kernel: Use new symbol to deactivate MIPS FPU support
[openwrt/staging/wigyori.git] / config / Config-kernel.in
1 # Copyright (C) 2006-2014 OpenWrt.org
2 #
3 # This is free software, licensed under the GNU General Public License v2.
4 # See /LICENSE for more information.
5 #
6
7 config KERNEL_BUILD_USER
8 string "Custom Kernel Build User Name"
9 default "builder" if BUILDBOT
10 default ""
11 help
12 Sets the Kernel build user string, which for example will be returned
13 by 'uname -a' on running systems.
14 If not set, uses system user at build time.
15
16 config KERNEL_BUILD_DOMAIN
17 string "Custom Kernel Build Domain Name"
18 default "buildhost" if BUILDBOT
19 default ""
20 help
21 Sets the Kernel build domain string, which for example will be
22 returned by 'uname -a' on running systems.
23 If not set, uses system hostname at build time.
24
25 config KERNEL_PRINTK
26 bool "Enable support for printk"
27 default y
28
29 config KERNEL_CRASHLOG
30 bool "Crash logging"
31 depends on !(arm || powerpc || sparc || TARGET_uml || i386 || x86_64)
32 default y
33
34 config KERNEL_SWAP
35 bool "Support for paging of anonymous memory (swap)"
36 default y if !SMALL_FLASH
37
38 config KERNEL_DEBUG_FS
39 bool "Compile the kernel with debug filesystem enabled"
40 default y
41 help
42 debugfs is a virtual file system that kernel developers use to put
43 debugging files into. Enable this option to be able to read and
44 write to these files. Many common debugging facilities, such as
45 ftrace, require the existence of debugfs.
46
47 # remove KERNEL_MIPS_FPU_EMULATOR after kernel 4.14 and 4.14 are gone
48 config KERNEL_MIPS_FPU_EMULATOR
49 bool "Compile the kernel with MIPS FPU Emulator"
50 default y if TARGET_pistachio
51 depends on (mips || mipsel || mips64 || mips64el)
52
53 config KERNEL_MIPS_FP_SUPPORT
54 bool
55 default y if KERNEL_MIPS_FPU_EMULATOR
56
57 config KERNEL_ARM_PMU
58 bool
59 default n
60 depends on (arm || aarch64)
61
62 config KERNEL_X86_VSYSCALL_EMULATION
63 bool "Enable vsyscall emulation"
64 default n
65 depends on x86_64
66 help
67 This enables emulation of the legacy vsyscall page. Disabling
68 it is roughly equivalent to booting with vsyscall=none, except
69 that it will also disable the helpful warning if a program
70 tries to use a vsyscall. With this option set to N, offending
71 programs will just segfault, citing addresses of the form
72 0xffffffffff600?00.
73
74 This option is required by many programs built before 2013, and
75 care should be used even with newer programs if set to N.
76
77 Disabling this option saves about 7K of kernel size and
78 possibly 4K of additional runtime pagetable memory.
79
80 config KERNEL_PERF_EVENTS
81 bool "Compile the kernel with performance events and counters"
82 default n
83 select KERNEL_ARM_PMU if (arm || aarch64)
84
85 config KERNEL_PROFILING
86 bool "Compile the kernel with profiling enabled"
87 default n
88 select KERNEL_PERF_EVENTS
89 help
90 Enable the extended profiling support mechanisms used by profilers such
91 as OProfile.
92
93 config KERNEL_UBSAN
94 bool "Compile the kernel with undefined behaviour sanity checker"
95 help
96 This option enables undefined behaviour sanity checker
97 Compile-time instrumentation is used to detect various undefined
98 behaviours in runtime. Various types of checks may be enabled
99 via boot parameter ubsan_handle
100 (see: Documentation/dev-tools/ubsan.rst).
101
102 config KERNEL_UBSAN_SANITIZE_ALL
103 bool "Enable instrumentation for the entire kernel"
104 depends on KERNEL_UBSAN
105 default y
106 help
107 This option activates instrumentation for the entire kernel.
108 If you don't enable this option, you have to explicitly specify
109 UBSAN_SANITIZE := y for the files/directories you want to check for UB.
110 Enabling this option will get kernel image size increased
111 significantly.
112
113 config KERNEL_UBSAN_ALIGNMENT
114 bool "Enable checking of pointers alignment"
115 depends on KERNEL_UBSAN
116 help
117 This option enables detection of unaligned memory accesses.
118 Enabling this option on architectures that support unaligned
119 accesses may produce a lot of false positives.
