xref: /openbmc/linux/init/Kconfig (revision 88f458e4)
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
319052f1dc7SPeter Zijlstraconfig GROUP_SCHED
320052f1dc7SPeter Zijlstra	bool "Group CPU scheduler"
321de8d585aSIngo Molnar	default y
32229f59db3SSrivatsa Vaddagiri	help
323fb615581SSrivatsa Vaddagiri	  This feature lets CPU scheduler recognize task groups and control CPU
3249b5b7751SSrivatsa Vaddagiri	  bandwidth allocation to such task groups.
32529f59db3SSrivatsa Vaddagiri
326052f1dc7SPeter Zijlstraconfig FAIR_GROUP_SCHED
327052f1dc7SPeter Zijlstra	bool "Group scheduling for SCHED_OTHER"
328052f1dc7SPeter Zijlstra	depends on GROUP_SCHED
329052f1dc7SPeter Zijlstra	default y
33024e377a8SSrivatsa Vaddagiri
331052f1dc7SPeter Zijlstraconfig RT_GROUP_SCHED
332052f1dc7SPeter Zijlstra	bool "Group scheduling for SCHED_RR/FIFO"
333052f1dc7SPeter Zijlstra	depends on EXPERIMENTAL
334052f1dc7SPeter Zijlstra	depends on GROUP_SCHED
335052f1dc7SPeter Zijlstra	default n
336b9b158feSViktor Radnai	help
337b9b158feSViktor Radnai	  This feature lets you explicitly allocate real CPU bandwidth
338b9b158feSViktor Radnai	  to users or control groups (depending on the "Basis for grouping tasks"
339b9b158feSViktor Radnai	  setting below. If enabled, it will also make it impossible to
340b9b158feSViktor Radnai	  schedule realtime tasks for non-root users until you allocate
341b9b158feSViktor Radnai	  realtime bandwidth for them.
342b9b158feSViktor Radnai	  See Documentation/sched-rt-group.txt for more information.
343052f1dc7SPeter Zijlstra
344052f1dc7SPeter Zijlstrachoice
345052f1dc7SPeter Zijlstra	depends on GROUP_SCHED
346052f1dc7SPeter Zijlstra	prompt "Basis for grouping tasks"
347052f1dc7SPeter Zijlstra	default USER_SCHED
348052f1dc7SPeter Zijlstra
349052f1dc7SPeter Zijlstraconfig USER_SCHED
35024e377a8SSrivatsa Vaddagiri	bool "user id"
35124e377a8SSrivatsa Vaddagiri	help
35224e377a8SSrivatsa Vaddagiri	  This option will choose userid as the basis for grouping
353fb615581SSrivatsa Vaddagiri	  tasks, thus providing equal CPU bandwidth to each user.
35424e377a8SSrivatsa Vaddagiri
355052f1dc7SPeter Zijlstraconfig CGROUP_SCHED
35668318b8eSSrivatsa Vaddagiri	bool "Control groups"
35768318b8eSSrivatsa Vaddagiri 	depends on CGROUPS
35868318b8eSSrivatsa Vaddagiri 	help
35968318b8eSSrivatsa Vaddagiri	  This option allows you to create arbitrary task groups
36068318b8eSSrivatsa Vaddagiri	  using the "cgroup" pseudo filesystem and control
36168318b8eSSrivatsa Vaddagiri	  the cpu bandwidth allocated to each such task group.
36268318b8eSSrivatsa Vaddagiri	  Refer to Documentation/cgroups.txt for more information
36368318b8eSSrivatsa Vaddagiri	  on "cgroup" pseudo filesystem.
36468318b8eSSrivatsa Vaddagiri
36524e377a8SSrivatsa Vaddagiriendchoice
36624e377a8SSrivatsa Vaddagiri
367d842de87SSrivatsa Vaddagiriconfig CGROUP_CPUACCT
368d842de87SSrivatsa Vaddagiri	bool "Simple CPU accounting cgroup subsystem"
369d842de87SSrivatsa Vaddagiri	depends on CGROUPS
370d842de87SSrivatsa Vaddagiri	help
371d842de87SSrivatsa Vaddagiri	  Provides a simple Resource Controller for monitoring the
372d842de87SSrivatsa Vaddagiri	  total CPU consumed by the tasks in a cgroup
373d842de87SSrivatsa Vaddagiri
374e552b661SPavel Emelianovconfig RESOURCE_COUNTERS
375e552b661SPavel Emelianov	bool "Resource counters"
376e552b661SPavel Emelianov	help
377e552b661SPavel Emelianov	  This option enables controller independent resource accounting
378e552b661SPavel Emelianov          infrastructure that works with cgroups
379e552b661SPavel Emelianov	depends on CGROUPS
380e552b661SPavel Emelianov
381cf475ad2SBalbir Singhconfig MM_OWNER
382cf475ad2SBalbir Singh	bool
383cf475ad2SBalbir Singh
38400f0b825SBalbir Singhconfig CGROUP_MEM_RES_CTLR
38500f0b825SBalbir Singh	bool "Memory Resource Controller for Control Groups"
38600f0b825SBalbir Singh	depends on CGROUPS && RESOURCE_COUNTERS
387cf475ad2SBalbir Singh	select MM_OWNER
38800f0b825SBalbir Singh	help
38900f0b825SBalbir Singh	  Provides a memory resource controller that manages both page cache and
39000f0b825SBalbir Singh	  RSS memory.
