xref: /openbmc/linux/init/Kconfig (revision e5e1d3cb)
180daa560SRoman Zippelconfig ARCH
280daa560SRoman Zippel	string
380daa560SRoman Zippel	option env="ARCH"
480daa560SRoman Zippel
580daa560SRoman Zippelconfig KERNELVERSION
680daa560SRoman Zippel	string
780daa560SRoman Zippel	option env="KERNELVERSION"
880daa560SRoman Zippel
9face4374SRoman Zippelconfig DEFCONFIG_LIST
10face4374SRoman Zippel	string
11b2670eacSPaolo 'Blaisorblade' Giarrusso	depends on !UML
12face4374SRoman Zippel	option defconfig_list
13face4374SRoman Zippel	default "/lib/modules/$UNAME_RELEASE/.config"
14face4374SRoman Zippel	default "/etc/kernel-config"
15face4374SRoman Zippel	default "/boot/config-$UNAME_RELEASE"
16face4374SRoman Zippel	default "arch/$ARCH/defconfig"
17face4374SRoman Zippel
18ff0cfc66SAl Boldimenu "General setup"
191da177e4SLinus Torvalds
201da177e4SLinus Torvaldsconfig EXPERIMENTAL
211da177e4SLinus Torvalds	bool "Prompt for development and/or incomplete code/drivers"
221da177e4SLinus Torvalds	---help---
231da177e4SLinus Torvalds	  Some of the various things that Linux supports (such as network
241da177e4SLinus Torvalds	  drivers, file systems, network protocols, etc.) can be in a state
251da177e4SLinus Torvalds	  of development where the functionality, stability, or the level of
261da177e4SLinus Torvalds	  testing is not yet high enough for general use. This is usually
271da177e4SLinus Torvalds	  known as the "alpha-test" phase among developers. If a feature is
281da177e4SLinus Torvalds	  currently in alpha-test, then the developers usually discourage
291da177e4SLinus Torvalds	  uninformed widespread use of this feature by the general public to
301da177e4SLinus Torvalds	  avoid "Why doesn't this work?" type mail messages. However, active
311da177e4SLinus Torvalds	  testing and use of these systems is welcomed. Just be aware that it
321da177e4SLinus Torvalds	  may not meet the normal level of reliability or it may fail to work
331da177e4SLinus Torvalds	  in some special cases. Detailed bug reports from people familiar
341da177e4SLinus Torvalds	  with the kernel internals are usually welcomed by the developers
351da177e4SLinus Torvalds	  (before submitting bug reports, please read the documents
361da177e4SLinus Torvalds	  <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
371da177e4SLinus Torvalds	  <file:Documentation/BUG-HUNTING>, and
381da177e4SLinus Torvalds	  <file:Documentation/oops-tracing.txt> in the kernel source).
391da177e4SLinus Torvalds
401da177e4SLinus Torvalds	  This option will also make obsoleted drivers available. These are
411da177e4SLinus Torvalds	  drivers that have been replaced by something else, and/or are
421da177e4SLinus Torvalds	  scheduled to be removed in a future kernel release.
431da177e4SLinus Torvalds
441da177e4SLinus Torvalds	  Unless you intend to help test and develop a feature or driver that
451da177e4SLinus Torvalds	  falls into this category, or you have a situation that requires
461da177e4SLinus Torvalds	  using these features, you should probably say N here, which will
471da177e4SLinus Torvalds	  cause the configurator to present you with fewer choices. If
481da177e4SLinus Torvalds	  you say Y here, you will be offered the choice of using features or
491da177e4SLinus Torvalds	  drivers that are currently considered to be in the alpha-test phase.
501da177e4SLinus Torvalds
511da177e4SLinus Torvaldsconfig BROKEN
521da177e4SLinus Torvalds	bool
531da177e4SLinus Torvalds
541da177e4SLinus Torvaldsconfig BROKEN_ON_SMP
551da177e4SLinus Torvalds	bool
561da177e4SLinus Torvalds	depends on BROKEN || !SMP
571da177e4SLinus Torvalds	default y
581da177e4SLinus Torvalds
591da177e4SLinus Torvaldsconfig LOCK_KERNEL
601da177e4SLinus Torvalds	bool
611da177e4SLinus Torvalds	depends on SMP || PREEMPT
621da177e4SLinus Torvalds	default y
631da177e4SLinus Torvalds
641da177e4SLinus Torvaldsconfig INIT_ENV_ARG_LIMIT
651da177e4SLinus Torvalds	int
66dd673bcaSAdrian Bunk	default 32 if !UML
67dd673bcaSAdrian Bunk	default 128 if UML
681da177e4SLinus Torvalds	help
6934ad92c2SRandy Dunlap	  Maximum of each of the number of arguments and environment
7034ad92c2SRandy Dunlap	  variables passed to init from the kernel command line.
711da177e4SLinus Torvalds
721da177e4SLinus Torvalds
731da177e4SLinus Torvaldsconfig LOCALVERSION
741da177e4SLinus Torvalds	string "Local version - append to kernel release"
751da177e4SLinus Torvalds	help
761da177e4SLinus Torvalds	  Append an extra string to the end of your kernel version.
771da177e4SLinus Torvalds	  This will show up when you type uname, for example.
781da177e4SLinus Torvalds	  The string you set here will be appended after the contents of
791da177e4SLinus Torvalds	  any files with a filename matching localversion* in your
801da177e4SLinus Torvalds	  object and source tree, in that order.  Your total string can
811da177e4SLinus Torvalds	  be a maximum of 64 characters.
821da177e4SLinus Torvalds
83aaebf433SRyan Andersonconfig LOCALVERSION_AUTO
84aaebf433SRyan Anderson	bool "Automatically append version information to the version string"
85aaebf433SRyan Anderson	default y
86aaebf433SRyan Anderson	help
87aaebf433SRyan Anderson	  This will try to automatically determine if the current tree is a
886e5a5420SRobert P. J. Day	  release tree by looking for git tags that belong to the current
896e5a5420SRobert P. J. Day	  top of tree revision.
90aaebf433SRyan Anderson
91aaebf433SRyan Anderson	  A string of the format -gxxxxxxxx will be added to the localversion
926e5a5420SRobert P. J. Day	  if a git-based tree is found.  The string generated by this will be
93aaebf433SRyan Anderson	  appended after any matching localversion* files, and after the value
946e5a5420SRobert P. J. Day	  set in CONFIG_LOCALVERSION.
95aaebf433SRyan Anderson
966e5a5420SRobert P. J. Day	  (The actual string used here is the first eight characters produced
976e5a5420SRobert P. J. Day	  by running the command:
986e5a5420SRobert P. J. Day
996e5a5420SRobert P. J. Day	    $ git rev-parse --verify HEAD
1006e5a5420SRobert P. J. Day
1016e5a5420SRobert P. J. Day	  which is done within the script "scripts/setlocalversion".)
102aaebf433SRyan Anderson
1031da177e4SLinus Torvaldsconfig SWAP
1041da177e4SLinus Torvalds	bool "Support for paging of anonymous memory (swap)"
1059361401eSDavid Howells	depends on MMU && BLOCK
1061da177e4SLinus Torvalds	default y
1071da177e4SLinus Torvalds	help
1081da177e4SLinus Torvalds	  This option allows you to choose whether you want to have support
1091da177e4SLinus Torvalds	  for so called swap devices or swap files in your kernel that are
1101da177e4SLinus Torvalds	  used to provide more virtual memory than the actual RAM present
1111da177e4SLinus Torvalds	  in your computer.  If unsure say Y.
1121da177e4SLinus Torvalds
1131da177e4SLinus Torvaldsconfig SYSVIPC
1141da177e4SLinus Torvalds	bool "System V IPC"
1151da177e4SLinus Torvalds	---help---
1161da177e4SLinus Torvalds	  Inter Process Communication is a suite of library functions and
1171da177e4SLinus Torvalds	  system calls which let processes (running programs) synchronize and
1181da177e4SLinus Torvalds	  exchange information. It is generally considered to be a good thing,
1191da177e4SLinus Torvalds	  and some programs won't run unless you say Y here. In particular, if
1201da177e4SLinus Torvalds	  you want to run the DOS emulator dosemu under Linux (read the
1211da177e4SLinus Torvalds	  DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
1221da177e4SLinus Torvalds	  you'll need to say Y here.