120
121 config KERNEL_UBSAN_NULL
122 bool "Enable checking of null pointers"
123 depends on KERNEL_UBSAN
124 help
125 This option enables detection of memory accesses via a
126 null pointer.
127
128 config KERNEL_KASAN
129 bool "Compile the kernel with KASan: runtime memory debugger"
130 select KERNEL_SLUB_DEBUG
131 depends on (x86_64 || aarch64)
132 help
133 Enables kernel address sanitizer - runtime memory debugger,
134 designed to find out-of-bounds accesses and use-after-free bugs.
135 This is strictly a debugging feature and it requires a gcc version
136 of 4.9.2 or later. Detection of out of bounds accesses to stack or
137 global variables requires gcc 5.0 or later.
138 This feature consumes about 1/8 of available memory and brings about
139 ~x3 performance slowdown.
140 For better error detection enable CONFIG_STACKTRACE.
141 Currently CONFIG_KASAN doesn't work with CONFIG_DEBUG_SLAB
142 (the resulting kernel does not boot).
143
144 config KERNEL_KASAN_EXTRA
145 bool "KAsan: extra checks"
146 depends on KERNEL_KASAN && KERNEL_DEBUG_KERNEL
147 help
148 This enables further checks in the kernel address sanitizer, for now
149 it only includes the address-use-after-scope check that can lead
150 to excessive kernel stack usage, frame size warnings and longer
151 compile time.
152 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 has more
153
154
155 choice
156 prompt "Instrumentation type"
157 depends on KERNEL_KASAN
158 default KERNEL_KASAN_OUTLINE
159
160 config KERNEL_KASAN_OUTLINE
161 bool "Outline instrumentation"
162 help
163 Before every memory access compiler insert function call
164 __asan_load*/__asan_store*. These functions performs check
165 of shadow memory. This is slower than inline instrumentation,
166 however it doesn't bloat size of kernel's .text section so
167 much as inline does.
168
169 config KERNEL_KASAN_INLINE
170 bool "Inline instrumentation"
171 help
172 Compiler directly inserts code checking shadow memory before
173 memory accesses. This is faster than outline (in some workloads
174 it gives about x2 boost over outline instrumentation), but
175 make kernel's .text size much bigger.
176 This requires a gcc version of 5.0 or later.
177
178 endchoice
179
180 config KERNEL_KCOV
181 bool "Compile the kernel with code coverage for fuzzing"
182 select KERNEL_DEBUG_FS
183 help
184 KCOV exposes kernel code coverage information in a form suitable
185 for coverage-guided fuzzing (randomized testing).
186
187 If RANDOMIZE_BASE is enabled, PC values will not be stable across
188 different machines and across reboots. If you need stable PC values,
189 disable RANDOMIZE_BASE.
190
191 For more details, see Documentation/kcov.txt.
192
193 config KERNEL_KCOV_ENABLE_COMPARISONS
194 bool "Enable comparison operands collection by KCOV"
195 depends on KERNEL_KCOV
196 help
197 KCOV also exposes operands of every comparison in the instrumented
198 code along with operand sizes and PCs of the comparison instructions.
199 These operands can be used by fuzzing engines to improve the quality
200 of fuzzing coverage.
201
202 config KERNEL_KCOV_INSTRUMENT_ALL
203 bool "Instrument all code by default"
204 depends on KERNEL_KCOV
205 default y if KERNEL_KCOV
206 help
207 If you are doing generic system call fuzzing (like e.g. syzkaller),
208 then you will want to instrument the whole kernel and you should
209 say y here. If you are doing more targeted fuzzing (like e.g.
210 filesystem fuzzing with AFL) then you will want to enable coverage
211 for more specific subsets of files, and should say n here.
212
213 config KERNEL_TASKSTATS
214 bool "Compile the kernel with task resource/io statistics and accounting"
215 default n
216 help
217 Enable the collection and publishing of task/io statistics and
218 accounting. Enable this option to enable i/o monitoring in system
219 monitors.