39100f0b825SBalbir Singh
39200f0b825SBalbir Singh	  Note that setting this option increases fixed memory overhead
39300f0b825SBalbir Singh	  associated with each page of memory in the system by 4/8 bytes
39400f0b825SBalbir Singh	  and also increases cache misses because struct page on many 64bit
39500f0b825SBalbir Singh	  systems will not fit into a single cache line anymore.
39600f0b825SBalbir Singh
39700f0b825SBalbir Singh	  Only enable when you're ok with these trade offs and really
39800f0b825SBalbir Singh	  sure you need the memory resource controller.
39900f0b825SBalbir Singh
400cf475ad2SBalbir Singh	  This config option also selects MM_OWNER config option, which
401cf475ad2SBalbir Singh	  could in turn add some fork/exit overhead.
402cf475ad2SBalbir Singh
40388a22c98SKay Sieversconfig SYSFS_DEPRECATED
404d47846c5SIngo Molnar	bool
405d47846c5SIngo Molnar
406d47846c5SIngo Molnarconfig SYSFS_DEPRECATED_V2
40788a22c98SKay Sievers	bool "Create deprecated sysfs files"
4089148fe87SRandy Dunlap	depends on SYSFS
40988a22c98SKay Sievers	default y
410d47846c5SIngo Molnar	select SYSFS_DEPRECATED
41188a22c98SKay Sievers	help
41288a22c98SKay Sievers	  This option creates deprecated symlinks such as the
41388a22c98SKay Sievers	  "device"-link, the <subsystem>:<name>-link, and the
41488a22c98SKay Sievers	  "bus"-link. It may also add deprecated key in the
41588a22c98SKay Sievers	  uevent environment.
41688a22c98SKay Sievers	  None of these features or values should be used today, as
41788a22c98SKay Sievers	  they export driver core implementation details to userspace
41888a22c98SKay Sievers	  or export properties which can't be kept stable across kernel
41988a22c98SKay Sievers	  releases.
42088a22c98SKay Sievers
42188a22c98SKay Sievers	  If enabled, this option will also move any device structures
4223dde6ad8SDavid Sterba	  that belong to a class, back into the /sys/class hierarchy, in
423024440d2SGreg Kroah-Hartman	  order to support older versions of udev and some userspace
424024440d2SGreg Kroah-Hartman	  programs.
42588a22c98SKay Sievers
426024440d2SGreg Kroah-Hartman	  If you are using a distro with the most recent userspace
427024440d2SGreg Kroah-Hartman	  packages, it should be safe to say N here.
42888a22c98SKay Sievers
4298793d854SPaul Menageconfig PROC_PID_CPUSET
4308793d854SPaul Menage	bool "Include legacy /proc/<pid>/cpuset file"
4318793d854SPaul Menage	depends on CPUSETS
4328793d854SPaul Menage	default y
4338793d854SPaul Menage
434b86ff981SJens Axboeconfig RELAY
435b86ff981SJens Axboe	bool "Kernel->user space relay support (formerly relayfs)"
436b86ff981SJens Axboe	help
437b86ff981SJens Axboe	  This option enables support for relay interface support in
438b86ff981SJens Axboe	  certain file systems (such as debugfs).
439b86ff981SJens Axboe	  It is designed to provide an efficient mechanism for tools and
440b86ff981SJens Axboe	  facilities to relay large amounts of data from kernel space to
441b86ff981SJens Axboe	  user space.
442b86ff981SJens Axboe
443b86ff981SJens Axboe	  If unsure, say N.
444b86ff981SJens Axboe
445c5289a69SPavel Emelyanovconfig NAMESPACES
446c5289a69SPavel Emelyanov	bool "Namespaces support" if EMBEDDED
447c5289a69SPavel Emelyanov	default !EMBEDDED
448c5289a69SPavel Emelyanov	help
449c5289a69SPavel Emelyanov	  Provides the way to make tasks work with different objects using
450c5289a69SPavel Emelyanov	  the same id. For example same IPC id may refer to different objects
451c5289a69SPavel Emelyanov	  or same user id or pid may refer to different tasks when used in
452c5289a69SPavel Emelyanov	  different namespaces.
