xref: /openbmc/linux/init/Kconfig (revision 8b438766)
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"
1673531905SSam Ravnborg	default "$ARCH_DEFCONFIG"
17face4374SRoman Zippel	default "arch/$ARCH/defconfig"
18face4374SRoman Zippel
19b99b87f7SPeter Oberparleiterconfig CONSTRUCTORS
20b99b87f7SPeter Oberparleiter	bool
21b99b87f7SPeter Oberparleiter	depends on !UML
22b99b87f7SPeter Oberparleiter
23e360adbeSPeter Zijlstraconfig IRQ_WORK
24e360adbeSPeter Zijlstra	bool
25e360adbeSPeter Zijlstra
261dbdc6f1SDavid Daneyconfig BUILDTIME_EXTABLE_SORT
271dbdc6f1SDavid Daney	bool
281dbdc6f1SDavid Daney
29ff0cfc66SAl Boldimenu "General setup"
301da177e4SLinus Torvalds
311da177e4SLinus Torvaldsconfig EXPERIMENTAL
325a958db3SKees Cook	bool
335a958db3SKees Cook	default y
341da177e4SLinus Torvalds
351da177e4SLinus Torvaldsconfig BROKEN
361da177e4SLinus Torvalds	bool
371da177e4SLinus Torvalds
381da177e4SLinus Torvaldsconfig BROKEN_ON_SMP
391da177e4SLinus Torvalds	bool
401da177e4SLinus Torvalds	depends on BROKEN || !SMP
411da177e4SLinus Torvalds	default y
421da177e4SLinus Torvalds
431da177e4SLinus Torvaldsconfig INIT_ENV_ARG_LIMIT
441da177e4SLinus Torvalds	int
45dd673bcaSAdrian Bunk	default 32 if !UML
46dd673bcaSAdrian Bunk	default 128 if UML
471da177e4SLinus Torvalds	help
4834ad92c2SRandy Dunlap	  Maximum of each of the number of arguments and environment
4934ad92c2SRandy Dunlap	  variables passed to init from the kernel command line.
501da177e4SLinus Torvalds
511da177e4SLinus Torvalds
5284336466SRoland McGrathconfig CROSS_COMPILE
5384336466SRoland McGrath	string "Cross-compiler tool prefix"
5484336466SRoland McGrath	help
5584336466SRoland McGrath	  Same as running 'make CROSS_COMPILE=prefix-' but stored for
5684336466SRoland McGrath	  default make runs in this kernel build directory.  You don't
5784336466SRoland McGrath	  need to set this unless you want the configured kernel build
5884336466SRoland McGrath	  directory to select the cross-compiler automatically.
5984336466SRoland McGrath
601da177e4SLinus Torvaldsconfig LOCALVERSION
611da177e4SLinus Torvalds	string "Local version - append to kernel release"
621da177e4SLinus Torvalds	help
631da177e4SLinus Torvalds	  Append an extra string to the end of your kernel version.
641da177e4SLinus Torvalds	  This will show up when you type uname, for example.
651da177e4SLinus Torvalds	  The string you set here will be appended after the contents of
661da177e4SLinus Torvalds	  any files with a filename matching localversion* in your
671da177e4SLinus Torvalds	  object and source tree, in that order.  Your total string can
681da177e4SLinus Torvalds	  be a maximum of 64 characters.
691da177e4SLinus Torvalds
70aaebf433SRyan Andersonconfig LOCALVERSION_AUTO
71aaebf433SRyan Anderson	bool "Automatically append version information to the version string"
72aaebf433SRyan Anderson	default y
73aaebf433SRyan Anderson	help
74aaebf433SRyan Anderson	  This will try to automatically determine if the current tree is a
756e5a5420SRobert P. J. Day	  release tree by looking for git tags that belong to the current
766e5a5420SRobert P. J. Day	  top of tree revision.
77aaebf433SRyan Anderson
78aaebf433SRyan Anderson	  A string of the format -gxxxxxxxx will be added to the localversion
796e5a5420SRobert P. J. Day	  if a git-based tree is found.  The string generated by this will be
80aaebf433SRyan Anderson	  appended after any matching localversion* files, and after the value
816e5a5420SRobert P. J. Day	  set in CONFIG_LOCALVERSION.
82aaebf433SRyan Anderson
836e5a5420SRobert P. J. Day	  (The actual string used here is the first eight characters produced
846e5a5420SRobert P. J. Day	  by running the command:
856e5a5420SRobert P. J. Day
866e5a5420SRobert P. J. Day	    $ git rev-parse --verify HEAD
876e5a5420SRobert P. J. Day
886e5a5420SRobert P. J. Day	  which is done within the script "scripts/setlocalversion".)
89aaebf433SRyan Anderson
902e9f3bddSH. Peter Anvinconfig HAVE_KERNEL_GZIP
912e9f3bddSH. Peter Anvin	bool
922e9f3bddSH. Peter Anvin
932e9f3bddSH. Peter Anvinconfig HAVE_KERNEL_BZIP2
942e9f3bddSH. Peter Anvin	bool
952e9f3bddSH. Peter Anvin
962e9f3bddSH. Peter Anvinconfig HAVE_KERNEL_LZMA
972e9f3bddSH. Peter Anvin	bool
982e9f3bddSH. Peter Anvin
993ebe1243SLasse Collinconfig HAVE_KERNEL_XZ
1003ebe1243SLasse Collin	bool
1013ebe1243SLasse Collin
1027dd65febSAlbin Tonnerreconfig HAVE_KERNEL_LZO
1037dd65febSAlbin Tonnerre	bool
1047dd65febSAlbin Tonnerre
10530d65dbfSAlain Knaffchoice
10630d65dbfSAlain Knaff	prompt "Kernel compression mode"
10730d65dbfSAlain Knaff	default KERNEL_GZIP
1083ebe1243SLasse Collin	depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO
10930d65dbfSAlain Knaff	help
11030d65dbfSAlain Knaff	  The linux kernel is a kind of self-extracting executable.
11130d65dbfSAlain Knaff	  Several compression algorithms are available, which differ
11230d65dbfSAlain Knaff	  in efficiency, compression and decompression speed.
11330d65dbfSAlain Knaff	  Compression speed is only relevant when building a kernel.
11430d65dbfSAlain Knaff	  Decompression speed is relevant at each boot.
11530d65dbfSAlain Knaff
11630d65dbfSAlain Knaff	  If you have any problems with bzip2 or lzma compressed
11730d65dbfSAlain Knaff	  kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
11830d65dbfSAlain Knaff	  version of this functionality (bzip2 only), for 2.4, was
11930d65dbfSAlain Knaff	  supplied by Christian Ludwig)
12030d65dbfSAlain Knaff
12130d65dbfSAlain Knaff	  High compression options are mostly useful for users, who
12230d65dbfSAlain Knaff	  are low on disk space (embedded systems), but for whom ram
12330d65dbfSAlain Knaff	  size matters less.
12430d65dbfSAlain Knaff
12530d65dbfSAlain Knaff	  If in doubt, select 'gzip'
12630d65dbfSAlain Knaff
12730d65dbfSAlain Knaffconfig KERNEL_GZIP
12830d65dbfSAlain Knaff	bool "Gzip"
1292e9f3bddSH. Peter Anvin	depends on HAVE_KERNEL_GZIP
13030d65dbfSAlain Knaff	help
1317dd65febSAlbin Tonnerre	  The old and tried gzip compression. It provides a good balance
1327dd65febSAlbin Tonnerre	  between compression ratio and decompression speed.
13330d65dbfSAlain Knaff
13430d65dbfSAlain Knaffconfig KERNEL_BZIP2
13530d65dbfSAlain Knaff	bool "Bzip2"
1362e9f3bddSH. Peter Anvin	depends on HAVE_KERNEL_BZIP2
13730d65dbfSAlain Knaff	help
13830d65dbfSAlain Knaff	  Its compression ratio and speed is intermediate.
1390a4dd35cSRandy Dunlap	  Decompression speed is slowest among the choices.  The kernel
1402e9f3bddSH. Peter Anvin	  size is about 10% smaller with bzip2, in comparison to gzip.
1412e9f3bddSH. Peter Anvin	  Bzip2 uses a large amount of memory. For modern kernels you
1422e9f3bddSH. Peter Anvin	  will need at least 8MB RAM or more for booting.
14330d65dbfSAlain Knaff
14430d65dbfSAlain Knaffconfig KERNEL_LZMA
14530d65dbfSAlain Knaff	bool "LZMA"
1462e9f3bddSH. Peter Anvin	depends on HAVE_KERNEL_LZMA
14730d65dbfSAlain Knaff	help
1480a4dd35cSRandy Dunlap	  This compression algorithm's ratio is best.  Decompression speed
1490a4dd35cSRandy Dunlap	  is between gzip and bzip2.  Compression is slowest.
1500a4dd35cSRandy Dunlap	  The kernel size is about 33% smaller with LZMA in comparison to gzip.
15130d65dbfSAlain Knaff
1523ebe1243SLasse Collinconfig KERNEL_XZ
1533ebe1243SLasse Collin	bool "XZ"
1543ebe1243SLasse Collin	depends on HAVE_KERNEL_XZ
1553ebe1243SLasse Collin	help
1563ebe1243SLasse Collin	  XZ uses the LZMA2 algorithm and instruction set specific
1573ebe1243SLasse Collin	  BCJ filters which can improve compression ratio of executable
1583ebe1243SLasse Collin	  code. The size of the kernel is about 30% smaller with XZ in
1593ebe1243SLasse Collin	  comparison to gzip. On architectures for which there is a BCJ
1603ebe1243SLasse Collin	  filter (i386, x86_64, ARM, IA-64, PowerPC, and SPARC), XZ
1613ebe1243SLasse Collin	  will create a few percent smaller kernel than plain LZMA.
1623ebe1243SLasse Collin
1633ebe1243SLasse Collin	  The speed is about the same as with LZMA: The decompression
1643ebe1243SLasse Collin	  speed of XZ is better than that of bzip2 but worse than gzip
1653ebe1243SLasse Collin	  and LZO. Compression is slow.
1663ebe1243SLasse Collin
1677dd65febSAlbin Tonnerreconfig KERNEL_LZO
1687dd65febSAlbin Tonnerre	bool "LZO"
1697dd65febSAlbin Tonnerre	depends on HAVE_KERNEL_LZO
1707dd65febSAlbin Tonnerre	help
1710a4dd35cSRandy Dunlap	  Its compression ratio is the poorest among the choices. The kernel
172681b3049SStephan Sperber	  size is about 10% bigger than gzip; however its speed
1737dd65febSAlbin Tonnerre	  (both compression and decompression) is the fastest.
1747dd65febSAlbin Tonnerre
17530d65dbfSAlain Knaffendchoice
17630d65dbfSAlain Knaff
177bd5dc17bSJosh Triplettconfig DEFAULT_HOSTNAME
178bd5dc17bSJosh Triplett	string "Default hostname"
179bd5dc17bSJosh Triplett	default "(none)"
180bd5dc17bSJosh Triplett	help
181bd5dc17bSJosh Triplett	  This option determines the default system hostname before userspace
182bd5dc17bSJosh Triplett	  calls sethostname(2). The kernel traditionally uses "(none)" here,
183bd5dc17bSJosh Triplett	  but you may wish to use a different default here to make a minimal
184bd5dc17bSJosh Triplett	  system more usable with less configuration.
185bd5dc17bSJosh Triplett
1861da177e4SLinus Torvaldsconfig SWAP
1871da177e4SLinus Torvalds	bool "Support for paging of anonymous memory (swap)"
1889361401eSDavid Howells	depends on MMU && BLOCK
1891da177e4SLinus Torvalds	default y
1901da177e4SLinus Torvalds	help
1911da177e4SLinus Torvalds	  This option allows you to choose whether you want to have support
1921da177e4SLinus Torvalds	  for so called swap devices or swap files in your kernel that are
1931da177e4SLinus Torvalds	  used to provide more virtual memory than the actual RAM present
1941da177e4SLinus Torvalds	  in your computer.  If unsure say Y.
1951da177e4SLinus Torvalds
1961da177e4SLinus Torvaldsconfig SYSVIPC
1971da177e4SLinus Torvalds	bool "System V IPC"
1981da177e4SLinus Torvalds	---help---
1991da177e4SLinus Torvalds	  Inter Process Communication is a suite of library functions and
2001da177e4SLinus Torvalds	  system calls which let processes (running programs) synchronize and
2011da177e4SLinus Torvalds	  exchange information. It is generally considered to be a good thing,
2021da177e4SLinus Torvalds	  and some programs won't run unless you say Y here. In particular, if
2031da177e4SLinus Torvalds	  you want to run the DOS emulator dosemu under Linux (read the
2041da177e4SLinus Torvalds	  DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
2051da177e4SLinus Torvalds	  you'll need to say Y here.
2061da177e4SLinus Torvalds
2071da177e4SLinus Torvalds	  You can find documentation about IPC with "info ipc" and also in
2081da177e4SLinus Torvalds	  section 6.4 of the Linux Programmer's Guide, available from
2091da177e4SLinus Torvalds	  <http://www.tldp.org/guides.html>.
2101da177e4SLinus Torvalds
211a5494dcdSEric W. Biedermanconfig SYSVIPC_SYSCTL
212a5494dcdSEric W. Biederman	bool
213a5494dcdSEric W. Biederman	depends on SYSVIPC
214a5494dcdSEric W. Biederman	depends on SYSCTL
215a5494dcdSEric W. Biederman	default y
216a5494dcdSEric W. Biederman
2171da177e4SLinus Torvaldsconfig POSIX_MQUEUE
2181da177e4SLinus Torvalds	bool "POSIX Message Queues"
21919c92399SKees Cook	depends on NET
2201da177e4SLinus Torvalds	---help---
2211da177e4SLinus Torvalds	  POSIX variant of message queues is a part of IPC. In POSIX message
2221da177e4SLinus Torvalds	  queues every message has a priority which decides about succession
2231da177e4SLinus Torvalds	  of receiving it by a process. If you want to compile and run
2241da177e4SLinus Torvalds	  programs written e.g. for Solaris with use of its POSIX message
225b0e37650SRobert P. J. Day	  queues (functions mq_*) say Y here.
2261da177e4SLinus Torvalds
2271da177e4SLinus Torvalds	  POSIX message queues are visible as a filesystem called 'mqueue'
2281da177e4SLinus Torvalds	  and can be mounted somewhere if you want to do filesystem
2291da177e4SLinus Torvalds	  operations on message queues.
2301da177e4SLinus Torvalds
2311da177e4SLinus Torvalds	  If unsure, say Y.
2321da177e4SLinus Torvalds
233bdc8e5f8SSerge E. Hallynconfig POSIX_MQUEUE_SYSCTL
234bdc8e5f8SSerge E. Hallyn	bool
235bdc8e5f8SSerge E. Hallyn	depends on POSIX_MQUEUE
236bdc8e5f8SSerge E. Hallyn	depends on SYSCTL
237bdc8e5f8SSerge E. Hallyn	default y
238bdc8e5f8SSerge E. Hallyn
239990d6c2dSAneesh Kumar K.Vconfig FHANDLE
240990d6c2dSAneesh Kumar K.V	bool "open by fhandle syscalls"
241990d6c2dSAneesh Kumar K.V	select EXPORTFS
242990d6c2dSAneesh Kumar K.V	help
243990d6c2dSAneesh Kumar K.V	  If you say Y here, a user level program will be able to map
244990d6c2dSAneesh Kumar K.V	  file names to handle and then later use the handle for
245990d6c2dSAneesh Kumar K.V	  different file system operations. This is useful in implementing
246990d6c2dSAneesh Kumar K.V	  userspace file servers, which now track files using handles instead
247990d6c2dSAneesh Kumar K.V	  of names. The handle would remain the same even if file names
248990d6c2dSAneesh Kumar K.V	  get renamed. Enables open_by_handle_at(2) and name_to_handle_at(2)
249990d6c2dSAneesh Kumar K.V	  syscalls.
