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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 Oberparleiterb99b87f2009-06-17 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47 drivers that have been replaced by something else, and/or are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 Dunlap34ad92c2005-10-30 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
Mike Travisc903ff82009-01-15 12:28:29 -0800319config TREE_RCU
320 bool "Tree-based hierarchical RCU"
321 help
322 This option selects the RCU implementation that is
323 designed for very large SMP system with hundreds or
Paul E. McKenneyc17ef452009-06-23 17:12:47 -0700324 thousands of CPUs. It also scales down nicely to
325 smaller systems.
Mike Travisc903ff82009-01-15 12:28:29 -0800326
327config PREEMPT_RCU
328 bool "Preemptible RCU"
329 depends on PREEMPT
330 help
331 This option reduces the latency of the kernel by making certain
332 RCU sections preemptible. Normally RCU code is non-preemptible, if
333 this option is selected then read-only RCU sections become
334 preemptible. This helps latency, but may expose bugs due to
335 now-naive assumptions about each RCU read-side critical section
336 remaining on a given CPU through its execution.
337
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700338config TREE_PREEMPT_RCU
339 bool "Preemptable tree-based hierarchical RCU"
340 depends on PREEMPT
341 help
342 This option selects the RCU implementation that is
343 designed for very large SMP systems with hundreds or
344 thousands of CPUs, but for which real-time response
345 is also required.
346
Mike Travisc903ff82009-01-15 12:28:29 -0800347endchoice
348
349config RCU_TRACE
350 bool "Enable tracing for RCU"
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700351 depends on TREE_RCU || PREEMPT_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800352 help
353 This option provides tracing in RCU which presents stats
354 in debugfs for debugging RCU implementation.
355
356 Say Y here if you want to enable RCU tracing
357 Say N if you are unsure.
358
359config RCU_FANOUT
360 int "Tree-based hierarchical RCU fanout value"
361 range 2 64 if 64BIT
362 range 2 32 if !64BIT
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700363 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800364 default 64 if 64BIT
365 default 32 if !64BIT
366 help
367 This option controls the fanout of hierarchical implementations
368 of RCU, allowing RCU to work efficiently on machines with
369 large numbers of CPUs. This value must be at least the cube
370 root of NR_CPUS, which allows NR_CPUS up to 32,768 for 32-bit
371 systems and up to 262,144 for 64-bit systems.
372
373 Select a specific number if testing RCU itself.
374 Take the default if unsure.
375
376config RCU_FANOUT_EXACT
377 bool "Disable tree-based hierarchical RCU auto-balancing"
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700378 depends on TREE_RCU || TREE_PREEMPT_RCU
Mike Travisc903ff82009-01-15 12:28:29 -0800379 default n
380 help
381 This option forces use of the exact RCU_FANOUT value specified,
382 regardless of imbalances in the hierarchy. This is useful for
383 testing RCU itself, and might one day be useful on systems with
384 strong NUMA behavior.
385
386 Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
387
388 Say N if unsure.
389
390config TREE_RCU_TRACE
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700391 def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
Mike Travisc903ff82009-01-15 12:28:29 -0800392 select DEBUG_FS
393 help
Paul E. McKenneyf41d9112009-08-22 13:56:52 -0700394 This option provides tracing for the TREE_RCU and
395 TREE_PREEMPT_RCU implementations, permitting Makefile to
396 trivially select kernel/rcutree_trace.c.
Mike Travisc903ff82009-01-15 12:28:29 -0800397
398config PREEMPT_RCU_TRACE
399 def_bool RCU_TRACE && PREEMPT_RCU
400 select DEBUG_FS
401 help
402 This option provides tracing for the PREEMPT_RCU implementation,
403 permitting Makefile to trivially select kernel/rcupreempt_trace.c.
404
405endmenu # "RCU Subsystem"
406
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700408 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 ---help---
410 This option enables the complete Linux kernel ".config" file
411 contents to be saved in the kernel. It provides documentation
412 of which kernel options are used in a running kernel or in an
413 on-disk kernel. This information can be extracted from the kernel
414 image file with the script scripts/extract-ikconfig and used as
415 input to rebuild the current kernel or to build another kernel.
416 It can also be extracted from a running kernel by reading
417 /proc/config.gz if enabled (below).
418
419config IKCONFIG_PROC
420 bool "Enable access to .config through /proc/config.gz"
421 depends on IKCONFIG && PROC_FS
422 ---help---
423 This option enables access to the kernel configuration file
424 through /proc/config.gz.