220
221 if KERNEL_TASKSTATS
222
223 config KERNEL_TASK_DELAY_ACCT
224 def_bool y
225
226 config KERNEL_TASK_IO_ACCOUNTING
227 def_bool y
228
229 config KERNEL_TASK_XACCT
230 def_bool y
231
232 endif
233
234 config KERNEL_KALLSYMS
235 bool "Compile the kernel with symbol table information"
236 default y if !SMALL_FLASH
237 help
238 This will give you more information in stack traces from kernel oopses.
239
240 config KERNEL_FTRACE
241 bool "Compile the kernel with tracing support"
242 depends on !TARGET_uml
243 default n
244
245 config KERNEL_FTRACE_SYSCALLS
246 bool "Trace system calls"
247 depends on KERNEL_FTRACE
248 default n
249
250 config KERNEL_ENABLE_DEFAULT_TRACERS
251 bool "Trace process context switches and events"
252 depends on KERNEL_FTRACE
253 default n
254
255 config KERNEL_FUNCTION_TRACER
256 bool "Function tracer"
257 depends on KERNEL_FTRACE
258 default n
259
260 config KERNEL_FUNCTION_GRAPH_TRACER
261 bool "Function graph tracer"
262 depends on KERNEL_FUNCTION_TRACER
263 default n
264
265 config KERNEL_DYNAMIC_FTRACE
266 bool "Enable/disable function tracing dynamically"
267 depends on KERNEL_FUNCTION_TRACER
268 default n
269
270 config KERNEL_FUNCTION_PROFILER
271 bool "Function profiler"
272 depends on KERNEL_FUNCTION_TRACER
273 default n
274
275 config KERNEL_DEBUG_KERNEL
276 bool
277 default n
278
279 config KERNEL_DEBUG_INFO
280 bool "Compile the kernel with debug information"
281 default y if !SMALL_FLASH
282 select KERNEL_DEBUG_KERNEL
283 help
284 This will compile your kernel and modules with debug information.
285
286 config KERNEL_DEBUG_LL_UART_NONE
287 bool
288 default n
289 depends on arm
290
291 config KERNEL_DEBUG_LL
292 bool
293 default n
294 depends on arm
295 select KERNEL_DEBUG_LL_UART_NONE
296 help
297 ARM low level debugging.
298
299 config KERNEL_DYNAMIC_DEBUG
300 bool "Compile the kernel with dynamic printk"
301 select KERNEL_DEBUG_FS
302 default n
303 help
304 Compiles debug level messages into the kernel, which would not
305 otherwise be available at runtime. These messages can then be
306 enabled/disabled based on various levels of scope - per source file,
307 function, module, format string, and line number. This mechanism
308 implicitly compiles in all pr_debug() and dev_dbg() calls, which
309 enlarges the kernel text size by about 2%.
310
311 config KERNEL_EARLY_PRINTK
312 bool "Compile the kernel with early printk"
313 default y if TARGET_bcm53xx
314 default n
315 depends on arm
316 select KERNEL_DEBUG_KERNEL
317 select KERNEL_DEBUG_LL if arm
318 help
319 Compile the kernel with early printk support. This is only useful for
320 debugging purposes to send messages over the serial console in early boot.
321 Enable this to debug early boot problems.
322
323 config KERNEL_KPROBES
324 bool "Compile the kernel with kprobes support"
325 default n
326 select KERNEL_FTRACE
327 select KERNEL_PERF_EVENTS
328 help
329 Compiles the kernel with KPROBES support, which allows you to trap
330 at almost any kernel address and execute a callback function.
331 register_kprobe() establishes a probepoint and specifies the
332 callback. Kprobes is useful for kernel debugging, non-intrusive
333 instrumentation and testing.