250990d6c2dSAneesh Kumar K.V
2511da177e4SLinus Torvaldsconfig AUDIT
2521da177e4SLinus Torvalds	bool "Auditing support"
253804a6a49SChris Wright	depends on NET
2541da177e4SLinus Torvalds	help
2551da177e4SLinus Torvalds	  Enable auditing infrastructure that can be used with another
2561da177e4SLinus Torvalds	  kernel subsystem, such as SELinux (which requires this for
2571da177e4SLinus Torvalds	  logging of avc messages output).  Does not do system-call
2581da177e4SLinus Torvalds	  auditing without CONFIG_AUDITSYSCALL.
2591da177e4SLinus Torvalds
2601da177e4SLinus Torvaldsconfig AUDITSYSCALL
2611da177e4SLinus Torvalds	bool "Enable system-call auditing support"
2628f827a14SWill Deacon	depends on AUDIT && (X86 || PPC || S390 || IA64 || UML || SPARC64 || SUPERH || (ARM && AEABI && !OABI_COMPAT))
2631da177e4SLinus Torvalds	default y if SECURITY_SELINUX
2641da177e4SLinus Torvalds	help
2651da177e4SLinus Torvalds	  Enable low-overhead system-call auditing infrastructure that
2661da177e4SLinus Torvalds	  can be used independently or with another kernel subsystem,
26767640b60SEric Paris	  such as SELinux.
2681da177e4SLinus Torvalds
269939a67fcSEric Parisconfig AUDIT_WATCH
270939a67fcSEric Paris	def_bool y
271939a67fcSEric Paris	depends on AUDITSYSCALL
272939a67fcSEric Paris	select FSNOTIFY
2731da177e4SLinus Torvalds
27474c3cbe3SAl Viroconfig AUDIT_TREE
27574c3cbe3SAl Viro	def_bool y
27663c882a0SEric Paris	depends on AUDITSYSCALL
27728a3a7ebSEric Paris	select FSNOTIFY
27874c3cbe3SAl Viro
279633b4545SEric Parisconfig AUDIT_LOGINUID_IMMUTABLE
280633b4545SEric Paris	bool "Make audit loginuid immutable"
281633b4545SEric Paris	depends on AUDIT
282633b4545SEric Paris	help
283f429ee3bSLinus Torvalds	  The config option toggles if a task setting its loginuid requires
284633b4545SEric Paris	  CAP_SYS_AUDITCONTROL or if that task should require no special permissions
285633b4545SEric Paris	  but should instead only allow setting its loginuid if it was never
286633b4545SEric Paris	  previously set.  On systems which use systemd or a similar central
287633b4545SEric Paris	  process to restart login services this should be set to true.  On older
288633b4545SEric Paris	  systems in which an admin would typically have to directly stop and
289633b4545SEric Paris	  start processes this should be set to false.  Setting this to true allows
290633b4545SEric Paris	  one to drop potentially dangerous capabilites from the login tasks,
291633b4545SEric Paris	  but may not be backwards compatible with older init systems.
292633b4545SEric Paris
293d9817ebeSThomas Gleixnersource "kernel/irq/Kconfig"
294764e0da1SThomas Gleixnersource "kernel/time/Kconfig"
295d9817ebeSThomas Gleixner
296391dc69cSFrederic Weisbeckermenu "CPU/Task time and stats accounting"
297391dc69cSFrederic Weisbecker
298abf917cdSFrederic Weisbeckerconfig VIRT_CPU_ACCOUNTING
299abf917cdSFrederic Weisbecker	bool
300abf917cdSFrederic Weisbecker
301fdf9c356SFrederic Weisbeckerchoice
302fdf9c356SFrederic Weisbecker	prompt "Cputime accounting"
303fdf9c356SFrederic Weisbecker	default TICK_CPU_ACCOUNTING if !PPC64
30402fc8d37SStephen Rothwell	default VIRT_CPU_ACCOUNTING_NATIVE if PPC64
305fdf9c356SFrederic Weisbecker
306fdf9c356SFrederic Weisbecker# Kind of a stub config for the pure tick based cputime accounting
307fdf9c356SFrederic Weisbeckerconfig TICK_CPU_ACCOUNTING
308fdf9c356SFrederic Weisbecker	bool "Simple tick based cputime accounting"
309fdf9c356SFrederic Weisbecker	depends on !S390
310fdf9c356SFrederic Weisbecker	help
311fdf9c356SFrederic Weisbecker	  This is the basic tick based cputime accounting that maintains
312fdf9c356SFrederic Weisbecker	  statistics about user, system and idle time spent on per jiffies
313fdf9c356SFrederic Weisbecker	  granularity.
314fdf9c356SFrederic Weisbecker
315fdf9c356SFrederic Weisbecker	  If unsure, say Y.
316fdf9c356SFrederic Weisbecker
317abf917cdSFrederic Weisbeckerconfig VIRT_CPU_ACCOUNTING_NATIVE
318391dc69cSFrederic Weisbecker	bool "Deterministic task and CPU time accounting"
319391dc69cSFrederic Weisbecker	depends on HAVE_VIRT_CPU_ACCOUNTING
320abf917cdSFrederic Weisbecker	select VIRT_CPU_ACCOUNTING
321391dc69cSFrederic Weisbecker	help
322391dc69cSFrederic Weisbecker	  Select this option to enable more accurate task and CPU time
323391dc69cSFrederic Weisbecker	  accounting.  This is done by reading a CPU counter on each
324391dc69cSFrederic Weisbecker	  kernel entry and exit and on transitions within the kernel
325391dc69cSFrederic Weisbecker	  between system, softirq and hardirq state, so there is a
326391dc69cSFrederic Weisbecker	  small performance impact.  In the case of s390 or IBM POWER > 5,
327391dc69cSFrederic Weisbecker	  this also enables accounting of stolen time on logically-partitioned
328391dc69cSFrederic Weisbecker	  systems.
329391dc69cSFrederic Weisbecker
330abf917cdSFrederic Weisbeckerconfig VIRT_CPU_ACCOUNTING_GEN
331abf917cdSFrederic Weisbecker	bool "Full dynticks CPU time accounting"
332abf917cdSFrederic Weisbecker	depends on HAVE_CONTEXT_TRACKING && 64BIT
333abf917cdSFrederic Weisbecker	select VIRT_CPU_ACCOUNTING
334abf917cdSFrederic Weisbecker	select CONTEXT_TRACKING
335abf917cdSFrederic Weisbecker	help
336abf917cdSFrederic Weisbecker	  Select this option to enable task and CPU time accounting on full
337abf917cdSFrederic Weisbecker	  dynticks systems. This accounting is implemented by watching every
338abf917cdSFrederic Weisbecker	  kernel-user boundaries using the context tracking subsystem.
339abf917cdSFrederic Weisbecker	  The accounting is thus performed at the expense of some significant
340abf917cdSFrederic Weisbecker	  overhead.
341abf917cdSFrederic Weisbecker
342abf917cdSFrederic Weisbecker	  For now this is only useful if you are working on the full
343abf917cdSFrederic Weisbecker	  dynticks subsystem development.
344abf917cdSFrederic Weisbecker
345abf917cdSFrederic Weisbecker	  If unsure, say N.
346abf917cdSFrederic Weisbecker
347fdf9c356SFrederic Weisbeckerconfig IRQ_TIME_ACCOUNTING
348fdf9c356SFrederic Weisbecker	bool "Fine granularity task level IRQ time accounting"
349fdf9c356SFrederic Weisbecker	depends on HAVE_IRQ_TIME_ACCOUNTING
350fdf9c356SFrederic Weisbecker	help
351fdf9c356SFrederic Weisbecker	  Select this option to enable fine granularity task irq time
352fdf9c356SFrederic Weisbecker	  accounting. This is done by reading a timestamp on each
353fdf9c356SFrederic Weisbecker	  transitions between softirq and hardirq state, so there can be a
354fdf9c356SFrederic Weisbecker	  small performance impact.
355fdf9c356SFrederic Weisbecker
356fdf9c356SFrederic Weisbecker	  If in doubt, say N here.
357fdf9c356SFrederic Weisbecker
358fdf9c356SFrederic Weisbeckerendchoice
359fdf9c356SFrederic Weisbecker
360391dc69cSFrederic Weisbeckerconfig BSD_PROCESS_ACCT
361391dc69cSFrederic Weisbecker	bool "BSD Process Accounting"
362391dc69cSFrederic Weisbecker	help
363391dc69cSFrederic Weisbecker	  If you say Y here, a user level program will be able to instruct the
364391dc69cSFrederic Weisbecker	  kernel (via a special system call) to write process accounting
365391dc69cSFrederic Weisbecker	  information to a file: whenever a process exits, information about
366391dc69cSFrederic Weisbecker	  that process will be appended to the file by the kernel.  The
367391dc69cSFrederic Weisbecker	  information includes things such as creation time, owning user,
368391dc69cSFrederic Weisbecker	  command name, memory usage, controlling terminal etc. (the complete
369391dc69cSFrederic Weisbecker	  list is in the struct acct in <file:include/linux/acct.h>).  It is
370391dc69cSFrederic Weisbecker	  up to the user level program to do useful things with this
371391dc69cSFrederic Weisbecker	  information.  This is generally a good idea, so say Y.
372391dc69cSFrederic Weisbecker
373391dc69cSFrederic Weisbeckerconfig BSD_PROCESS_ACCT_V3
374391dc69cSFrederic Weisbecker	bool "BSD Process Accounting version 3 file format"
375391dc69cSFrederic Weisbecker	depends on BSD_PROCESS_ACCT
376391dc69cSFrederic Weisbecker	default n
377391dc69cSFrederic Weisbecker	help
378391dc69cSFrederic Weisbecker	  If you say Y here, the process accounting information is written
379391dc69cSFrederic Weisbecker	  in a new file format that also logs the process IDs of each
380391dc69cSFrederic Weisbecker	  process and it's parent. Note that this file format is incompatible
381391dc69cSFrederic Weisbecker	  with previous v0/v1/v2 file formats, so you will need updated tools
382391dc69cSFrederic Weisbecker	  for processing it. A preliminary version of these tools is available
383391dc69cSFrederic Weisbecker	  at <http://www.gnu.org/software/acct/>.
384391dc69cSFrederic Weisbecker
385391dc69cSFrederic Weisbeckerconfig TASKSTATS
38619c92399SKees Cook	bool "Export task/process statistics through netlink"
387391dc69cSFrederic Weisbecker	depends on NET
388391dc69cSFrederic Weisbecker	default n
389391dc69cSFrederic Weisbecker	help
390391dc69cSFrederic Weisbecker	  Export selected statistics for tasks/processes through the
391391dc69cSFrederic Weisbecker	  generic netlink interface. Unlike BSD process accounting, the
392391dc69cSFrederic Weisbecker	  statistics are available during the lifetime of tasks/processes as
393391dc69cSFrederic Weisbecker	  responses to commands. Like BSD accounting, they are sent to user
394391dc69cSFrederic Weisbecker	  space on task exit.
395391dc69cSFrederic Weisbecker
396391dc69cSFrederic Weisbecker	  Say N if unsure.
397391dc69cSFrederic Weisbecker
398391dc69cSFrederic Weisbeckerconfig TASK_DELAY_ACCT
39919c92399SKees Cook	bool "Enable per-task delay accounting"
400391dc69cSFrederic Weisbecker	depends on TASKSTATS
401391dc69cSFrederic Weisbecker	help
402391dc69cSFrederic Weisbecker	  Collect information on time spent by a task waiting for system
403391dc69cSFrederic Weisbecker	  resources like cpu, synchronous block I/O completion and swapping
404391dc69cSFrederic Weisbecker	  in pages. Such statistics can help in setting a task's priorities
405391dc69cSFrederic Weisbecker	  relative to other tasks for cpu, io, rss limits etc.
406391dc69cSFrederic Weisbecker
407391dc69cSFrederic Weisbecker	  Say N if unsure.
408391dc69cSFrederic Weisbecker
409391dc69cSFrederic Weisbeckerconfig TASK_XACCT
41019c92399SKees Cook	bool "Enable extended accounting over taskstats"
411391dc69cSFrederic Weisbecker	depends on TASKSTATS
412391dc69cSFrederic Weisbecker	help
413391dc69cSFrederic Weisbecker	  Collect extended task accounting data and send the data
414391dc69cSFrederic Weisbecker	  to userland for processing over the taskstats interface.
415391dc69cSFrederic Weisbecker
416391dc69cSFrederic Weisbecker	  Say N if unsure.
417391dc69cSFrederic Weisbecker
418391dc69cSFrederic Weisbeckerconfig TASK_IO_ACCOUNTING
41919c92399SKees Cook	bool "Enable per-task storage I/O accounting"
420391dc69cSFrederic Weisbecker	depends on TASK_XACCT
421391dc69cSFrederic Weisbecker	help
422391dc69cSFrederic Weisbecker	  Collect information on the number of bytes of storage I/O which this
423391dc69cSFrederic Weisbecker	  task has caused.
424391dc69cSFrederic Weisbecker
425391dc69cSFrederic Weisbecker	  Say N if unsure.
426391dc69cSFrederic Weisbecker
427391dc69cSFrederic Weisbeckerendmenu # "CPU/Task time and stats accounting"
428391dc69cSFrederic Weisbecker
429c903ff83SMike Travismenu "RCU Subsystem"
430c903ff83SMike Travis
431c903ff83SMike Travischoice
432c903ff83SMike Travis	prompt "RCU Implementation"
43331c9a24eSPaul E. McKenney	default TREE_RCU
434c903ff83SMike Travis
435c903ff83SMike Travisconfig TREE_RCU
436c903ff83SMike Travis	bool "Tree-based hierarchical RCU"
437687d7a96SPaul E. McKenney	depends on !PREEMPT && SMP
438c903ff83SMike Travis	help
439c903ff83SMike Travis	  This option selects the RCU implementation that is
440c903ff83SMike Travis	  designed for very large SMP system with hundreds or
441c17ef453SPaul E. McKenney	  thousands of CPUs.  It also scales down nicely to
442c17ef453SPaul E. McKenney	  smaller systems.
443c903ff83SMike Travis
444f41d911fSPaul E. McKenneyconfig TREE_PREEMPT_RCU
445a57eb940SPaul E. McKenney	bool "Preemptible tree-based hierarchical RCU"
4469fc52d83SPaul E. McKenney	depends on PREEMPT
447f41d911fSPaul E. McKenney	help
448f41d911fSPaul E. McKenney	  This option selects the RCU implementation that is
449f41d911fSPaul E. McKenney	  designed for very large SMP systems with hundreds or
450f41d911fSPaul E. McKenney	  thousands of CPUs, but for which real-time response
451bbe3eae8SPaul E. McKenney	  is also required.  It also scales down nicely to
452bbe3eae8SPaul E. McKenney	  smaller systems.
453f41d911fSPaul E. McKenney
4549fc52d83SPaul E. McKenney	  Select this option if you are unsure.