425
Alistair John Strachan794543a2007-05-08 00:31:15 -0700426config LOG_BUF_SHIFT
427 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
428 range 12 21
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700429 default 17
Alistair John Strachan794543a2007-05-08 00:31:15 -0700430 help
431 Select kernel log buffer size as a power of 2.
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700432 Examples:
433 17 => 128 KB
434 16 => 64 KB
435 15 => 32 KB
436 14 => 16 KB
Alistair John Strachan794543a2007-05-08 00:31:15 -0700437 13 => 8 KB
438 12 => 4 KB
439
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800440#
441# Architectures with an unreliable sched_clock() should select this:
442#
443config HAVE_UNSTABLE_SCHED_CLOCK
444 bool
445
446config GROUP_SCHED
447 bool "Group CPU scheduler"
448 depends on EXPERIMENTAL
449 default n
450 help
451 This feature lets CPU scheduler recognize task groups and control CPU
452 bandwidth allocation to such task groups.
453 In order to create a group from arbitrary set of processes, use
454 CONFIG_CGROUPS. (See Control Group support.)
455
456config FAIR_GROUP_SCHED
457 bool "Group scheduling for SCHED_OTHER"
458 depends on GROUP_SCHED
459 default GROUP_SCHED
460
461config RT_GROUP_SCHED
462 bool "Group scheduling for SCHED_RR/FIFO"
463 depends on EXPERIMENTAL
464 depends on GROUP_SCHED
465 default n
466 help
467 This feature lets you explicitly allocate real CPU bandwidth
468 to users or control groups (depending on the "Basis for grouping tasks"
469 setting below. If enabled, it will also make it impossible to
470 schedule realtime tasks for non-root users until you allocate
471 realtime bandwidth for them.
472 See Documentation/scheduler/sched-rt-group.txt for more information.
473
474choice
475 depends on GROUP_SCHED
476 prompt "Basis for grouping tasks"
477 default USER_SCHED
478
479config USER_SCHED
480 bool "user id"
481 help
482 This option will choose userid as the basis for grouping
483 tasks, thus providing equal CPU bandwidth to each user.
484
485config CGROUP_SCHED
486 bool "Control groups"
487 depends on CGROUPS
488 help
489 This option allows you to create arbitrary task groups
490 using the "cgroup" pseudo filesystem and control
491 the cpu bandwidth allocated to each such task group.
Li Zefan45ce80f2009-01-15 13:50:59 -0800492 Refer to Documentation/cgroups/cgroups.txt for more
493 information on "cgroup" pseudo filesystem.
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800494
495endchoice
496
Li Zefan23964d22009-01-15 13:50:58 -0800497menuconfig CGROUPS
498 boolean "Control Group support"
Paul Menageddbcc7e2007-10-18 23:39:30 -0700499 help
Li Zefan23964d22009-01-15 13:50:58 -0800500 This option adds support for grouping sets of processes together, for
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800501 use with process control subsystems such as Cpusets, CFS, memory
502 controls or device isolation.
503 See
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800504 - Documentation/scheduler/sched-design-CFS.txt (CFS)
Li Zefan45ce80f2009-01-15 13:50:59 -0800505 - Documentation/cgroups/ (features for grouping, isolation
506 and resource control)
Paul Menageddbcc7e2007-10-18 23:39:30 -0700507
508 Say N if unsure.
509
Li Zefan23964d22009-01-15 13:50:58 -0800510if CGROUPS
511
Paul Menage006cb992007-10-18 23:39:43 -0700512config CGROUP_DEBUG
513 bool "Example debug cgroup subsystem"
514 depends on CGROUPS
Paul Menage418d7d82008-04-29 01:00:05 -0700515 default n
Paul Menage006cb992007-10-18 23:39:43 -0700516 help
517 This option enables a simple cgroup subsystem that
518 exports useful debugging information about the cgroups
Li Zefan23964d22009-01-15 13:50:58 -0800519 framework.
Paul Menage006cb992007-10-18 23:39:43 -0700520
Li Zefan23964d22009-01-15 13:50:58 -0800521 Say N if unsure.
Paul Menage006cb992007-10-18 23:39:43 -0700522
Serge E. Hallyn858d72e2007-10-18 23:39:45 -0700523config CGROUP_NS
Li Zefan23964d22009-01-15 13:50:58 -0800524 bool "Namespace cgroup subsystem"
525 depends on CGROUPS
526 help
527 Provides a simple namespace cgroup subsystem to
528 provide hierarchical naming of sets of namespaces,
529 for instance virtual servers and checkpoint/restart
530 jobs.