1231da177e4SLinus Torvalds
1241da177e4SLinus Torvalds	  You can find documentation about IPC with "info ipc" and also in
1251da177e4SLinus Torvalds	  section 6.4 of the Linux Programmer's Guide, available from
1261da177e4SLinus Torvalds	  <http://www.tldp.org/guides.html>.
1271da177e4SLinus Torvalds
128a5494dcdSEric W. Biedermanconfig SYSVIPC_SYSCTL
129a5494dcdSEric W. Biederman	bool
130a5494dcdSEric W. Biederman	depends on SYSVIPC
131a5494dcdSEric W. Biederman	depends on SYSCTL
132a5494dcdSEric W. Biederman	default y
133a5494dcdSEric W. Biederman
1341da177e4SLinus Torvaldsconfig POSIX_MQUEUE
1351da177e4SLinus Torvalds	bool "POSIX Message Queues"
1361da177e4SLinus Torvalds	depends on NET && EXPERIMENTAL
1371da177e4SLinus Torvalds	---help---
1381da177e4SLinus Torvalds	  POSIX variant of message queues is a part of IPC. In POSIX message
1391da177e4SLinus Torvalds	  queues every message has a priority which decides about succession
1401da177e4SLinus Torvalds	  of receiving it by a process. If you want to compile and run
1411da177e4SLinus Torvalds	  programs written e.g. for Solaris with use of its POSIX message
142b0e37650SRobert P. J. Day	  queues (functions mq_*) say Y here.
1431da177e4SLinus Torvalds
1441da177e4SLinus Torvalds	  POSIX message queues are visible as a filesystem called 'mqueue'
1451da177e4SLinus Torvalds	  and can be mounted somewhere if you want to do filesystem
1461da177e4SLinus Torvalds	  operations on message queues.
1471da177e4SLinus Torvalds
1481da177e4SLinus Torvalds	  If unsure, say Y.
1491da177e4SLinus Torvalds
1501da177e4SLinus Torvaldsconfig BSD_PROCESS_ACCT
1511da177e4SLinus Torvalds	bool "BSD Process Accounting"
1521da177e4SLinus Torvalds	help
1531da177e4SLinus Torvalds	  If you say Y here, a user level program will be able to instruct the
1541da177e4SLinus Torvalds	  kernel (via a special system call) to write process accounting
1551da177e4SLinus Torvalds	  information to a file: whenever a process exits, information about
1561da177e4SLinus Torvalds	  that process will be appended to the file by the kernel.  The
1571da177e4SLinus Torvalds	  information includes things such as creation time, owning user,
1581da177e4SLinus Torvalds	  command name, memory usage, controlling terminal etc. (the complete
1591da177e4SLinus Torvalds	  list is in the struct acct in <file:include/linux/acct.h>).  It is
1601da177e4SLinus Torvalds	  up to the user level program to do useful things with this
1611da177e4SLinus Torvalds	  information.  This is generally a good idea, so say Y.
1621da177e4SLinus Torvalds
1631da177e4SLinus Torvaldsconfig BSD_PROCESS_ACCT_V3
1641da177e4SLinus Torvalds	bool "BSD Process Accounting version 3 file format"
1651da177e4SLinus Torvalds	depends on BSD_PROCESS_ACCT
1661da177e4SLinus Torvalds	default n
1671da177e4SLinus Torvalds	help
1681da177e4SLinus Torvalds	  If you say Y here, the process accounting information is written
1691da177e4SLinus Torvalds	  in a new file format that also logs the process IDs of each
1701da177e4SLinus Torvalds	  process and it's parent. Note that this file format is incompatible
1711da177e4SLinus Torvalds	  with previous v0/v1/v2 file formats, so you will need updated tools
1721da177e4SLinus Torvalds	  for processing it. A preliminary version of these tools is available
1731da177e4SLinus Torvalds	  at <http://www.physik3.uni-rostock.de/tim/kernel/utils/acct/>.
1741da177e4SLinus Torvalds
175c757249aSShailabh Nagarconfig TASKSTATS
176c757249aSShailabh Nagar	bool "Export task/process statistics through netlink (EXPERIMENTAL)"
177c757249aSShailabh Nagar	depends on NET
178c757249aSShailabh Nagar	default n
179c757249aSShailabh Nagar	help
180c757249aSShailabh Nagar	  Export selected statistics for tasks/processes through the
181c757249aSShailabh Nagar	  generic netlink interface. Unlike BSD process accounting, the
182c757249aSShailabh Nagar	  statistics are available during the lifetime of tasks/processes as
183c757249aSShailabh Nagar	  responses to commands. Like BSD accounting, they are sent to user
184c757249aSShailabh Nagar	  space on task exit.
185c757249aSShailabh Nagar
186c757249aSShailabh Nagar	  Say N if unsure.
187c757249aSShailabh Nagar
188ca74e92bSShailabh Nagarconfig TASK_DELAY_ACCT
189ca74e92bSShailabh Nagar	bool "Enable per-task delay accounting (EXPERIMENTAL)"
1906f44993fSShailabh Nagar	depends on TASKSTATS
191ca74e92bSShailabh Nagar	help
192ca74e92bSShailabh Nagar	  Collect information on time spent by a task waiting for system
193ca74e92bSShailabh Nagar	  resources like cpu, synchronous block I/O completion and swapping
194ca74e92bSShailabh Nagar	  in pages. Such statistics can help in setting a task's priorities
195ca74e92bSShailabh Nagar	  relative to other tasks for cpu, io, rss limits etc.
196ca74e92bSShailabh Nagar
197ca74e92bSShailabh Nagar	  Say N if unsure.
198ca74e92bSShailabh Nagar
19918f705f4SAlexey Dobriyanconfig TASK_XACCT
20018f705f4SAlexey Dobriyan	bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
20118f705f4SAlexey Dobriyan	depends on TASKSTATS
20218f705f4SAlexey Dobriyan	help
20318f705f4SAlexey Dobriyan	  Collect extended task accounting data and send the data
20418f705f4SAlexey Dobriyan	  to userland for processing over the taskstats interface.
20518f705f4SAlexey Dobriyan
20618f705f4SAlexey Dobriyan	  Say N if unsure.
20718f705f4SAlexey Dobriyan
20818f705f4SAlexey Dobriyanconfig TASK_IO_ACCOUNTING
20918f705f4SAlexey Dobriyan	bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
21018f705f4SAlexey Dobriyan	depends on TASK_XACCT
21118f705f4SAlexey Dobriyan	help
21218f705f4SAlexey Dobriyan	  Collect information on the number of bytes of storage I/O which this
21318f705f4SAlexey Dobriyan	  task has caused.
21418f705f4SAlexey Dobriyan
21518f705f4SAlexey Dobriyan	  Say N if unsure.
21618f705f4SAlexey Dobriyan
2171da177e4SLinus Torvaldsconfig AUDIT
2181da177e4SLinus Torvalds	bool "Auditing support"
219804a6a49SChris Wright	depends on NET
2201da177e4SLinus Torvalds	help
2211da177e4SLinus Torvalds	  Enable auditing infrastructure that can be used with another
2221da177e4SLinus Torvalds	  kernel subsystem, such as SELinux (which requires this for
2231da177e4SLinus Torvalds	  logging of avc messages output).  Does not do system-call
2241da177e4SLinus Torvalds	  auditing without CONFIG_AUDITSYSCALL.
2251da177e4SLinus Torvalds
2261da177e4SLinus Torvaldsconfig AUDITSYSCALL
2271da177e4SLinus Torvalds	bool "Enable system-call auditing support"
2281322b9deSYuichi Nakamura	depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64|| SUPERH)
2291da177e4SLinus Torvalds	default y if SECURITY_SELINUX
2301da177e4SLinus Torvalds	help
2311da177e4SLinus Torvalds	  Enable low-overhead system-call auditing infrastructure that
2321da177e4SLinus Torvalds	  can be used independently or with another kernel subsystem,
233f368c07dSAmy Griffis	  such as SELinux.  To use audit's filesystem watch feature, please
234f368c07dSAmy Griffis	  ensure that INOTIFY is configured.