4559fc52d83SPaul E. McKenney
4569b1d82faSPaul E. McKenneyconfig TINY_RCU
4579b1d82faSPaul E. McKenney	bool "UP-only small-memory-footprint RCU"
4588008e129SPaul E. McKenney	depends on !PREEMPT && !SMP
4599b1d82faSPaul E. McKenney	help
4609b1d82faSPaul E. McKenney	  This option selects the RCU implementation that is
4619b1d82faSPaul E. McKenney	  designed for UP systems from which real-time response
4629b1d82faSPaul E. McKenney	  is not required.  This option greatly reduces the
4639b1d82faSPaul E. McKenney	  memory footprint of RCU.
4649b1d82faSPaul E. McKenney
465a57eb940SPaul E. McKenneyconfig TINY_PREEMPT_RCU
466a57eb940SPaul E. McKenney	bool "Preemptible UP-only small-memory-footprint RCU"
4678008e129SPaul E. McKenney	depends on PREEMPT && !SMP
468a57eb940SPaul E. McKenney	help
469a57eb940SPaul E. McKenney	  This option selects the RCU implementation that is designed
470a57eb940SPaul E. McKenney	  for real-time UP systems.  This option greatly reduces the
471a57eb940SPaul E. McKenney	  memory footprint of RCU.
472a57eb940SPaul E. McKenney
473c903ff83SMike Travisendchoice
474c903ff83SMike Travis
475a57eb940SPaul E. McKenneyconfig PREEMPT_RCU
476a57eb940SPaul E. McKenney	def_bool ( TREE_PREEMPT_RCU || TINY_PREEMPT_RCU )
477a57eb940SPaul E. McKenney	help
478a57eb940SPaul E. McKenney	  This option enables preemptible-RCU code that is common between
479a57eb940SPaul E. McKenney	  the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations.
480a57eb940SPaul E. McKenney
4816bfc09e2SPaul E. McKenneyconfig RCU_STALL_COMMON
4826bfc09e2SPaul E. McKenney	def_bool ( TREE_RCU || TREE_PREEMPT_RCU || RCU_TRACE )
4836bfc09e2SPaul E. McKenney	help
4846bfc09e2SPaul E. McKenney	  This option enables RCU CPU stall code that is common between
4856bfc09e2SPaul E. McKenney	  the TINY and TREE variants of RCU.  The purpose is to allow
4866bfc09e2SPaul E. McKenney	  the tiny variants to disable RCU CPU stall warnings, while
4876bfc09e2SPaul E. McKenney	  making these warnings mandatory for the tree variants.
4886bfc09e2SPaul E. McKenney
48991d1aa43SFrederic Weisbeckerconfig CONTEXT_TRACKING
49091d1aa43SFrederic Weisbecker       bool
49191d1aa43SFrederic Weisbecker
4922b1d5024SFrederic Weisbeckerconfig RCU_USER_QS
4932b1d5024SFrederic Weisbecker	bool "Consider userspace as in RCU extended quiescent state"
49491d1aa43SFrederic Weisbecker	depends on HAVE_CONTEXT_TRACKING && SMP
49591d1aa43SFrederic Weisbecker	select CONTEXT_TRACKING
4962b1d5024SFrederic Weisbecker	help
4972b1d5024SFrederic Weisbecker	  This option sets hooks on kernel / userspace boundaries and
4982b1d5024SFrederic Weisbecker	  puts RCU in extended quiescent state when the CPU runs in
4992b1d5024SFrederic Weisbecker	  userspace. It means that when a CPU runs in userspace, it is
5002b1d5024SFrederic Weisbecker	  excluded from the global RCU state machine and thus doesn't
501af71befaSPaul Gortmaker	  try to keep the timer tick on for RCU.
5022b1d5024SFrederic Weisbecker
503d677124bSFrederic Weisbecker	  Unless you want to hack and help the development of the full
50491d1aa43SFrederic Weisbecker	  dynticks mode, you shouldn't enable this option.  It also
505af71befaSPaul Gortmaker	  adds unnecessary overhead.
506d677124bSFrederic Weisbecker
507d677124bSFrederic Weisbecker	  If unsure say N
508d677124bSFrederic Weisbecker
50991d1aa43SFrederic Weisbeckerconfig CONTEXT_TRACKING_FORCE
51091d1aa43SFrederic Weisbecker	bool "Force context tracking"
51191d1aa43SFrederic Weisbecker	depends on CONTEXT_TRACKING
512*8b438766SFrederic Weisbecker	default CONTEXT_TRACKING
5131fd2b442SFrederic Weisbecker	help
51491d1aa43SFrederic Weisbecker	  Probe on user/kernel boundaries by default in order to
51591d1aa43SFrederic Weisbecker	  test the features that rely on it such as userspace RCU extended
51691d1aa43SFrederic Weisbecker	  quiescent states.
51791d1aa43SFrederic Weisbecker	  This test is there for debugging until we have a real user like the
51891d1aa43SFrederic Weisbecker	  full dynticks mode.
519d677124bSFrederic Weisbecker
520c903ff83SMike Travisconfig RCU_FANOUT
521c903ff83SMike Travis	int "Tree-based hierarchical RCU fanout value"
522c903ff83SMike Travis	range 2 64 if 64BIT
523c903ff83SMike Travis	range 2 32 if !64BIT
524f41d911fSPaul E. McKenney	depends on TREE_RCU || TREE_PREEMPT_RCU
525c903ff83SMike Travis	default 64 if 64BIT
526c903ff83SMike Travis	default 32 if !64BIT
527c903ff83SMike Travis	help
528c903ff83SMike Travis	  This option controls the fanout of hierarchical implementations
529c903ff83SMike Travis	  of RCU, allowing RCU to work efficiently on machines with
5304d87ffadSPaul E. McKenney	  large numbers of CPUs.  This value must be at least the fourth
5314d87ffadSPaul E. McKenney	  root of NR_CPUS, which allows NR_CPUS to be insanely large.
5324d87ffadSPaul E. McKenney	  The default value of RCU_FANOUT should be used for production
5334d87ffadSPaul E. McKenney	  systems, but if you are stress-testing the RCU implementation
5344d87ffadSPaul E. McKenney	  itself, small RCU_FANOUT values allow you to test large-system
5354d87ffadSPaul E. McKenney	  code paths on small(er) systems.
536c903ff83SMike Travis
537c903ff83SMike Travis	  Select a specific number if testing RCU itself.
538c903ff83SMike Travis	  Take the default if unsure.
539c903ff83SMike Travis
5408932a63dSPaul E. McKenneyconfig RCU_FANOUT_LEAF
5418932a63dSPaul E. McKenney	int "Tree-based hierarchical RCU leaf-level fanout value"
5428932a63dSPaul E. McKenney	range 2 RCU_FANOUT if 64BIT
5438932a63dSPaul E. McKenney	range 2 RCU_FANOUT if !64BIT
5448932a63dSPaul E. McKenney	depends on TREE_RCU || TREE_PREEMPT_RCU
5458932a63dSPaul E. McKenney	default 16
5468932a63dSPaul E. McKenney	help
5478932a63dSPaul E. McKenney	  This option controls the leaf-level fanout of hierarchical
5488932a63dSPaul E. McKenney	  implementations of RCU, and allows trading off cache misses
5498932a63dSPaul E. McKenney	  against lock contention.  Systems that synchronize their
5508932a63dSPaul E. McKenney	  scheduling-clock interrupts for energy-efficiency reasons will
5518932a63dSPaul E. McKenney	  want the default because the smaller leaf-level fanout keeps
5528932a63dSPaul E. McKenney	  lock contention levels acceptably low.  Very large systems
5538932a63dSPaul E. McKenney	  (hundreds or thousands of CPUs) will instead want to set this
5548932a63dSPaul E. McKenney	  value to the maximum value possible in order to reduce the
5558932a63dSPaul E. McKenney	  number of cache misses incurred during RCU's grace-period
5568932a63dSPaul E. McKenney	  initialization.  These systems tend to run CPU-bound, and thus
5578932a63dSPaul E. McKenney	  are not helped by synchronized interrupts, and thus tend to
5588932a63dSPaul E. McKenney	  skew them, which reduces lock contention enough that large
5598932a63dSPaul E. McKenney	  leaf-level fanouts work well.
5608932a63dSPaul E. McKenney
5618932a63dSPaul E. McKenney	  Select a specific number if testing RCU itself.
5628932a63dSPaul E. McKenney
5638932a63dSPaul E. McKenney	  Select the maximum permissible value for large systems.
5648932a63dSPaul E. McKenney
5658932a63dSPaul E. McKenney	  Take the default if unsure.
5668932a63dSPaul E. McKenney
567c903ff83SMike Travisconfig RCU_FANOUT_EXACT
568c903ff83SMike Travis	bool "Disable tree-based hierarchical RCU auto-balancing"
569f41d911fSPaul E. McKenney	depends on TREE_RCU || TREE_PREEMPT_RCU
570c903ff83SMike Travis	default n
571c903ff83SMike Travis	help
572c903ff83SMike Travis	  This option forces use of the exact RCU_FANOUT value specified,
573c903ff83SMike Travis	  regardless of imbalances in the hierarchy.  This is useful for
574c903ff83SMike Travis	  testing RCU itself, and might one day be useful on systems with
575c903ff83SMike Travis	  strong NUMA behavior.
576c903ff83SMike Travis
577c903ff83SMike Travis	  Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
578c903ff83SMike Travis
579c903ff83SMike Travis	  Say N if unsure.
580c903ff83SMike Travis
5818bd93a2cSPaul E. McKenneyconfig RCU_FAST_NO_HZ
5828bd93a2cSPaul E. McKenney	bool "Accelerate last non-dyntick-idle CPU's grace periods"
583b807fbffSPaul E. McKenney	depends on NO_HZ && SMP
5848bd93a2cSPaul E. McKenney	default n
5858bd93a2cSPaul E. McKenney	help
586ba49df47SPaul E. McKenney	  This option causes RCU to attempt to accelerate grace periods in
587ba49df47SPaul E. McKenney	  order to allow CPUs to enter dynticks-idle state more quickly.
588ba49df47SPaul E. McKenney	  On the other hand, this option increases the overhead of the
589ba49df47SPaul E. McKenney	  dynticks-idle checking, thus degrading scheduling latency.
5908bd93a2cSPaul E. McKenney
591ba49df47SPaul E. McKenney	  Say Y if energy efficiency is critically important, and you don't
592ba49df47SPaul E. McKenney	  	care about real-time response.
5938bd93a2cSPaul E. McKenney
5948bd93a2cSPaul E. McKenney	  Say N if you are unsure.
5958bd93a2cSPaul E. McKenney
596c903ff83SMike Travisconfig TREE_RCU_TRACE
597f41d911fSPaul E. McKenney	def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
598c903ff83SMike Travis	select DEBUG_FS
599c903ff83SMike Travis	help
600f41d911fSPaul E. McKenney	  This option provides tracing for the TREE_RCU and
601f41d911fSPaul E. McKenney	  TREE_PREEMPT_RCU implementations, permitting Makefile to
602f41d911fSPaul E. McKenney	  trivially select kernel/rcutree_trace.c.
603c903ff83SMike Travis
60424278d14SPaul E. McKenneyconfig RCU_BOOST
60524278d14SPaul E. McKenney	bool "Enable RCU priority boosting"
60627f4d280SPaul E. McKenney	depends on RT_MUTEXES && PREEMPT_RCU
60724278d14SPaul E. McKenney	default n
60824278d14SPaul E. McKenney	help
60924278d14SPaul E. McKenney	  This option boosts the priority of preempted RCU readers that
61024278d14SPaul E. McKenney	  block the current preemptible RCU grace period for too long.
61124278d14SPaul E. McKenney	  This option also prevents heavy loads from blocking RCU
61224278d14SPaul E. McKenney	  callback invocation for all flavors of RCU.
61324278d14SPaul E. McKenney
61424278d14SPaul E. McKenney	  Say Y here if you are working with real-time apps or heavy loads
61524278d14SPaul E. McKenney	  Say N here if you are unsure.
61624278d14SPaul E. McKenney
61724278d14SPaul E. McKenneyconfig RCU_BOOST_PRIO
61824278d14SPaul E. McKenney	int "Real-time priority to boost RCU readers to"
61924278d14SPaul E. McKenney	range 1 99
62024278d14SPaul E. McKenney	depends on RCU_BOOST
62124278d14SPaul E. McKenney	default 1
62224278d14SPaul E. McKenney	help
623c9336643SPaul E. McKenney	  This option specifies the real-time priority to which long-term
624c9336643SPaul E. McKenney	  preempted RCU readers are to be boosted.  If you are working
625c9336643SPaul E. McKenney	  with a real-time application that has one or more CPU-bound
626c9336643SPaul E. McKenney	  threads running at a real-time priority level, you should set
627c9336643SPaul E. McKenney	  RCU_BOOST_PRIO to a priority higher then the highest-priority
628c9336643SPaul E. McKenney	  real-time CPU-bound thread.  The default RCU_BOOST_PRIO value
629c9336643SPaul E. McKenney	  of 1 is appropriate in the common case, which is real-time
630c9336643SPaul E. McKenney	  applications that do not have any CPU-bound threads.
631c9336643SPaul E. McKenney
632c9336643SPaul E. McKenney	  Some real-time applications might not have a single real-time
633c9336643SPaul E. McKenney	  thread that saturates a given CPU, but instead might have
634c9336643SPaul E. McKenney	  multiple real-time threads that, taken together, fully utilize
635c9336643SPaul E. McKenney	  that CPU.  In this case, you should set RCU_BOOST_PRIO to
636c9336643SPaul E. McKenney	  a priority higher than the lowest-priority thread that is
637c9336643SPaul E. McKenney	  conspiring to prevent the CPU from running any non-real-time
638c9336643SPaul E. McKenney	  tasks.  For example, if one thread at priority 10 and another
639c9336643SPaul E. McKenney	  thread at priority 5 are between themselves fully consuming
640c9336643SPaul E. McKenney	  the CPU time on a given CPU, then RCU_BOOST_PRIO should be
641c9336643SPaul E. McKenney	  set to priority 6 or higher.
64224278d14SPaul E. McKenney
64324278d14SPaul E. McKenney	  Specify the real-time priority, or take the default if unsure.
64424278d14SPaul E. McKenney
64524278d14SPaul E. McKenneyconfig RCU_BOOST_DELAY
64624278d14SPaul E. McKenney	int "Milliseconds to delay boosting after RCU grace-period start"
64724278d14SPaul E. McKenney	range 0 3000
64824278d14SPaul E. McKenney	depends on RCU_BOOST
64924278d14SPaul E. McKenney	default 500
65024278d14SPaul E. McKenney	help
65124278d14SPaul E. McKenney	  This option specifies the time to wait after the beginning of
65224278d14SPaul E. McKenney	  a given grace period before priority-boosting preempted RCU
65324278d14SPaul E. McKenney	  readers blocking that grace period.  Note that any RCU reader
65424278d14SPaul E. McKenney	  blocking an expedited RCU grace period is boosted immediately.
65524278d14SPaul E. McKenney
65624278d14SPaul E. McKenney	  Accept the default if unsure.
65724278d14SPaul E. McKenney
6583fbfbf7aSPaul E. McKenneyconfig RCU_NOCB_CPU
6593fbfbf7aSPaul E. McKenney	bool "Offload RCU callback processing from boot-selected CPUs"
6603fbfbf7aSPaul E. McKenney	depends on TREE_RCU || TREE_PREEMPT_RCU
6613fbfbf7aSPaul E. McKenney	default n
6623fbfbf7aSPaul E. McKenney	help
6633fbfbf7aSPaul E. McKenney	  Use this option to reduce OS jitter for aggressive HPC or
6643fbfbf7aSPaul E. McKenney	  real-time workloads.	It can also be used to offload RCU
6653fbfbf7aSPaul E. McKenney	  callback invocation to energy-efficient CPUs in battery-powered
6663fbfbf7aSPaul E. McKenney	  asymmetric multiprocessors.