Serge E. Hallyn858d72e2007-10-18 23:39:45 -0700531
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700532config CGROUP_FREEZER
Li Zefan23964d22009-01-15 13:50:58 -0800533 bool "Freezer cgroup subsystem"
534 depends on CGROUPS
535 help
536 Provides a way to freeze and unfreeze all tasks in a
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700537 cgroup.
538
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700539config CGROUP_DEVICE
540 bool "Device controller for cgroups"
541 depends on CGROUPS && EXPERIMENTAL
542 help
543 Provides a cgroup implementing whitelists for devices which
544 a process in the cgroup can mknod or open.
545
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546config CPUSETS
547 bool "Cpuset support"
Paul Menagedb7f47c2009-04-02 16:57:55 -0700548 depends on CGROUPS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700550 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551 allow dynamically partitioning a system into sets of CPUs and
552 Memory Nodes and assigning tasks to run only within those sets.
553 This is primarily useful on large SMP or NUMA systems.
554
555 Say N if unsure.
556
Li Zefan23964d22009-01-15 13:50:58 -0800557config PROC_PID_CPUSET
558 bool "Include legacy /proc/<pid>/cpuset file"
559 depends on CPUSETS
560 default y
561
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100562config CGROUP_CPUACCT
563 bool "Simple CPU accounting cgroup subsystem"
564 depends on CGROUPS
565 help
566 Provides a simple Resource Controller for monitoring the
Li Zefan23964d22009-01-15 13:50:58 -0800567 total CPU consumed by the tasks in a cgroup.
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100568
Pavel Emelianove552b662008-02-07 00:13:49 -0800569config RESOURCE_COUNTERS
570 bool "Resource counters"
571 help
572 This option enables controller independent resource accounting
Li Zefan23964d22009-01-15 13:50:58 -0800573 infrastructure that works with cgroups.
Pavel Emelianove552b662008-02-07 00:13:49 -0800574 depends on CGROUPS
575
Balbir Singh00f0b822008-03-04 14:28:39 -0800576config CGROUP_MEM_RES_CTLR
577 bool "Memory Resource Controller for Control Groups"
578 depends on CGROUPS && RESOURCE_COUNTERS
Balbir Singhcf475ad2008-04-29 01:00:16 -0700579 select MM_OWNER
Balbir Singh00f0b822008-03-04 14:28:39 -0800580 help
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700581 Provides a memory resource controller that manages both anonymous
Thadeu Lima de Souza Cascardo21acb9c2009-02-04 10:12:08 +0100582 memory and page cache. (See Documentation/cgroups/memory.txt)
Balbir Singh00f0b822008-03-04 14:28:39 -0800583
584 Note that setting this option increases fixed memory overhead
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700585 associated with each page of memory in the system. By this,
586 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
587 usage tracking struct at boot. Total amount of this is printed out
588 at boot.
Balbir Singh00f0b822008-03-04 14:28:39 -0800589
590 Only enable when you're ok with these trade offs and really
KAMEZAWA Hiroyuki84ad6d72008-10-29 14:01:06 -0700591 sure you need the memory resource controller. Even when you enable
592 this, you can set "cgroup_disable=memory" at your boot option to
593 disable memory resource controller and you can avoid overheads.
Li Zefanc9d54092009-01-07 18:07:35 -0800594 (and lose benefits of memory resource controller)
Balbir Singh00f0b822008-03-04 14:28:39 -0800595
Balbir Singhcf475ad2008-04-29 01:00:16 -0700596 This config option also selects MM_OWNER config option, which
597 could in turn add some fork/exit overhead.
598
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800599config CGROUP_MEM_RES_CTLR_SWAP
600 bool "Memory Resource Controller Swap Extension(EXPERIMENTAL)"
601 depends on CGROUP_MEM_RES_CTLR && SWAP && EXPERIMENTAL
602 help
603 Add swap management feature to memory resource controller. When you
604 enable this, you can limit mem+swap usage per cgroup. In other words,
605 when you disable this, memory resource controller has no cares to
606 usage of swap...a process can exhaust all of the swap. This extension
607 is useful when you want to avoid exhaustion swap but this itself
608 adds more overheads and consumes memory for remembering information.
