1config ARCH
2	string
3	option env="ARCH"
4
5config KERNELVERSION
6	string
7	option env="KERNELVERSION"
8
9config DEFCONFIG_LIST
10	string
11	depends on !UML
12	option defconfig_list
13	default "/lib/modules/$UNAME_RELEASE/.config"
14	default "/etc/kernel-config"
15	default "/boot/config-$UNAME_RELEASE"
16	default "$ARCH_DEFCONFIG"
17	default "arch/$ARCH/defconfig"
18
19config CONSTRUCTORS
20	bool
21	depends on !UML
22
23config HAVE_IRQ_WORK
24	bool
25
26config IRQ_WORK
27	bool
28	depends on HAVE_IRQ_WORK
29
30menu "General setup"
31
32config EXPERIMENTAL
33	bool "Prompt for development and/or incomplete code/drivers"
34	---help---
35	  Some of the various things that Linux supports (such as network
36	  drivers, file systems, network protocols, etc.) can be in a state
37	  of development where the functionality, stability, or the level of
38	  testing is not yet high enough for general use. This is usually
39	  known as the "alpha-test" phase among developers. If a feature is
40	  currently in alpha-test, then the developers usually discourage
41	  uninformed widespread use of this feature by the general public to
42	  avoid "Why doesn't this work?" type mail messages. However, active
43	  testing and use of these systems is welcomed. Just be aware that it
44	  may not meet the normal level of reliability or it may fail to work
45	  in some special cases. Detailed bug reports from people familiar
46	  with the kernel internals are usually welcomed by the developers
47	  (before submitting bug reports, please read the documents
48	  <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
49	  <file:Documentation/BUG-HUNTING>, and
50	  <file:Documentation/oops-tracing.txt> in the kernel source).
51
52	  This option will also make obsoleted drivers available. These are
53	  drivers that have been replaced by something else, and/or are
54	  scheduled to be removed in a future kernel release.
55
56	  Unless you intend to help test and develop a feature or driver that
57	  falls into this category, or you have a situation that requires
58	  using these features, you should probably say N here, which will
59	  cause the configurator to present you with fewer choices. If
60	  you say Y here, you will be offered the choice of using features or
61	  drivers that are currently considered to be in the alpha-test phase.
62
63config BROKEN
64	bool
65
66config BROKEN_ON_SMP
67	bool
68	depends on BROKEN || !SMP
69	default y
70
71config INIT_ENV_ARG_LIMIT
72	int
73	default 32 if !UML
74	default 128 if UML
75	help
76	  Maximum of each of the number of arguments and environment
77	  variables passed to init from the kernel command line.
78
79
80config CROSS_COMPILE
81	string "Cross-compiler tool prefix"
82	help
83	  Same as running 'make CROSS_COMPILE=prefix-' but stored for
84	  default make runs in this kernel build directory.  You don't
85	  need to set this unless you want the configured kernel build
86	  directory to select the cross-compiler automatically.
87
88config LOCALVERSION
89	string "Local version - append to kernel release"
90	help
91	  Append an extra string to the end of your kernel version.
92	  This will show up when you type uname, for example.
93	  The string you set here will be appended after the contents of
94	  any files with a filename matching localversion* in your
95	  object and source tree, in that order.  Your total string can
96	  be a maximum of 64 characters.
97
98config LOCALVERSION_AUTO
99	bool "Automatically append version information to the version string"
100	default y
101	help
102	  This will try to automatically determine if the current tree is a
103	  release tree by looking for git tags that belong to the current
104	  top of tree revision.
105
106	  A string of the format -gxxxxxxxx will be added to the localversion
107	  if a git-based tree is found.  The string generated by this will be
108	  appended after any matching localversion* files, and after the value
109	  set in CONFIG_LOCALVERSION.
110
111	  (The actual string used here is the first eight characters produced
112	  by running the command:
113
114	    $ git rev-parse --verify HEAD
115
116	  which is done within the script "scripts/setlocalversion".)
117
118config HAVE_KERNEL_GZIP
119	bool
120
121config HAVE_KERNEL_BZIP2
122	bool
123
124config HAVE_KERNEL_LZMA
125	bool
126
127config HAVE_KERNEL_XZ
128	bool
129
130config HAVE_KERNEL_LZO
131	bool
132
133choice
134	prompt "Kernel compression mode"
135	default KERNEL_GZIP
136	depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO
137	help
138	  The linux kernel is a kind of self-extracting executable.
139	  Several compression algorithms are available, which differ
140	  in efficiency, compression and decompression speed.
141	  Compression speed is only relevant when building a kernel.
142	  Decompression speed is relevant at each boot.
143
144	  If you have any problems with bzip2 or lzma compressed
145	  kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
146	  version of this functionality (bzip2 only), for 2.4, was
147	  supplied by Christian Ludwig)
148
149	  High compression options are mostly useful for users, who
150	  are low on disk space (embedded systems), but for whom ram
151	  size matters less.
152
153	  If in doubt, select 'gzip'
154
155config KERNEL_GZIP
156	bool "Gzip"
157	depends on HAVE_KERNEL_GZIP
158	help
159	  The old and tried gzip compression. It provides a good balance
160	  between compression ratio and decompression speed.
161
162config KERNEL_BZIP2
163	bool "Bzip2"
164	depends on HAVE_KERNEL_BZIP2
165	help
166	  Its compression ratio and speed is intermediate.
167	  Decompression speed is slowest among the three.  The kernel
168	  size is about 10% smaller with bzip2, in comparison to gzip.
169	  Bzip2 uses a large amount of memory. For modern kernels you
170	  will need at least 8MB RAM or more for booting.
171
172config KERNEL_LZMA
173	bool "LZMA"
174	depends on HAVE_KERNEL_LZMA
175	help
176	  The most recent compression algorithm.
177	  Its ratio is best, decompression speed is between the other
178	  two. Compression is slowest.	The kernel size is about 33%
179	  smaller with LZMA in comparison to gzip.
180
181config KERNEL_XZ
182	bool "XZ"
183	depends on HAVE_KERNEL_XZ
184	help
185	  XZ uses the LZMA2 algorithm and instruction set specific
186	  BCJ filters which can improve compression ratio of executable
187	  code. The size of the kernel is about 30% smaller with XZ in
188	  comparison to gzip. On architectures for which there is a BCJ
189	  filter (i386, x86_64, ARM, IA-64, PowerPC, and SPARC), XZ
190	  will create a few percent smaller kernel than plain LZMA.