6673fbfbf7aSPaul E. McKenney
6683fbfbf7aSPaul E. McKenney	  This option offloads callback invocation from the set of
6693fbfbf7aSPaul E. McKenney	  CPUs specified at boot time by the rcu_nocbs parameter.
6703fbfbf7aSPaul E. McKenney	  For each such CPU, a kthread ("rcuoN") will be created to
6713fbfbf7aSPaul E. McKenney	  invoke callbacks, where the "N" is the CPU being offloaded.
6723fbfbf7aSPaul E. McKenney	  Nothing prevents this kthread from running on the specified
6733fbfbf7aSPaul E. McKenney	  CPUs, but (1) the kthreads may be preempted between each
6743fbfbf7aSPaul E. McKenney	  callback, and (2) affinity or cgroups can be used to force
6753fbfbf7aSPaul E. McKenney	  the kthreads to run on whatever set of CPUs is desired.
6763fbfbf7aSPaul E. McKenney
6773fbfbf7aSPaul E. McKenney	  Say Y here if you want reduced OS jitter on selected CPUs.
6783fbfbf7aSPaul E. McKenney	  Say N here if you are unsure.
6793fbfbf7aSPaul E. McKenney
680c903ff83SMike Travisendmenu # "RCU Subsystem"
681c903ff83SMike Travis
6821da177e4SLinus Torvaldsconfig IKCONFIG
683f2443ab6SRoss Biro	tristate "Kernel .config support"
6841da177e4SLinus Torvalds	---help---
6851da177e4SLinus Torvalds	  This option enables the complete Linux kernel ".config" file
6861da177e4SLinus Torvalds	  contents to be saved in the kernel. It provides documentation
6871da177e4SLinus Torvalds	  of which kernel options are used in a running kernel or in an
6881da177e4SLinus Torvalds	  on-disk kernel.  This information can be extracted from the kernel
6891da177e4SLinus Torvalds	  image file with the script scripts/extract-ikconfig and used as
6901da177e4SLinus Torvalds	  input to rebuild the current kernel or to build another kernel.
6911da177e4SLinus Torvalds	  It can also be extracted from a running kernel by reading
6921da177e4SLinus Torvalds	  /proc/config.gz if enabled (below).
6931da177e4SLinus Torvalds
6941da177e4SLinus Torvaldsconfig IKCONFIG_PROC
6951da177e4SLinus Torvalds	bool "Enable access to .config through /proc/config.gz"
6961da177e4SLinus Torvalds	depends on IKCONFIG && PROC_FS
6971da177e4SLinus Torvalds	---help---
6981da177e4SLinus Torvalds	  This option enables access to the kernel configuration file
6991da177e4SLinus Torvalds	  through /proc/config.gz.
7001da177e4SLinus Torvalds
701794543a2SAlistair John Strachanconfig LOG_BUF_SHIFT
702794543a2SAlistair John Strachan	int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
703794543a2SAlistair John Strachan	range 12 21
704f17a32e9SAdrian Bunk	default 17
705794543a2SAlistair John Strachan	help
706794543a2SAlistair John Strachan	  Select kernel log buffer size as a power of 2.
707f17a32e9SAdrian Bunk	  Examples:
708f17a32e9SAdrian Bunk	  	     17 => 128 KB
709f17a32e9SAdrian Bunk		     16 => 64 KB
710f17a32e9SAdrian Bunk	             15 => 32 KB
711f17a32e9SAdrian Bunk	             14 => 16 KB
712794543a2SAlistair John Strachan		     13 =>  8 KB
713794543a2SAlistair John Strachan		     12 =>  4 KB
714794543a2SAlistair John Strachan
7155cdc38f9SKAMEZAWA Hiroyuki#
7165cdc38f9SKAMEZAWA Hiroyuki# Architectures with an unreliable sched_clock() should select this:
7175cdc38f9SKAMEZAWA Hiroyuki#
7185cdc38f9SKAMEZAWA Hiroyukiconfig HAVE_UNSTABLE_SCHED_CLOCK
7195cdc38f9SKAMEZAWA Hiroyuki	bool
7205cdc38f9SKAMEZAWA Hiroyuki
721be3a7284SAndrea Arcangeli#
722be3a7284SAndrea Arcangeli# For architectures that want to enable the support for NUMA-affine scheduler
723be3a7284SAndrea Arcangeli# balancing logic:
724be3a7284SAndrea Arcangeli#
725be3a7284SAndrea Arcangeliconfig ARCH_SUPPORTS_NUMA_BALANCING
726be3a7284SAndrea Arcangeli	bool
727be3a7284SAndrea Arcangeli
728be3a7284SAndrea Arcangeli# For architectures that (ab)use NUMA to represent different memory regions
729be3a7284SAndrea Arcangeli# all cpu-local but of different latencies, such as SuperH.
730be3a7284SAndrea Arcangeli#
731be3a7284SAndrea Arcangeliconfig ARCH_WANT_NUMA_VARIABLE_LOCALITY
732be3a7284SAndrea Arcangeli	bool
733be3a7284SAndrea Arcangeli
734be3a7284SAndrea Arcangeli#
735be3a7284SAndrea Arcangeli# For architectures that are willing to define _PAGE_NUMA as _PAGE_PROTNONE
736be3a7284SAndrea Arcangeliconfig ARCH_WANTS_PROT_NUMA_PROT_NONE
737be3a7284SAndrea Arcangeli	bool
738be3a7284SAndrea Arcangeli
739be3a7284SAndrea Arcangeliconfig ARCH_USES_NUMA_PROT_NONE
740be3a7284SAndrea Arcangeli	bool
741be3a7284SAndrea Arcangeli	default y
742be3a7284SAndrea Arcangeli	depends on ARCH_WANTS_PROT_NUMA_PROT_NONE
743be3a7284SAndrea Arcangeli	depends on NUMA_BALANCING
744be3a7284SAndrea Arcangeli
7451a687c2eSMel Gormanconfig NUMA_BALANCING_DEFAULT_ENABLED
7461a687c2eSMel Gorman	bool "Automatically enable NUMA aware memory/task placement"
7471a687c2eSMel Gorman	default y
7481a687c2eSMel Gorman	depends on NUMA_BALANCING
7491a687c2eSMel Gorman	help
7501a687c2eSMel Gorman	  If set, autonumic NUMA balancing will be enabled if running on a NUMA
7511a687c2eSMel Gorman	  machine.
7521a687c2eSMel Gorman
753be3a7284SAndrea Arcangeliconfig NUMA_BALANCING
754be3a7284SAndrea Arcangeli	bool "Memory placement aware NUMA scheduler"
755be3a7284SAndrea Arcangeli	depends on ARCH_SUPPORTS_NUMA_BALANCING
756be3a7284SAndrea Arcangeli	depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY
757be3a7284SAndrea Arcangeli	depends on SMP && NUMA && MIGRATION
758be3a7284SAndrea Arcangeli	help
759be3a7284SAndrea Arcangeli	  This option adds support for automatic NUMA aware memory/task placement.
760be3a7284SAndrea Arcangeli	  The mechanism is quite primitive and is based on migrating memory when
761be3a7284SAndrea Arcangeli	  it is references to the node the task is running on.
762be3a7284SAndrea Arcangeli
763be3a7284SAndrea Arcangeli	  This system will be inactive on UMA systems.
764be3a7284SAndrea Arcangeli
76523964d2dSLi Zefanmenuconfig CGROUPS
76623964d2dSLi Zefan	boolean "Control Group support"
7670dea1168SKirill A. Shutemov	depends on EVENTFD
768ddbcc7e8SPaul Menage	help
76923964d2dSLi Zefan	  This option adds support for grouping sets of processes together, for
7705cdc38f9SKAMEZAWA Hiroyuki	  use with process control subsystems such as Cpusets, CFS, memory
7715cdc38f9SKAMEZAWA Hiroyuki	  controls or device isolation.
7725cdc38f9SKAMEZAWA Hiroyuki	  See
7735cdc38f9SKAMEZAWA Hiroyuki		- Documentation/scheduler/sched-design-CFS.txt	(CFS)
77445ce80fbSLi Zefan		- Documentation/cgroups/ (features for grouping, isolation
77545ce80fbSLi Zefan					  and resource control)
776ddbcc7e8SPaul Menage
777ddbcc7e8SPaul Menage	  Say N if unsure.
778ddbcc7e8SPaul Menage
77923964d2dSLi Zefanif CGROUPS
78023964d2dSLi Zefan
781006cb992SPaul Menageconfig CGROUP_DEBUG
782006cb992SPaul Menage	bool "Example debug cgroup subsystem"
783418d7d87SPaul Menage	default n
784006cb992SPaul Menage	help
785006cb992SPaul Menage	  This option enables a simple cgroup subsystem that
786006cb992SPaul Menage	  exports useful debugging information about the cgroups
78723964d2dSLi Zefan	  framework.
788006cb992SPaul Menage
78923964d2dSLi Zefan	  Say N if unsure.
790006cb992SPaul Menage
791dc52ddc0SMatt Helsleyconfig CGROUP_FREEZER
79223964d2dSLi Zefan	bool "Freezer cgroup subsystem"
793dc52ddc0SMatt Helsley	help
794dc52ddc0SMatt Helsley	  Provides a way to freeze and unfreeze all tasks in a
795dc52ddc0SMatt Helsley	  cgroup.
796dc52ddc0SMatt Helsley
79708ce5f16SSerge E. Hallynconfig CGROUP_DEVICE
79808ce5f16SSerge E. Hallyn	bool "Device controller for cgroups"
79908ce5f16SSerge E. Hallyn	help
80008ce5f16SSerge E. Hallyn	  Provides a cgroup implementing whitelists for devices which
80108ce5f16SSerge E. Hallyn	  a process in the cgroup can mknod or open.
80208ce5f16SSerge E. Hallyn
8031da177e4SLinus Torvaldsconfig CPUSETS
8041da177e4SLinus Torvalds	bool "Cpuset support"
8051da177e4SLinus Torvalds	help
806d9fd8a6dSRandy Dunlap	  This option will let you create and manage CPUSETs which
8071da177e4SLinus Torvalds	  allow dynamically partitioning a system into sets of CPUs and
8081da177e4SLinus Torvalds	  Memory Nodes and assigning tasks to run only within those sets.
8091da177e4SLinus Torvalds	  This is primarily useful on large SMP or NUMA systems.
8101da177e4SLinus Torvalds
8111da177e4SLinus Torvalds	  Say N if unsure.
8121da177e4SLinus Torvalds
81323964d2dSLi Zefanconfig PROC_PID_CPUSET
81423964d2dSLi Zefan	bool "Include legacy /proc/<pid>/cpuset file"
81523964d2dSLi Zefan	depends on CPUSETS
81623964d2dSLi Zefan	default y
81723964d2dSLi Zefan
818d842de87SSrivatsa Vaddagiriconfig CGROUP_CPUACCT
819d842de87SSrivatsa Vaddagiri	bool "Simple CPU accounting cgroup subsystem"
820d842de87SSrivatsa Vaddagiri	help
821d842de87SSrivatsa Vaddagiri	  Provides a simple Resource Controller for monitoring the
82223964d2dSLi Zefan	  total CPU consumed by the tasks in a cgroup.
823d842de87SSrivatsa Vaddagiri
824e552b661SPavel Emelianovconfig RESOURCE_COUNTERS
825e552b661SPavel Emelianov	bool "Resource counters"
826e552b661SPavel Emelianov	help
827e552b661SPavel Emelianov	  This option enables controller independent resource accounting
82823964d2dSLi Zefan	  infrastructure that works with cgroups.
829e552b661SPavel Emelianov
830c255a458SAndrew Mortonconfig MEMCG
83100f0b825SBalbir Singh	bool "Memory Resource Controller for Control Groups"
83279ae9c29SDaniel Lezcano	depends on RESOURCE_COUNTERS
833cf475ad2SBalbir Singh	select MM_OWNER
83400f0b825SBalbir Singh	help
83584ad6d70SKAMEZAWA Hiroyuki	  Provides a memory resource controller that manages both anonymous
83621acb9caSThadeu Lima de Souza Cascardo	  memory and page cache. (See Documentation/cgroups/memory.txt)
83700f0b825SBalbir Singh
83800f0b825SBalbir Singh	  Note that setting this option increases fixed memory overhead
83984ad6d70SKAMEZAWA Hiroyuki	  associated with each page of memory in the system. By this,
84084ad6d70SKAMEZAWA Hiroyuki	  20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
84184ad6d70SKAMEZAWA Hiroyuki	  usage tracking struct at boot. Total amount of this is printed out
84284ad6d70SKAMEZAWA Hiroyuki	  at boot.
84300f0b825SBalbir Singh
84400f0b825SBalbir Singh	  Only enable when you're ok with these trade offs and really
84584ad6d70SKAMEZAWA Hiroyuki	  sure you need the memory resource controller. Even when you enable
84684ad6d70SKAMEZAWA Hiroyuki	  this, you can set "cgroup_disable=memory" at your boot option to
84784ad6d70SKAMEZAWA Hiroyuki	  disable memory resource controller and you can avoid overheads.
848c9d5409fSLi Zefan	  (and lose benefits of memory resource controller)
84900f0b825SBalbir Singh
850cf475ad2SBalbir Singh	  This config option also selects MM_OWNER config option, which
851cf475ad2SBalbir Singh	  could in turn add some fork/exit overhead.
852cf475ad2SBalbir Singh
853c255a458SAndrew Mortonconfig MEMCG_SWAP
85465e0e811SKAMEZAWA Hiroyuki	bool "Memory Resource Controller Swap Extension"
855c255a458SAndrew Morton	depends on MEMCG && SWAP
856c077719bSKAMEZAWA Hiroyuki	help
857c077719bSKAMEZAWA Hiroyuki	  Add swap management feature to memory resource controller. When you
858c077719bSKAMEZAWA Hiroyuki	  enable this, you can limit mem+swap usage per cgroup. In other words,
859c077719bSKAMEZAWA Hiroyuki	  when you disable this, memory resource controller has no cares to
860c077719bSKAMEZAWA Hiroyuki	  usage of swap...a process can exhaust all of the swap. This extension
861c077719bSKAMEZAWA Hiroyuki	  is useful when you want to avoid exhaustion swap but this itself
862c077719bSKAMEZAWA Hiroyuki	  adds more overheads and consumes memory for remembering information.
863c077719bSKAMEZAWA Hiroyuki	  Especially if you use 32bit system or small memory system, please
864c077719bSKAMEZAWA Hiroyuki	  be careful about enabling this. When memory resource controller
865c077719bSKAMEZAWA Hiroyuki	  is disabled by boot option, this will be automatically disabled and
866c077719bSKAMEZAWA Hiroyuki	  there will be no overhead from this. Even when you set this config=y,
86700a66d29SWANG Cong	  if boot option "swapaccount=0" is set, swap will not be accounted.
868627991a2SKAMEZAWA Hiroyuki	  Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
869627991a2SKAMEZAWA Hiroyuki	  size is 4096bytes, 512k per 1Gbytes of swap.