2351da177e4SLinus Torvalds
23674c3cbe3SAl Viroconfig AUDIT_TREE
23774c3cbe3SAl Viro	def_bool y
23874c3cbe3SAl Viro	depends on AUDITSYSCALL && INOTIFY
23974c3cbe3SAl Viro
2401da177e4SLinus Torvaldsconfig IKCONFIG
241f2443ab6SRoss Biro	tristate "Kernel .config support"
2421da177e4SLinus Torvalds	---help---
2431da177e4SLinus Torvalds	  This option enables the complete Linux kernel ".config" file
2441da177e4SLinus Torvalds	  contents to be saved in the kernel. It provides documentation
2451da177e4SLinus Torvalds	  of which kernel options are used in a running kernel or in an
2461da177e4SLinus Torvalds	  on-disk kernel.  This information can be extracted from the kernel
2471da177e4SLinus Torvalds	  image file with the script scripts/extract-ikconfig and used as
2481da177e4SLinus Torvalds	  input to rebuild the current kernel or to build another kernel.
2491da177e4SLinus Torvalds	  It can also be extracted from a running kernel by reading
2501da177e4SLinus Torvalds	  /proc/config.gz if enabled (below).
2511da177e4SLinus Torvalds
2521da177e4SLinus Torvaldsconfig IKCONFIG_PROC
2531da177e4SLinus Torvalds	bool "Enable access to .config through /proc/config.gz"
2541da177e4SLinus Torvalds	depends on IKCONFIG && PROC_FS
2551da177e4SLinus Torvalds	---help---
2561da177e4SLinus Torvalds	  This option enables access to the kernel configuration file
2571da177e4SLinus Torvalds	  through /proc/config.gz.
2581da177e4SLinus Torvalds
259794543a2SAlistair John Strachanconfig LOG_BUF_SHIFT
260794543a2SAlistair John Strachan	int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
261794543a2SAlistair John Strachan	range 12 21
262f17a32e9SAdrian Bunk	default 17
263794543a2SAlistair John Strachan	help
264794543a2SAlistair John Strachan	  Select kernel log buffer size as a power of 2.
265f17a32e9SAdrian Bunk	  Examples:
266f17a32e9SAdrian Bunk	  	     17 => 128 KB
267f17a32e9SAdrian Bunk		     16 => 64 KB
268f17a32e9SAdrian Bunk	             15 => 32 KB
269f17a32e9SAdrian Bunk	             14 => 16 KB
270794543a2SAlistair John Strachan		     13 =>  8 KB
271794543a2SAlistair John Strachan		     12 =>  4 KB
272794543a2SAlistair John Strachan
273ddbcc7e8SPaul Menageconfig CGROUPS
274ddbcc7e8SPaul Menage	bool "Control Group support"
275ddbcc7e8SPaul Menage	help
276ddbcc7e8SPaul Menage	  This option will let you use process cgroup subsystems
277ddbcc7e8SPaul Menage	  such as Cpusets
278ddbcc7e8SPaul Menage
279ddbcc7e8SPaul Menage	  Say N if unsure.
280ddbcc7e8SPaul Menage
281006cb992SPaul Menageconfig CGROUP_DEBUG
282006cb992SPaul Menage	bool "Example debug cgroup subsystem"
283006cb992SPaul Menage	depends on CGROUPS
284418d7d87SPaul Menage	default n
285006cb992SPaul Menage	help
286006cb992SPaul Menage	  This option enables a simple cgroup subsystem that
287006cb992SPaul Menage	  exports useful debugging information about the cgroups
288006cb992SPaul Menage	  framework
289006cb992SPaul Menage
290006cb992SPaul Menage	  Say N if unsure
291006cb992SPaul Menage
292858d72eaSSerge E. Hallynconfig CGROUP_NS
293858d72eaSSerge E. Hallyn        bool "Namespace cgroup subsystem"
294858d72eaSSerge E. Hallyn        depends on CGROUPS
295858d72eaSSerge E. Hallyn        help
296858d72eaSSerge E. Hallyn          Provides a simple namespace cgroup subsystem to
297858d72eaSSerge E. Hallyn          provide hierarchical naming of sets of namespaces,
298858d72eaSSerge E. Hallyn          for instance virtual servers and checkpoint/restart
299858d72eaSSerge E. Hallyn          jobs.
300858d72eaSSerge E. Hallyn
30108ce5f16SSerge E. Hallynconfig CGROUP_DEVICE
30208ce5f16SSerge E. Hallyn	bool "Device controller for cgroups"
30308ce5f16SSerge E. Hallyn	depends on CGROUPS && EXPERIMENTAL
30408ce5f16SSerge E. Hallyn	help
30508ce5f16SSerge E. Hallyn	  Provides a cgroup implementing whitelists for devices which
30608ce5f16SSerge E. Hallyn	  a process in the cgroup can mknod or open.
30708ce5f16SSerge E. Hallyn
3081da177e4SLinus Torvaldsconfig CPUSETS
3091da177e4SLinus Torvalds	bool "Cpuset support"
3108793d854SPaul Menage	depends on SMP && CGROUPS
3111da177e4SLinus Torvalds	help
312d9fd8a6dSRandy Dunlap	  This option will let you create and manage CPUSETs which
3131da177e4SLinus Torvalds	  allow dynamically partitioning a system into sets of CPUs and
3141da177e4SLinus Torvalds	  Memory Nodes and assigning tasks to run only within those sets.
3151da177e4SLinus Torvalds	  This is primarily useful on large SMP or NUMA systems.
3161da177e4SLinus Torvalds
3171da177e4SLinus Torvalds	  Say N if unsure.
3181da177e4SLinus Torvalds
319a5574cf6SIngo Molnar#
320a5574cf6SIngo Molnar# Architectures with an unreliable sched_clock() should select this:
321a5574cf6SIngo Molnar#
322a5574cf6SIngo Molnarconfig HAVE_UNSTABLE_SCHED_CLOCK
323a5574cf6SIngo Molnar	bool
324a5574cf6SIngo Molnar
325052f1dc7SPeter Zijlstraconfig GROUP_SCHED
326052f1dc7SPeter Zijlstra	bool "Group CPU scheduler"
327aac6abcaSParag Warudkar	depends on EXPERIMENTAL
328aac6abcaSParag Warudkar	default n
32929f59db3SSrivatsa Vaddagiri	help
330fb615581SSrivatsa Vaddagiri	  This feature lets CPU scheduler recognize task groups and control CPU
3319b5b7751SSrivatsa Vaddagiri	  bandwidth allocation to such task groups.
33229f59db3SSrivatsa Vaddagiri
333052f1dc7SPeter Zijlstraconfig FAIR_GROUP_SCHED
334052f1dc7SPeter Zijlstra	bool "Group scheduling for SCHED_OTHER"
335052f1dc7SPeter Zijlstra	depends on GROUP_SCHED
336aac6abcaSParag Warudkar	default GROUP_SCHED
33724e377a8SSrivatsa Vaddagiri
338052f1dc7SPeter Zijlstraconfig RT_GROUP_SCHED
339052f1dc7SPeter Zijlstra	bool "Group scheduling for SCHED_RR/FIFO"
340052f1dc7SPeter Zijlstra	depends on EXPERIMENTAL
341052f1dc7SPeter Zijlstra	depends on GROUP_SCHED
342052f1dc7SPeter Zijlstra	default n
343b9b158feSViktor Radnai	help
344b9b158feSViktor Radnai	  This feature lets you explicitly allocate real CPU bandwidth
345b9b158feSViktor Radnai	  to users or control groups (depending on the "Basis for grouping tasks"
346b9b158feSViktor Radnai	  setting below. If enabled, it will also make it impossible to
347b9b158feSViktor Radnai	  schedule realtime tasks for non-root users until you allocate
348b9b158feSViktor Radnai	  realtime bandwidth for them.