191
192	  The speed is about the same as with LZMA: The decompression
193	  speed of XZ is better than that of bzip2 but worse than gzip
194	  and LZO. Compression is slow.
195
196config KERNEL_LZO
197	bool "LZO"
198	depends on HAVE_KERNEL_LZO
199	help
200	  Its compression ratio is the poorest among the 4. The kernel
201	  size is about 10% bigger than gzip; however its speed
202	  (both compression and decompression) is the fastest.
203
204endchoice
205
206config DEFAULT_HOSTNAME
207	string "Default hostname"
208	default "(none)"
209	help
210	  This option determines the default system hostname before userspace
211	  calls sethostname(2). The kernel traditionally uses "(none)" here,
212	  but you may wish to use a different default here to make a minimal
213	  system more usable with less configuration.
214
215config SWAP
216	bool "Support for paging of anonymous memory (swap)"
217	depends on MMU && BLOCK
218	default y
219	help
220	  This option allows you to choose whether you want to have support
221	  for so called swap devices or swap files in your kernel that are
222	  used to provide more virtual memory than the actual RAM present
223	  in your computer.  If unsure say Y.
224
225config SYSVIPC
226	bool "System V IPC"
227	---help---
228	  Inter Process Communication is a suite of library functions and
229	  system calls which let processes (running programs) synchronize and
230	  exchange information. It is generally considered to be a good thing,
231	  and some programs won't run unless you say Y here. In particular, if
232	  you want to run the DOS emulator dosemu under Linux (read the
233	  DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
234	  you'll need to say Y here.
235
236	  You can find documentation about IPC with "info ipc" and also in
237	  section 6.4 of the Linux Programmer's Guide, available from
238	  <http://www.tldp.org/guides.html>.
239
240config SYSVIPC_SYSCTL
241	bool
242	depends on SYSVIPC
243	depends on SYSCTL
244	default y
245
246config POSIX_MQUEUE
247	bool "POSIX Message Queues"
248	depends on NET && EXPERIMENTAL
249	---help---
250	  POSIX variant of message queues is a part of IPC. In POSIX message
251	  queues every message has a priority which decides about succession
252	  of receiving it by a process. If you want to compile and run
253	  programs written e.g. for Solaris with use of its POSIX message
254	  queues (functions mq_*) say Y here.
255
256	  POSIX message queues are visible as a filesystem called 'mqueue'
257	  and can be mounted somewhere if you want to do filesystem
258	  operations on message queues.
259
260	  If unsure, say Y.
261
262config POSIX_MQUEUE_SYSCTL
263	bool
264	depends on POSIX_MQUEUE
265	depends on SYSCTL
266	default y
267
268config BSD_PROCESS_ACCT
269	bool "BSD Process Accounting"
270	help
271	  If you say Y here, a user level program will be able to instruct the
272	  kernel (via a special system call) to write process accounting
273	  information to a file: whenever a process exits, information about
274	  that process will be appended to the file by the kernel.  The
275	  information includes things such as creation time, owning user,
276	  command name, memory usage, controlling terminal etc. (the complete
277	  list is in the struct acct in <file:include/linux/acct.h>).  It is
278	  up to the user level program to do useful things with this
279	  information.  This is generally a good idea, so say Y.
280
281config BSD_PROCESS_ACCT_V3
282	bool "BSD Process Accounting version 3 file format"
283	depends on BSD_PROCESS_ACCT
284	default n
285	help
286	  If you say Y here, the process accounting information is written
287	  in a new file format that also logs the process IDs of each
288	  process and it's parent. Note that this file format is incompatible
289	  with previous v0/v1/v2 file formats, so you will need updated tools
290	  for processing it. A preliminary version of these tools is available
291	  at <http://www.gnu.org/software/acct/>.
292
293config FHANDLE
294	bool "open by fhandle syscalls"
295	select EXPORTFS
296	help
297	  If you say Y here, a user level program will be able to map
298	  file names to handle and then later use the handle for
299	  different file system operations. This is useful in implementing
300	  userspace file servers, which now track files using handles instead
301	  of names. The handle would remain the same even if file names
302	  get renamed. Enables open_by_handle_at(2) and name_to_handle_at(2)
303	  syscalls.
304
305config TASKSTATS
306	bool "Export task/process statistics through netlink (EXPERIMENTAL)"
307	depends on NET
308	default n
309	help
310	  Export selected statistics for tasks/processes through the
311	  generic netlink interface. Unlike BSD process accounting, the
312	  statistics are available during the lifetime of tasks/processes as
313	  responses to commands. Like BSD accounting, they are sent to user
314	  space on task exit.
315
316	  Say N if unsure.
317
318config TASK_DELAY_ACCT
319	bool "Enable per-task delay accounting (EXPERIMENTAL)"
320	depends on TASKSTATS
321	help
322	  Collect information on time spent by a task waiting for system
323	  resources like cpu, synchronous block I/O completion and swapping
324	  in pages. Such statistics can help in setting a task's priorities
325	  relative to other tasks for cpu, io, rss limits etc.
326
327	  Say N if unsure.
328
329config TASK_XACCT
330	bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
331	depends on TASKSTATS
332	help
333	  Collect extended task accounting data and send the data
334	  to userland for processing over the taskstats interface.
335
336	  Say N if unsure.
337
338config TASK_IO_ACCOUNTING
339	bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
340	depends on TASK_XACCT
341	help
342	  Collect information on the number of bytes of storage I/O which this
343	  task has caused.
344
345	  Say N if unsure.
346
347config AUDIT
348	bool "Auditing support"
349	depends on NET
350	help
351	  Enable auditing infrastructure that can be used with another
352	  kernel subsystem, such as SELinux (which requires this for
353	  logging of avc messages output).  Does not do system-call
354	  auditing without CONFIG_AUDITSYSCALL.
355
356config AUDITSYSCALL
357	bool "Enable system-call auditing support"
358	depends on AUDIT && (X86 || PPC || S390 || IA64 || UML || SPARC64 || SUPERH || ARM)
359	default y if SECURITY_SELINUX
360	help
361	  Enable low-overhead system-call auditing infrastructure that
362	  can be used independently or with another kernel subsystem,
363	  such as SELinux.