870c255a458SAndrew Mortonconfig MEMCG_SWAP_ENABLED
871a42c390cSMichal Hocko	bool "Memory Resource Controller Swap Extension enabled by default"
872c255a458SAndrew Morton	depends on MEMCG_SWAP
873a42c390cSMichal Hocko	default y
874a42c390cSMichal Hocko	help
875a42c390cSMichal Hocko	  Memory Resource Controller Swap Extension comes with its price in
876a42c390cSMichal Hocko	  a bigger memory consumption. General purpose distribution kernels
87743d547f9SJim Cromie	  which want to enable the feature but keep it disabled by default
878a42c390cSMichal Hocko	  and let the user enable it by swapaccount boot command line
879a42c390cSMichal Hocko	  parameter should have this option unselected.
880a42c390cSMichal Hocko	  For those who want to have the feature enabled by default should
881a42c390cSMichal Hocko	  select this option (if, for some reason, they need to disable it
88200a66d29SWANG Cong	  then swapaccount=0 does the trick).
883c255a458SAndrew Mortonconfig MEMCG_KMEM
88419c92399SKees Cook	bool "Memory Resource Controller Kernel Memory accounting"
88519c92399SKees Cook	depends on MEMCG
886510fc4e1SGlauber Costa	depends on SLUB || SLAB
887e5671dfaSGlauber Costa	help
888e5671dfaSGlauber Costa	  The Kernel Memory extension for Memory Resource Controller can limit
889e5671dfaSGlauber Costa	  the amount of memory used by kernel objects in the system. Those are
890e5671dfaSGlauber Costa	  fundamentally different from the entities handled by the standard
891e5671dfaSGlauber Costa	  Memory Controller, which are page-based, and can be swapped. Users of
892e5671dfaSGlauber Costa	  the kmem extension can use it to guarantee that no group of processes
893e5671dfaSGlauber Costa	  will ever exhaust kernel resources alone.
894c077719bSKAMEZAWA Hiroyuki
8952bc64a20SAneesh Kumar K.Vconfig CGROUP_HUGETLB
8962bc64a20SAneesh Kumar K.V	bool "HugeTLB Resource Controller for Control Groups"
89719c92399SKees Cook	depends on RESOURCE_COUNTERS && HUGETLB_PAGE
8982bc64a20SAneesh Kumar K.V	default n
8992bc64a20SAneesh Kumar K.V	help
9002bc64a20SAneesh Kumar K.V	  Provides a cgroup Resource Controller for HugeTLB pages.
9012bc64a20SAneesh Kumar K.V	  When you enable this, you can put a per cgroup limit on HugeTLB usage.
9022bc64a20SAneesh Kumar K.V	  The limit is enforced during page fault. Since HugeTLB doesn't
9032bc64a20SAneesh Kumar K.V	  support page reclaim, enforcing the limit at page fault time implies
9042bc64a20SAneesh Kumar K.V	  that, the application will get SIGBUS signal if it tries to access
9052bc64a20SAneesh Kumar K.V	  HugeTLB pages beyond its limit. This requires the application to know
9062bc64a20SAneesh Kumar K.V	  beforehand how much HugeTLB pages it would require for its use. The
9072bc64a20SAneesh Kumar K.V	  control group is tracked in the third page lru pointer. This means
9082bc64a20SAneesh Kumar K.V	  that we cannot use the controller with huge page less than 3 pages.
9092bc64a20SAneesh Kumar K.V
910e5d1367fSStephane Eranianconfig CGROUP_PERF
911e5d1367fSStephane Eranian	bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
912e5d1367fSStephane Eranian	depends on PERF_EVENTS && CGROUPS
913e5d1367fSStephane Eranian	help
914e5d1367fSStephane Eranian	  This option extends the per-cpu mode to restrict monitoring to
9152d0f2520SLi Zefan	  threads which belong to the cgroup specified and run on the
916e5d1367fSStephane Eranian	  designated cpu.
917e5d1367fSStephane Eranian
918e5d1367fSStephane Eranian	  Say N if unsure.
919e5d1367fSStephane Eranian
9207c941438SDhaval Gianimenuconfig CGROUP_SCHED
9217c941438SDhaval Giani	bool "Group CPU scheduler"
9227c941438SDhaval Giani	default n
9237c941438SDhaval Giani	help
9247c941438SDhaval Giani	  This feature lets CPU scheduler recognize task groups and control CPU
9257c941438SDhaval Giani	  bandwidth allocation to such task groups. It uses cgroups to group
9267c941438SDhaval Giani	  tasks.
9277c941438SDhaval Giani
9287c941438SDhaval Gianiif CGROUP_SCHED
9297c941438SDhaval Gianiconfig FAIR_GROUP_SCHED
9307c941438SDhaval Giani	bool "Group scheduling for SCHED_OTHER"
9317c941438SDhaval Giani	depends on CGROUP_SCHED
9327c941438SDhaval Giani	default CGROUP_SCHED
9337c941438SDhaval Giani
934ab84d31eSPaul Turnerconfig CFS_BANDWIDTH
935ab84d31eSPaul Turner	bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
936ab84d31eSPaul Turner	depends on FAIR_GROUP_SCHED
937ab84d31eSPaul Turner	default n
938ab84d31eSPaul Turner	help
939ab84d31eSPaul Turner	  This option allows users to define CPU bandwidth rates (limits) for
940ab84d31eSPaul Turner	  tasks running within the fair group scheduler.  Groups with no limit
941ab84d31eSPaul Turner	  set are considered to be unconstrained and will run with no
942ab84d31eSPaul Turner	  restriction.
943ab84d31eSPaul Turner	  See tip/Documentation/scheduler/sched-bwc.txt for more information.
944ab84d31eSPaul Turner
9457c941438SDhaval Gianiconfig RT_GROUP_SCHED
9467c941438SDhaval Giani	bool "Group scheduling for SCHED_RR/FIFO"
9477c941438SDhaval Giani	depends on CGROUP_SCHED
9487c941438SDhaval Giani	default n
9497c941438SDhaval Giani	help
9507c941438SDhaval Giani	  This feature lets you explicitly allocate real CPU bandwidth
95132bd7eb5SLi Zefan	  to task groups. If enabled, it will also make it impossible to
9527c941438SDhaval Giani	  schedule realtime tasks for non-root users until you allocate
9537c941438SDhaval Giani	  realtime bandwidth for them.
9547c941438SDhaval Giani	  See Documentation/scheduler/sched-rt-group.txt for more information.
9557c941438SDhaval Giani
9567c941438SDhaval Gianiendif #CGROUP_SCHED
9577c941438SDhaval Giani
958afc24d49SVivek Goyalconfig BLK_CGROUP
95932e380aeSTejun Heo	bool "Block IO controller"
96079ae9c29SDaniel Lezcano	depends on BLOCK
961afc24d49SVivek Goyal	default n
962afc24d49SVivek Goyal	---help---
963afc24d49SVivek Goyal	Generic block IO controller cgroup interface. This is the common
964afc24d49SVivek Goyal	cgroup interface which should be used by various IO controlling
965afc24d49SVivek Goyal	policies.
966afc24d49SVivek Goyal
967afc24d49SVivek Goyal	Currently, CFQ IO scheduler uses it to recognize task groups and
968afc24d49SVivek Goyal	control disk bandwidth allocation (proportional time slice allocation)
969e43473b7SVivek Goyal	to such task groups. It is also used by bio throttling logic in
970e43473b7SVivek Goyal	block layer to implement upper limit in IO rates on a device.
971afc24d49SVivek Goyal
972afc24d49SVivek Goyal	This option only enables generic Block IO controller infrastructure.
973e43473b7SVivek Goyal	One needs to also enable actual IO controlling logic/policy. For
97479e2e759SMichael Witten	enabling proportional weight division of disk bandwidth in CFQ, set
97579e2e759SMichael Witten	CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
976c5e0591aSMichael Witten	CONFIG_BLK_DEV_THROTTLING=y.
977afc24d49SVivek Goyal
978afc24d49SVivek Goyal	See Documentation/cgroups/blkio-controller.txt for more information.
979afc24d49SVivek Goyal
980afc24d49SVivek Goyalconfig DEBUG_BLK_CGROUP
981afc24d49SVivek Goyal	bool "Enable Block IO controller debugging"
982afc24d49SVivek Goyal	depends on BLK_CGROUP
983afc24d49SVivek Goyal	default n
984afc24d49SVivek Goyal	---help---
985afc24d49SVivek Goyal	Enable some debugging help. Currently it exports additional stat
986afc24d49SVivek Goyal	files in a cgroup which can be useful for debugging.
987afc24d49SVivek Goyal
98823964d2dSLi Zefanendif # CGROUPS
989c077719bSKAMEZAWA Hiroyuki
990067bce1aSCyrill Gorcunovconfig CHECKPOINT_RESTORE
991067bce1aSCyrill Gorcunov	bool "Checkpoint/restore support" if EXPERT
992067bce1aSCyrill Gorcunov	default n
993067bce1aSCyrill Gorcunov	help
994067bce1aSCyrill Gorcunov	  Enables additional kernel features in a sake of checkpoint/restore.
995067bce1aSCyrill Gorcunov	  In particular it adds auxiliary prctl codes to setup process text,
996067bce1aSCyrill Gorcunov	  data and heap segment sizes, and a few additional /proc filesystem
997067bce1aSCyrill Gorcunov	  entries.
998067bce1aSCyrill Gorcunov
999067bce1aSCyrill Gorcunov	  If unsure, say N here.
1000067bce1aSCyrill Gorcunov
10018dd2a82cSDaniel Lezcanomenuconfig NAMESPACES
10026a108a14SDavid Rientjes	bool "Namespaces support" if EXPERT
10036a108a14SDavid Rientjes	default !EXPERT
1004c5289a69SPavel Emelyanov	help
1005c5289a69SPavel Emelyanov	  Provides the way to make tasks work with different objects using
1006c5289a69SPavel Emelyanov	  the same id. For example same IPC id may refer to different objects
1007c5289a69SPavel Emelyanov	  or same user id or pid may refer to different tasks when used in
1008c5289a69SPavel Emelyanov	  different namespaces.
1009c5289a69SPavel Emelyanov
10108dd2a82cSDaniel Lezcanoif NAMESPACES
10118dd2a82cSDaniel Lezcano
101258bfdd6dSPavel Emelyanovconfig UTS_NS
101358bfdd6dSPavel Emelyanov	bool "UTS namespace"
101417a6d441SDaniel Lezcano	default y
101558bfdd6dSPavel Emelyanov	help
101658bfdd6dSPavel Emelyanov	  In this namespace tasks see different info provided with the
101758bfdd6dSPavel Emelyanov	  uname() system call
101858bfdd6dSPavel Emelyanov
1019ae5e1b22SPavel Emelyanovconfig IPC_NS
1020ae5e1b22SPavel Emelyanov	bool "IPC namespace"
10218dd2a82cSDaniel Lezcano	depends on (SYSVIPC || POSIX_MQUEUE)
102217a6d441SDaniel Lezcano	default y
1023ae5e1b22SPavel Emelyanov	help
1024ae5e1b22SPavel Emelyanov	  In this namespace tasks work with IPC ids which correspond to
1025614b84cfSSerge E. Hallyn	  different IPC objects in different namespaces.
1026ae5e1b22SPavel Emelyanov
1027aee16ce7SPavel Emelyanovconfig USER_NS
102819c92399SKees Cook	bool "User namespace"
1029e1c972b6SEric W. Biederman	depends on UIDGID_CONVERTED
10305673a94cSEric W. Biederman	select UIDGID_STRICT_TYPE_CHECKS
1031e1c972b6SEric W. Biederman
10325673a94cSEric W. Biederman	default n
1033aee16ce7SPavel Emelyanov	help
1034aee16ce7SPavel Emelyanov	  This allows containers, i.e. vservers, to use user namespaces
1035aee16ce7SPavel Emelyanov	  to provide different user info for different servers.
1036e11f0ae3SEric W. Biederman
1037e11f0ae3SEric W. Biederman	  When user namespaces are enabled in the kernel it is
1038e11f0ae3SEric W. Biederman	  recommended that the MEMCG and MEMCG_KMEM options also be
1039e11f0ae3SEric W. Biederman	  enabled and that user-space use the memory control groups to
1040e11f0ae3SEric W. Biederman	  limit the amount of memory a memory unprivileged users can
1041e11f0ae3SEric W. Biederman	  use.
1042e11f0ae3SEric W. Biederman
1043aee16ce7SPavel Emelyanov	  If unsure, say N.
1044aee16ce7SPavel Emelyanov
104574bd59bbSPavel Emelyanovconfig PID_NS
10469bd38c2cSDaniel Lezcano	bool "PID Namespaces"
104717a6d441SDaniel Lezcano	default y
104874bd59bbSPavel Emelyanov	help
104912d2b8f9SHeikki Orsila	  Support process id namespaces.  This allows having multiple
1050692105b8SMatt LaPlante	  processes with the same pid as long as they are in different
105174bd59bbSPavel Emelyanov	  pid namespaces.  This is a building block of containers.
105274bd59bbSPavel Emelyanov
1053d6eb633fSMatt Helsleyconfig NET_NS
1054d6eb633fSMatt Helsley	bool "Network namespace"
10558dd2a82cSDaniel Lezcano	depends on NET
105617a6d441SDaniel Lezcano	default y
1057d6eb633fSMatt Helsley	help
1058d6eb633fSMatt Helsley	  Allow user space to create what appear to be multiple instances
1059d6eb633fSMatt Helsley	  of the network stack.
1060d6eb633fSMatt Helsley
10618dd2a82cSDaniel Lezcanoendif # NAMESPACES
10628dd2a82cSDaniel Lezcano
1063e1c972b6SEric W. Biedermanconfig UIDGID_CONVERTED
1064e1c972b6SEric W. Biederman	# True if all of the selected software conmponents are known
1065e1c972b6SEric W. Biederman	# to have uid_t and gid_t converted to kuid_t and kgid_t
1066e1c972b6SEric W. Biederman	# where appropriate and are otherwise safe to use with
1067e1c972b6SEric W. Biederman	# the user namespace.
1068e1c972b6SEric W. Biederman	bool
1069e1c972b6SEric W. Biederman	default y
1070e1c972b6SEric W. Biederman
1071e1c972b6SEric W. Biederman	# Filesystems
1072e1c972b6SEric W. Biederman	depends on XFS_FS = n
1073e1c972b6SEric W. Biederman
10745673a94cSEric W. Biedermanconfig UIDGID_STRICT_TYPE_CHECKS
10755673a94cSEric W. Biederman	bool "Require conversions between uid/gids and their internal representation"
1076e1c972b6SEric W. Biederman	depends on UIDGID_CONVERTED
10775673a94cSEric W. Biederman	default n
10785673a94cSEric W. Biederman	help
10795673a94cSEric W. Biederman	 While the nececessary conversions are being added to all subsystems this option allows
10805673a94cSEric W. Biederman	 the code to continue to build for unconverted subsystems.
10815673a94cSEric W. Biederman
10825673a94cSEric W. Biederman	 Say Y here if you want the strict type checking enabled
10835673a94cSEric W. Biederman
10845091faa4SMike Galbraithconfig SCHED_AUTOGROUP
10855091faa4SMike Galbraith	bool "Automatic process group scheduling"
10865091faa4SMike Galbraith	select EVENTFD
10875091faa4SMike Galbraith	select CGROUPS
10885091faa4SMike Galbraith	select CGROUP_SCHED
10895091faa4SMike Galbraith	select FAIR_GROUP_SCHED
10905091faa4SMike Galbraith	help
10915091faa4SMike Galbraith	  This option optimizes the scheduler for common desktop workloads by
10925091faa4SMike Galbraith	  automatically creating and populating task groups.  This separation
10935091faa4SMike Galbraith	  of workloads isolates aggressive CPU burners (like build jobs) from
10945091faa4SMike Galbraith	  desktop applications.  Task group autogeneration is currently based
10955091faa4SMike Galbraith	  upon task session.
