089 depends on SLAB || SLUB_DEBUG
Linus Torvalds158a9622008-01-02 13:04:48 -08001090 default y
1091
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001092config RT_MUTEXES
1093 boolean
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001094
Linus Torvalds1da177e2005-04-16 15:20:36 -07001095config BASE_SMALL
1096 int
1097 default 0 if BASE_FULL
1098 default 1 if !BASE_FULL
1099
Jan Engelhardt66da5732007-07-15 23:39:29 -07001100menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001101 bool "Enable loadable module support"
1102 help
1103 Kernel modules are small pieces of compiled code which can
1104 be inserted in the running kernel, rather than being
1105 permanently built into the kernel. You use the "modprobe"
1106 tool to add (and sometimes remove) them. If you say Y here,
1107 many parts of the kernel can be built as modules (by
1108 answering M instead of Y where indicated): this is most
1109 useful for infrequently used options which are not required
1110 for booting. For more information, see the man pages for
1111 modprobe, lsmod, modinfo, insmod and rmmod.
1112
1113 If you say Y here, you will need to run "make
1114 modules_install" to put the modules under /lib/modules/
1115 where modprobe can find them (you may need to be root to do
1116 this).
1117
1118 If unsure, say Y.
1119
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001120if MODULES
1121
Linus Torvalds826e4502008-05-04 17:04:16 -07001122config MODULE_FORCE_LOAD
1123 bool "Forced module loading"
Linus Torvalds826e4502008-05-04 17:04:16 -07001124 default n
1125 help
Rusty Russell91e37a72008-05-09 16:25:28 +10001126 Allow loading of modules without version information (ie. modprobe
1127 --force). Forced module loading sets the 'F' (forced) taint flag and
1128 is usually a really bad idea.
Linus Torvalds826e4502008-05-04 17:04:16 -07001129
Linus Torvalds1da177e2005-04-16 15:20:36 -07001130config MODULE_UNLOAD
1131 bool "Module unloading"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001132 help
1133 Without this option you will not be able to unload any
1134 modules (note that some modules may not be unloadable
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001135 anyway), which makes your kernel smaller, faster
1136 and simpler. If unsure, say Y.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137
1138config MODULE_FORCE_UNLOAD
1139 bool "Forced module unloading"
1140 depends on MODULE_UNLOAD && EXPERIMENTAL
1141 help
1142 This option allows you to force a module to unload, even if the
1143 kernel believes it is unsafe: the kernel will remove the module
1144 without waiting for anyone to stop using it (using the -f option to
1145 rmmod). This is mainly for kernel developers and desperate users.
1146 If unsure, say N.
1147
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +01001149 bool "Module versioning support"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001150 help
1151 Usually, you have to use modules compiled with your kernel.
1152 Saying Y here makes it sometimes possible to use modules
1153 compiled for different kernels, by adding enough information
1154 to the modules to (hopefully) spot any changes which would
1155 make them incompatible with the kernel you are running. If
1156 unsure, say N.
1157
1158config MODULE_SRCVERSION_ALL
1159 bool "Source checksum for all modules"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001160 help
1161 Modules which contain a MODULE_VERSION get an extra "srcversion"
1162 field inserted into their modinfo section, which contains a
1163 sum of the source files which made it. This helps maintainers
1164 see exactly which source was used to build a module (since
1165 others sometimes change the module source without updating
1166 the version). With this option, such a "srcversion" field
1167 will be created for all modules. If unsure, say N.
1168
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001169endif # MODULES
1170
Rusty Russell98a79d62008-12-13 21:19:41 +10301171config INIT_ALL_POSSIBLE
1172 bool
1173 help
1174 Back when each arch used to define their own cpu_online_map and
1175 cpu_possible_map, some of them chose to initialize cpu_possible_map
1176 with all 1s, and others with all 0s. When they were centralised,
1177 it was better to provide this option than to break all the archs
Matt LaPlante692105b2009-01-26 11:12:25 +01001178 and have several arch maintainers pursuing me down dark alleys.
Rusty Russell98a79d62008-12-13 21:19:41 +10301179
Linus Torvalds1da177e2005-04-16 15:20:36 -07001180config STOP_MACHINE
1181 bool
1182 default y
1183 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
1184 help
1185 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001186
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001187source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -07001188
1189config PREEMPT_NOTIFIERS
1190 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +01001191