453c5289a69SPavel Emelyanov
45458bfdd6dSPavel Emelyanovconfig UTS_NS
45558bfdd6dSPavel Emelyanov	bool "UTS namespace"
45658bfdd6dSPavel Emelyanov	depends on NAMESPACES
45758bfdd6dSPavel Emelyanov	help
45858bfdd6dSPavel Emelyanov	  In this namespace tasks see different info provided with the
45958bfdd6dSPavel Emelyanov	  uname() system call
46058bfdd6dSPavel Emelyanov
461ae5e1b22SPavel Emelyanovconfig IPC_NS
462ae5e1b22SPavel Emelyanov	bool "IPC namespace"
463ae5e1b22SPavel Emelyanov	depends on NAMESPACES && SYSVIPC
464ae5e1b22SPavel Emelyanov	help
465ae5e1b22SPavel Emelyanov	  In this namespace tasks work with IPC ids which correspond to
466ae5e1b22SPavel Emelyanov	  different IPC objects in different namespaces
467ae5e1b22SPavel Emelyanov
468aee16ce7SPavel Emelyanovconfig USER_NS
469aee16ce7SPavel Emelyanov	bool "User namespace (EXPERIMENTAL)"
470aee16ce7SPavel Emelyanov	depends on NAMESPACES && EXPERIMENTAL
471aee16ce7SPavel Emelyanov	help
472aee16ce7SPavel Emelyanov	  This allows containers, i.e. vservers, to use user namespaces
473aee16ce7SPavel Emelyanov	  to provide different user info for different servers.
474aee16ce7SPavel Emelyanov	  If unsure, say N.
475aee16ce7SPavel Emelyanov
47674bd59bbSPavel Emelyanovconfig PID_NS
47774bd59bbSPavel Emelyanov	bool "PID Namespaces (EXPERIMENTAL)"
47874bd59bbSPavel Emelyanov	default n
47974bd59bbSPavel Emelyanov	depends on NAMESPACES && EXPERIMENTAL
48074bd59bbSPavel Emelyanov	help
48174bd59bbSPavel Emelyanov	  Suport process id namespaces.  This allows having multiple
48274bd59bbSPavel Emelyanov	  process with the same pid as long as they are in different
48374bd59bbSPavel Emelyanov	  pid namespaces.  This is a building block of containers.
48474bd59bbSPavel Emelyanov
48574bd59bbSPavel Emelyanov	  Unless you want to work with an experimental feature
48674bd59bbSPavel Emelyanov	  say N here.
48774bd59bbSPavel Emelyanov
488f991633dSDimitri Gorokhovikconfig BLK_DEV_INITRD
489f991633dSDimitri Gorokhovik	bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
490f991633dSDimitri Gorokhovik	depends on BROKEN || !FRV
491f991633dSDimitri Gorokhovik	help
492f991633dSDimitri Gorokhovik	  The initial RAM filesystem is a ramfs which is loaded by the
493f991633dSDimitri Gorokhovik	  boot loader (loadlin or lilo) and that is mounted as root
494f991633dSDimitri Gorokhovik	  before the normal boot procedure. It is typically used to
495f991633dSDimitri Gorokhovik	  load modules needed to mount the "real" root file system,
496f991633dSDimitri Gorokhovik	  etc. See <file:Documentation/initrd.txt> for details.
497f991633dSDimitri Gorokhovik
498f991633dSDimitri Gorokhovik	  If RAM disk support (BLK_DEV_RAM) is also included, this
499f991633dSDimitri Gorokhovik	  also enables initial RAM disk (initrd) support and adds
500f991633dSDimitri Gorokhovik	  15 Kbytes (more on some other architectures) to the kernel size.
501f991633dSDimitri Gorokhovik
502f991633dSDimitri Gorokhovik	  If unsure say Y.
503f991633dSDimitri Gorokhovik
504c33df4eaSJean-Paul Samanif BLK_DEV_INITRD
505c33df4eaSJean-Paul Saman
506dbec4866SSam Ravnborgsource "usr/Kconfig"
507dbec4866SSam Ravnborg
508c33df4eaSJean-Paul Samanendif
509c33df4eaSJean-Paul Saman
510c45b4f1fSLinus Torvaldsconfig CC_OPTIMIZE_FOR_SIZE
51196fffeb4SIngo Molnar	bool "Optimize for size"
512c45b4f1fSLinus Torvalds	default y
513c45b4f1fSLinus Torvalds	help
514c45b4f1fSLinus Torvalds	  Enabling this option will pass "-Os" instead of "-O2" to gcc
515c45b4f1fSLinus Torvalds	  resulting in a smaller kernel.
516c45b4f1fSLinus Torvalds
517c45b4f1fSLinus Torvalds	  If unsure, say N.
518c45b4f1fSLinus Torvalds
5190847062aSRandy Dunlapconfig SYSCTL
5200847062aSRandy Dunlap	bool
5210847062aSRandy Dunlap
5221da177e4SLinus Torvaldsmenuconfig EMBEDDED
5231da177e4SLinus Torvalds	bool "Configure standard kernel features (for small systems)"
5241da177e4SLinus Torvalds	help
5251da177e4SLinus Torvalds	  This option allows certain base kernel options and settings
5261da177e4SLinus Torvalds          to be disabled or tweaked. This is for specialized
5271da177e4SLinus Torvalds          environments which can tolerate a "non-standard" kernel.
5281da177e4SLinus Torvalds          Only use this if you really know what you are doing.
5291da177e4SLinus Torvalds
530ae81f9e3SChuck Ebbertconfig UID16
531ae81f9e3SChuck Ebbert	bool "Enable 16-bit UID system calls" if EMBEDDED
53209337f50SDavid S. Miller	depends on ARM || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && COMPAT) || UML || (X86_64 && IA32_EMULATION)
533ae81f9e3SChuck Ebbert	default y
534ae81f9e3SChuck Ebbert	help
535ae81f9e3SChuck Ebbert	  This enables the legacy 16-bit UID syscall wrappers.