609 Especially if you use 32bit system or small memory system, please
610 be careful about enabling this. When memory resource controller
611 is disabled by boot option, this will be automatically disabled and
612 there will be no overhead from this. Even when you set this config=y,
613 if boot option "noswapaccount" is set, swap will not be accounted.
KAMEZAWA Hiroyuki627991a2009-04-02 16:57:47 -0700614 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
615 size is 4096bytes, 512k per 1Gbytes of swap.
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800616
Li Zefan23964d22009-01-15 13:50:58 -0800617endif # CGROUPS
KAMEZAWA Hiroyukic0777192009-01-07 18:07:57 -0800618
Li Zefan23964d22009-01-15 13:50:58 -0800619config MM_OWNER
620 bool
KAMEZAWA Hiroyuki5cdc38f2009-01-07 18:07:30 -0800621
Kay Sievers88a22c92006-09-14 11:23:28 +0200622config SYSFS_DEPRECATED
Ingo Molnard47846c2008-03-04 14:54:47 +0100623 bool
624
625config SYSFS_DEPRECATED_V2
Kay Sieversf6ee6492009-04-16 19:56:37 +0200626 bool "remove sysfs features which may confuse old userspace tools"
Randy Dunlap9148fe82007-12-31 10:05:34 -0800627 depends on SYSFS
Kay Sieversf6ee6492009-04-16 19:56:37 +0200628 default n
Ingo Molnard47846c2008-03-04 14:54:47 +0100629 select SYSFS_DEPRECATED
Kay Sievers88a22c92006-09-14 11:23:28 +0200630 help
Kay Sieversfce3e802008-11-01 14:03:00 +0100631 This option switches the layout of sysfs to the deprecated
Kay Sieversf6ee6492009-04-16 19:56:37 +0200632 version. Do not use it on recent distributions.
Kay Sievers88a22c92006-09-14 11:23:28 +0200633
Kay Sieversfce3e802008-11-01 14:03:00 +0100634 The current sysfs layout features a unified device tree at
635 /sys/devices/, which is able to express a hierarchy between
636 class devices. If the deprecated option is set to Y, the
637 unified device tree is split into a bus device tree at
638 /sys/devices/ and several individual class device trees at
639 /sys/class/. The class and bus devices will be connected by
640 "<subsystem>:<name>" and the "device" links. The "block"
641 class devices, will not show up in /sys/class/block/. Some
642 subsystems will suppress the creation of some devices which
643 depend on the unified device tree.
Kay Sievers88a22c92006-09-14 11:23:28 +0200644
Kay Sieversfce3e802008-11-01 14:03:00 +0100645 This option is not a pure compatibility option that can
646 be safely enabled on newer distributions. It will change the
647 layout of sysfs to the non-extensible deprecated version,
648 and disable some features, which can not be exported without
649 confusing older userspace tools. Since 2007/2008 all major
650 distributions do not enable this option, and ship no tools which
651 depend on the deprecated layout or this option.
652
653 If you are using a new kernel on an older distribution, or use
654 older userspace tools, you might need to say Y here. Do not say Y,
655 if the original kernel, that came with your distribution, has
656 this option set to N.
Kay Sievers88a22c92006-09-14 11:23:28 +0200657
Jens Axboeb86ff9812006-03-23 19:56:55 +0100658config RELAY
659 bool "Kernel->user space relay support (formerly relayfs)"
660 help
661 This option enables support for relay interface support in
662 certain file systems (such as debugfs).
663 It is designed to provide an efficient mechanism for tools and
664 facilities to relay large amounts of data from kernel space to
665 user space.
666
667 If unsure, say N.
668
Pavel Emelyanovc5289a62008-02-08 04:18:19 -0800669config NAMESPACES
670 bool "Namespaces support" if EMBEDDED
671 default !EMBEDDED
672 help
673 Provides the way to make tasks work with different objects using
674 the same id. For example same IPC id may refer to different objects
675 or same user id or pid may refer to different tasks when used in
676 different namespaces.
677
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -0800678config UTS_NS
679 bool "UTS namespace"
680 depends on NAMESPACES
681 help
682 In this namespace tasks see different info provided with the
683 uname() system call
684
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800685config IPC_NS
686 bool "IPC namespace"
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700687 depends on NAMESPACES && (SYSVIPC || POSIX_MQUEUE)
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800688 help
689 In this namespace tasks work with IPC ids which correspond to
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700690 different IPC objects in different namespaces.