364
365config AUDIT_WATCH
366	def_bool y
367	depends on AUDITSYSCALL
368	select FSNOTIFY
369
370config AUDIT_TREE
371	def_bool y
372	depends on AUDITSYSCALL
373	select FSNOTIFY
374
375config AUDIT_LOGINUID_IMMUTABLE
376	bool "Make audit loginuid immutable"
377	depends on AUDIT
378	help
379	  The config option toggles if a task setting its loginuid requires
380	  CAP_SYS_AUDITCONTROL or if that task should require no special permissions
381	  but should instead only allow setting its loginuid if it was never
382	  previously set.  On systems which use systemd or a similar central
383	  process to restart login services this should be set to true.  On older
384	  systems in which an admin would typically have to directly stop and
385	  start processes this should be set to false.  Setting this to true allows
386	  one to drop potentially dangerous capabilites from the login tasks,
387	  but may not be backwards compatible with older init systems.
388
389source "kernel/irq/Kconfig"
390
391menu "RCU Subsystem"
392
393choice
394	prompt "RCU Implementation"
395	default TREE_RCU
396
397config TREE_RCU
398	bool "Tree-based hierarchical RCU"
399	depends on !PREEMPT && SMP
400	help
401	  This option selects the RCU implementation that is
402	  designed for very large SMP system with hundreds or
403	  thousands of CPUs.  It also scales down nicely to
404	  smaller systems.
405
406config TREE_PREEMPT_RCU
407	bool "Preemptible tree-based hierarchical RCU"
408	depends on PREEMPT && SMP
409	help
410	  This option selects the RCU implementation that is
411	  designed for very large SMP systems with hundreds or
412	  thousands of CPUs, but for which real-time response
413	  is also required.  It also scales down nicely to
414	  smaller systems.
415
416config TINY_RCU
417	bool "UP-only small-memory-footprint RCU"
418	depends on !PREEMPT && !SMP
419	help
420	  This option selects the RCU implementation that is
421	  designed for UP systems from which real-time response
422	  is not required.  This option greatly reduces the
423	  memory footprint of RCU.
424
425config TINY_PREEMPT_RCU
426	bool "Preemptible UP-only small-memory-footprint RCU"
427	depends on PREEMPT && !SMP
428	help
429	  This option selects the RCU implementation that is designed
430	  for real-time UP systems.  This option greatly reduces the
431	  memory footprint of RCU.
432
433endchoice
434
435config PREEMPT_RCU
436	def_bool ( TREE_PREEMPT_RCU || TINY_PREEMPT_RCU )
437	help
438	  This option enables preemptible-RCU code that is common between
439	  the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations.
440
441config RCU_FANOUT
442	int "Tree-based hierarchical RCU fanout value"
443	range 2 64 if 64BIT
444	range 2 32 if !64BIT
445	depends on TREE_RCU || TREE_PREEMPT_RCU
446	default 64 if 64BIT
447	default 32 if !64BIT
448	help
449	  This option controls the fanout of hierarchical implementations
450	  of RCU, allowing RCU to work efficiently on machines with
451	  large numbers of CPUs.  This value must be at least the fourth
452	  root of NR_CPUS, which allows NR_CPUS to be insanely large.
453	  The default value of RCU_FANOUT should be used for production
454	  systems, but if you are stress-testing the RCU implementation
455	  itself, small RCU_FANOUT values allow you to test large-system
456	  code paths on small(er) systems.
457
458	  Select a specific number if testing RCU itself.
459	  Take the default if unsure.
460
461config RCU_FANOUT_EXACT
462	bool "Disable tree-based hierarchical RCU auto-balancing"
463	depends on TREE_RCU || TREE_PREEMPT_RCU
464	default n
465	help
466	  This option forces use of the exact RCU_FANOUT value specified,
467	  regardless of imbalances in the hierarchy.  This is useful for
468	  testing RCU itself, and might one day be useful on systems with
469	  strong NUMA behavior.
470
471	  Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
472
473	  Say N if unsure.
474
475config RCU_FAST_NO_HZ
476	bool "Accelerate last non-dyntick-idle CPU's grace periods"
477	depends on NO_HZ && SMP
478	default n
479	help
480	  This option causes RCU to attempt to accelerate grace periods
481	  in order to allow CPUs to enter dynticks-idle state more
482	  quickly.  On the other hand, this option increases the overhead
483	  of the dynticks-idle checking, particularly on systems with
484	  large numbers of CPUs.
485
486	  Say Y if energy efficiency is critically important, particularly
487	  	if you have relatively few CPUs.
488
489	  Say N if you are unsure.
490
491config TREE_RCU_TRACE
492	def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
493	select DEBUG_FS
494	help
495	  This option provides tracing for the TREE_RCU and
496	  TREE_PREEMPT_RCU implementations, permitting Makefile to
497	  trivially select kernel/rcutree_trace.c.
498
499config RCU_BOOST
500	bool "Enable RCU priority boosting"
501	depends on RT_MUTEXES && PREEMPT_RCU
502	default n
503	help
504	  This option boosts the priority of preempted RCU readers that
505	  block the current preemptible RCU grace period for too long.
506	  This option also prevents heavy loads from blocking RCU
507	  callback invocation for all flavors of RCU.
508
509	  Say Y here if you are working with real-time apps or heavy loads
510	  Say N here if you are unsure.
511
512config RCU_BOOST_PRIO
513	int "Real-time priority to boost RCU readers to"
514	range 1 99
515	depends on RCU_BOOST
516	default 1
517	help
518	  This option specifies the real-time priority to which preempted
519	  RCU readers are to be boosted.  If you are working with CPU-bound
520	  real-time applications, you should specify a priority higher then
521	  the highest-priority CPU-bound application.
522
523	  Specify the real-time priority, or take the default if unsure.
524
525config RCU_BOOST_DELAY
526	int "Milliseconds to delay boosting after RCU grace-period start"
527	range 0 3000
528	depends on RCU_BOOST
529	default 500
530	help
531	  This option specifies the time to wait after the beginning of
532	  a given grace period before priority-boosting preempted RCU
533	  readers blocking that grace period.  Note that any RCU reader
534	  blocking an expedited RCU grace period is boosted immediately.