334 If in doubt, say "N".
335
336 config KERNEL_KPROBE_EVENT
337 bool
338 default y if KERNEL_KPROBES
339
340 config KERNEL_KPROBE_EVENTS
341 bool
342 default y if KERNEL_KPROBES
343
344 config KERNEL_AIO
345 bool "Compile the kernel with asynchronous IO support"
346 default y if !SMALL_FLASH
347
348 config KERNEL_FHANDLE
349 bool "Compile the kernel with support for fhandle syscalls"
350 default y if !SMALL_FLASH
351
352 config KERNEL_FANOTIFY
353 bool "Compile the kernel with modern file notification support"
354 default y if !SMALL_FLASH
355
356 config KERNEL_BLK_DEV_BSG
357 bool "Compile the kernel with SCSI generic v4 support for any block device"
358 default n
359
360 config KERNEL_MAGIC_SYSRQ
361 bool "Compile the kernel with SysRq support"
362 default y
363
364 config KERNEL_DEBUG_PINCTRL
365 bool "Compile the kernel with pinctrl debugging"
366 select KERNEL_DEBUG_KERNEL
367
368 config KERNEL_DEBUG_GPIO
369 bool "Compile the kernel with gpio debugging"
370 select KERNEL_DEBUG_KERNEL
371
372 config KERNEL_COREDUMP
373 bool
374
375 config KERNEL_ELF_CORE
376 bool "Enable process core dump support"
377 select KERNEL_COREDUMP
378 default y if !SMALL_FLASH
379
380 config KERNEL_PROVE_LOCKING
381 bool "Enable kernel lock checking"
382 select KERNEL_DEBUG_KERNEL
383 default n
384
385 config KERNEL_LOCKUP_DETECTOR
386 bool "Compile the kernel with detect Hard and Soft Lockups"
387 depends on KERNEL_DEBUG_KERNEL
388 help
389 Say Y here to enable the kernel to act as a watchdog to detect
390 hard and soft lockups.
391
392 Softlockups are bugs that cause the kernel to loop in kernel
393 mode for more than 20 seconds, without giving other tasks a
394 chance to run. The current stack trace is displayed upon
395 detection and the system will stay locked up.
396
397 Hardlockups are bugs that cause the CPU to loop in kernel mode
398 for more than 10 seconds, without letting other interrupts have a
399 chance to run. The current stack trace is displayed upon detection
400 and the system will stay locked up.
401
402 The overhead should be minimal. A periodic hrtimer runs to
403 generate interrupts and kick the watchdog task every 4 seconds.
404 An NMI is generated every 10 seconds or so to check for hardlockups.
405
406 The frequency of hrtimer and NMI events and the soft and hard lockup
407 thresholds can be controlled through the sysctl watchdog_thresh.
408
409 config KERNEL_DETECT_HUNG_TASK
410 bool "Compile the kernel with detect Hung Tasks"
411 depends on KERNEL_DEBUG_KERNEL
412 default KERNEL_LOCKUP_DETECTOR
413 help
414 Say Y here to enable the kernel to detect "hung tasks",
415 which are bugs that cause the task to be stuck in
416 uninterruptible "D" state indefinitely.
417
418 When a hung task is detected, the kernel will print the
419 current stack trace (which you should report), but the
420 task will stay in uninterruptible state. If lockdep is
421 enabled then all held locks will also be reported. This
422 feature has negligible overhead.
423
424 config KERNEL_WQ_WATCHDOG
425 bool "Compile the kernel with detect Workqueue Stalls"
426 depends on KERNEL_DEBUG_KERNEL
427 help
428 Say Y here to enable stall detection on workqueues. If a
429 worker pool doesn't make forward progress on a pending work
430 item for over a given amount of time, 30s by default, a
431 warning message is printed along with dump of workqueue
432 state. This can be configured through kernel parameter
433 "workqueue.watchdog_thresh" and its sysfs counterpart.
434
435 config KERNEL_DEBUG_ATOMIC_SLEEP
436 bool "Compile the kernel with sleep inside atomic section checking"
437 depends on KERNEL_DEBUG_KERNEL
438 help
439 If you say Y here, various routines which may sleep will become very
440 noisy if they are called inside atomic sections: when a spinlock is
441 held, inside an rcu read side critical section, inside preempt disabled
442 sections, inside an interrupt, etc...
443
444 config KERNEL_DEBUG_VM
445 bool "Compile the kernel with debug VM"
446 depends on KERNEL_DEBUG_KERNEL
447 help
448 Enable this to turn on extended checks in the virtual-memory system
449 that may impact performance.