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800691
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -0800692config USER_NS
693 bool "User namespace (EXPERIMENTAL)"
694 depends on NAMESPACES && EXPERIMENTAL
695 help
696 This allows containers, i.e. vservers, to use user namespaces
697 to provide different user info for different servers.
698 If unsure, say N.
699
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800700config PID_NS
701 bool "PID Namespaces (EXPERIMENTAL)"
702 default n
703 depends on NAMESPACES && EXPERIMENTAL
704 help
Heikki Orsila12d2b8f2008-07-06 15:48:02 +0300705 Support process id namespaces. This allows having multiple
Matt LaPlante692105b2009-01-26 11:12:25 +0100706 processes with the same pid as long as they are in different
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800707 pid namespaces. This is a building block of containers.
708
709 Unless you want to work with an experimental feature
710 say N here.
711
Matt Helsleyd6eb6332009-01-26 12:25:55 -0800712config NET_NS
713 bool "Network namespace"
714 default n
715 depends on NAMESPACES && EXPERIMENTAL && NET
716 help
717 Allow user space to create what appear to be multiple instances
718 of the network stack.
719
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -0800720config BLK_DEV_INITRD
721 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
722 depends on BROKEN || !FRV
723 help
724 The initial RAM filesystem is a ramfs which is loaded by the
725 boot loader (loadlin or lilo) and that is mounted as root
726 before the normal boot procedure. It is typically used to
727 load modules needed to mount the "real" root file system,
728 etc. See <file:Documentation/initrd.txt> for details.
729
730 If RAM disk support (BLK_DEV_RAM) is also included, this
731 also enables initial RAM disk (initrd) support and adds
732 15 Kbytes (more on some other architectures) to the kernel size.
733
734 If unsure say Y.
735
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800736if BLK_DEV_INITRD
737
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200738source "usr/Kconfig"
739
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800740endif
741
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800742config CC_OPTIMIZE_FOR_SIZE
Ingo Molnar96fffeb2008-04-28 01:39:43 +0200743 bool "Optimize for size"
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800744 default y
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800745 help
746 Enabling this option will pass "-Os" instead of "-O2" to gcc
747 resulting in a smaller kernel.
748
jkacur775a7222008-07-16 00:31:16 +0200749 If unsure, say Y.
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800750
Randy Dunlap08470622006-09-30 23:28:13 -0700751config SYSCTL
752 bool
753
Randy Dunlapb943c462009-03-10 12:55:46 -0700754config ANON_INODES
755 bool
756
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757menuconfig EMBEDDED
758 bool "Configure standard kernel features (for small systems)"
759 help
760 This option allows certain base kernel options and settings
761 to be disabled or tweaked. This is for specialized
762 environments which can tolerate a "non-standard" kernel.
763 Only use this if you really know what you are doing.
764
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700765config UID16
766 bool "Enable 16-bit UID system calls" if EMBEDDED
David S. Miller09337f52008-04-26 03:17:12 -0700767 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 -0700768 default y
769 help
770 This enables the legacy 16-bit UID syscall wrappers.
771
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700772config SYSCTL_SYSCALL
Randy Dunlap08470622006-09-30 23:28:13 -0700773 bool "Sysctl syscall support" if EMBEDDED
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800774 default y
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700775 select SYSCTL
776 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800777 sys_sysctl uses binary paths that have been found challenging
778 to properly maintain and use. The interface in /proc/sys
779 using paths with ascii names is now the primary path to this
780 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700781
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800782 Almost nothing using the binary sysctl interface so if you are
783 trying to save some space it is probably safe to disable this,
784 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700785
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800786 If unsure say Y here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700787
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788config KALLSYMS
Jesper Juhl979c6a12006-12-12 19:25:11 +0100789 bool "Load all symbols for debugging/ksymoops" if EMBEDDED
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790 default y
791 help
792 Say Y here to let the kernel print out symbolic crash information and
793 symbolic stack backtraces. This increases the size of the kernel
794 somewhat, as all symbols have to be loaded into the kernel image.
795
796config KALLSYMS_ALL
797 bool "Include all symbols in kallsyms"
798 depends on DEBUG_KERNEL && KALLSYMS
799 help
800 Normally kallsyms only contains the symbols of functions, for nicer
801 OOPS messages. Some debuggers can use kallsyms for other
Jesper Juhlf9f97bc2005-07-20 05:43:05 +0200802 symbols too: say Y here to include all symbols, if you need them
803 and you don't care about adding 300k to the size of your kernel.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804
805 Say N.
806
807config KALLSYMS_EXTRA_PASS
808 bool "Do an extra kallsyms pass"
809 depends on KALLSYMS
810 help
811 If kallsyms is not working correctly, the build will fail with
812 inconsistent kallsyms data. If that occurs, log a bug report and
813 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
814 Always say N here unless you find a bug in kallsyms, which must be
815 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
816 you wait for kallsyms to be fixed.