535
536	  Accept the default if unsure.
537
538endmenu # "RCU Subsystem"
539
540config IKCONFIG
541	tristate "Kernel .config support"
542	---help---
543	  This option enables the complete Linux kernel ".config" file
544	  contents to be saved in the kernel. It provides documentation
545	  of which kernel options are used in a running kernel or in an
546	  on-disk kernel.  This information can be extracted from the kernel
547	  image file with the script scripts/extract-ikconfig and used as
548	  input to rebuild the current kernel or to build another kernel.
549	  It can also be extracted from a running kernel by reading
550	  /proc/config.gz if enabled (below).
551
552config IKCONFIG_PROC
553	bool "Enable access to .config through /proc/config.gz"
554	depends on IKCONFIG && PROC_FS
555	---help---
556	  This option enables access to the kernel configuration file
557	  through /proc/config.gz.
558
559config LOG_BUF_SHIFT
560	int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
561	range 12 21
562	default 17
563	help
564	  Select kernel log buffer size as a power of 2.
565	  Examples:
566	  	     17 => 128 KB
567		     16 => 64 KB
568	             15 => 32 KB
569	             14 => 16 KB
570		     13 =>  8 KB
571		     12 =>  4 KB
572
573#
574# Architectures with an unreliable sched_clock() should select this:
575#
576config HAVE_UNSTABLE_SCHED_CLOCK
577	bool
578
579menuconfig CGROUPS
580	boolean "Control Group support"
581	depends on EVENTFD
582	help
583	  This option adds support for grouping sets of processes together, for
584	  use with process control subsystems such as Cpusets, CFS, memory
585	  controls or device isolation.
586	  See
587		- Documentation/scheduler/sched-design-CFS.txt	(CFS)
588		- Documentation/cgroups/ (features for grouping, isolation
589					  and resource control)
590
591	  Say N if unsure.
592
593if CGROUPS
594
595config CGROUP_DEBUG
596	bool "Example debug cgroup subsystem"
597	default n
598	help
599	  This option enables a simple cgroup subsystem that
600	  exports useful debugging information about the cgroups
601	  framework.
602
603	  Say N if unsure.
604
605config CGROUP_FREEZER
606	bool "Freezer cgroup subsystem"
607	help
608	  Provides a way to freeze and unfreeze all tasks in a
609	  cgroup.
610
611config CGROUP_DEVICE
612	bool "Device controller for cgroups"
613	help
614	  Provides a cgroup implementing whitelists for devices which
615	  a process in the cgroup can mknod or open.
616
617config CPUSETS
618	bool "Cpuset support"
619	help
620	  This option will let you create and manage CPUSETs which
621	  allow dynamically partitioning a system into sets of CPUs and
622	  Memory Nodes and assigning tasks to run only within those sets.
623	  This is primarily useful on large SMP or NUMA systems.
624
625	  Say N if unsure.
626
627config PROC_PID_CPUSET
628	bool "Include legacy /proc/<pid>/cpuset file"
629	depends on CPUSETS
630	default y
631
632config CGROUP_CPUACCT
633	bool "Simple CPU accounting cgroup subsystem"
634	help
635	  Provides a simple Resource Controller for monitoring the
636	  total CPU consumed by the tasks in a cgroup.
637
638config RESOURCE_COUNTERS
639	bool "Resource counters"
640	help
641	  This option enables controller independent resource accounting
642	  infrastructure that works with cgroups.
643
644config CGROUP_MEM_RES_CTLR
645	bool "Memory Resource Controller for Control Groups"
646	depends on RESOURCE_COUNTERS
647	select MM_OWNER
648	help
649	  Provides a memory resource controller that manages both anonymous
650	  memory and page cache. (See Documentation/cgroups/memory.txt)
651
652	  Note that setting this option increases fixed memory overhead
653	  associated with each page of memory in the system. By this,
654	  20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
655	  usage tracking struct at boot. Total amount of this is printed out
656	  at boot.
657
658	  Only enable when you're ok with these trade offs and really
659	  sure you need the memory resource controller. Even when you enable
660	  this, you can set "cgroup_disable=memory" at your boot option to
661	  disable memory resource controller and you can avoid overheads.
662	  (and lose benefits of memory resource controller)
663
664	  This config option also selects MM_OWNER config option, which
665	  could in turn add some fork/exit overhead.
666
667config CGROUP_MEM_RES_CTLR_SWAP
668	bool "Memory Resource Controller Swap Extension"
669	depends on CGROUP_MEM_RES_CTLR && SWAP
670	help
671	  Add swap management feature to memory resource controller. When you
672	  enable this, you can limit mem+swap usage per cgroup. In other words,
673	  when you disable this, memory resource controller has no cares to
674	  usage of swap...a process can exhaust all of the swap. This extension
675	  is useful when you want to avoid exhaustion swap but this itself
676	  adds more overheads and consumes memory for remembering information.
677	  Especially if you use 32bit system or small memory system, please
678	  be careful about enabling this. When memory resource controller
679	  is disabled by boot option, this will be automatically disabled and
680	  there will be no overhead from this. Even when you set this config=y,
681	  if boot option "swapaccount=0" is set, swap will not be accounted.
682	  Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
683	  size is 4096bytes, 512k per 1Gbytes of swap.
684config CGROUP_MEM_RES_CTLR_SWAP_ENABLED
685	bool "Memory Resource Controller Swap Extension enabled by default"
686	depends on CGROUP_MEM_RES_CTLR_SWAP
687	default y
688	help
689	  Memory Resource Controller Swap Extension comes with its price in
690	  a bigger memory consumption. General purpose distribution kernels
691	  which want to enable the feature but keep it disabled by default
692	  and let the user enable it by swapaccount boot command line
693	  parameter should have this option unselected.
694	  For those who want to have the feature enabled by default should
695	  select this option (if, for some reason, they need to disable it
696	  then swapaccount=0 does the trick).
697config CGROUP_MEM_RES_CTLR_KMEM
698	bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
699	depends on CGROUP_MEM_RES_CTLR && EXPERIMENTAL
700	default n
701	help
702	  The Kernel Memory extension for Memory Resource Controller can limit
703	  the amount of memory used by kernel objects in the system. Those are
704	  fundamentally different from the entities handled by the standard
705	  Memory Controller, which are page-based, and can be swapped. Users of
706	  the kmem extension can use it to guarantee that no group of processes
707	  will ever exhaust kernel resources alone.