450
451 If unsure, say N.
452
453 config KERNEL_PRINTK_TIME
454 bool "Enable printk timestamps"
455 default y
456
457 config KERNEL_SLUB_DEBUG
458 bool
459
460 config KERNEL_SLUB_DEBUG_ON
461 bool
462
463 config KERNEL_SLABINFO
464 select KERNEL_SLUB_DEBUG
465 select KERNEL_SLUB_DEBUG_ON
466 bool "Enable /proc slab debug info"
467
468 config KERNEL_PROC_PAGE_MONITOR
469 bool "Enable /proc page monitoring"
470
471 config KERNEL_RELAY
472 bool
473
474 config KERNEL_KEXEC
475 bool "Enable kexec support"
476
477 config KERNEL_PROC_VMCORE
478 bool
479
480 config KERNEL_CRASH_DUMP
481 depends on i386 || x86_64 || arm || armeb
482 select KERNEL_KEXEC
483 select KERNEL_PROC_VMCORE
484 bool "Enable support for kexec crashdump"
485 default y
486
487 config USE_RFKILL
488 bool "Enable rfkill support"
489 default RFKILL_SUPPORT
490
491 config USE_SPARSE
492 bool "Enable sparse check during kernel build"
493 default n
494
495 config KERNEL_DEVTMPFS
496 bool "Compile the kernel with device tmpfs enabled"
497 default n
498 help
499 devtmpfs is a simple, kernel-managed /dev filesystem. The kernel creates
500 devices nodes for all registered devices to simplify boot, but leaves more
501 complex tasks to userspace (e.g. udev).
502
503 if KERNEL_DEVTMPFS
504
505 config KERNEL_DEVTMPFS_MOUNT
506 bool "Automatically mount devtmpfs after root filesystem is mounted"
507 default n
508
509 endif
510
511 config KERNEL_KEYS
512 bool "Enable kernel access key retention support"
513 default n
514
515 config KERNEL_PERSISTENT_KEYRINGS
516 bool "Enable kernel persistent keyrings"
517 depends on KERNEL_KEYS
518 default n
519
520 config KERNEL_BIG_KEYS
521 bool "Enable large payload keys on kernel keyrings"
522 depends on KERNEL_KEYS
523 default n
524
525 config KERNEL_ENCRYPTED_KEYS
526 tristate "Enable keys with encrypted payloads on kernel keyrings"
527 depends on KERNEL_KEYS
528 default n
529
530 #
531 # CGROUP support symbols
532 #
533
534 config KERNEL_CGROUPS
535 bool "Enable kernel cgroups"
536 default y if !SMALL_FLASH
537
538 if KERNEL_CGROUPS
539
540 config KERNEL_CGROUP_DEBUG
541 bool "Example debug cgroup subsystem"
542 default n
543 help
544 This option enables a simple cgroup subsystem that
545 exports useful debugging information about the cgroups
546 framework.
547
548 config KERNEL_FREEZER
549 bool
550 default y if KERNEL_CGROUP_FREEZER
551
552 config KERNEL_CGROUP_FREEZER
553 bool "Freezer cgroup subsystem"
554 default y
555 help
556 Provides a way to freeze and unfreeze all tasks in a
557 cgroup.
558
559 config KERNEL_CGROUP_DEVICE
560 bool "Device controller for cgroups"
561 default y
562 help
563 Provides a cgroup implementing whitelists for devices which
564 a process in the cgroup can mknod or open.
565
566 config KERNEL_CGROUP_PIDS
567 bool "PIDs cgroup subsystem"
568 default y
569 help
570 Provides enforcement of process number limits in the scope of a
571 cgroup.
572
573 config KERNEL_CPUSETS
574 bool "Cpuset support"
575 default y if !SMALL_FLASH
576 help
577 This option will let you create and manage CPUSETs which
578 allow dynamically partitioning a system into sets of CPUs and
579 Memory Nodes and assigning tasks to run only within those sets.
580 This is primarily useful on large SMP or NUMA systems.
581
582 config KERNEL_PROC_PID_CPUSET
583 bool "Include legacy /proc/<pid>/cpuset file"
584 default n
585 depends on KERNEL_CPUSETS
586
587 config KERNEL_CGROUP_CPUACCT
588 bool "Simple CPU accounting cgroup subsystem"
589 default y if !SMALL_FLASH
590 help
591 Provides a simple Resource Controller for monitoring the
592 total CPU consumed by the tasks in a cgroup.
593
594 config KERNEL_RESOURCE_COUNTERS
595 bool "Resource counters"
596 default y if !SMALL_FLASH
597 help
598 This option enables controller independent resource accounting
599 infrastructure that works with cgroups.
600
601 config KERNEL_MM_OWNER
602 bool
603 default y if KERNEL_MEMCG
604
605 config KERNEL_MEMCG
606 bool "Memory Resource Controller for Control Groups"
607 default y if !SMALL_FLASH
608 depends on KERNEL_RESOURCE_COUNTERS || !LINUX_3_18
609 help
610 Provides a memory resource controller that manages both anonymous
611 memory and page cache. (See Documentation/cgroups/memory.txt)
612
613 Note that setting this option increases fixed memory overhead
614 associated with each page of memory in the system. By this,
615 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
616 usage tracking struct at boot. Total amount of this is printed out
617 at boot.