349b9b158feSViktor Radnai	  See Documentation/sched-rt-group.txt for more information.
350052f1dc7SPeter Zijlstra
351052f1dc7SPeter Zijlstrachoice
352052f1dc7SPeter Zijlstra	depends on GROUP_SCHED
353052f1dc7SPeter Zijlstra	prompt "Basis for grouping tasks"
354052f1dc7SPeter Zijlstra	default USER_SCHED
355052f1dc7SPeter Zijlstra
356052f1dc7SPeter Zijlstraconfig USER_SCHED
35724e377a8SSrivatsa Vaddagiri	bool "user id"
35824e377a8SSrivatsa Vaddagiri	help
35924e377a8SSrivatsa Vaddagiri	  This option will choose userid as the basis for grouping
360fb615581SSrivatsa Vaddagiri	  tasks, thus providing equal CPU bandwidth to each user.
36124e377a8SSrivatsa Vaddagiri
362052f1dc7SPeter Zijlstraconfig CGROUP_SCHED
36368318b8eSSrivatsa Vaddagiri	bool "Control groups"
36468318b8eSSrivatsa Vaddagiri 	depends on CGROUPS
36568318b8eSSrivatsa Vaddagiri 	help
36668318b8eSSrivatsa Vaddagiri	  This option allows you to create arbitrary task groups
36768318b8eSSrivatsa Vaddagiri	  using the "cgroup" pseudo filesystem and control
36868318b8eSSrivatsa Vaddagiri	  the cpu bandwidth allocated to each such task group.
36968318b8eSSrivatsa Vaddagiri	  Refer to Documentation/cgroups.txt for more information
37068318b8eSSrivatsa Vaddagiri	  on "cgroup" pseudo filesystem.
37168318b8eSSrivatsa Vaddagiri
37224e377a8SSrivatsa Vaddagiriendchoice
37324e377a8SSrivatsa Vaddagiri
374d842de87SSrivatsa Vaddagiriconfig CGROUP_CPUACCT
375d842de87SSrivatsa Vaddagiri	bool "Simple CPU accounting cgroup subsystem"
376d842de87SSrivatsa Vaddagiri	depends on CGROUPS
377d842de87SSrivatsa Vaddagiri	help
378d842de87SSrivatsa Vaddagiri	  Provides a simple Resource Controller for monitoring the
379d842de87SSrivatsa Vaddagiri	  total CPU consumed by the tasks in a cgroup
380d842de87SSrivatsa Vaddagiri
381e552b661SPavel Emelianovconfig RESOURCE_COUNTERS
382e552b661SPavel Emelianov	bool "Resource counters"
383e552b661SPavel Emelianov	help
384e552b661SPavel Emelianov	  This option enables controller independent resource accounting
385e552b661SPavel Emelianov          infrastructure that works with cgroups
386e552b661SPavel Emelianov	depends on CGROUPS
387e552b661SPavel Emelianov
388cf475ad2SBalbir Singhconfig MM_OWNER
389cf475ad2SBalbir Singh	bool
390cf475ad2SBalbir Singh
39100f0b825SBalbir Singhconfig CGROUP_MEM_RES_CTLR
39200f0b825SBalbir Singh	bool "Memory Resource Controller for Control Groups"
39300f0b825SBalbir Singh	depends on CGROUPS && RESOURCE_COUNTERS
394cf475ad2SBalbir Singh	select MM_OWNER
39500f0b825SBalbir Singh	help
39600f0b825SBalbir Singh	  Provides a memory resource controller that manages both page cache and
39700f0b825SBalbir Singh	  RSS memory.
39800f0b825SBalbir Singh
39900f0b825SBalbir Singh	  Note that setting this option increases fixed memory overhead
40000f0b825SBalbir Singh	  associated with each page of memory in the system by 4/8 bytes
40100f0b825SBalbir Singh	  and also increases cache misses because struct page on many 64bit
40200f0b825SBalbir Singh	  systems will not fit into a single cache line anymore.
40300f0b825SBalbir Singh
40400f0b825SBalbir Singh	  Only enable when you're ok with these trade offs and really
40500f0b825SBalbir Singh	  sure you need the memory resource controller.
40600f0b825SBalbir Singh
407cf475ad2SBalbir Singh	  This config option also selects MM_OWNER config option, which
408cf475ad2SBalbir Singh	  could in turn add some fork/exit overhead.
409cf475ad2SBalbir Singh
41088a22c98SKay Sieversconfig SYSFS_DEPRECATED
411d47846c5SIngo Molnar	bool
412d47846c5SIngo Molnar
413d47846c5SIngo Molnarconfig SYSFS_DEPRECATED_V2
41488a22c98SKay Sievers	bool "Create deprecated sysfs files"
4159148fe87SRandy Dunlap	depends on SYSFS
41688a22c98SKay Sievers	default y
417d47846c5SIngo Molnar	select SYSFS_DEPRECATED
41888a22c98SKay Sievers	help
41988a22c98SKay Sievers	  This option creates deprecated symlinks such as the
42088a22c98SKay Sievers	  "device"-link, the <subsystem>:<name>-link, and the
42188a22c98SKay Sievers	  "bus"-link. It may also add deprecated key in the
42288a22c98SKay Sievers	  uevent environment.
42388a22c98SKay Sievers	  None of these features or values should be used today, as
42488a22c98SKay Sievers	  they export driver core implementation details to userspace
42588a22c98SKay Sievers	  or export properties which can't be kept stable across kernel
42688a22c98SKay Sievers	  releases.
42788a22c98SKay Sievers
42888a22c98SKay Sievers	  If enabled, this option will also move any device structures
4293dde6ad8SDavid Sterba	  that belong to a class, back into the /sys/class hierarchy, in
430024440d2SGreg Kroah-Hartman	  order to support older versions of udev and some userspace
431024440d2SGreg Kroah-Hartman	  programs.
43288a22c98SKay Sievers
433024440d2SGreg Kroah-Hartman	  If you are using a distro with the most recent userspace
434024440d2SGreg Kroah-Hartman	  packages, it should be safe to say N here.
43588a22c98SKay Sievers
4368793d854SPaul Menageconfig PROC_PID_CPUSET
4378793d854SPaul Menage	bool "Include legacy /proc/<pid>/cpuset file"
4388793d854SPaul Menage	depends on CPUSETS
4398793d854SPaul Menage	default y
4408793d854SPaul Menage
441b86ff981SJens Axboeconfig RELAY
442b86ff981SJens Axboe	bool "Kernel->user space relay support (formerly relayfs)"
443b86ff981SJens Axboe	help
444b86ff981SJens Axboe	  This option enables support for relay interface support in
445b86ff981SJens Axboe	  certain file systems (such as debugfs).
446b86ff981SJens Axboe	  It is designed to provide an efficient mechanism for tools and
447b86ff981SJens Axboe	  facilities to relay large amounts of data from kernel space to
448b86ff981SJens Axboe	  user space.
449b86ff981SJens Axboe
450b86ff981SJens Axboe	  If unsure, say N.
451b86ff981SJens Axboe
452c5289a69SPavel Emelyanovconfig NAMESPACES
453c5289a69SPavel Emelyanov	bool "Namespaces support" if EMBEDDED
454c5289a69SPavel Emelyanov	default !EMBEDDED
455c5289a69SPavel Emelyanov	help
456c5289a69SPavel Emelyanov	  Provides the way to make tasks work with different objects using
457c5289a69SPavel Emelyanov	  the same id. For example same IPC id may refer to different objects
458c5289a69SPavel Emelyanov	  or same user id or pid may refer to different tasks when used in
459c5289a69SPavel Emelyanov	  different namespaces.