708
709config CGROUP_PERF
710	bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
711	depends on PERF_EVENTS && CGROUPS
712	help
713	  This option extends the per-cpu mode to restrict monitoring to
714	  threads which belong to the cgroup specified and run on the
715	  designated cpu.
716
717	  Say N if unsure.
718
719menuconfig CGROUP_SCHED
720	bool "Group CPU scheduler"
721	default n
722	help
723	  This feature lets CPU scheduler recognize task groups and control CPU
724	  bandwidth allocation to such task groups. It uses cgroups to group
725	  tasks.
726
727if CGROUP_SCHED
728config FAIR_GROUP_SCHED
729	bool "Group scheduling for SCHED_OTHER"
730	depends on CGROUP_SCHED
731	default CGROUP_SCHED
732
733config CFS_BANDWIDTH
734	bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
735	depends on EXPERIMENTAL
736	depends on FAIR_GROUP_SCHED
737	default n
738	help
739	  This option allows users to define CPU bandwidth rates (limits) for
740	  tasks running within the fair group scheduler.  Groups with no limit
741	  set are considered to be unconstrained and will run with no
742	  restriction.
743	  See tip/Documentation/scheduler/sched-bwc.txt for more information.
744
745config RT_GROUP_SCHED
746	bool "Group scheduling for SCHED_RR/FIFO"
747	depends on EXPERIMENTAL
748	depends on CGROUP_SCHED
749	default n
750	help
751	  This feature lets you explicitly allocate real CPU bandwidth
752	  to task groups. If enabled, it will also make it impossible to
753	  schedule realtime tasks for non-root users until you allocate
754	  realtime bandwidth for them.
755	  See Documentation/scheduler/sched-rt-group.txt for more information.
756
757endif #CGROUP_SCHED
758
759config BLK_CGROUP
760	tristate "Block IO controller"
761	depends on BLOCK
762	default n
763	---help---
764	Generic block IO controller cgroup interface. This is the common
765	cgroup interface which should be used by various IO controlling
766	policies.
767
768	Currently, CFQ IO scheduler uses it to recognize task groups and
769	control disk bandwidth allocation (proportional time slice allocation)
770	to such task groups. It is also used by bio throttling logic in
771	block layer to implement upper limit in IO rates on a device.
772
773	This option only enables generic Block IO controller infrastructure.
774	One needs to also enable actual IO controlling logic/policy. For
775	enabling proportional weight division of disk bandwidth in CFQ, set
776	CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
777	CONFIG_BLK_DEV_THROTTLING=y.
778
779	See Documentation/cgroups/blkio-controller.txt for more information.
780
781config DEBUG_BLK_CGROUP
782	bool "Enable Block IO controller debugging"
783	depends on BLK_CGROUP
784	default n
785	---help---
786	Enable some debugging help. Currently it exports additional stat
787	files in a cgroup which can be useful for debugging.
788
789endif # CGROUPS
790
791config CHECKPOINT_RESTORE
792	bool "Checkpoint/restore support" if EXPERT
793	default n
794	help
795	  Enables additional kernel features in a sake of checkpoint/restore.
796	  In particular it adds auxiliary prctl codes to setup process text,
797	  data and heap segment sizes, and a few additional /proc filesystem
798	  entries.
799
800	  If unsure, say N here.
801
802menuconfig NAMESPACES
803	bool "Namespaces support" if EXPERT
804	default !EXPERT
805	help
806	  Provides the way to make tasks work with different objects using
807	  the same id. For example same IPC id may refer to different objects
808	  or same user id or pid may refer to different tasks when used in
809	  different namespaces.
810
811if NAMESPACES
812
813config UTS_NS
814	bool "UTS namespace"
815	default y
816	help
817	  In this namespace tasks see different info provided with the
818	  uname() system call
819
820config IPC_NS
821	bool "IPC namespace"
822	depends on (SYSVIPC || POSIX_MQUEUE)
823	default y
824	help
825	  In this namespace tasks work with IPC ids which correspond to
826	  different IPC objects in different namespaces.
827
828config USER_NS
829	bool "User namespace (EXPERIMENTAL)"
830	depends on EXPERIMENTAL
831	default y
832	help
833	  This allows containers, i.e. vservers, to use user namespaces
834	  to provide different user info for different servers.
835	  If unsure, say N.
836
837config PID_NS
838	bool "PID Namespaces"
839	default y
840	help
841	  Support process id namespaces.  This allows having multiple
842	  processes with the same pid as long as they are in different
843	  pid namespaces.  This is a building block of containers.
844
845config NET_NS
846	bool "Network namespace"
847	depends on NET
848	default y
849	help
850	  Allow user space to create what appear to be multiple instances
851	  of the network stack.
852
853endif # NAMESPACES
854
855config SCHED_AUTOGROUP
856	bool "Automatic process group scheduling"
857	select EVENTFD
858	select CGROUPS
859	select CGROUP_SCHED
860	select FAIR_GROUP_SCHED
861	help
862	  This option optimizes the scheduler for common desktop workloads by
863	  automatically creating and populating task groups.  This separation
864	  of workloads isolates aggressive CPU burners (like build jobs) from
865	  desktop applications.  Task group autogeneration is currently based
866	  upon task session.
867
868config MM_OWNER
869	bool
870
871config SYSFS_DEPRECATED
872	bool "Enable deprecated sysfs features to support old userspace tools"
873	depends on SYSFS
874	default n
875	help
876	  This option adds code that switches the layout of the "block" class
877	  devices, to not show up in /sys/class/block/, but only in
878	  /sys/block/.
879
880	  This switch is only active when the sysfs.deprecated=1 boot option is
881	  passed or the SYSFS_DEPRECATED_V2 option is set.
882
883	  This option allows new kernels to run on old distributions and tools,
884	  which might get confused by /sys/class/block/. Since 2007/2008 all
885	  major distributions and tools handle this just fine.
886
887	  Recent distributions and userspace tools after 2009/2010 depend on
888	  the existence of /sys/class/block/, and will not work with this
889	  option enabled.
890
891	  Only if you are using a new kernel on an old distribution, you might
892	  need to say Y here.
893
894config SYSFS_DEPRECATED_V2
895	bool "Enable deprecated sysfs features by default"
896	default n
897	depends on SYSFS
898	depends on SYSFS_DEPRECATED
899	help
900	  Enable deprecated sysfs by default.
901
902	  See the CONFIG_SYSFS_DEPRECATED option for more details about this
903	  option.