536ae81f9e3SChuck Ebbert
537b89a8171SEric W. Biedermanconfig SYSCTL_SYSCALL
5380847062aSRandy Dunlap	bool "Sysctl syscall support" if EMBEDDED
53913bb7e37SEric W. Biederman	default y
540b89a8171SEric W. Biederman	select SYSCTL
541b89a8171SEric W. Biederman	---help---
54213bb7e37SEric W. Biederman	  sys_sysctl uses binary paths that have been found challenging
54313bb7e37SEric W. Biederman	  to properly maintain and use.  The interface in /proc/sys
54413bb7e37SEric W. Biederman	  using paths with ascii names is now the primary path to this
54513bb7e37SEric W. Biederman	  information.
546b89a8171SEric W. Biederman
54713bb7e37SEric W. Biederman	  Almost nothing using the binary sysctl interface so if you are
54813bb7e37SEric W. Biederman	  trying to save some space it is probably safe to disable this,
54913bb7e37SEric W. Biederman	  making your kernel marginally smaller.
550b89a8171SEric W. Biederman
55113bb7e37SEric W. Biederman	  If unsure say Y here.
552ae81f9e3SChuck Ebbert
553*88f458e4SHolger Schurigconfig SYSCTL_SYSCALL_CHECK
554*88f458e4SHolger Schurig	bool "Sysctl checks" if EMBEDDED
555*88f458e4SHolger Schurig	depends on SYSCTL_SYSCALL
556*88f458e4SHolger Schurig	default y
557*88f458e4SHolger Schurig	---help---
558*88f458e4SHolger Schurig	  sys_sysctl uses binary paths that have been found challenging
559*88f458e4SHolger Schurig	  to properly maintain and use. This enables checks that help
560*88f458e4SHolger Schurig	  you to keep things correct.
561*88f458e4SHolger Schurig
562*88f458e4SHolger Schurig	  If unsure say Y here.
563*88f458e4SHolger Schurig
5641da177e4SLinus Torvaldsconfig KALLSYMS
565979c6a1eSJesper Juhl	 bool "Load all symbols for debugging/ksymoops" if EMBEDDED
5661da177e4SLinus Torvalds	 default y
5671da177e4SLinus Torvalds	 help
5681da177e4SLinus Torvalds	   Say Y here to let the kernel print out symbolic crash information and
5691da177e4SLinus Torvalds	   symbolic stack backtraces. This increases the size of the kernel
5701da177e4SLinus Torvalds	   somewhat, as all symbols have to be loaded into the kernel image.
5711da177e4SLinus Torvalds
5721da177e4SLinus Torvaldsconfig KALLSYMS_ALL
5731da177e4SLinus Torvalds	bool "Include all symbols in kallsyms"
5741da177e4SLinus Torvalds	depends on DEBUG_KERNEL && KALLSYMS
5751da177e4SLinus Torvalds	help
5761da177e4SLinus Torvalds	   Normally kallsyms only contains the symbols of functions, for nicer
5771da177e4SLinus Torvalds	   OOPS messages.  Some debuggers can use kallsyms for other
578f9f97bc0SJesper Juhl	   symbols too: say Y here to include all symbols, if you need them
579f9f97bc0SJesper Juhl	   and you don't care about adding 300k to the size of your kernel.
5801da177e4SLinus Torvalds
5811da177e4SLinus Torvalds	   Say N.
5821da177e4SLinus Torvalds
5831da177e4SLinus Torvaldsconfig KALLSYMS_EXTRA_PASS
5841da177e4SLinus Torvalds	bool "Do an extra kallsyms pass"
5851da177e4SLinus Torvalds	depends on KALLSYMS
5861da177e4SLinus Torvalds	help
5871da177e4SLinus Torvalds	   If kallsyms is not working correctly, the build will fail with
5881da177e4SLinus Torvalds	   inconsistent kallsyms data.  If that occurs, log a bug report and
5891da177e4SLinus Torvalds	   turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
5901da177e4SLinus Torvalds	   Always say N here unless you find a bug in kallsyms, which must be
5911da177e4SLinus Torvalds	   reported.  KALLSYMS_EXTRA_PASS is only a temporary workaround while
5921da177e4SLinus Torvalds	   you wait for kallsyms to be fixed.
5931da177e4SLinus Torvalds
594d59745ceSMatt Mackall
595712f47ceSGreg Kroah-Hartmanconfig HOTPLUG
596712f47ceSGreg Kroah-Hartman	bool "Support for hot-pluggable devices" if EMBEDDED
597712f47ceSGreg Kroah-Hartman	default y
598712f47ceSGreg Kroah-Hartman	help
599712f47ceSGreg Kroah-Hartman	  This option is provided for the case where no hotplug or uevent
600712f47ceSGreg Kroah-Hartman	  capabilities is wanted by the kernel.  You should only consider
601712f47ceSGreg Kroah-Hartman	  disabling this option for embedded systems that do not use modules, a
602712f47ceSGreg Kroah-Hartman	  dynamic /dev tree, or dynamic device discovery.  Just say Y.