460c5289a69SPavel Emelyanov
46158bfdd6dSPavel Emelyanovconfig UTS_NS
46258bfdd6dSPavel Emelyanov	bool "UTS namespace"
46358bfdd6dSPavel Emelyanov	depends on NAMESPACES
46458bfdd6dSPavel Emelyanov	help
46558bfdd6dSPavel Emelyanov	  In this namespace tasks see different info provided with the
46658bfdd6dSPavel Emelyanov	  uname() system call
46758bfdd6dSPavel Emelyanov
468ae5e1b22SPavel Emelyanovconfig IPC_NS
469ae5e1b22SPavel Emelyanov	bool "IPC namespace"
470ae5e1b22SPavel Emelyanov	depends on NAMESPACES && SYSVIPC
471ae5e1b22SPavel Emelyanov	help
472ae5e1b22SPavel Emelyanov	  In this namespace tasks work with IPC ids which correspond to
473ae5e1b22SPavel Emelyanov	  different IPC objects in different namespaces
474ae5e1b22SPavel Emelyanov
475aee16ce7SPavel Emelyanovconfig USER_NS
476aee16ce7SPavel Emelyanov	bool "User namespace (EXPERIMENTAL)"
477aee16ce7SPavel Emelyanov	depends on NAMESPACES && EXPERIMENTAL
478aee16ce7SPavel Emelyanov	help
479aee16ce7SPavel Emelyanov	  This allows containers, i.e. vservers, to use user namespaces
480aee16ce7SPavel Emelyanov	  to provide different user info for different servers.
481aee16ce7SPavel Emelyanov	  If unsure, say N.
482aee16ce7SPavel Emelyanov
48374bd59bbSPavel Emelyanovconfig PID_NS
48474bd59bbSPavel Emelyanov	bool "PID Namespaces (EXPERIMENTAL)"
48574bd59bbSPavel Emelyanov	default n
48674bd59bbSPavel Emelyanov	depends on NAMESPACES && EXPERIMENTAL
48774bd59bbSPavel Emelyanov	help
48874bd59bbSPavel Emelyanov	  Suport process id namespaces.  This allows having multiple
48974bd59bbSPavel Emelyanov	  process with the same pid as long as they are in different
49074bd59bbSPavel Emelyanov	  pid namespaces.  This is a building block of containers.
49174bd59bbSPavel Emelyanov
49274bd59bbSPavel Emelyanov	  Unless you want to work with an experimental feature
49374bd59bbSPavel Emelyanov	  say N here.
49474bd59bbSPavel Emelyanov
495f991633dSDimitri Gorokhovikconfig BLK_DEV_INITRD
496f991633dSDimitri Gorokhovik	bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
497f991633dSDimitri Gorokhovik	depends on BROKEN || !FRV
498f991633dSDimitri Gorokhovik	help
499f991633dSDimitri Gorokhovik	  The initial RAM filesystem is a ramfs which is loaded by the
500f991633dSDimitri Gorokhovik	  boot loader (loadlin or lilo) and that is mounted as root
501f991633dSDimitri Gorokhovik	  before the normal boot procedure. It is typically used to
502f991633dSDimitri Gorokhovik	  load modules needed to mount the "real" root file system,
503f991633dSDimitri Gorokhovik	  etc. See <file:Documentation/initrd.txt> for details.
504f991633dSDimitri Gorokhovik
505f991633dSDimitri Gorokhovik	  If RAM disk support (BLK_DEV_RAM) is also included, this
506f991633dSDimitri Gorokhovik	  also enables initial RAM disk (initrd) support and adds
507f991633dSDimitri Gorokhovik	  15 Kbytes (more on some other architectures) to the kernel size.
508f991633dSDimitri Gorokhovik
509f991633dSDimitri Gorokhovik	  If unsure say Y.
510f991633dSDimitri Gorokhovik
511c33df4eaSJean-Paul Samanif BLK_DEV_INITRD
512c33df4eaSJean-Paul Saman
513dbec4866SSam Ravnborgsource "usr/Kconfig"
514dbec4866SSam Ravnborg
515c33df4eaSJean-Paul Samanendif
516c33df4eaSJean-Paul Saman
517c45b4f1fSLinus Torvaldsconfig CC_OPTIMIZE_FOR_SIZE
51896fffeb4SIngo Molnar	bool "Optimize for size"
519c45b4f1fSLinus Torvalds	default y
520c45b4f1fSLinus Torvalds	help
521c45b4f1fSLinus Torvalds	  Enabling this option will pass "-Os" instead of "-O2" to gcc
522c45b4f1fSLinus Torvalds	  resulting in a smaller kernel.
523c45b4f1fSLinus Torvalds
524c45b4f1fSLinus Torvalds	  If unsure, say N.
525c45b4f1fSLinus Torvalds
5260847062aSRandy Dunlapconfig SYSCTL
5270847062aSRandy Dunlap	bool
5280847062aSRandy Dunlap
5291da177e4SLinus Torvaldsmenuconfig EMBEDDED
5301da177e4SLinus Torvalds	bool "Configure standard kernel features (for small systems)"
5311da177e4SLinus Torvalds	help
5321da177e4SLinus Torvalds	  This option allows certain base kernel options and settings
5331da177e4SLinus Torvalds          to be disabled or tweaked. This is for specialized
5341da177e4SLinus Torvalds          environments which can tolerate a "non-standard" kernel.
5351da177e4SLinus Torvalds          Only use this if you really know what you are doing.
5361da177e4SLinus Torvalds
537ae81f9e3SChuck Ebbertconfig UID16
538ae81f9e3SChuck Ebbert	bool "Enable 16-bit UID system calls" if EMBEDDED
53909337f50SDavid S. Miller	depends on ARM || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && COMPAT) || UML || (X86_64 && IA32_EMULATION)
540ae81f9e3SChuck Ebbert	default y
541ae81f9e3SChuck Ebbert	help
542ae81f9e3SChuck Ebbert	  This enables the legacy 16-bit UID syscall wrappers.
543ae81f9e3SChuck Ebbert
544b89a8171SEric W. Biedermanconfig SYSCTL_SYSCALL
5450847062aSRandy Dunlap	bool "Sysctl syscall support" if EMBEDDED
54613bb7e37SEric W. Biederman	default y
547b89a8171SEric W. Biederman	select SYSCTL
548b89a8171SEric W. Biederman	---help---
54913bb7e37SEric W. Biederman	  sys_sysctl uses binary paths that have been found challenging
55013bb7e37SEric W. Biederman	  to properly maintain and use.  The interface in /proc/sys
55113bb7e37SEric W. Biederman	  using paths with ascii names is now the primary path to this
55213bb7e37SEric W. Biederman	  information.
553b89a8171SEric W. Biederman
55413bb7e37SEric W. Biederman	  Almost nothing using the binary sysctl interface so if you are
55513bb7e37SEric W. Biederman	  trying to save some space it is probably safe to disable this,
55613bb7e37SEric W. Biederman	  making your kernel marginally smaller.
557b89a8171SEric W. Biederman
55813bb7e37SEric W. Biederman	  If unsure say Y here.
559ae81f9e3SChuck Ebbert
56088f458e4SHolger Schurigconfig SYSCTL_SYSCALL_CHECK
56188f458e4SHolger Schurig	bool "Sysctl checks" if EMBEDDED
56288f458e4SHolger Schurig	depends on SYSCTL_SYSCALL
56388f458e4SHolger Schurig	default y
56488f458e4SHolger Schurig	---help---
56588f458e4SHolger Schurig	  sys_sysctl uses binary paths that have been found challenging
56688f458e4SHolger Schurig	  to properly maintain and use. This enables checks that help
56788f458e4SHolger Schurig	  you to keep things correct.
56888f458e4SHolger Schurig
56988f458e4SHolger Schurig	  If unsure say Y here.
57088f458e4SHolger Schurig
5711da177e4SLinus Torvaldsconfig KALLSYMS
572979c6a1eSJesper Juhl	 bool "Load all symbols for debugging/ksymoops" if EMBEDDED
5731da177e4SLinus Torvalds	 default y
5741da177e4SLinus Torvalds	 help
5751da177e4SLinus Torvalds	   Say Y here to let the kernel print out symbolic crash information and
5761da177e4SLinus Torvalds	   symbolic stack backtraces. This increases the size of the kernel
5771da177e4SLinus Torvalds	   somewhat, as all symbols have to be loaded into the kernel image.