904
905	  Only if you are using a new kernel on an old distribution, you might
906	  need to say Y here. Even then, odds are you would not need it
907	  enabled, you can always pass the boot option if absolutely necessary.
908
909config RELAY
910	bool "Kernel->user space relay support (formerly relayfs)"
911	help
912	  This option enables support for relay interface support in
913	  certain file systems (such as debugfs).
914	  It is designed to provide an efficient mechanism for tools and
915	  facilities to relay large amounts of data from kernel space to
916	  user space.
917
918	  If unsure, say N.
919
920config BLK_DEV_INITRD
921	bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
922	depends on BROKEN || !FRV
923	help
924	  The initial RAM filesystem is a ramfs which is loaded by the
925	  boot loader (loadlin or lilo) and that is mounted as root
926	  before the normal boot procedure. It is typically used to
927	  load modules needed to mount the "real" root file system,
928	  etc. See <file:Documentation/initrd.txt> for details.
929
930	  If RAM disk support (BLK_DEV_RAM) is also included, this
931	  also enables initial RAM disk (initrd) support and adds
932	  15 Kbytes (more on some other architectures) to the kernel size.
933
934	  If unsure say Y.
935
936if BLK_DEV_INITRD
937
938source "usr/Kconfig"
939
940endif
941
942config CC_OPTIMIZE_FOR_SIZE
943	bool "Optimize for size"
944	help
945	  Enabling this option will pass "-Os" instead of "-O2" to gcc
946	  resulting in a smaller kernel.
947
948	  If unsure, say Y.
949
950config SYSCTL
951	bool
952
953config ANON_INODES
954	bool
955
956menuconfig EXPERT
957	bool "Configure standard kernel features (expert users)"
958	# Unhide debug options, to make the on-by-default options visible
959	select DEBUG_KERNEL
960	help
961	  This option allows certain base kernel options and settings
962          to be disabled or tweaked. This is for specialized
963          environments which can tolerate a "non-standard" kernel.
964          Only use this if you really know what you are doing.
965
966config UID16
967	bool "Enable 16-bit UID system calls" if EXPERT
968	depends on ARM || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && COMPAT) || UML || (X86_64 && IA32_EMULATION)
969	default y
970	help
971	  This enables the legacy 16-bit UID syscall wrappers.
972
973config SYSCTL_SYSCALL
974	bool "Sysctl syscall support" if EXPERT
975	depends on PROC_SYSCTL
976	default n
977	select SYSCTL
978	---help---
979	  sys_sysctl uses binary paths that have been found challenging
980	  to properly maintain and use.  The interface in /proc/sys
981	  using paths with ascii names is now the primary path to this
982	  information.
983
984	  Almost nothing using the binary sysctl interface so if you are
985	  trying to save some space it is probably safe to disable this,
986	  making your kernel marginally smaller.
987
988	  If unsure say N here.
989
990config KALLSYMS
991	 bool "Load all symbols for debugging/ksymoops" if EXPERT
992	 default y
993	 help
994	   Say Y here to let the kernel print out symbolic crash information and
995	   symbolic stack backtraces. This increases the size of the kernel
996	   somewhat, as all symbols have to be loaded into the kernel image.
997
998config KALLSYMS_ALL
999	bool "Include all symbols in kallsyms"
1000	depends on DEBUG_KERNEL && KALLSYMS
1001	help
1002	   Normally kallsyms only contains the symbols of functions for nicer
1003	   OOPS messages and backtraces (i.e., symbols from the text and inittext
1004	   sections). This is sufficient for most cases. And only in very rare
1005	   cases (e.g., when a debugger is used) all symbols are required (e.g.,
1006	   names of variables from the data sections, etc).
1007
1008	   This option makes sure that all symbols are loaded into the kernel
1009	   image (i.e., symbols from all sections) in cost of increased kernel
1010	   size (depending on the kernel configuration, it may be 300KiB or
1011	   something like this).
1012
1013	   Say N unless you really need all symbols.
1014
1015config HOTPLUG
1016	bool "Support for hot-pluggable devices" if EXPERT
1017	default y
1018	help
1019	  This option is provided for the case where no hotplug or uevent
1020	  capabilities is wanted by the kernel.  You should only consider
1021	  disabling this option for embedded systems that do not use modules, a
1022	  dynamic /dev tree, or dynamic device discovery.  Just say Y.
1023
1024config PRINTK
1025	default y
1026	bool "Enable support for printk" if EXPERT
1027	help
1028	  This option enables normal printk support. Removing it
1029	  eliminates most of the message strings from the kernel image
1030	  and makes the kernel more or less silent. As this makes it
1031	  very difficult to diagnose system problems, saying N here is
1032	  strongly discouraged.
1033
1034config BUG
1035	bool "BUG() support" if EXPERT
1036	default y
1037	help
1038          Disabling this option eliminates support for BUG and WARN, reducing
1039          the size of your kernel image and potentially quietly ignoring
1040          numerous fatal conditions. You should only consider disabling this
1041          option for embedded systems with no facilities for reporting errors.
1042          Just say Y.
1043
1044config ELF_CORE
1045	default y
1046	bool "Enable ELF core dumps" if EXPERT
1047	help
1048	  Enable support for generating core dumps. Disabling saves about 4k.
1049
1050
1051config PCSPKR_PLATFORM
1052	bool "Enable PC-Speaker support" if EXPERT
1053	depends on HAVE_PCSPKR_PLATFORM
1054	select I8253_LOCK
1055	default y
1056	help
1057          This option allows to disable the internal PC-Speaker
1058          support, saving some memory.
1059
1060config HAVE_PCSPKR_PLATFORM
1061	bool
1062
1063config BASE_FULL
1064	default y
1065	bool "Enable full-sized data structures for core" if EXPERT
1066	help
1067	  Disabling this option reduces the size of miscellaneous core
1068	  kernel data structures. This saves memory on small machines,
1069	  but may reduce performance.
1070
1071config FUTEX
1072	bool "Enable futex support" if EXPERT
1073	default y
1074	select RT_MUTEXES
1075	help
1076	  Disabling this option will cause the kernel to be built without
1077	  support for "fast userspace mutexes".  The resulting kernel may not
1078	  run glibc-based applications correctly.