817
Matt Mackalld59745c2005-05-01 08:59:02 -0700818
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
Mike Frysinger018df722009-06-12 13:17:43 -0400938 help
939 See tools/perf/design.txt for details.
Thomas Gleixner0793a612008-12-04 20:12:29 +0100940
941menu "Performance Counters"
942
943config PERF_COUNTERS
944 bool "Kernel Performance Counters"
Ingo Molnarf2654262009-06-29 10:40:20 +0200945 default y if PROFILING
Thomas Gleixner0793a612008-12-04 20:12:29 +0100946 depends on HAVE_PERF_COUNTERS
Ingo Molnar4c59e462008-12-08 19:38:33 +0100947 select ANON_INODES
Thomas Gleixner0793a612008-12-04 20:12:29 +0100948 help
949 Enable kernel support for performance counter hardware.
950
951 Performance counters are special hardware registers available
952 on most modern CPUs. These registers count the number of certain
953 types of hw events: such as instructions executed, cachemisses
954 suffered, or branches mis-predicted - without slowing down the
955 kernel or applications. These registers can also trigger interrupts
956 when a threshold number of events have passed - and can thus be
957 used to profile the code that runs on that CPU.
958
959 The Linux Performance Counter subsystem provides an abstraction of
960 these hardware capabilities, available via a system call. It
961 provides per task and per CPU counters, and it provides event
962 capabilities on top of those.
963
964 Say Y if unsure.
965
Peter Zijlstrae077df42009-03-19 20:26:17 +0100966config EVENT_PROFILE
Peter Zijlstra470a1392009-07-29 10:50:09 +0200967 bool "Tracepoint profiling sources"
Chris Wilsond4d7d0b2009-07-06 09:31:33 +0100968 depends on PERF_COUNTERS && EVENT_TRACING
Peter Zijlstrae077df42009-03-19 20:26:17 +0100969 default y
Peter Zijlstra470a1392009-07-29 10:50:09 +0200970 help
971 Allow the use of tracepoints as software performance counters.
972
973 When this is enabled, you can create perf counters based on
974 tracepoints using PERF_TYPE_TRACEPOINT and the tracepoint ID
975 found in debugfs://tracing/events/*/*/id. (The -e/--events
976 option to the perf tool can parse and interpret symbolic
977 tracepoints, in the subsystem:tracepoint_name format.)
Peter Zijlstrae077df42009-03-19 20:26:17 +0100978
Thomas Gleixner0793a612008-12-04 20:12:29 +0100979endmenu
980
Christoph Lameterf8891e52006-06-30 01:55:45 -0700981config VM_EVENT_COUNTERS
982 default y
983 bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
984 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -0800985 VM event counters are needed for event counts to be shown.
986 This option allows the disabling of the VM event counters
987 on EMBEDDED systems. /proc/vmstat will only show page counts
988 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -0700989
Thomas Petazzoni3d137312008-08-19 10:28:24 +0200990config PCI_QUIRKS
991 default y
Geert Uytterhoeven61cfc7e2008-10-22 08:53:25 +0200992 bool "Enable PCI quirk workarounds" if EMBEDDED
993 depends on PCI
Thomas Petazzoni3d137312008-08-19 10:28:24 +0200994 help
995 This enables workarounds for various PCI chipset
996 bugs/quirks. Disable this only if your target machine is
997 unaffected by PCI quirks.
998
Christoph Lameter41ecc552007-05-09 02:32:44 -0700999config SLUB_DEBUG
1000 default y
1001 bool "Enable SLUB debugging support" if EMBEDDED
Christoph Lameterf6acb632008-04-29 16:16:06 -07001002 depends on SLUB && SYSFS
Christoph Lameter41ecc552007-05-09 02:32:44 -07001003 help
1004 SLUB has extensive debug support features. Disabling these can
1005 result in significant savings in code size. This also disables
1006 SLUB sysfs support. /sys/slab will not exist and there will be
1007 no support for cache validation etc.