5781da177e4SLinus Torvalds
5791da177e4SLinus Torvaldsconfig KALLSYMS_ALL
5801da177e4SLinus Torvalds	bool "Include all symbols in kallsyms"
5811da177e4SLinus Torvalds	depends on DEBUG_KERNEL && KALLSYMS
5821da177e4SLinus Torvalds	help
5831da177e4SLinus Torvalds	   Normally kallsyms only contains the symbols of functions, for nicer
5841da177e4SLinus Torvalds	   OOPS messages.  Some debuggers can use kallsyms for other
585f9f97bc0SJesper Juhl	   symbols too: say Y here to include all symbols, if you need them
586f9f97bc0SJesper Juhl	   and you don't care about adding 300k to the size of your kernel.
5871da177e4SLinus Torvalds
5881da177e4SLinus Torvalds	   Say N.
5891da177e4SLinus Torvalds
5901da177e4SLinus Torvaldsconfig KALLSYMS_EXTRA_PASS
5911da177e4SLinus Torvalds	bool "Do an extra kallsyms pass"
5921da177e4SLinus Torvalds	depends on KALLSYMS
5931da177e4SLinus Torvalds	help
5941da177e4SLinus Torvalds	   If kallsyms is not working correctly, the build will fail with
5951da177e4SLinus Torvalds	   inconsistent kallsyms data.  If that occurs, log a bug report and
5961da177e4SLinus Torvalds	   turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
5971da177e4SLinus Torvalds	   Always say N here unless you find a bug in kallsyms, which must be
5981da177e4SLinus Torvalds	   reported.  KALLSYMS_EXTRA_PASS is only a temporary workaround while
5991da177e4SLinus Torvalds	   you wait for kallsyms to be fixed.
6001da177e4SLinus Torvalds
601d59745ceSMatt Mackall
602712f47ceSGreg Kroah-Hartmanconfig HOTPLUG
603712f47ceSGreg Kroah-Hartman	bool "Support for hot-pluggable devices" if EMBEDDED
604712f47ceSGreg Kroah-Hartman	default y
605712f47ceSGreg Kroah-Hartman	help
606712f47ceSGreg Kroah-Hartman	  This option is provided for the case where no hotplug or uevent
607712f47ceSGreg Kroah-Hartman	  capabilities is wanted by the kernel.  You should only consider
608712f47ceSGreg Kroah-Hartman	  disabling this option for embedded systems that do not use modules, a
609712f47ceSGreg Kroah-Hartman	  dynamic /dev tree, or dynamic device discovery.  Just say Y.
610712f47ceSGreg Kroah-Hartman
611d59745ceSMatt Mackallconfig PRINTK
612d59745ceSMatt Mackall	default y
613d59745ceSMatt Mackall	bool "Enable support for printk" if EMBEDDED
614d59745ceSMatt Mackall	help
615d59745ceSMatt Mackall	  This option enables normal printk support. Removing it
616d59745ceSMatt Mackall	  eliminates most of the message strings from the kernel image
617d59745ceSMatt Mackall	  and makes the kernel more or less silent. As this makes it
618d59745ceSMatt Mackall	  very difficult to diagnose system problems, saying N here is
619d59745ceSMatt Mackall	  strongly discouraged.
620d59745ceSMatt Mackall
621c8538a7aSMatt Mackallconfig BUG
622c8538a7aSMatt Mackall	bool "BUG() support" if EMBEDDED
623c8538a7aSMatt Mackall	default y
624c8538a7aSMatt Mackall	help
625c8538a7aSMatt Mackall          Disabling this option eliminates support for BUG and WARN, reducing
626c8538a7aSMatt Mackall          the size of your kernel image and potentially quietly ignoring
627c8538a7aSMatt Mackall          numerous fatal conditions. You should only consider disabling this
628c8538a7aSMatt Mackall          option for embedded systems with no facilities for reporting errors.
629c8538a7aSMatt Mackall          Just say Y.
630c8538a7aSMatt Mackall
631708e9a79SMatt Mackallconfig ELF_CORE
632708e9a79SMatt Mackall	default y
633708e9a79SMatt Mackall	bool "Enable ELF core dumps" if EMBEDDED
634708e9a79SMatt Mackall	help
635708e9a79SMatt Mackall	  Enable support for generating core dumps. Disabling saves about 4k.
636708e9a79SMatt Mackall
637*e5e1d3cbSStas Sergeevconfig PCSPKR_PLATFORM
638*e5e1d3cbSStas Sergeev	bool "Enable PC-Speaker support" if EMBEDDED
639*e5e1d3cbSStas Sergeev	depends on ALPHA || X86 || MIPS || PPC_PREP || PPC_CHRP || PPC_PSERIES
640*e5e1d3cbSStas Sergeev	default y
641*e5e1d3cbSStas Sergeev	help
642*e5e1d3cbSStas Sergeev          This option allows to disable the internal PC-Speaker
643*e5e1d3cbSStas Sergeev          support, saving some memory.
644*e5e1d3cbSStas Sergeev
64532a93233SIngo Molnarconfig COMPAT_BRK
64632a93233SIngo Molnar	bool "Disable heap randomization"
64732a93233SIngo Molnar	default y
64832a93233SIngo Molnar	help
64932a93233SIngo Molnar	  Randomizing heap placement makes heap exploits harder, but it
65032a93233SIngo Molnar	  also breaks ancient binaries (including anything libc5 based).
65132a93233SIngo Molnar	  This option changes the bootup default to heap randomization
65232a93233SIngo Molnar	  disabled, and can be overriden runtime by setting
65332a93233SIngo Molnar	  /proc/sys/kernel/randomize_va_space to 2.
65432a93233SIngo Molnar
655166124fdSIngo Molnar	  On non-ancient distros (post-2000 ones) N is usually a safe choice.
65632a93233SIngo Molnar
6571da177e4SLinus Torvaldsconfig BASE_FULL
6581da177e4SLinus Torvalds	default y
6591da177e4SLinus Torvalds	bool "Enable full-sized data structures for core" if EMBEDDED
6601da177e4SLinus Torvalds	help
6611da177e4SLinus Torvalds	  Disabling this option reduces the size of miscellaneous core
6621da177e4SLinus Torvalds	  kernel data structures. This saves memory on small machines,
6631da177e4SLinus Torvalds	  but may reduce performance.
6641da177e4SLinus Torvalds
6651da177e4SLinus Torvaldsconfig FUTEX
6661da177e4SLinus Torvalds	bool "Enable futex support" if EMBEDDED
6671da177e4SLinus Torvalds	default y
66823f78d4aSIngo Molnar	select RT_MUTEXES
6691da177e4SLinus Torvalds	help
6701da177e4SLinus Torvalds	  Disabling this option will cause the kernel to be built without
6711da177e4SLinus Torvalds	  support for "fast userspace mutexes".  The resulting kernel may not
6721da177e4SLinus Torvalds	  run glibc-based applications correctly.
6731da177e4SLinus Torvalds
6745dc8bf81SDavide Libenziconfig ANON_INODES
675448e3ceeSAdrian Bunk	bool
6765dc8bf81SDavide Libenzi
6771da177e4SLinus Torvaldsconfig EPOLL
6781da177e4SLinus Torvalds	bool "Enable eventpoll support" if EMBEDDED
6791da177e4SLinus Torvalds	default y
680448e3ceeSAdrian Bunk	select ANON_INODES
6811da177e4SLinus Torvalds	help
6821da177e4SLinus Torvalds	  Disabling this option will cause the kernel to be built without
6831da177e4SLinus Torvalds	  support for epoll family of system calls.
6841da177e4SLinus Torvalds
685fba2afaaSDavide Libenziconfig SIGNALFD
686fba2afaaSDavide Libenzi	bool "Enable signalfd() system call" if EMBEDDED
687448e3ceeSAdrian Bunk	select ANON_INODES
688fba2afaaSDavide Libenzi	default y
689fba2afaaSDavide Libenzi	help
690fba2afaaSDavide Libenzi	  Enable the signalfd() system call that allows to receive signals
691fba2afaaSDavide Libenzi	  on a file descriptor.