618
619 Only enable when you're ok with these tradeoffs and really
620 sure you need the memory resource controller. Even when you enable
621 this, you can set "cgroup_disable=memory" at your boot option to
622 disable memory resource controller and you can avoid overheads
623 (but lose benefits of memory resource controller).
624
625 This config option also selects MM_OWNER config option, which
626 could in turn add some fork/exit overhead.
627
628 config KERNEL_MEMCG_SWAP
629 bool "Memory Resource Controller Swap Extension"
630 default n
631 depends on KERNEL_MEMCG
632 help
633 Add swap management feature to memory resource controller. When you
634 enable this, you can limit mem+swap usage per cgroup. In other words,
635 when you disable this, memory resource controller has no cares to
636 usage of swap...a process can exhaust all of the swap. This extension
637 is useful when you want to avoid exhaustion swap but this itself
638 adds more overheads and consumes memory for remembering information.
639 Especially if you use 32bit system or small memory system, please
640 be careful about enabling this. When memory resource controller
641 is disabled by boot option, this will be automatically disabled and
642 there will be no overhead from this. Even when you set this config=y,
643 if boot option "swapaccount=0" is set, swap will not be accounted.
644 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
645 size is 4096bytes, 512k per 1Gbytes of swap.
646
647 config KERNEL_MEMCG_SWAP_ENABLED
648 bool "Memory Resource Controller Swap Extension enabled by default"
649 default n
650 depends on KERNEL_MEMCG_SWAP
651 help
652 Memory Resource Controller Swap Extension comes with its price in
653 a bigger memory consumption. General purpose distribution kernels
654 which want to enable the feature but keep it disabled by default
655 and let the user enable it by swapaccount boot command line
656 parameter should have this option unselected.
657
658 Those who want to have the feature enabled by default should
659 select this option (if, for some reason, they need to disable it,
660 then swapaccount=0 does the trick).
661
662
663 config KERNEL_MEMCG_KMEM
664 bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
665 default y if !SMALL_FLASH
666 depends on KERNEL_MEMCG
667 help
668 The Kernel Memory extension for Memory Resource Controller can limit
669 the amount of memory used by kernel objects in the system. Those are
670 fundamentally different from the entities handled by the standard
671 Memory Controller, which are page-based, and can be swapped. Users of
672 the kmem extension can use it to guarantee that no group of processes
673 will ever exhaust kernel resources alone.
674
675 config KERNEL_CGROUP_PERF
676 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
677 select KERNEL_PERF_EVENTS
678 default n
679 help
680 This option extends the per-cpu mode to restrict monitoring to
681 threads which belong to the cgroup specified and run on the
682 designated cpu.
683
684 menuconfig KERNEL_CGROUP_SCHED
685 bool "Group CPU scheduler"
686 default y if !SMALL_FLASH
687 help
688 This feature lets CPU scheduler recognize task groups and control CPU
689 bandwidth allocation to such task groups. It uses cgroups to group
690 tasks.
691
692 if KERNEL_CGROUP_SCHED
693
694 config KERNEL_FAIR_GROUP_SCHED
695 bool "Group scheduling for SCHED_OTHER"
696 default y if !SMALL_FLASH
697
698 config KERNEL_CFS_BANDWIDTH
699 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
700 default n
701 depends on KERNEL_FAIR_GROUP_SCHED
702 help
703 This option allows users to define CPU bandwidth rates (limits) for
704 tasks running within the fair group scheduler. Groups with no limit
705 set are considered to be unconstrained and will run with no
706 restriction.
707 See tip/Documentation/scheduler/sched-bwc.txt for more information.
708
709 config KERNEL_RT_GROUP_SCHED
710 bool "Group scheduling for SCHED_RR/FIFO"
711 default y if !SMALL_FLASH
712 help
713 This feature lets you explicitly allocate real CPU bandwidth
714 to task groups. If enabled, it will also make it impossible to
715 schedule realtime tasks for non-root users until you allocate
716 realtime bandwidth for them.
717
718 endif
719
720 config KERNEL_BLK_CGROUP
721 bool "Block IO controller"
722 default y
723 help
724 Generic block IO controller cgroup interface. This is the common
725 cgroup interface which should be used by various IO controlling
726 policies.