1079
1080config EPOLL
1081	bool "Enable eventpoll support" if EXPERT
1082	default y
1083	select ANON_INODES
1084	help
1085	  Disabling this option will cause the kernel to be built without
1086	  support for epoll family of system calls.
1087
1088config SIGNALFD
1089	bool "Enable signalfd() system call" if EXPERT
1090	select ANON_INODES
1091	default y
1092	help
1093	  Enable the signalfd() system call that allows to receive signals
1094	  on a file descriptor.
1095
1096	  If unsure, say Y.
1097
1098config TIMERFD
1099	bool "Enable timerfd() system call" if EXPERT
1100	select ANON_INODES
1101	default y
1102	help
1103	  Enable the timerfd() system call that allows to receive timer
1104	  events on a file descriptor.
1105
1106	  If unsure, say Y.
1107
1108config EVENTFD
1109	bool "Enable eventfd() system call" if EXPERT
1110	select ANON_INODES
1111	default y
1112	help
1113	  Enable the eventfd() system call that allows to receive both
1114	  kernel notification (ie. KAIO) or userspace notifications.
1115
1116	  If unsure, say Y.
1117
1118config SHMEM
1119	bool "Use full shmem filesystem" if EXPERT
1120	default y
1121	depends on MMU
1122	help
1123	  The shmem is an internal filesystem used to manage shared memory.
1124	  It is backed by swap and manages resource limits. It is also exported
1125	  to userspace as tmpfs if TMPFS is enabled. Disabling this
1126	  option replaces shmem and tmpfs with the much simpler ramfs code,
1127	  which may be appropriate on small systems without swap.
1128
1129config AIO
1130	bool "Enable AIO support" if EXPERT
1131	default y
1132	help
1133	  This option enables POSIX asynchronous I/O which may by used
1134          by some high performance threaded applications. Disabling
1135          this option saves about 7k.
1136
1137config EMBEDDED
1138	bool "Embedded system"
1139	select EXPERT
1140	help
1141	  This option should be enabled if compiling the kernel for
1142	  an embedded system so certain expert options are available
1143	  for configuration.
1144
1145config HAVE_PERF_EVENTS
1146	bool
1147	help
1148	  See tools/perf/design.txt for details.
1149
1150config PERF_USE_VMALLOC
1151	bool
1152	help
1153	  See tools/perf/design.txt for details
1154
1155menu "Kernel Performance Events And Counters"
1156
1157config PERF_EVENTS
1158	bool "Kernel performance events and counters"
1159	default y if (PROFILING || PERF_COUNTERS)
1160	depends on HAVE_PERF_EVENTS
1161	select ANON_INODES
1162	select IRQ_WORK
1163	help
1164	  Enable kernel support for various performance events provided
1165	  by software and hardware.
1166
1167	  Software events are supported either built-in or via the
1168	  use of generic tracepoints.
1169
1170	  Most modern CPUs support performance events via performance
1171	  counter registers. These registers count the number of certain
1172	  types of hw events: such as instructions executed, cachemisses
1173	  suffered, or branches mis-predicted - without slowing down the
1174	  kernel or applications. These registers can also trigger interrupts
1175	  when a threshold number of events have passed - and can thus be
1176	  used to profile the code that runs on that CPU.
1177
1178	  The Linux Performance Event subsystem provides an abstraction of
1179	  these software and hardware event capabilities, available via a
1180	  system call and used by the "perf" utility in tools/perf/. It
1181	  provides per task and per CPU counters, and it provides event
1182	  capabilities on top of those.
1183
1184	  Say Y if unsure.
1185
1186config PERF_COUNTERS
1187	bool "Kernel performance counters (old config option)"
1188	depends on HAVE_PERF_EVENTS
1189	help
1190	  This config has been obsoleted by the PERF_EVENTS
1191	  config option - please see that one for details.
1192
1193	  It has no effect on the kernel whether you enable
1194	  it or not, it is a compatibility placeholder.
1195
1196	  Say N if unsure.
1197
1198config DEBUG_PERF_USE_VMALLOC
1199	default n
1200	bool "Debug: use vmalloc to back perf mmap() buffers"
1201	depends on PERF_EVENTS && DEBUG_KERNEL
1202	select PERF_USE_VMALLOC
1203	help
1204	 Use vmalloc memory to back perf mmap() buffers.
1205
1206	 Mostly useful for debugging the vmalloc code on platforms
1207	 that don't require it.
1208
1209	 Say N if unsure.
1210
1211endmenu
1212
1213config VM_EVENT_COUNTERS
1214	default y
1215	bool "Enable VM event counters for /proc/vmstat" if EXPERT
1216	help
1217	  VM event counters are needed for event counts to be shown.
1218	  This option allows the disabling of the VM event counters
1219	  on EXPERT systems.  /proc/vmstat will only show page counts
1220	  if VM event counters are disabled.
1221
1222config PCI_QUIRKS
1223	default y
1224	bool "Enable PCI quirk workarounds" if EXPERT
1225	depends on PCI
1226	help
1227	  This enables workarounds for various PCI chipset
1228          bugs/quirks. Disable this only if your target machine is
1229          unaffected by PCI quirks.
1230
1231config SLUB_DEBUG
1232	default y
1233	bool "Enable SLUB debugging support" if EXPERT
1234	depends on SLUB && SYSFS
1235	help
1236	  SLUB has extensive debug support features. Disabling these can
1237	  result in significant savings in code size. This also disables
1238	  SLUB sysfs support. /sys/slab will not exist and there will be
1239	  no support for cache validation etc.
1240
1241config COMPAT_BRK
1242	bool "Disable heap randomization"
1243	default y
1244	help
1245	  Randomizing heap placement makes heap exploits harder, but it
1246	  also breaks ancient binaries (including anything libc5 based).
1247	  This option changes the bootup default to heap randomization
1248	  disabled, and can be overridden at runtime by setting
1249	  /proc/sys/kernel/randomize_va_space to 2.
1250
1251	  On non-ancient distros (post-2000 ones) N is usually a safe choice.
1252
1253choice
1254	prompt "Choose SLAB allocator"
1255	default SLUB
1256	help
1257	   This option allows to select a slab allocator.
1258
1259config SLAB
1260	bool "SLAB"
1261	help
1262	  The regular slab allocator that is established and known to work
1263	  well in all environments. It organizes cache hot objects in
1264	  per cpu and per node queues.