692fba2afaaSDavide Libenzi
693fba2afaaSDavide Libenzi	  If unsure, say Y.
694fba2afaaSDavide Libenzi
695b215e283SDavide Libenziconfig TIMERFD
696b215e283SDavide Libenzi	bool "Enable timerfd() system call" if EMBEDDED
697448e3ceeSAdrian Bunk	select ANON_INODES
698b215e283SDavide Libenzi	default y
699b215e283SDavide Libenzi	help
700b215e283SDavide Libenzi	  Enable the timerfd() system call that allows to receive timer
701b215e283SDavide Libenzi	  events on a file descriptor.
702b215e283SDavide Libenzi
703b215e283SDavide Libenzi	  If unsure, say Y.
704b215e283SDavide Libenzi
705e1ad7468SDavide Libenziconfig EVENTFD
706e1ad7468SDavide Libenzi	bool "Enable eventfd() system call" if EMBEDDED
707448e3ceeSAdrian Bunk	select ANON_INODES
708e1ad7468SDavide Libenzi	default y
709e1ad7468SDavide Libenzi	help
710e1ad7468SDavide Libenzi	  Enable the eventfd() system call that allows to receive both
711e1ad7468SDavide Libenzi	  kernel notification (ie. KAIO) or userspace notifications.
712e1ad7468SDavide Libenzi
713e1ad7468SDavide Libenzi	  If unsure, say Y.
714e1ad7468SDavide Libenzi
7151da177e4SLinus Torvaldsconfig SHMEM
7161da177e4SLinus Torvalds	bool "Use full shmem filesystem" if EMBEDDED
7171da177e4SLinus Torvalds	default y
7181da177e4SLinus Torvalds	depends on MMU
7191da177e4SLinus Torvalds	help
7201da177e4SLinus Torvalds	  The shmem is an internal filesystem used to manage shared memory.
7211da177e4SLinus Torvalds	  It is backed by swap and manages resource limits. It is also exported
7221da177e4SLinus Torvalds	  to userspace as tmpfs if TMPFS is enabled. Disabling this
7231da177e4SLinus Torvalds	  option replaces shmem and tmpfs with the much simpler ramfs code,
7241da177e4SLinus Torvalds	  which may be appropriate on small systems without swap.
7251da177e4SLinus Torvalds
726f8891e5eSChristoph Lameterconfig VM_EVENT_COUNTERS
727f8891e5eSChristoph Lameter	default y
728f8891e5eSChristoph Lameter	bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
729f8891e5eSChristoph Lameter	help
7302aea4fb6SPaul Jackson	  VM event counters are needed for event counts to be shown.
7312aea4fb6SPaul Jackson	  This option allows the disabling of the VM event counters
7322aea4fb6SPaul Jackson	  on EMBEDDED systems.  /proc/vmstat will only show page counts
7332aea4fb6SPaul Jackson	  if VM event counters are disabled.
734f8891e5eSChristoph Lameter
73541ecc55bSChristoph Lameterconfig SLUB_DEBUG
73641ecc55bSChristoph Lameter	default y
73741ecc55bSChristoph Lameter	bool "Enable SLUB debugging support" if EMBEDDED
738f6acb635SChristoph Lameter	depends on SLUB && SYSFS
73941ecc55bSChristoph Lameter	help
74041ecc55bSChristoph Lameter	  SLUB has extensive debug support features. Disabling these can
74141ecc55bSChristoph Lameter	  result in significant savings in code size. This also disables
74241ecc55bSChristoph Lameter	  SLUB sysfs support. /sys/slab will not exist and there will be
74341ecc55bSChristoph Lameter	  no support for cache validation etc.
74441ecc55bSChristoph Lameter
74581819f0fSChristoph Lameterchoice
74681819f0fSChristoph Lameter	prompt "Choose SLAB allocator"
747a0acd820SChristoph Lameter	default SLUB
74881819f0fSChristoph Lameter	help
74981819f0fSChristoph Lameter	   This option allows to select a slab allocator.
75081819f0fSChristoph Lameter
75181819f0fSChristoph Lameterconfig SLAB
75281819f0fSChristoph Lameter	bool "SLAB"
75381819f0fSChristoph Lameter	help
75481819f0fSChristoph Lameter	  The regular slab allocator that is established and known to work
75534013886SChristoph Lameter	  well in all environments. It organizes cache hot objects in
75681819f0fSChristoph Lameter	  per cpu and per node queues. SLAB is the default choice for
75734013886SChristoph Lameter	  a slab allocator.
75881819f0fSChristoph Lameter
75981819f0fSChristoph Lameterconfig SLUB
76081819f0fSChristoph Lameter	bool "SLUB (Unqueued Allocator)"
76181819f0fSChristoph Lameter	help
76281819f0fSChristoph Lameter	   SLUB is a slab allocator that minimizes cache line usage
76381819f0fSChristoph Lameter	   instead of managing queues of cached objects (SLAB approach).
76481819f0fSChristoph Lameter	   Per cpu caching is realized using slabs of objects instead
76581819f0fSChristoph Lameter	   of queues of objects. SLUB can use memory efficiently
76634013886SChristoph Lameter	   and has enhanced diagnostics.
76781819f0fSChristoph Lameter
76881819f0fSChristoph Lameterconfig SLOB
76984a01c2fSPaul Mundt	depends on EMBEDDED
77081819f0fSChristoph Lameter	bool "SLOB (Simple Allocator)"
77181819f0fSChristoph Lameter	help
77237291458SMatt Mackall	   SLOB replaces the stock allocator with a drastically simpler
77337291458SMatt Mackall	   allocator. SLOB is generally more space efficient but
77437291458SMatt Mackall	   does not perform as well on large systems.
77581819f0fSChristoph Lameter
77681819f0fSChristoph Lameterendchoice
77781819f0fSChristoph Lameter
778125e5645SMathieu Desnoyersconfig PROFILING
779125e5645SMathieu Desnoyers	bool "Profiling support (EXPERIMENTAL)"
780125e5645SMathieu Desnoyers	help
781125e5645SMathieu Desnoyers	  Say Y here to enable the extended profiling support mechanisms used
782125e5645SMathieu Desnoyers	  by profilers such as OProfile.
783125e5645SMathieu Desnoyers
784125e5645SMathieu Desnoyersconfig MARKERS
785125e5645SMathieu Desnoyers	bool "Activate markers"
786125e5645SMathieu Desnoyers	help
787125e5645SMathieu Desnoyers	  Place an empty function call at each marker site. Can be
788125e5645SMathieu Desnoyers	  dynamically changed for a probe function.
789125e5645SMathieu Desnoyers
790fb32e03fSMathieu Desnoyerssource "arch/Kconfig"
791fb32e03fSMathieu Desnoyers
7921e883281SMatt Mackallconfig PROC_PAGE_MONITOR
7931e883281SMatt Mackall 	default y
7941e883281SMatt Mackall	depends on PROC_FS && MMU
7951e883281SMatt Mackall	bool "Enable /proc page monitoring" if EMBEDDED
7961e883281SMatt Mackall 	help
7971e883281SMatt Mackall	  Various /proc files exist to monitor process memory utilization:
7981e883281SMatt Mackall	  /proc/pid/smaps, /proc/pid/clear_refs, /proc/pid/pagemap,
7991e883281SMatt Mackall	  /proc/kpagecount, and /proc/kpageflags. Disabling these
8001e883281SMatt Mackall          interfaces will reduce the size of the kernel by approximately 4kb.