1008
Randy Dunlapa9eb5222009-06-05 15:02:47 -07001009config STRIP_ASM_SYMS
1010 bool "Strip assembler-generated symbols during link"
1011 default n
1012 help
1013 Strip internal assembler-generated symbols during a link (symbols
1014 that look like '.Lxxx') so they don't pollute the output of
1015 get_wchan() and suchlike.
1016
Randy Dunlapb943c462009-03-10 12:55:46 -07001017config COMPAT_BRK
1018 bool "Disable heap randomization"
1019 default y
1020 help
1021 Randomizing heap placement makes heap exploits harder, but it
1022 also breaks ancient binaries (including anything libc5 based).
1023 This option changes the bootup default to heap randomization
Matt LaPlante692105b2009-01-26 11:12:25 +01001024 disabled, and can be overridden at runtime by setting
Randy Dunlapb943c462009-03-10 12:55:46 -07001025 /proc/sys/kernel/randomize_va_space to 2.
1026
1027 On non-ancient distros (post-2000 ones) N is usually a safe choice.
1028
Christoph Lameter81819f02007-05-06 14:49:36 -07001029choice
1030 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -07001031 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001032 help
1033 This option allows to select a slab allocator.
1034
1035config SLAB
1036 bool "SLAB"
1037 help
1038 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -07001039 well in all environments. It organizes cache hot objects in
Simon Arlott02f56212008-11-05 22:18:19 +00001040 per cpu and per node queues.
Christoph Lameter81819f02007-05-06 14:49:36 -07001041
1042config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -07001043 bool "SLUB (Unqueued Allocator)"
1044 help
1045 SLUB is a slab allocator that minimizes cache line usage
1046 instead of managing queues of cached objects (SLAB approach).
1047 Per cpu caching is realized using slabs of objects instead
1048 of queues of objects. SLUB can use memory efficiently
Simon Arlott02f56212008-11-05 22:18:19 +00001049 and has enhanced diagnostics. SLUB is the default choice for
1050 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -07001051
1052config SLOB
Paul Mundt84a01c22007-07-15 23:38:24 -07001053 depends on EMBEDDED
Christoph Lameter81819f02007-05-06 14:49:36 -07001054 bool "SLOB (Simple Allocator)"
1055 help
Matt Mackall37291452008-02-04 22:29:38 -08001056 SLOB replaces the stock allocator with a drastically simpler
1057 allocator. SLOB is generally more space efficient but
1058 does not perform as well on large systems.
Christoph Lameter81819f02007-05-06 14:49:36 -07001059
1060endchoice
1061
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001062config PROFILING
1063 bool "Profiling support (EXPERIMENTAL)"
1064 help
1065 Say Y here to enable the extended profiling support mechanisms used
1066 by profilers such as OProfile.
1067
Ingo Molnar5f87f112008-07-23 14:15:22 +02001068#
1069# Place an empty function call at each tracepoint site. Can be
1070# dynamically changed for a probe function.
1071#
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001072config TRACEPOINTS
Ingo Molnar5f87f112008-07-23 14:15:22 +02001073 bool
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04001074
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001075config MARKERS
1076 bool "Activate markers"
Frederic Weisbecker91f73f92009-02-20 17:34:06 +01001077 select TRACEPOINTS
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05001078 help
1079 Place an empty function call at each marker site. Can be
1080 dynamically changed for a probe function.
1081
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -05001082source "arch/Kconfig"
1083
David Howells07fe7cb2009-04-03 16:42:35 +01001084config SLOW_WORK
1085 default n
David Howells1c2d0082009-04-06 15:47:25 +01001086 bool
David Howells07fe7cb2009-04-03 16:42:35 +01001087 help
1088 The slow work thread pool provides a number of dynamically allocated
1089 threads that can be used by the kernel to perform operations that
1090 take a relatively long time.
1091
1092 An example of this would be CacheFiles doing a path lookup followed
1093 by a series of mkdirs and a create call, all of which have to touch
1094 disk.
1095
David Howells1c2d0082009-04-06 15:47:25 +01001096 See Documentation/slow-work.txt.