10965091faa4SMike Galbraith
10977af37becSDaniel Lezcanoconfig MM_OWNER
10987af37becSDaniel Lezcano	bool
10997af37becSDaniel Lezcano
11007af37becSDaniel Lezcanoconfig SYSFS_DEPRECATED
11015d6a4ea5SFerenc Wagner	bool "Enable deprecated sysfs features to support old userspace tools"
11027af37becSDaniel Lezcano	depends on SYSFS
11037af37becSDaniel Lezcano	default n
11047af37becSDaniel Lezcano	help
11057af37becSDaniel Lezcano	  This option adds code that switches the layout of the "block" class
11067af37becSDaniel Lezcano	  devices, to not show up in /sys/class/block/, but only in
11077af37becSDaniel Lezcano	  /sys/block/.
11087af37becSDaniel Lezcano
11097af37becSDaniel Lezcano	  This switch is only active when the sysfs.deprecated=1 boot option is
11107af37becSDaniel Lezcano	  passed or the SYSFS_DEPRECATED_V2 option is set.
11117af37becSDaniel Lezcano
11127af37becSDaniel Lezcano	  This option allows new kernels to run on old distributions and tools,
11137af37becSDaniel Lezcano	  which might get confused by /sys/class/block/. Since 2007/2008 all
11147af37becSDaniel Lezcano	  major distributions and tools handle this just fine.
11157af37becSDaniel Lezcano
11167af37becSDaniel Lezcano	  Recent distributions and userspace tools after 2009/2010 depend on
11177af37becSDaniel Lezcano	  the existence of /sys/class/block/, and will not work with this
11187af37becSDaniel Lezcano	  option enabled.
11197af37becSDaniel Lezcano
11207af37becSDaniel Lezcano	  Only if you are using a new kernel on an old distribution, you might
11217af37becSDaniel Lezcano	  need to say Y here.
11227af37becSDaniel Lezcano
11237af37becSDaniel Lezcanoconfig SYSFS_DEPRECATED_V2
11245d6a4ea5SFerenc Wagner	bool "Enable deprecated sysfs features by default"
11257af37becSDaniel Lezcano	default n
11267af37becSDaniel Lezcano	depends on SYSFS
11277af37becSDaniel Lezcano	depends on SYSFS_DEPRECATED
11287af37becSDaniel Lezcano	help
11297af37becSDaniel Lezcano	  Enable deprecated sysfs by default.
11307af37becSDaniel Lezcano
11317af37becSDaniel Lezcano	  See the CONFIG_SYSFS_DEPRECATED option for more details about this
11327af37becSDaniel Lezcano	  option.
11337af37becSDaniel Lezcano
11347af37becSDaniel Lezcano	  Only if you are using a new kernel on an old distribution, you might
11357af37becSDaniel Lezcano	  need to say Y here. Even then, odds are you would not need it
11367af37becSDaniel Lezcano	  enabled, you can always pass the boot option if absolutely necessary.
11377af37becSDaniel Lezcano
11387af37becSDaniel Lezcanoconfig RELAY
11397af37becSDaniel Lezcano	bool "Kernel->user space relay support (formerly relayfs)"
11407af37becSDaniel Lezcano	help
11417af37becSDaniel Lezcano	  This option enables support for relay interface support in
11427af37becSDaniel Lezcano	  certain file systems (such as debugfs).
11437af37becSDaniel Lezcano	  It is designed to provide an efficient mechanism for tools and
11447af37becSDaniel Lezcano	  facilities to relay large amounts of data from kernel space to
11457af37becSDaniel Lezcano	  user space.
11467af37becSDaniel Lezcano
11477af37becSDaniel Lezcano	  If unsure, say N.
11487af37becSDaniel Lezcano
1149f991633dSDimitri Gorokhovikconfig BLK_DEV_INITRD
1150f991633dSDimitri Gorokhovik	bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
1151f991633dSDimitri Gorokhovik	depends on BROKEN || !FRV
1152f991633dSDimitri Gorokhovik	help
1153f991633dSDimitri Gorokhovik	  The initial RAM filesystem is a ramfs which is loaded by the
1154f991633dSDimitri Gorokhovik	  boot loader (loadlin or lilo) and that is mounted as root
1155f991633dSDimitri Gorokhovik	  before the normal boot procedure. It is typically used to
1156f991633dSDimitri Gorokhovik	  load modules needed to mount the "real" root file system,
1157f991633dSDimitri Gorokhovik	  etc. See <file:Documentation/initrd.txt> for details.
1158f991633dSDimitri Gorokhovik
1159f991633dSDimitri Gorokhovik	  If RAM disk support (BLK_DEV_RAM) is also included, this
1160f991633dSDimitri Gorokhovik	  also enables initial RAM disk (initrd) support and adds
1161f991633dSDimitri Gorokhovik	  15 Kbytes (more on some other architectures) to the kernel size.
1162f991633dSDimitri Gorokhovik
1163f991633dSDimitri Gorokhovik	  If unsure say Y.
1164f991633dSDimitri Gorokhovik
1165c33df4eaSJean-Paul Samanif BLK_DEV_INITRD
1166c33df4eaSJean-Paul Saman
1167dbec4866SSam Ravnborgsource "usr/Kconfig"
1168dbec4866SSam Ravnborg
1169c33df4eaSJean-Paul Samanendif
1170c33df4eaSJean-Paul Saman
1171c45b4f1fSLinus Torvaldsconfig CC_OPTIMIZE_FOR_SIZE
117296fffeb4SIngo Molnar	bool "Optimize for size"
1173c45b4f1fSLinus Torvalds	help
1174c45b4f1fSLinus Torvalds	  Enabling this option will pass "-Os" instead of "-O2" to gcc
1175c45b4f1fSLinus Torvalds	  resulting in a smaller kernel.
1176c45b4f1fSLinus Torvalds
11773a55fb0dSKirill Smelkov	  If unsure, say N.
1178c45b4f1fSLinus Torvalds
11790847062aSRandy Dunlapconfig SYSCTL
11800847062aSRandy Dunlap	bool
11810847062aSRandy Dunlap
1182b943c460SRandy Dunlapconfig ANON_INODES
1183b943c460SRandy Dunlap	bool
1184b943c460SRandy Dunlap
11856a108a14SDavid Rientjesmenuconfig EXPERT
11866a108a14SDavid Rientjes	bool "Configure standard kernel features (expert users)"
1187f505c553SJosh Triplett	# Unhide debug options, to make the on-by-default options visible
1188f505c553SJosh Triplett	select DEBUG_KERNEL
11891da177e4SLinus Torvalds	help
11901da177e4SLinus Torvalds	  This option allows certain base kernel options and settings
11911da177e4SLinus Torvalds          to be disabled or tweaked. This is for specialized
11921da177e4SLinus Torvalds          environments which can tolerate a "non-standard" kernel.
11931da177e4SLinus Torvalds          Only use this if you really know what you are doing.
11941da177e4SLinus Torvalds
1195af1839ebSCatalin Marinasconfig HAVE_UID16
1196af1839ebSCatalin Marinas	bool
1197af1839ebSCatalin Marinas
1198ae81f9e3SChuck Ebbertconfig UID16
11996a108a14SDavid Rientjes	bool "Enable 16-bit UID system calls" if EXPERT
1200af1839ebSCatalin Marinas	depends on HAVE_UID16
1201ae81f9e3SChuck Ebbert	default y
1202ae81f9e3SChuck Ebbert	help
1203ae81f9e3SChuck Ebbert	  This enables the legacy 16-bit UID syscall wrappers.
1204ae81f9e3SChuck Ebbert
1205b89a8171SEric W. Biedermanconfig SYSCTL_SYSCALL
12066a108a14SDavid Rientjes	bool "Sysctl syscall support" if EXPERT
120726a7034bSEric W. Biederman	depends on PROC_SYSCTL
1208c736de60SWANG Cong	default n
1209b89a8171SEric W. Biederman	select SYSCTL
1210b89a8171SEric W. Biederman	---help---
121113bb7e37SEric W. Biederman	  sys_sysctl uses binary paths that have been found challenging
121213bb7e37SEric W. Biederman	  to properly maintain and use.  The interface in /proc/sys
121313bb7e37SEric W. Biederman	  using paths with ascii names is now the primary path to this
121413bb7e37SEric W. Biederman	  information.
1215b89a8171SEric W. Biederman
121613bb7e37SEric W. Biederman	  Almost nothing using the binary sysctl interface so if you are
121713bb7e37SEric W. Biederman	  trying to save some space it is probably safe to disable this,
121813bb7e37SEric W. Biederman	  making your kernel marginally smaller.
1219b89a8171SEric W. Biederman
1220c736de60SWANG Cong	  If unsure say N here.
1221ae81f9e3SChuck Ebbert
12227ac57a89SCatalin Marinasconfig SYSCTL_EXCEPTION_TRACE
12237ac57a89SCatalin Marinas	bool
12247ac57a89SCatalin Marinas	help
12257ac57a89SCatalin Marinas	  Enable support for /proc/sys/debug/exception-trace.
12267ac57a89SCatalin Marinas
1227b6fca725SVineet Guptaconfig SYSCTL_ARCH_UNALIGN_NO_WARN
1228b6fca725SVineet Gupta	bool
1229b6fca725SVineet Gupta	help
1230b6fca725SVineet Gupta	  Enable support for /proc/sys/kernel/ignore-unaligned-usertrap
1231b6fca725SVineet Gupta	  Allows arch to define/use @no_unaligned_warning to possibly warn
1232b6fca725SVineet Gupta	  about unaligned access emulation going on under the hood.
1233b6fca725SVineet Gupta
1234bf14e3b9SVineet Guptaconfig SYSCTL_ARCH_UNALIGN_ALLOW
1235bf14e3b9SVineet Gupta	bool
1236bf14e3b9SVineet Gupta	help
1237bf14e3b9SVineet Gupta	  Enable support for /proc/sys/kernel/unaligned-trap
1238bf14e3b9SVineet Gupta	  Allows arches to define/use @unaligned_enabled to runtime toggle
1239bf14e3b9SVineet Gupta	  the unaligned access emulation.
1240bf14e3b9SVineet Gupta	  see arch/parisc/kernel/unaligned.c for reference
1241bf14e3b9SVineet Gupta
12421da177e4SLinus Torvaldsconfig KALLSYMS
12436a108a14SDavid Rientjes	 bool "Load all symbols for debugging/ksymoops" if EXPERT
12441da177e4SLinus Torvalds	 default y
12451da177e4SLinus Torvalds	 help
12461da177e4SLinus Torvalds	   Say Y here to let the kernel print out symbolic crash information and
12471da177e4SLinus Torvalds	   symbolic stack backtraces. This increases the size of the kernel
12481da177e4SLinus Torvalds	   somewhat, as all symbols have to be loaded into the kernel image.
12491da177e4SLinus Torvalds
12501da177e4SLinus Torvaldsconfig KALLSYMS_ALL
12511da177e4SLinus Torvalds	bool "Include all symbols in kallsyms"
12521da177e4SLinus Torvalds	depends on DEBUG_KERNEL && KALLSYMS
12531da177e4SLinus Torvalds	help
125471a83ec7SArtem Bityutskiy	   Normally kallsyms only contains the symbols of functions for nicer
125571a83ec7SArtem Bityutskiy	   OOPS messages and backtraces (i.e., symbols from the text and inittext
125671a83ec7SArtem Bityutskiy	   sections). This is sufficient for most cases. And only in very rare
125771a83ec7SArtem Bityutskiy	   cases (e.g., when a debugger is used) all symbols are required (e.g.,
125871a83ec7SArtem Bityutskiy	   names of variables from the data sections, etc).
12591da177e4SLinus Torvalds
126071a83ec7SArtem Bityutskiy	   This option makes sure that all symbols are loaded into the kernel
126171a83ec7SArtem Bityutskiy	   image (i.e., symbols from all sections) in cost of increased kernel
126271a83ec7SArtem Bityutskiy	   size (depending on the kernel configuration, it may be 300KiB or
126371a83ec7SArtem Bityutskiy	   something like this).
12641da177e4SLinus Torvalds
126571a83ec7SArtem Bityutskiy	   Say N unless you really need all symbols.
1266d59745ceSMatt Mackall
1267712f47ceSGreg Kroah-Hartmanconfig HOTPLUG
126845f035abSGreg Kroah-Hartman	def_bool y
1269712f47ceSGreg Kroah-Hartman
1270d59745ceSMatt Mackallconfig PRINTK
1271d59745ceSMatt Mackall	default y
12726a108a14SDavid Rientjes	bool "Enable support for printk" if EXPERT
127374876a98SFrederic Weisbecker	select IRQ_WORK
1274d59745ceSMatt Mackall	help
1275d59745ceSMatt Mackall	  This option enables normal printk support. Removing it
1276d59745ceSMatt Mackall	  eliminates most of the message strings from the kernel image
1277d59745ceSMatt Mackall	  and makes the kernel more or less silent. As this makes it
1278d59745ceSMatt Mackall	  very difficult to diagnose system problems, saying N here is
1279d59745ceSMatt Mackall	  strongly discouraged.
1280d59745ceSMatt Mackall
1281c8538a7aSMatt Mackallconfig BUG
12826a108a14SDavid Rientjes	bool "BUG() support" if EXPERT
1283c8538a7aSMatt Mackall	default y
1284c8538a7aSMatt Mackall	help
1285c8538a7aSMatt Mackall          Disabling this option eliminates support for BUG and WARN, reducing
1286c8538a7aSMatt Mackall          the size of your kernel image and potentially quietly ignoring
1287c8538a7aSMatt Mackall          numerous fatal conditions. You should only consider disabling this
1288c8538a7aSMatt Mackall          option for embedded systems with no facilities for reporting errors.
1289c8538a7aSMatt Mackall          Just say Y.
1290c8538a7aSMatt Mackall
1291708e9a79SMatt Mackallconfig ELF_CORE
1292046d662fSAlex Kelly	depends on COREDUMP
1293708e9a79SMatt Mackall	default y
12946a108a14SDavid Rientjes	bool "Enable ELF core dumps" if EXPERT
1295708e9a79SMatt Mackall	help
1296708e9a79SMatt Mackall	  Enable support for generating core dumps. Disabling saves about 4k.
1297708e9a79SMatt Mackall
12988761f1abSRalf Baechle
1299e5e1d3cbSStas Sergeevconfig PCSPKR_PLATFORM
13006a108a14SDavid Rientjes	bool "Enable PC-Speaker support" if EXPERT
13018761f1abSRalf Baechle	depends on HAVE_PCSPKR_PLATFORM
130215f304b6SRalf Baechle	select I8253_LOCK
1303e5e1d3cbSStas Sergeev	default y
1304e5e1d3cbSStas Sergeev	help
1305e5e1d3cbSStas Sergeev          This option allows to disable the internal PC-Speaker
1306e5e1d3cbSStas Sergeev          support, saving some memory.