8011e883281SMatt Mackall
8021da177e4SLinus Torvaldsendmenu		# General setup
8031da177e4SLinus Torvalds
804158a9624SLinus Torvaldsconfig SLABINFO
805158a9624SLinus Torvalds	bool
806158a9624SLinus Torvalds	depends on PROC_FS
8070f389ec6SChristoph Lameter	depends on SLAB || SLUB_DEBUG
808158a9624SLinus Torvalds	default y
809158a9624SLinus Torvalds
810ae81f9e3SChuck Ebbertconfig RT_MUTEXES
811ae81f9e3SChuck Ebbert	boolean
812ae81f9e3SChuck Ebbert	select PLIST
813ae81f9e3SChuck Ebbert
8141da177e4SLinus Torvaldsconfig TINY_SHMEM
8151da177e4SLinus Torvalds	default !SHMEM
8161da177e4SLinus Torvalds	bool
8171da177e4SLinus Torvalds
8181da177e4SLinus Torvaldsconfig BASE_SMALL
8191da177e4SLinus Torvalds	int
8201da177e4SLinus Torvalds	default 0 if BASE_FULL
8211da177e4SLinus Torvalds	default 1 if !BASE_FULL
8221da177e4SLinus Torvalds
82366da5733SJan Engelhardtmenuconfig MODULES
8241da177e4SLinus Torvalds	bool "Enable loadable module support"
8251da177e4SLinus Torvalds	help
8261da177e4SLinus Torvalds	  Kernel modules are small pieces of compiled code which can
8271da177e4SLinus Torvalds	  be inserted in the running kernel, rather than being
8281da177e4SLinus Torvalds	  permanently built into the kernel.  You use the "modprobe"
8291da177e4SLinus Torvalds	  tool to add (and sometimes remove) them.  If you say Y here,
8301da177e4SLinus Torvalds	  many parts of the kernel can be built as modules (by
8311da177e4SLinus Torvalds	  answering M instead of Y where indicated): this is most
8321da177e4SLinus Torvalds	  useful for infrequently used options which are not required
8331da177e4SLinus Torvalds	  for booting.  For more information, see the man pages for
8341da177e4SLinus Torvalds	  modprobe, lsmod, modinfo, insmod and rmmod.
8351da177e4SLinus Torvalds
8361da177e4SLinus Torvalds	  If you say Y here, you will need to run "make
8371da177e4SLinus Torvalds	  modules_install" to put the modules under /lib/modules/
8381da177e4SLinus Torvalds	  where modprobe can find them (you may need to be root to do
8391da177e4SLinus Torvalds	  this).
8401da177e4SLinus Torvalds
8411da177e4SLinus Torvalds	  If unsure, say Y.
8421da177e4SLinus Torvalds
843826e4506SLinus Torvaldsconfig MODULE_FORCE_LOAD
844826e4506SLinus Torvalds	bool "Forced module loading"
845826e4506SLinus Torvalds	depends on MODULES
846826e4506SLinus Torvalds	default n
847826e4506SLinus Torvalds	help
848826e4506SLinus Torvalds	  This option allows loading of modules even if that would set the
849826e4506SLinus Torvalds          'F' (forced) taint, due to lack of version info.  Which is
850826e4506SLinus Torvalds	  usually a really bad idea.
851826e4506SLinus Torvalds
8521da177e4SLinus Torvaldsconfig MODULE_UNLOAD
8531da177e4SLinus Torvalds	bool "Module unloading"
8541da177e4SLinus Torvalds	depends on MODULES
8551da177e4SLinus Torvalds	help
8561da177e4SLinus Torvalds	  Without this option you will not be able to unload any
8571da177e4SLinus Torvalds	  modules (note that some modules may not be unloadable
8581da177e4SLinus Torvalds	  anyway), which makes your kernel slightly smaller and
8591da177e4SLinus Torvalds	  simpler.  If unsure, say Y.
8601da177e4SLinus Torvalds
8611da177e4SLinus Torvaldsconfig MODULE_FORCE_UNLOAD
8621da177e4SLinus Torvalds	bool "Forced module unloading"
8631da177e4SLinus Torvalds	depends on MODULE_UNLOAD && EXPERIMENTAL
8641da177e4SLinus Torvalds	help
8651da177e4SLinus Torvalds	  This option allows you to force a module to unload, even if the
8661da177e4SLinus Torvalds	  kernel believes it is unsafe: the kernel will remove the module
8671da177e4SLinus Torvalds	  without waiting for anyone to stop using it (using the -f option to
8681da177e4SLinus Torvalds	  rmmod).  This is mainly for kernel developers and desperate users.
8691da177e4SLinus Torvalds	  If unsure, say N.
8701da177e4SLinus Torvalds
8711da177e4SLinus Torvaldsconfig MODVERSIONS
8720d541643SSam Ravnborg	bool "Module versioning support"
8730d541643SSam Ravnborg	depends on MODULES
8741da177e4SLinus Torvalds	help
8751da177e4SLinus Torvalds	  Usually, you have to use modules compiled with your kernel.
8761da177e4SLinus Torvalds	  Saying Y here makes it sometimes possible to use modules
8771da177e4SLinus Torvalds	  compiled for different kernels, by adding enough information
8781da177e4SLinus Torvalds	  to the modules to (hopefully) spot any changes which would
8791da177e4SLinus Torvalds	  make them incompatible with the kernel you are running.  If
8801da177e4SLinus Torvalds	  unsure, say N.
8811da177e4SLinus Torvalds
8821da177e4SLinus Torvaldsconfig MODULE_SRCVERSION_ALL
8831da177e4SLinus Torvalds	bool "Source checksum for all modules"
8841da177e4SLinus Torvalds	depends on MODULES
8851da177e4SLinus Torvalds	help
8861da177e4SLinus Torvalds	  Modules which contain a MODULE_VERSION get an extra "srcversion"
8871da177e4SLinus Torvalds	  field inserted into their modinfo section, which contains a
8881da177e4SLinus Torvalds    	  sum of the source files which made it.  This helps maintainers
8891da177e4SLinus Torvalds	  see exactly which source was used to build a module (since
8901da177e4SLinus Torvalds	  others sometimes change the module source without updating
8911da177e4SLinus Torvalds	  the version).  With this option, such a "srcversion" field
8921da177e4SLinus Torvalds	  will be created for all modules.  If unsure, say N.
8931da177e4SLinus Torvalds
8941da177e4SLinus Torvaldsconfig KMOD
8951da177e4SLinus Torvalds	bool "Automatic kernel module loading"
8961da177e4SLinus Torvalds	depends on MODULES
8971da177e4SLinus Torvalds	help
8981da177e4SLinus Torvalds	  Normally when you have selected some parts of the kernel to
8991da177e4SLinus Torvalds	  be created as kernel modules, you must load them (using the
9001da177e4SLinus Torvalds	  "modprobe" command) before you can use them. If you say Y
9011da177e4SLinus Torvalds	  here, some parts of the kernel will be able to load modules
9021da177e4SLinus Torvalds	  automatically: when a part of the kernel needs a module, it
9031da177e4SLinus Torvalds	  runs modprobe with the appropriate arguments, thereby
9041da177e4SLinus Torvalds	  loading the module if it is available.  If unsure, say Y.
9051da177e4SLinus Torvalds
9061da177e4SLinus Torvaldsconfig STOP_MACHINE
9071da177e4SLinus Torvalds	bool
9081da177e4SLinus Torvalds	default y
9091da177e4SLinus Torvalds	depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
9101da177e4SLinus Torvalds	help
9111da177e4SLinus Torvalds	  Need stop_machine() primitive.
9123a65dfe8SJens Axboe
9133a65dfe8SJens Axboesource "block/Kconfig"
914e98c3202SAvi Kivity
915e98c3202SAvi Kivityconfig PREEMPT_NOTIFIERS
916e98c3202SAvi Kivity	bool
917e260be67SPaul E. McKenney
918e260be67SPaul E. McKenneyconfig CLASSIC_RCU
91921bbb39cSPaul E. McKenney	def_bool !PREEMPT_RCU
920e260be67SPaul E. McKenney	help
921e260be67SPaul E. McKenney	  This option selects the classic RCU implementation that is
922e260be67SPaul E. McKenney	  designed for best read-side performance on non-realtime
92321bbb39cSPaul E. McKenney	  systems.  Classic RCU is the default.  Note that the
92421bbb39cSPaul E. McKenney	  PREEMPT_RCU symbol is used to select/deselect this option.
925