1097
Linus Torvalds1da177e2005-04-16 15:20:36 -07001098endmenu # General setup
1099
Dmitry Baryshkovee7e5512008-06-29 14:18:46 +04001100config HAVE_GENERIC_DMA_COHERENT
1101 bool
1102 default n
1103
Linus Torvalds158a9622008-01-02 13:04:48 -08001104config SLABINFO
1105 bool
1106 depends on PROC_FS
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001107 depends on SLAB || SLUB_DEBUG
Linus Torvalds158a9622008-01-02 13:04:48 -08001108 default y
1109
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001110config RT_MUTEXES
1111 boolean
Chuck Ebbertae81f9e2006-09-16 12:15:53 -07001112
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113config BASE_SMALL
1114 int
1115 default 0 if BASE_FULL
1116 default 1 if !BASE_FULL
1117
Jan Engelhardt66da5732007-07-15 23:39:29 -07001118menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001119 bool "Enable loadable module support"
1120 help
1121 Kernel modules are small pieces of compiled code which can
1122 be inserted in the running kernel, rather than being
1123 permanently built into the kernel. You use the "modprobe"
1124 tool to add (and sometimes remove) them. If you say Y here,
1125 many parts of the kernel can be built as modules (by
1126 answering M instead of Y where indicated): this is most
1127 useful for infrequently used options which are not required
1128 for booting. For more information, see the man pages for
1129 modprobe, lsmod, modinfo, insmod and rmmod.
1130
1131 If you say Y here, you will need to run "make
1132 modules_install" to put the modules under /lib/modules/
1133 where modprobe can find them (you may need to be root to do
1134 this).
1135
1136 If unsure, say Y.
1137
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001138if MODULES
1139
Linus Torvalds826e4502008-05-04 17:04:16 -07001140config MODULE_FORCE_LOAD
1141 bool "Forced module loading"
Linus Torvalds826e4502008-05-04 17:04:16 -07001142 default n
1143 help
Rusty Russell91e37a72008-05-09 16:25:28 +10001144 Allow loading of modules without version information (ie. modprobe
1145 --force). Forced module loading sets the 'F' (forced) taint flag and
1146 is usually a really bad idea.
Linus Torvalds826e4502008-05-04 17:04:16 -07001147
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148config MODULE_UNLOAD
1149 bool "Module unloading"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001150 help
1151 Without this option you will not be able to unload any
1152 modules (note that some modules may not be unloadable
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001153 anyway), which makes your kernel smaller, faster
1154 and simpler. If unsure, say Y.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001155
1156config MODULE_FORCE_UNLOAD
1157 bool "Forced module unloading"
1158 depends on MODULE_UNLOAD && EXPERIMENTAL
1159 help
1160 This option allows you to force a module to unload, even if the
1161 kernel believes it is unsafe: the kernel will remove the module
1162 without waiting for anyone to stop using it (using the -f option to
1163 rmmod). This is mainly for kernel developers and desperate users.
1164 If unsure, say N.
1165
Linus Torvalds1da177e2005-04-16 15:20:36 -07001166config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +01001167 bool "Module versioning support"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001168 help
1169 Usually, you have to use modules compiled with your kernel.
1170 Saying Y here makes it sometimes possible to use modules
1171 compiled for different kernels, by adding enough information
1172 to the modules to (hopefully) spot any changes which would
1173 make them incompatible with the kernel you are running. If
1174 unsure, say N.
1175
1176config MODULE_SRCVERSION_ALL
1177 bool "Source checksum for all modules"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001178 help
1179 Modules which contain a MODULE_VERSION get an extra "srcversion"
1180 field inserted into their modinfo section, which contains a
1181 sum of the source files which made it. This helps maintainers
1182 see exactly which source was used to build a module (since
1183 others sometimes change the module source without updating
1184 the version). With this option, such a "srcversion" field
1185 will be created for all modules. If unsure, say N.
1186
Robert P. J. Day0b0de142008-08-04 13:31:32 -04001187endif # MODULES
1188
Rusty Russell98a79d62008-12-13 21:19:41 +10301189config INIT_ALL_POSSIBLE
1190 bool
1191 help
1192 Back when each arch used to define their own cpu_online_map and
1193 cpu_possible_map, some of them chose to initialize cpu_possible_map
1194 with all 1s, and others with all 0s. When they were centralised,
1195 it was better to provide this option than to break all the archs
Matt LaPlante692105b2009-01-26 11:12:25 +01001196 and have several arch maintainers pursuing me down dark alleys.
Rusty Russell98a79d62008-12-13 21:19:41 +10301197
Linus Torvalds1da177e2005-04-16 15:20:36 -07001198config STOP_MACHINE
1199 bool
1200 default y
1201 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
1202 help
1203 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001204
Jens Axboe3a65dfe2005-11-04 08:43:35 +01001205source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -07001206
1207config PREEMPT_NOTIFIERS
1208 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +01001209