603712f47ceSGreg Kroah-Hartman
604d59745ceSMatt Mackallconfig PRINTK
605d59745ceSMatt Mackall	default y
606d59745ceSMatt Mackall	bool "Enable support for printk" if EMBEDDED
607d59745ceSMatt Mackall	help
608d59745ceSMatt Mackall	  This option enables normal printk support. Removing it
609d59745ceSMatt Mackall	  eliminates most of the message strings from the kernel image
610d59745ceSMatt Mackall	  and makes the kernel more or less silent. As this makes it
611d59745ceSMatt Mackall	  very difficult to diagnose system problems, saying N here is
612d59745ceSMatt Mackall	  strongly discouraged.
613d59745ceSMatt Mackall
614c8538a7aSMatt Mackallconfig BUG
615c8538a7aSMatt Mackall	bool "BUG() support" if EMBEDDED
616c8538a7aSMatt Mackall	default y
617c8538a7aSMatt Mackall	help
618c8538a7aSMatt Mackall          Disabling this option eliminates support for BUG and WARN, reducing
619c8538a7aSMatt Mackall          the size of your kernel image and potentially quietly ignoring
620c8538a7aSMatt Mackall          numerous fatal conditions. You should only consider disabling this
621c8538a7aSMatt Mackall          option for embedded systems with no facilities for reporting errors.
622c8538a7aSMatt Mackall          Just say Y.
623c8538a7aSMatt Mackall
624708e9a79SMatt Mackallconfig ELF_CORE
625708e9a79SMatt Mackall	default y
626708e9a79SMatt Mackall	bool "Enable ELF core dumps" if EMBEDDED
627708e9a79SMatt Mackall	help
628708e9a79SMatt Mackall	  Enable support for generating core dumps. Disabling saves about 4k.
629708e9a79SMatt Mackall
63032a93233SIngo Molnarconfig COMPAT_BRK
63132a93233SIngo Molnar	bool "Disable heap randomization"
63232a93233SIngo Molnar	default y
63332a93233SIngo Molnar	help
63432a93233SIngo Molnar	  Randomizing heap placement makes heap exploits harder, but it
63532a93233SIngo Molnar	  also breaks ancient binaries (including anything libc5 based).
63632a93233SIngo Molnar	  This option changes the bootup default to heap randomization
63732a93233SIngo Molnar	  disabled, and can be overriden runtime by setting
63832a93233SIngo Molnar	  /proc/sys/kernel/randomize_va_space to 2.
63932a93233SIngo Molnar
640166124fdSIngo Molnar	  On non-ancient distros (post-2000 ones) N is usually a safe choice.
64132a93233SIngo Molnar
6421da177e4SLinus Torvaldsconfig BASE_FULL
6431da177e4SLinus Torvalds	default y
6441da177e4SLinus Torvalds	bool "Enable full-sized data structures for core" if EMBEDDED
6451da177e4SLinus Torvalds	help
6461da177e4SLinus Torvalds	  Disabling this option reduces the size of miscellaneous core
6471da177e4SLinus Torvalds	  kernel data structures. This saves memory on small machines,
6481da177e4SLinus Torvalds	  but may reduce performance.
6491da177e4SLinus Torvalds
6501da177e4SLinus Torvaldsconfig FUTEX
6511da177e4SLinus Torvalds	bool "Enable futex support" if EMBEDDED
6521da177e4SLinus Torvalds	default y
65323f78d4aSIngo Molnar	select RT_MUTEXES
6541da177e4SLinus Torvalds	help
6551da177e4SLinus Torvalds	  Disabling this option will cause the kernel to be built without
6561da177e4SLinus Torvalds	  support for "fast userspace mutexes".  The resulting kernel may not
6571da177e4SLinus Torvalds	  run glibc-based applications correctly.
6581da177e4SLinus Torvalds
6595dc8bf81SDavide Libenziconfig ANON_INODES
660448e3ceeSAdrian Bunk	bool
6615dc8bf81SDavide Libenzi
6621da177e4SLinus Torvaldsconfig EPOLL
6631da177e4SLinus Torvalds	bool "Enable eventpoll support" if EMBEDDED
6641da177e4SLinus Torvalds	default y
665448e3ceeSAdrian Bunk	select ANON_INODES
6661da177e4SLinus Torvalds	help
6671da177e4SLinus Torvalds	  Disabling this option will cause the kernel to be built without
6681da177e4SLinus Torvalds	  support for epoll family of system calls.
6691da177e4SLinus Torvalds
670fba2afaaSDavide Libenziconfig SIGNALFD
671fba2afaaSDavide Libenzi	bool "Enable signalfd() system call" if EMBEDDED
672448e3ceeSAdrian Bunk	select ANON_INODES
673fba2afaaSDavide Libenzi	default y
674fba2afaaSDavide Libenzi	help
675fba2afaaSDavide Libenzi	  Enable the signalfd() system call that allows to receive signals
676fba2afaaSDavide Libenzi	  on a file descriptor.
677fba2afaaSDavide Libenzi
678fba2afaaSDavide Libenzi	  If unsure, say Y.