727
728 Currently, CFQ IO scheduler uses it to recognize task groups and
729 control disk bandwidth allocation (proportional time slice allocation)
730 to such task groups. It is also used by bio throttling logic in
731 block layer to implement upper limit in IO rates on a device.
732
733 This option only enables generic Block IO controller infrastructure.
734 One needs to also enable actual IO controlling logic/policy. For
735 enabling proportional weight division of disk bandwidth in CFQ, set
736 CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
737 CONFIG_BLK_DEV_THROTTLING=y.
738
739 if KERNEL_BLK_CGROUP
740
741 config KERNEL_CFQ_GROUP_IOSCHED
742 bool "Proportional weight of disk bandwidth in CFQ"
743
744 config KERNEL_BLK_DEV_THROTTLING
745 bool "Enable throttling policy"
746 default y if TARGET_bcm27xx
747
748 config KERNEL_BLK_DEV_THROTTLING_LOW
749 bool "Block throttling .low limit interface support (EXPERIMENTAL)"
750 depends on KERNEL_BLK_DEV_THROTTLING
751 endif
752
753 config KERNEL_DEBUG_BLK_CGROUP
754 bool "Enable Block IO controller debugging"
755 default n
756 depends on KERNEL_BLK_CGROUP
757 help
758 Enable some debugging help. Currently it exports additional stat
759 files in a cgroup which can be useful for debugging.
760
761 config KERNEL_NET_CLS_CGROUP
762 bool "Control Group Classifier"
763 default y
764
765 config KERNEL_NETPRIO_CGROUP
766 bool "Network priority cgroup"
767 default y
768
769 endif
770
771 #
772 # Namespace support symbols
773 #
774
775 config KERNEL_NAMESPACES
776 bool "Enable kernel namespaces"
777 default y if !SMALL_FLASH
778
779 if KERNEL_NAMESPACES
780
781 config KERNEL_UTS_NS
782 bool "UTS namespace"
783 default y
784 help
785 In this namespace, tasks see different info provided
786 with the uname() system call.
787
788 config KERNEL_IPC_NS
789 bool "IPC namespace"
790 default y
791 help
792 In this namespace, tasks work with IPC ids which correspond to
793 different IPC objects in different namespaces.
794
795 config KERNEL_USER_NS
796 bool "User namespace (EXPERIMENTAL)"
797 default y
798 help
799 This allows containers, i.e. vservers, to use user namespaces
800 to provide different user info for different servers.
801
802 config KERNEL_PID_NS
803 bool "PID Namespaces"
804 default y
805 help
806 Support process id namespaces. This allows having multiple
807 processes with the same pid as long as they are in different
808 pid namespaces. This is a building block of containers.
809
810 config KERNEL_NET_NS
811 bool "Network namespace"
812 default y
813 help
814 Allow user space to create what appear to be multiple instances
815 of the network stack.
816
817 endif
818
819 config KERNEL_DEVPTS_MULTIPLE_INSTANCES
820 bool "Support multiple instances of devpts"
821 default y if !SMALL_FLASH
822 help
823 Enable support for multiple instances of devpts filesystem.
824 If you want to have isolated PTY namespaces (eg: in containers),
825 say Y here. Otherwise, say N. If enabled, each mount of devpts
826 filesystem with the '-o newinstance' option will create an
827 independent PTY namespace.
828
829 config KERNEL_POSIX_MQUEUE
830 bool "POSIX Message Queues"
831 default y if !SMALL_FLASH
832 help
833 POSIX variant of message queues is a part of IPC. In POSIX message
834 queues every message has a priority which decides about succession
835 of receiving it by a process. If you want to compile and run
836 programs written e.g. for Solaris with use of its POSIX message
837 queues (functions mq_*) say Y here.
838
839 POSIX message queues are visible as a filesystem called 'mqueue'
840 and can be mounted somewhere if you want to do filesystem
841 operations on message queues.
842
843
844 config KERNEL_SECCOMP_FILTER
845 bool
846 default y if !SMALL_FLASH
847
848 config KERNEL_SECCOMP
849 bool "Enable seccomp support"
850 depends on !(TARGET_uml)
851 select KERNEL_SECCOMP_FILTER
852 default y if !SMALL_FLASH
853 help
854 Build kernel with support for seccomp.
855
856 #
857 # IPv4 configuration
858 #
859
860 config KERNEL_IP_MROUTE
861 bool "Enable IPv4 multicast routing"
862 default y
863 help
864 Multicast routing requires a multicast routing daemon in
865 addition to kernel support.