1265
1266config SLUB
1267	bool "SLUB (Unqueued Allocator)"
1268	help
1269	   SLUB is a slab allocator that minimizes cache line usage
1270	   instead of managing queues of cached objects (SLAB approach).
1271	   Per cpu caching is realized using slabs of objects instead
1272	   of queues of objects. SLUB can use memory efficiently
1273	   and has enhanced diagnostics. SLUB is the default choice for
1274	   a slab allocator.
1275
1276config SLOB
1277	depends on EXPERT
1278	bool "SLOB (Simple Allocator)"
1279	help
1280	   SLOB replaces the stock allocator with a drastically simpler
1281	   allocator. SLOB is generally more space efficient but
1282	   does not perform as well on large systems.
1283
1284endchoice
1285
1286config MMAP_ALLOW_UNINITIALIZED
1287	bool "Allow mmapped anonymous memory to be uninitialized"
1288	depends on EXPERT && !MMU
1289	default n
1290	help
1291	  Normally, and according to the Linux spec, anonymous memory obtained
1292	  from mmap() has it's contents cleared before it is passed to
1293	  userspace.  Enabling this config option allows you to request that
1294	  mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus
1295	  providing a huge performance boost.  If this option is not enabled,
1296	  then the flag will be ignored.
1297
1298	  This is taken advantage of by uClibc's malloc(), and also by
1299	  ELF-FDPIC binfmt's brk and stack allocator.
1300
1301	  Because of the obvious security issues, this option should only be
1302	  enabled on embedded devices where you control what is run in
1303	  userspace.  Since that isn't generally a problem on no-MMU systems,
1304	  it is normally safe to say Y here.
1305
1306	  See Documentation/nommu-mmap.txt for more information.
1307
1308config PROFILING
1309	bool "Profiling support"
1310	help
1311	  Say Y here to enable the extended profiling support mechanisms used
1312	  by profilers such as OProfile.
1313
1314#
1315# Place an empty function call at each tracepoint site. Can be
1316# dynamically changed for a probe function.
1317#
1318config TRACEPOINTS
1319	bool
1320
1321source "arch/Kconfig"
1322
1323endmenu		# General setup
1324
1325config HAVE_GENERIC_DMA_COHERENT
1326	bool
1327	default n
1328
1329config SLABINFO
1330	bool
1331	depends on PROC_FS
1332	depends on SLAB || SLUB_DEBUG
1333	default y
1334
1335config RT_MUTEXES
1336	boolean
1337
1338config BASE_SMALL
1339	int
1340	default 0 if BASE_FULL
1341	default 1 if !BASE_FULL
1342
1343menuconfig MODULES
1344	bool "Enable loadable module support"
1345	help
1346	  Kernel modules are small pieces of compiled code which can
1347	  be inserted in the running kernel, rather than being
1348	  permanently built into the kernel.  You use the "modprobe"
1349	  tool to add (and sometimes remove) them.  If you say Y here,
1350	  many parts of the kernel can be built as modules (by
1351	  answering M instead of Y where indicated): this is most
1352	  useful for infrequently used options which are not required
1353	  for booting.  For more information, see the man pages for
1354	  modprobe, lsmod, modinfo, insmod and rmmod.
1355
1356	  If you say Y here, you will need to run "make
1357	  modules_install" to put the modules under /lib/modules/
1358	  where modprobe can find them (you may need to be root to do
1359	  this).
1360
1361	  If unsure, say Y.
1362
1363if MODULES
1364
1365config MODULE_FORCE_LOAD
1366	bool "Forced module loading"
1367	default n
1368	help
1369	  Allow loading of modules without version information (ie. modprobe
1370	  --force).  Forced module loading sets the 'F' (forced) taint flag and
1371	  is usually a really bad idea.
1372
1373config MODULE_UNLOAD
1374	bool "Module unloading"
1375	help
1376	  Without this option you will not be able to unload any
1377	  modules (note that some modules may not be unloadable
1378	  anyway), which makes your kernel smaller, faster
1379	  and simpler.  If unsure, say Y.
1380
1381config MODULE_FORCE_UNLOAD
1382	bool "Forced module unloading"
1383	depends on MODULE_UNLOAD && EXPERIMENTAL
1384	help
1385	  This option allows you to force a module to unload, even if the
1386	  kernel believes it is unsafe: the kernel will remove the module
1387	  without waiting for anyone to stop using it (using the -f option to
1388	  rmmod).  This is mainly for kernel developers and desperate users.
1389	  If unsure, say N.
1390
1391config MODVERSIONS
1392	bool "Module versioning support"
1393	help
1394	  Usually, you have to use modules compiled with your kernel.
1395	  Saying Y here makes it sometimes possible to use modules
1396	  compiled for different kernels, by adding enough information
1397	  to the modules to (hopefully) spot any changes which would
1398	  make them incompatible with the kernel you are running.  If
1399	  unsure, say N.
1400
1401config MODULE_SRCVERSION_ALL
1402	bool "Source checksum for all modules"
1403	help
1404	  Modules which contain a MODULE_VERSION get an extra "srcversion"
1405	  field inserted into their modinfo section, which contains a
1406    	  sum of the source files which made it.  This helps maintainers
1407	  see exactly which source was used to build a module (since
1408	  others sometimes change the module source without updating
1409	  the version).  With this option, such a "srcversion" field
1410	  will be created for all modules.  If unsure, say N.
1411
1412endif # MODULES
1413
1414config INIT_ALL_POSSIBLE
1415	bool
1416	help
1417	  Back when each arch used to define their own cpu_online_mask and
1418	  cpu_possible_mask, some of them chose to initialize cpu_possible_mask
1419	  with all 1s, and others with all 0s.  When they were centralised,
1420	  it was better to provide this option than to break all the archs
1421	  and have several arch maintainers pursuing me down dark alleys.
1422
1423config STOP_MACHINE
1424	bool
1425	default y
1426	depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
1427	help
1428	  Need stop_machine() primitive.
1429
1430source "block/Kconfig"
1431
1432config PREEMPT_NOTIFIERS
1433	bool
1434
1435config PADATA
1436	depends on SMP
1437	bool
1438
1439source "kernel/Kconfig.locks"
1440