1307e5e1d3cbSStas Sergeev
13088761f1abSRalf Baechleconfig HAVE_PCSPKR_PLATFORM
13098761f1abSRalf Baechle	bool
13108761f1abSRalf Baechle
13111da177e4SLinus Torvaldsconfig BASE_FULL
13121da177e4SLinus Torvalds	default y
13136a108a14SDavid Rientjes	bool "Enable full-sized data structures for core" if EXPERT
13141da177e4SLinus Torvalds	help
13151da177e4SLinus Torvalds	  Disabling this option reduces the size of miscellaneous core
13161da177e4SLinus Torvalds	  kernel data structures. This saves memory on small machines,
13171da177e4SLinus Torvalds	  but may reduce performance.
13181da177e4SLinus Torvalds
13191da177e4SLinus Torvaldsconfig FUTEX
13206a108a14SDavid Rientjes	bool "Enable futex support" if EXPERT
13211da177e4SLinus Torvalds	default y
132223f78d4aSIngo Molnar	select RT_MUTEXES
13231da177e4SLinus Torvalds	help
13241da177e4SLinus Torvalds	  Disabling this option will cause the kernel to be built without
13251da177e4SLinus Torvalds	  support for "fast userspace mutexes".  The resulting kernel may not
13261da177e4SLinus Torvalds	  run glibc-based applications correctly.
13271da177e4SLinus Torvalds
13281da177e4SLinus Torvaldsconfig EPOLL
13296a108a14SDavid Rientjes	bool "Enable eventpoll support" if EXPERT
13301da177e4SLinus Torvalds	default y
1331448e3ceeSAdrian Bunk	select ANON_INODES
13321da177e4SLinus Torvalds	help
13331da177e4SLinus Torvalds	  Disabling this option will cause the kernel to be built without
13341da177e4SLinus Torvalds	  support for epoll family of system calls.
13351da177e4SLinus Torvalds
1336fba2afaaSDavide Libenziconfig SIGNALFD
13376a108a14SDavid Rientjes	bool "Enable signalfd() system call" if EXPERT
1338448e3ceeSAdrian Bunk	select ANON_INODES
1339fba2afaaSDavide Libenzi	default y
1340fba2afaaSDavide Libenzi	help
1341fba2afaaSDavide Libenzi	  Enable the signalfd() system call that allows to receive signals
1342fba2afaaSDavide Libenzi	  on a file descriptor.
1343fba2afaaSDavide Libenzi
1344fba2afaaSDavide Libenzi	  If unsure, say Y.
1345fba2afaaSDavide Libenzi
1346b215e283SDavide Libenziconfig TIMERFD
13476a108a14SDavid Rientjes	bool "Enable timerfd() system call" if EXPERT
1348448e3ceeSAdrian Bunk	select ANON_INODES
1349b215e283SDavide Libenzi	default y
1350b215e283SDavide Libenzi	help
1351b215e283SDavide Libenzi	  Enable the timerfd() system call that allows to receive timer
1352b215e283SDavide Libenzi	  events on a file descriptor.
1353b215e283SDavide Libenzi
1354b215e283SDavide Libenzi	  If unsure, say Y.
1355b215e283SDavide Libenzi
1356e1ad7468SDavide Libenziconfig EVENTFD
13576a108a14SDavid Rientjes	bool "Enable eventfd() system call" if EXPERT
1358448e3ceeSAdrian Bunk	select ANON_INODES
1359e1ad7468SDavide Libenzi	default y
1360e1ad7468SDavide Libenzi	help
1361e1ad7468SDavide Libenzi	  Enable the eventfd() system call that allows to receive both
1362e1ad7468SDavide Libenzi	  kernel notification (ie. KAIO) or userspace notifications.
1363e1ad7468SDavide Libenzi
1364e1ad7468SDavide Libenzi	  If unsure, say Y.
1365e1ad7468SDavide Libenzi
13661da177e4SLinus Torvaldsconfig SHMEM
13676a108a14SDavid Rientjes	bool "Use full shmem filesystem" if EXPERT
13681da177e4SLinus Torvalds	default y
13691da177e4SLinus Torvalds	depends on MMU
13701da177e4SLinus Torvalds	help
13711da177e4SLinus Torvalds	  The shmem is an internal filesystem used to manage shared memory.
13721da177e4SLinus Torvalds	  It is backed by swap and manages resource limits. It is also exported
13731da177e4SLinus Torvalds	  to userspace as tmpfs if TMPFS is enabled. Disabling this
13741da177e4SLinus Torvalds	  option replaces shmem and tmpfs with the much simpler ramfs code,
13751da177e4SLinus Torvalds	  which may be appropriate on small systems without swap.
13761da177e4SLinus Torvalds
1377ebf3f09cSThomas Petazzoniconfig AIO
13786a108a14SDavid Rientjes	bool "Enable AIO support" if EXPERT
1379ebf3f09cSThomas Petazzoni	default y
1380ebf3f09cSThomas Petazzoni	help
1381ebf3f09cSThomas Petazzoni	  This option enables POSIX asynchronous I/O which may by used
1382ebf3f09cSThomas Petazzoni          by some high performance threaded applications. Disabling
1383ebf3f09cSThomas Petazzoni          this option saves about 7k.
1384ebf3f09cSThomas Petazzoni
13856befe5f6SRandy Dunlapconfig EMBEDDED
13866befe5f6SRandy Dunlap	bool "Embedded system"
13876befe5f6SRandy Dunlap	select EXPERT
13886befe5f6SRandy Dunlap	help
13896befe5f6SRandy Dunlap	  This option should be enabled if compiling the kernel for
13906befe5f6SRandy Dunlap	  an embedded system so certain expert options are available
13916befe5f6SRandy Dunlap	  for configuration.
13926befe5f6SRandy Dunlap
1393cdd6c482SIngo Molnarconfig HAVE_PERF_EVENTS
13940793a61dSThomas Gleixner	bool
1395018df72dSMike Frysinger	help
1396018df72dSMike Frysinger	  See tools/perf/design.txt for details.
13970793a61dSThomas Gleixner
1398906010b2SPeter Zijlstraconfig PERF_USE_VMALLOC
1399906010b2SPeter Zijlstra	bool
1400906010b2SPeter Zijlstra	help
1401906010b2SPeter Zijlstra	  See tools/perf/design.txt for details
1402906010b2SPeter Zijlstra
140357c0c15bSIngo Molnarmenu "Kernel Performance Events And Counters"
14040793a61dSThomas Gleixner
1405cdd6c482SIngo Molnarconfig PERF_EVENTS
140657c0c15bSIngo Molnar	bool "Kernel performance events and counters"
1407392d65a9SRobert Richter	default y if PROFILING
1408cdd6c482SIngo Molnar	depends on HAVE_PERF_EVENTS
14094c59e467SIngo Molnar	select ANON_INODES
1410e360adbeSPeter Zijlstra	select IRQ_WORK
14110793a61dSThomas Gleixner	help
141257c0c15bSIngo Molnar	  Enable kernel support for various performance events provided
141357c0c15bSIngo Molnar	  by software and hardware.
14140793a61dSThomas Gleixner
1415dd77038dSThadeu Lima de Souza Cascardo	  Software events are supported either built-in or via the
141657c0c15bSIngo Molnar	  use of generic tracepoints.
141757c0c15bSIngo Molnar
141857c0c15bSIngo Molnar	  Most modern CPUs support performance events via performance
141957c0c15bSIngo Molnar	  counter registers. These registers count the number of certain
14200793a61dSThomas Gleixner	  types of hw events: such as instructions executed, cachemisses
14210793a61dSThomas Gleixner	  suffered, or branches mis-predicted - without slowing down the
14220793a61dSThomas Gleixner	  kernel or applications. These registers can also trigger interrupts
14230793a61dSThomas Gleixner	  when a threshold number of events have passed - and can thus be
14240793a61dSThomas Gleixner	  used to profile the code that runs on that CPU.
14250793a61dSThomas Gleixner
142657c0c15bSIngo Molnar	  The Linux Performance Event subsystem provides an abstraction of
1427dd77038dSThadeu Lima de Souza Cascardo	  these software and hardware event capabilities, available via a
142857c0c15bSIngo Molnar	  system call and used by the "perf" utility in tools/perf/. It
14290793a61dSThomas Gleixner	  provides per task and per CPU counters, and it provides event
14300793a61dSThomas Gleixner	  capabilities on top of those.
14310793a61dSThomas Gleixner
14320793a61dSThomas Gleixner	  Say Y if unsure.
14330793a61dSThomas Gleixner
1434906010b2SPeter Zijlstraconfig DEBUG_PERF_USE_VMALLOC
1435906010b2SPeter Zijlstra	default n
1436906010b2SPeter Zijlstra	bool "Debug: use vmalloc to back perf mmap() buffers"
1437906010b2SPeter Zijlstra	depends on PERF_EVENTS && DEBUG_KERNEL
1438906010b2SPeter Zijlstra	select PERF_USE_VMALLOC
1439906010b2SPeter Zijlstra	help
1440906010b2SPeter Zijlstra	 Use vmalloc memory to back perf mmap() buffers.
1441906010b2SPeter Zijlstra
1442906010b2SPeter Zijlstra	 Mostly useful for debugging the vmalloc code on platforms
1443906010b2SPeter Zijlstra	 that don't require it.
1444906010b2SPeter Zijlstra
1445906010b2SPeter Zijlstra	 Say N if unsure.
1446906010b2SPeter Zijlstra
14470793a61dSThomas Gleixnerendmenu
14480793a61dSThomas Gleixner
1449f8891e5eSChristoph Lameterconfig VM_EVENT_COUNTERS
1450f8891e5eSChristoph Lameter	default y
14516a108a14SDavid Rientjes	bool "Enable VM event counters for /proc/vmstat" if EXPERT
1452f8891e5eSChristoph Lameter	help
14532aea4fb6SPaul Jackson	  VM event counters are needed for event counts to be shown.
14542aea4fb6SPaul Jackson	  This option allows the disabling of the VM event counters
14556a108a14SDavid Rientjes	  on EXPERT systems.  /proc/vmstat will only show page counts
14562aea4fb6SPaul Jackson	  if VM event counters are disabled.
1457f8891e5eSChristoph Lameter
14583d137310SThomas Petazzoniconfig PCI_QUIRKS
14593d137310SThomas Petazzoni	default y
14606a108a14SDavid Rientjes	bool "Enable PCI quirk workarounds" if EXPERT
146161cfc7e4SGeert Uytterhoeven	depends on PCI
14623d137310SThomas Petazzoni	help
14633d137310SThomas Petazzoni	  This enables workarounds for various PCI chipset
14643d137310SThomas Petazzoni          bugs/quirks. Disable this only if your target machine is
14653d137310SThomas Petazzoni          unaffected by PCI quirks.
14663d137310SThomas Petazzoni
146741ecc55bSChristoph Lameterconfig SLUB_DEBUG
146841ecc55bSChristoph Lameter	default y
14696a108a14SDavid Rientjes	bool "Enable SLUB debugging support" if EXPERT
1470f6acb635SChristoph Lameter	depends on SLUB && SYSFS
147141ecc55bSChristoph Lameter	help
147241ecc55bSChristoph Lameter	  SLUB has extensive debug support features. Disabling these can
147341ecc55bSChristoph Lameter	  result in significant savings in code size. This also disables
147441ecc55bSChristoph Lameter	  SLUB sysfs support. /sys/slab will not exist and there will be
147541ecc55bSChristoph Lameter	  no support for cache validation etc.
147641ecc55bSChristoph Lameter
1477b943c460SRandy Dunlapconfig COMPAT_BRK
1478b943c460SRandy Dunlap	bool "Disable heap randomization"
1479b943c460SRandy Dunlap	default y
1480b943c460SRandy Dunlap	help
1481b943c460SRandy Dunlap	  Randomizing heap placement makes heap exploits harder, but it
1482b943c460SRandy Dunlap	  also breaks ancient binaries (including anything libc5 based).
1483b943c460SRandy Dunlap	  This option changes the bootup default to heap randomization
1484692105b8SMatt LaPlante	  disabled, and can be overridden at runtime by setting
1485b943c460SRandy Dunlap	  /proc/sys/kernel/randomize_va_space to 2.
1486b943c460SRandy Dunlap
1487b943c460SRandy Dunlap	  On non-ancient distros (post-2000 ones) N is usually a safe choice.
1488b943c460SRandy Dunlap
148981819f0fSChristoph Lameterchoice
149081819f0fSChristoph Lameter	prompt "Choose SLAB allocator"
1491a0acd820SChristoph Lameter	default SLUB
149281819f0fSChristoph Lameter	help
149381819f0fSChristoph Lameter	   This option allows to select a slab allocator.
149481819f0fSChristoph Lameter
149581819f0fSChristoph Lameterconfig SLAB
149681819f0fSChristoph Lameter	bool "SLAB"
149781819f0fSChristoph Lameter	help
149881819f0fSChristoph Lameter	  The regular slab allocator that is established and known to work
149934013886SChristoph Lameter	  well in all environments. It organizes cache hot objects in
150002f56210SSimon Arlott	  per cpu and per node queues.
150181819f0fSChristoph Lameter
150281819f0fSChristoph Lameterconfig SLUB
150381819f0fSChristoph Lameter	bool "SLUB (Unqueued Allocator)"
150481819f0fSChristoph Lameter	help
150581819f0fSChristoph Lameter	   SLUB is a slab allocator that minimizes cache line usage
150681819f0fSChristoph Lameter	   instead of managing queues of cached objects (SLAB approach).
150781819f0fSChristoph Lameter	   Per cpu caching is realized using slabs of objects instead
150881819f0fSChristoph Lameter	   of queues of objects. SLUB can use memory efficiently
150902f56210SSimon Arlott	   and has enhanced diagnostics. SLUB is the default choice for
151002f56210SSimon Arlott	   a slab allocator.
151181819f0fSChristoph Lameter
151281819f0fSChristoph Lameterconfig SLOB
15136a108a14SDavid Rientjes	depends on EXPERT
151481819f0fSChristoph Lameter	bool "SLOB (Simple Allocator)"
151581819f0fSChristoph Lameter	help
151637291458SMatt Mackall	   SLOB replaces the stock allocator with a drastically simpler
151737291458SMatt Mackall	   allocator. SLOB is generally more space efficient but
151837291458SMatt Mackall	   does not perform as well on large systems.
151981819f0fSChristoph Lameter
152081819f0fSChristoph Lameterendchoice
152181819f0fSChristoph Lameter
1522ea637639SJie Zhangconfig MMAP_ALLOW_UNINITIALIZED
1523ea637639SJie Zhang	bool "Allow mmapped anonymous memory to be uninitialized"
15246a108a14SDavid Rientjes	depends on EXPERT && !MMU
1525ea637639SJie Zhang	default n
1526ea637639SJie Zhang	help
1527ea637639SJie Zhang	  Normally, and according to the Linux spec, anonymous memory obtained
1528ea637639SJie Zhang	  from mmap() has it's contents cleared before it is passed to
1529ea637639SJie Zhang	  userspace.  Enabling this config option allows you to request that
1530ea637639SJie Zhang	  mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus
1531ea637639SJie Zhang	  providing a huge performance boost.  If this option is not enabled,
1532ea637639SJie Zhang	  then the flag will be ignored.
1533ea637639SJie Zhang
1534ea637639SJie Zhang	  This is taken advantage of by uClibc's malloc(), and also by
1535ea637639SJie Zhang	  ELF-FDPIC binfmt's brk and stack allocator.
1536ea637639SJie Zhang
1537ea637639SJie Zhang	  Because of the obvious security issues, this option should only be
1538ea637639SJie Zhang	  enabled on embedded devices where you control what is run in
1539ea637639SJie Zhang	  userspace.  Since that isn't generally a problem on no-MMU systems,
1540ea637639SJie Zhang	  it is normally safe to say Y here.