679fba2afaaSDavide Libenzi
680b215e283SDavide Libenziconfig TIMERFD
681b215e283SDavide Libenzi	bool "Enable timerfd() system call" if EMBEDDED
682448e3ceeSAdrian Bunk	select ANON_INODES
683b215e283SDavide Libenzi	default y
684b215e283SDavide Libenzi	help
685b215e283SDavide Libenzi	  Enable the timerfd() system call that allows to receive timer
686b215e283SDavide Libenzi	  events on a file descriptor.
687b215e283SDavide Libenzi
688b215e283SDavide Libenzi	  If unsure, say Y.
689b215e283SDavide Libenzi
690e1ad7468SDavide Libenziconfig EVENTFD
691e1ad7468SDavide Libenzi	bool "Enable eventfd() system call" if EMBEDDED
692448e3ceeSAdrian Bunk	select ANON_INODES
693e1ad7468SDavide Libenzi	default y
694e1ad7468SDavide Libenzi	help
695e1ad7468SDavide Libenzi	  Enable the eventfd() system call that allows to receive both
696e1ad7468SDavide Libenzi	  kernel notification (ie. KAIO) or userspace notifications.
697e1ad7468SDavide Libenzi
698e1ad7468SDavide Libenzi	  If unsure, say Y.
699e1ad7468SDavide Libenzi
7001da177e4SLinus Torvaldsconfig SHMEM
7011da177e4SLinus Torvalds	bool "Use full shmem filesystem" if EMBEDDED
7021da177e4SLinus Torvalds	default y
7031da177e4SLinus Torvalds	depends on MMU
7041da177e4SLinus Torvalds	help
7051da177e4SLinus Torvalds	  The shmem is an internal filesystem used to manage shared memory.
7061da177e4SLinus Torvalds	  It is backed by swap and manages resource limits. It is also exported
7071da177e4SLinus Torvalds	  to userspace as tmpfs if TMPFS is enabled. Disabling this
7081da177e4SLinus Torvalds	  option replaces shmem and tmpfs with the much simpler ramfs code,
7091da177e4SLinus Torvalds	  which may be appropriate on small systems without swap.
7101da177e4SLinus Torvalds
711f8891e5eSChristoph Lameterconfig VM_EVENT_COUNTERS
712f8891e5eSChristoph Lameter	default y
713f8891e5eSChristoph Lameter	bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
714f8891e5eSChristoph Lameter	help
7152aea4fb6SPaul Jackson	  VM event counters are needed for event counts to be shown.
7162aea4fb6SPaul Jackson	  This option allows the disabling of the VM event counters
7172aea4fb6SPaul Jackson	  on EMBEDDED systems.  /proc/vmstat will only show page counts
7182aea4fb6SPaul Jackson	  if VM event counters are disabled.
719f8891e5eSChristoph Lameter
72041ecc55bSChristoph Lameterconfig SLUB_DEBUG
72141ecc55bSChristoph Lameter	default y
72241ecc55bSChristoph Lameter	bool "Enable SLUB debugging support" if EMBEDDED
723d4751a27SChristoph Lameter	depends on SLUB
72441ecc55bSChristoph Lameter	help
72541ecc55bSChristoph Lameter	  SLUB has extensive debug support features. Disabling these can
72641ecc55bSChristoph Lameter	  result in significant savings in code size. This also disables
72741ecc55bSChristoph Lameter	  SLUB sysfs support. /sys/slab will not exist and there will be
72841ecc55bSChristoph Lameter	  no support for cache validation etc.
72941ecc55bSChristoph Lameter
73081819f0fSChristoph Lameterchoice
73181819f0fSChristoph Lameter	prompt "Choose SLAB allocator"
732a0acd820SChristoph Lameter	default SLUB
73381819f0fSChristoph Lameter	help
73481819f0fSChristoph Lameter	   This option allows to select a slab allocator.
73581819f0fSChristoph Lameter
73681819f0fSChristoph Lameterconfig SLAB
73781819f0fSChristoph Lameter	bool "SLAB"
73881819f0fSChristoph Lameter	help
73981819f0fSChristoph Lameter	  The regular slab allocator that is established and known to work
74034013886SChristoph Lameter	  well in all environments. It organizes cache hot objects in
74181819f0fSChristoph Lameter	  per cpu and per node queues. SLAB is the default choice for
74234013886SChristoph Lameter	  a slab allocator.
74381819f0fSChristoph Lameter
74481819f0fSChristoph Lameterconfig SLUB
74581819f0fSChristoph Lameter	bool "SLUB (Unqueued Allocator)"
74681819f0fSChristoph Lameter	help
74781819f0fSChristoph Lameter	   SLUB is a slab allocator that minimizes cache line usage
74881819f0fSChristoph Lameter	   instead of managing queues of cached objects (SLAB approach).
74981819f0fSChristoph Lameter	   Per cpu caching is realized using slabs of objects instead
75081819f0fSChristoph Lameter	   of queues of objects. SLUB can use memory efficiently
75134013886SChristoph Lameter	   and has enhanced diagnostics.
75281819f0fSChristoph Lameter
75381819f0fSChristoph Lameterconfig SLOB
75484a01c2fSPaul Mundt	depends on EMBEDDED
75581819f0fSChristoph Lameter	bool "SLOB (Simple Allocator)"
75681819f0fSChristoph Lameter	help
75737291458SMatt Mackall	   SLOB replaces the stock allocator with a drastically simpler
75837291458SMatt Mackall	   allocator. SLOB is generally more space efficient but
75937291458SMatt Mackall	   does not perform as well on large systems.
76081819f0fSChristoph Lameter
76181819f0fSChristoph Lameterendchoice
76281819f0fSChristoph Lameter
763125e5645SMathieu Desnoyersconfig PROFILING
764125e5645SMathieu Desnoyers	bool "Profiling support (EXPERIMENTAL)"
765125e5645SMathieu Desnoyers	help
766125e5645SMathieu Desnoyers	  Say Y here to enable the extended profiling support mechanisms used
767125e5645SMathieu Desnoyers	  by profilers such as OProfile.
768125e5645SMathieu Desnoyers
769125e5645SMathieu Desnoyersconfig MARKERS
770125e5645SMathieu Desnoyers	bool "Activate markers"
771125e5645SMathieu Desnoyers	help
772125e5645SMathieu Desnoyers	  Place an empty function call at each marker site. Can be
773125e5645SMathieu Desnoyers	  dynamically changed for a probe function.
774125e5645SMathieu Desnoyers
775fb32e03fSMathieu Desnoyerssource "arch/Kconfig"
776fb32e03fSMathieu Desnoyers
7771e883281SMatt Mackallconfig PROC_PAGE_MONITOR
7781e883281SMatt Mackall 	default y
7791e883281SMatt Mackall	depends on PROC_FS && MMU
7801e883281SMatt Mackall	bool "Enable /proc page monitoring" if EMBEDDED
7811e883281SMatt Mackall 	help
7821e883281SMatt Mackall	  Various /proc files exist to monitor process memory utilization:
7831e883281SMatt Mackall	  /proc/pid/smaps, /proc/pid/clear_refs, /proc/pid/pagemap,
7841e883281SMatt Mackall	  /proc/kpagecount, and /proc/kpageflags. Disabling these
7851e883281SMatt Mackall          interfaces will reduce the size of the kernel by approximately 4kb.
7861e883281SMatt Mackall
7871da177e4SLinus Torvaldsendmenu		# General setup
7881da177e4SLinus Torvalds
789158a9624SLinus Torvaldsconfig SLABINFO
790158a9624SLinus Torvalds	bool
791158a9624SLinus Torvalds	depends on PROC_FS
7920f389ec6SChristoph Lameter	depends on SLAB || SLUB_DEBUG
793158a9624SLinus Torvalds	default y
794158a9624SLinus Torvalds
795ae81f9e3SChuck Ebbertconfig RT_MUTEXES
796ae81f9e3SChuck Ebbert	boolean
797ae81f9e3SChuck Ebbert	select PLIST
798ae81f9e3SChuck Ebbert
7991da177e4SLinus Torvaldsconfig TINY_SHMEM
8001da177e4SLinus Torvalds	default !SHMEM
8011da177e4SLinus Torvalds	bool
8021da177e4SLinus Torvalds
8031da177e4SLinus Torvaldsconfig BASE_SMALL
8041da177e4SLinus Torvalds	int
8051da177e4SLinus Torvalds	default 0 if BASE_FULL
8061da177e4SLinus Torvalds	default 1 if !BASE_FULL
8071da177e4SLinus Torvalds
80866da5733SJan Engelhardtmenuconfig MODULES
8091da177e4SLinus Torvalds	bool "Enable loadable module support"
8101da177e4SLinus Torvalds	help
8111da177e4SLinus Torvalds	  Kernel modules are small pieces of compiled code which can
8121da177e4SLinus Torvalds	  be inserted in the running kernel, rather than being
8131da177e4SLinus Torvalds	  permanently built into the kernel.  You use the "modprobe"
8141da177e4SLinus Torvalds	  tool to add (and sometimes remove) them.  If you say Y here,
8151da177e4SLinus Torvalds	  many parts of the kernel can be built as modules (by
8161da177e4SLinus Torvalds	  answering M instead of Y where indicated): this is most
8171da177e4SLinus Torvalds	  useful for infrequently used options which are not required
8181da177e4SLinus Torvalds	  for booting.  For more information, see the man pages for
8191da177e4SLinus Torvalds	  modprobe, lsmod, modinfo, insmod and rmmod.
8201da177e4SLinus Torvalds
8211da177e4SLinus Torvalds	  If you say Y here, you will need to run "make
8221da177e4SLinus Torvalds	  modules_install" to put the modules under /lib/modules/
8231da177e4SLinus Torvalds	  where modprobe can find them (you may need to be root to do
8241da177e4SLinus Torvalds	  this).
8251da177e4SLinus Torvalds
8261da177e4SLinus Torvalds	  If unsure, say Y.