1541ea637639SJie Zhang
1542ea637639SJie Zhang	  See Documentation/nommu-mmap.txt for more information.
1543ea637639SJie Zhang
1544125e5645SMathieu Desnoyersconfig PROFILING
1545b309a294SRobert Richter	bool "Profiling support"
1546125e5645SMathieu Desnoyers	help
1547125e5645SMathieu Desnoyers	  Say Y here to enable the extended profiling support mechanisms used
1548125e5645SMathieu Desnoyers	  by profilers such as OProfile.
1549125e5645SMathieu Desnoyers
15505f87f112SIngo Molnar#
15515f87f112SIngo Molnar# Place an empty function call at each tracepoint site. Can be
15525f87f112SIngo Molnar# dynamically changed for a probe function.
15535f87f112SIngo Molnar#
155497e1c18eSMathieu Desnoyersconfig TRACEPOINTS
15555f87f112SIngo Molnar	bool
155697e1c18eSMathieu Desnoyers
1557fb32e03fSMathieu Desnoyerssource "arch/Kconfig"
1558fb32e03fSMathieu Desnoyers
15591da177e4SLinus Torvaldsendmenu		# General setup
15601da177e4SLinus Torvalds
1561ee7e5516SDmitry Baryshkovconfig HAVE_GENERIC_DMA_COHERENT
1562ee7e5516SDmitry Baryshkov	bool
1563ee7e5516SDmitry Baryshkov	default n
1564ee7e5516SDmitry Baryshkov
1565158a9624SLinus Torvaldsconfig SLABINFO
1566158a9624SLinus Torvalds	bool
1567158a9624SLinus Torvalds	depends on PROC_FS
15680f389ec6SChristoph Lameter	depends on SLAB || SLUB_DEBUG
1569158a9624SLinus Torvalds	default y
1570158a9624SLinus Torvalds
1571ae81f9e3SChuck Ebbertconfig RT_MUTEXES
1572ae81f9e3SChuck Ebbert	boolean
1573ae81f9e3SChuck Ebbert
15741da177e4SLinus Torvaldsconfig BASE_SMALL
15751da177e4SLinus Torvalds	int
15761da177e4SLinus Torvalds	default 0 if BASE_FULL
15771da177e4SLinus Torvalds	default 1 if !BASE_FULL
15781da177e4SLinus Torvalds
157966da5733SJan Engelhardtmenuconfig MODULES
15801da177e4SLinus Torvalds	bool "Enable loadable module support"
15811da177e4SLinus Torvalds	help
15821da177e4SLinus Torvalds	  Kernel modules are small pieces of compiled code which can
15831da177e4SLinus Torvalds	  be inserted in the running kernel, rather than being
15841da177e4SLinus Torvalds	  permanently built into the kernel.  You use the "modprobe"
15851da177e4SLinus Torvalds	  tool to add (and sometimes remove) them.  If you say Y here,
15861da177e4SLinus Torvalds	  many parts of the kernel can be built as modules (by
15871da177e4SLinus Torvalds	  answering M instead of Y where indicated): this is most
15881da177e4SLinus Torvalds	  useful for infrequently used options which are not required
15891da177e4SLinus Torvalds	  for booting.  For more information, see the man pages for
15901da177e4SLinus Torvalds	  modprobe, lsmod, modinfo, insmod and rmmod.
15911da177e4SLinus Torvalds
15921da177e4SLinus Torvalds	  If you say Y here, you will need to run "make
15931da177e4SLinus Torvalds	  modules_install" to put the modules under /lib/modules/
15941da177e4SLinus Torvalds	  where modprobe can find them (you may need to be root to do
15951da177e4SLinus Torvalds	  this).
15961da177e4SLinus Torvalds
15971da177e4SLinus Torvalds	  If unsure, say Y.
15981da177e4SLinus Torvalds
15990b0de144SRobert P. J. Dayif MODULES
16000b0de144SRobert P. J. Day
1601826e4506SLinus Torvaldsconfig MODULE_FORCE_LOAD
1602826e4506SLinus Torvalds	bool "Forced module loading"
1603826e4506SLinus Torvalds	default n
1604826e4506SLinus Torvalds	help
160591e37a79SRusty Russell	  Allow loading of modules without version information (ie. modprobe
160691e37a79SRusty Russell	  --force).  Forced module loading sets the 'F' (forced) taint flag and
160791e37a79SRusty Russell	  is usually a really bad idea.
1608826e4506SLinus Torvalds
16091da177e4SLinus Torvaldsconfig MODULE_UNLOAD
16101da177e4SLinus Torvalds	bool "Module unloading"
16111da177e4SLinus Torvalds	help
16121da177e4SLinus Torvalds	  Without this option you will not be able to unload any
16131da177e4SLinus Torvalds	  modules (note that some modules may not be unloadable
1614f7f5b675SDenys Vlasenko	  anyway), which makes your kernel smaller, faster
1615f7f5b675SDenys Vlasenko	  and simpler.  If unsure, say Y.
16161da177e4SLinus Torvalds
16171da177e4SLinus Torvaldsconfig MODULE_FORCE_UNLOAD
16181da177e4SLinus Torvalds	bool "Forced module unloading"
161919c92399SKees Cook	depends on MODULE_UNLOAD
16201da177e4SLinus Torvalds	help
16211da177e4SLinus Torvalds	  This option allows you to force a module to unload, even if the
16221da177e4SLinus Torvalds	  kernel believes it is unsafe: the kernel will remove the module
16231da177e4SLinus Torvalds	  without waiting for anyone to stop using it (using the -f option to
16241da177e4SLinus Torvalds	  rmmod).  This is mainly for kernel developers and desperate users.
16251da177e4SLinus Torvalds	  If unsure, say N.
16261da177e4SLinus Torvalds
16271da177e4SLinus Torvaldsconfig MODVERSIONS
16280d541643SSam Ravnborg	bool "Module versioning support"
16291da177e4SLinus Torvalds	help
16301da177e4SLinus Torvalds	  Usually, you have to use modules compiled with your kernel.
16311da177e4SLinus Torvalds	  Saying Y here makes it sometimes possible to use modules
16321da177e4SLinus Torvalds	  compiled for different kernels, by adding enough information
16331da177e4SLinus Torvalds	  to the modules to (hopefully) spot any changes which would
16341da177e4SLinus Torvalds	  make them incompatible with the kernel you are running.  If
16351da177e4SLinus Torvalds	  unsure, say N.
16361da177e4SLinus Torvalds
16371da177e4SLinus Torvaldsconfig MODULE_SRCVERSION_ALL
16381da177e4SLinus Torvalds	bool "Source checksum for all modules"
16391da177e4SLinus Torvalds	help
16401da177e4SLinus Torvalds	  Modules which contain a MODULE_VERSION get an extra "srcversion"
16411da177e4SLinus Torvalds	  field inserted into their modinfo section, which contains a
16421da177e4SLinus Torvalds    	  sum of the source files which made it.  This helps maintainers
16431da177e4SLinus Torvalds	  see exactly which source was used to build a module (since
16441da177e4SLinus Torvalds	  others sometimes change the module source without updating
16451da177e4SLinus Torvalds	  the version).  With this option, such a "srcversion" field
16461da177e4SLinus Torvalds	  will be created for all modules.  If unsure, say N.
16471da177e4SLinus Torvalds
1648106a4ee2SRusty Russellconfig MODULE_SIG
1649106a4ee2SRusty Russell	bool "Module signature verification"
1650106a4ee2SRusty Russell	depends on MODULES
165148ba2462SDavid Howells	select KEYS
165248ba2462SDavid Howells	select CRYPTO
165348ba2462SDavid Howells	select ASYMMETRIC_KEY_TYPE
165448ba2462SDavid Howells	select ASYMMETRIC_PUBLIC_KEY_SUBTYPE
165548ba2462SDavid Howells	select PUBLIC_KEY_ALGO_RSA
165648ba2462SDavid Howells	select ASN1
165748ba2462SDavid Howells	select OID_REGISTRY
165848ba2462SDavid Howells	select X509_CERTIFICATE_PARSER
1659106a4ee2SRusty Russell	help
1660106a4ee2SRusty Russell	  Check modules for valid signatures upon load: the signature
1661106a4ee2SRusty Russell	  is simply appended to the module. For more information see
1662106a4ee2SRusty Russell	  Documentation/module-signing.txt.
1663106a4ee2SRusty Russell
1664ea0b6dcfSDavid Howells	  !!!WARNING!!!  If you enable this option, you MUST make sure that the
1665ea0b6dcfSDavid Howells	  module DOES NOT get stripped after being signed.  This includes the
1666ea0b6dcfSDavid Howells	  debuginfo strip done by some packagers (such as rpmbuild) and
1667ea0b6dcfSDavid Howells	  inclusion into an initramfs that wants the module size reduced.
1668ea0b6dcfSDavid Howells
1669106a4ee2SRusty Russellconfig MODULE_SIG_FORCE
1670106a4ee2SRusty Russell	bool "Require modules to be validly signed"
1671106a4ee2SRusty Russell	depends on MODULE_SIG
1672106a4ee2SRusty Russell	help
1673106a4ee2SRusty Russell	  Reject unsigned modules or signed modules for which we don't have a
1674106a4ee2SRusty Russell	  key.  Without this, such modules will simply taint the kernel.
1675ea0b6dcfSDavid Howells
1676d9d8d7edSMichal Marekconfig MODULE_SIG_ALL
1677d9d8d7edSMichal Marek	bool "Automatically sign all modules"
1678d9d8d7edSMichal Marek	default y
1679d9d8d7edSMichal Marek	depends on MODULE_SIG
1680d9d8d7edSMichal Marek	help
1681d9d8d7edSMichal Marek	  Sign all modules during make modules_install. Without this option,
1682d9d8d7edSMichal Marek	  modules must be signed manually, using the scripts/sign-file tool.
1683d9d8d7edSMichal Marek
1684d9d8d7edSMichal Marekcomment "Do not forget to sign required modules with scripts/sign-file"
1685d9d8d7edSMichal Marek	depends on MODULE_SIG_FORCE && !MODULE_SIG_ALL
1686d9d8d7edSMichal Marek
1687ea0b6dcfSDavid Howellschoice
1688ea0b6dcfSDavid Howells	prompt "Which hash algorithm should modules be signed with?"
1689ea0b6dcfSDavid Howells	depends on MODULE_SIG
1690ea0b6dcfSDavid Howells	help
1691ea0b6dcfSDavid Howells	  This determines which sort of hashing algorithm will be used during
1692ea0b6dcfSDavid Howells	  signature generation.  This algorithm _must_ be built into the kernel
1693ea0b6dcfSDavid Howells	  directly so that signature verification can take place.  It is not
1694ea0b6dcfSDavid Howells	  possible to load a signed module containing the algorithm to check
1695ea0b6dcfSDavid Howells	  the signature on that module.
1696ea0b6dcfSDavid Howells
1697ea0b6dcfSDavid Howellsconfig MODULE_SIG_SHA1
1698ea0b6dcfSDavid Howells	bool "Sign modules with SHA-1"
1699ea0b6dcfSDavid Howells	select CRYPTO_SHA1
1700ea0b6dcfSDavid Howells
1701ea0b6dcfSDavid Howellsconfig MODULE_SIG_SHA224
1702ea0b6dcfSDavid Howells	bool "Sign modules with SHA-224"
1703ea0b6dcfSDavid Howells	select CRYPTO_SHA256
1704ea0b6dcfSDavid Howells
1705ea0b6dcfSDavid Howellsconfig MODULE_SIG_SHA256
1706ea0b6dcfSDavid Howells	bool "Sign modules with SHA-256"
1707ea0b6dcfSDavid Howells	select CRYPTO_SHA256
1708ea0b6dcfSDavid Howells
1709ea0b6dcfSDavid Howellsconfig MODULE_SIG_SHA384
1710ea0b6dcfSDavid Howells	bool "Sign modules with SHA-384"
1711ea0b6dcfSDavid Howells	select CRYPTO_SHA512
1712ea0b6dcfSDavid Howells
1713ea0b6dcfSDavid Howellsconfig MODULE_SIG_SHA512
1714ea0b6dcfSDavid Howells	bool "Sign modules with SHA-512"
1715ea0b6dcfSDavid Howells	select CRYPTO_SHA512
1716ea0b6dcfSDavid Howells
1717ea0b6dcfSDavid Howellsendchoice
1718ea0b6dcfSDavid Howells
171922753674SMichal Marekconfig MODULE_SIG_HASH
172022753674SMichal Marek	string
172122753674SMichal Marek	depends on MODULE_SIG
172222753674SMichal Marek	default "sha1" if MODULE_SIG_SHA1
172322753674SMichal Marek	default "sha224" if MODULE_SIG_SHA224
172422753674SMichal Marek	default "sha256" if MODULE_SIG_SHA256
172522753674SMichal Marek	default "sha384" if MODULE_SIG_SHA384
172622753674SMichal Marek	default "sha512" if MODULE_SIG_SHA512
172722753674SMichal Marek
17280b0de144SRobert P. J. Dayendif # MODULES
17290b0de144SRobert P. J. Day
173098a79d6aSRusty Russellconfig INIT_ALL_POSSIBLE
173198a79d6aSRusty Russell	bool
173298a79d6aSRusty Russell	help
17335f054e31SRusty Russell	  Back when each arch used to define their own cpu_online_mask and
17345f054e31SRusty Russell	  cpu_possible_mask, some of them chose to initialize cpu_possible_mask
173598a79d6aSRusty Russell	  with all 1s, and others with all 0s.  When they were centralised,
173698a79d6aSRusty Russell	  it was better to provide this option than to break all the archs
1737692105b8SMatt LaPlante	  and have several arch maintainers pursuing me down dark alleys.
173898a79d6aSRusty Russell
17391da177e4SLinus Torvaldsconfig STOP_MACHINE
17401da177e4SLinus Torvalds	bool
17411da177e4SLinus Torvalds	default y
17421da177e4SLinus Torvalds	depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
17431da177e4SLinus Torvalds	help
17441da177e4SLinus Torvalds	  Need stop_machine() primitive.
17453a65dfe8SJens Axboe
17463a65dfe8SJens Axboesource "block/Kconfig"
1747e98c3202SAvi Kivity
1748e98c3202SAvi Kivityconfig PREEMPT_NOTIFIERS
1749e98c3202SAvi Kivity	bool
1750e260be67SPaul E. McKenney
175116295becSSteffen Klassertconfig PADATA
175216295becSSteffen Klassert	depends on SMP
175316295becSSteffen Klassert	bool
175416295becSSteffen Klassert
1755754b7b63SAndi Kleen# Can be selected by architectures with broken toolchains
1756754b7b63SAndi Kleen# that get confused by correct const<->read_only section
1757754b7b63SAndi Kleen# mappings
1758754b7b63SAndi Kleenconfig BROKEN_RODATA
1759754b7b63SAndi Kleen	bool
1760754b7b63SAndi Kleen
17614520c6a4SDavid Howellsconfig ASN1
17624520c6a4SDavid Howells	tristate
17634520c6a4SDavid Howells	help
17644520c6a4SDavid Howells	  Build a simple ASN.1 grammar compiler that produces a bytecode output
17654520c6a4SDavid Howells	  that can be interpreted by the ASN.1 stream decoder and used to
17664520c6a4SDavid Howells	  inform it as to what tags are to be expected in a stream and what
17674520c6a4SDavid Howells	  functions to call on what tags.
17684520c6a4SDavid Howells
17696beb0009SThomas Gleixnersource "kernel/Kconfig.locks"
1770