8271da177e4SLinus Torvalds
8281da177e4SLinus Torvaldsconfig MODULE_UNLOAD
8291da177e4SLinus Torvalds	bool "Module unloading"
8301da177e4SLinus Torvalds	depends on MODULES
8311da177e4SLinus Torvalds	help
8321da177e4SLinus Torvalds	  Without this option you will not be able to unload any
8331da177e4SLinus Torvalds	  modules (note that some modules may not be unloadable
8341da177e4SLinus Torvalds	  anyway), which makes your kernel slightly smaller and
8351da177e4SLinus Torvalds	  simpler.  If unsure, say Y.
8361da177e4SLinus Torvalds
8371da177e4SLinus Torvaldsconfig MODULE_FORCE_UNLOAD
8381da177e4SLinus Torvalds	bool "Forced module unloading"
8391da177e4SLinus Torvalds	depends on MODULE_UNLOAD && EXPERIMENTAL
8401da177e4SLinus Torvalds	help
8411da177e4SLinus Torvalds	  This option allows you to force a module to unload, even if the
8421da177e4SLinus Torvalds	  kernel believes it is unsafe: the kernel will remove the module
8431da177e4SLinus Torvalds	  without waiting for anyone to stop using it (using the -f option to
8441da177e4SLinus Torvalds	  rmmod).  This is mainly for kernel developers and desperate users.
8451da177e4SLinus Torvalds	  If unsure, say N.
8461da177e4SLinus Torvalds
8471da177e4SLinus Torvaldsconfig MODVERSIONS
8480d541643SSam Ravnborg	bool "Module versioning support"
8490d541643SSam Ravnborg	depends on MODULES
8501da177e4SLinus Torvalds	help
8511da177e4SLinus Torvalds	  Usually, you have to use modules compiled with your kernel.
8521da177e4SLinus Torvalds	  Saying Y here makes it sometimes possible to use modules
8531da177e4SLinus Torvalds	  compiled for different kernels, by adding enough information
8541da177e4SLinus Torvalds	  to the modules to (hopefully) spot any changes which would
8551da177e4SLinus Torvalds	  make them incompatible with the kernel you are running.  If
8561da177e4SLinus Torvalds	  unsure, say N.
8571da177e4SLinus Torvalds
8581da177e4SLinus Torvaldsconfig MODULE_SRCVERSION_ALL
8591da177e4SLinus Torvalds	bool "Source checksum for all modules"
8601da177e4SLinus Torvalds	depends on MODULES
8611da177e4SLinus Torvalds	help
8621da177e4SLinus Torvalds	  Modules which contain a MODULE_VERSION get an extra "srcversion"
8631da177e4SLinus Torvalds	  field inserted into their modinfo section, which contains a
8641da177e4SLinus Torvalds    	  sum of the source files which made it.  This helps maintainers
8651da177e4SLinus Torvalds	  see exactly which source was used to build a module (since
8661da177e4SLinus Torvalds	  others sometimes change the module source without updating
8671da177e4SLinus Torvalds	  the version).  With this option, such a "srcversion" field
8681da177e4SLinus Torvalds	  will be created for all modules.  If unsure, say N.
8691da177e4SLinus Torvalds
8701da177e4SLinus Torvaldsconfig KMOD
8711da177e4SLinus Torvalds	bool "Automatic kernel module loading"
8721da177e4SLinus Torvalds	depends on MODULES
8731da177e4SLinus Torvalds	help
8741da177e4SLinus Torvalds	  Normally when you have selected some parts of the kernel to
8751da177e4SLinus Torvalds	  be created as kernel modules, you must load them (using the
8761da177e4SLinus Torvalds	  "modprobe" command) before you can use them. If you say Y
8771da177e4SLinus Torvalds	  here, some parts of the kernel will be able to load modules
8781da177e4SLinus Torvalds	  automatically: when a part of the kernel needs a module, it
8791da177e4SLinus Torvalds	  runs modprobe with the appropriate arguments, thereby
8801da177e4SLinus Torvalds	  loading the module if it is available.  If unsure, say Y.
8811da177e4SLinus Torvalds
8821da177e4SLinus Torvaldsconfig STOP_MACHINE
8831da177e4SLinus Torvalds	bool
8841da177e4SLinus Torvalds	default y
8851da177e4SLinus Torvalds	depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
8861da177e4SLinus Torvalds	help
8871da177e4SLinus Torvalds	  Need stop_machine() primitive.
8883a65dfe8SJens Axboe
8893a65dfe8SJens Axboesource "block/Kconfig"
890e98c3202SAvi Kivity
891e98c3202SAvi Kivityconfig PREEMPT_NOTIFIERS
892e98c3202SAvi Kivity	bool
893e260be67SPaul E. McKenney
894e260be67SPaul E. McKenneyconfig CLASSIC_RCU
89521bbb39cSPaul E. McKenney	def_bool !PREEMPT_RCU
896e260be67SPaul E. McKenney	help
897e260be67SPaul E. McKenney	  This option selects the classic RCU implementation that is
898e260be67SPaul E. McKenney	  designed for best read-side performance on non-realtime
89921bbb39cSPaul E. McKenney	  systems.  Classic RCU is the default.  Note that the
90021bbb39cSPaul E. McKenney	  PREEMPT_RCU symbol is used to select/deselect this option.
901