866
867 #
868 # IPv6 configuration
869 #
870
871 config KERNEL_IPV6
872 def_bool IPV6
873
874 if KERNEL_IPV6
875
876 config KERNEL_IPV6_MULTIPLE_TABLES
877 def_bool y
878
879 config KERNEL_IPV6_SUBTREES
880 def_bool y
881
882 config KERNEL_IPV6_MROUTE
883 bool "Enable IPv6 multicast routing"
884 default y
885 help
886 Multicast routing requires a multicast routing daemon in
887 addition to kernel support.
888
889 config KERNEL_IPV6_PIMSM_V2
890 def_bool n
891
892 endif
893
894 #
895 # NFS related symbols
896 #
897 config KERNEL_IP_PNP
898 bool "Compile the kernel with rootfs on NFS"
899 help
900 If you want to make your kernel boot off a NFS server as root
901 filesystem, select Y here.
902
903 if KERNEL_IP_PNP
904
905 config KERNEL_IP_PNP_DHCP
906 def_bool y
907
908 config KERNEL_IP_PNP_BOOTP
909 def_bool n
910
911 config KERNEL_IP_PNP_RARP
912 def_bool n
913
914 config KERNEL_NFS_FS
915 def_bool y
916
917 config KERNEL_NFS_V2
918 def_bool y
919
920 config KERNEL_NFS_V3
921 def_bool y
922
923 config KERNEL_ROOT_NFS
924 def_bool y
925
926 endif
927
928 menu "Filesystem ACL and attr support options"
929 config USE_FS_ACL_ATTR
930 bool "Use filesystem ACL and attr support by default"
931 default n
932 help
933 Make using ACLs (e.g. POSIX ACL, NFSv4 ACL) the default
934 for kernel and packages, except tmpfs, flash filesystems,
935 and old NFS. Also enable userspace extended attribute support
936 by default. (OpenWrt already has an expection it will be
937 present in the kernel).
938
939 config KERNEL_FS_POSIX_ACL
940 bool "Enable POSIX ACL support"
941 default y if USE_FS_ACL_ATTR
942
943 config KERNEL_BTRFS_FS_POSIX_ACL
944 bool "Enable POSIX ACL for BtrFS Filesystems"
945 select KERNEL_FS_POSIX_ACL
946 default y if USE_FS_ACL_ATTR
947
948 config KERNEL_EXT4_FS_POSIX_ACL
949 bool "Enable POSIX ACL for Ext4 Filesystems"
950 select KERNEL_FS_POSIX_ACL
951 default y if USE_FS_ACL_ATTR
952
953 config KERNEL_F2FS_FS_POSIX_ACL
954 bool "Enable POSIX ACL for F2FS Filesystems"
955 select KERNEL_FS_POSIX_ACL
956 default n
957
958 config KERNEL_JFFS2_FS_POSIX_ACL
959 bool "Enable POSIX ACL for JFFS2 Filesystems"
960 select KERNEL_FS_POSIX_ACL
961 default n
962
963 config KERNEL_TMPFS_POSIX_ACL
964 bool "Enable POSIX ACL for TMPFS Filesystems"
965 select KERNEL_FS_POSIX_ACL
966 default n
967
968 config KERNEL_CIFS_ACL
969 bool "Enable CIFS ACLs"
970 select KERNEL_FS_POSIX_ACL
971 default y if USE_FS_ACL_ATTR
972
973 config KERNEL_HFS_FS_POSIX_ACL
974 bool "Enable POSIX ACL for HFS Filesystems"
975 select KERNEL_FS_POSIX_ACL
976 default y if USE_FS_ACL_ATTR
977
978 config KERNEL_HFSPLUS_FS_POSIX_ACL
979 bool "Enable POSIX ACL for HFS+ Filesystems"
980 select KERNEL_FS_POSIX_ACL
981 default y if USE_FS_ACL_ATTR
982
983 config KERNEL_NFS_ACL_SUPPORT
984 bool "Enable ACLs for NFS"
985 default y if USE_FS_ACL_ATTR
986
987 config KERNEL_NFS_V3_ACL_SUPPORT
988 bool "Enable ACLs for NFSv3"
989 default n
990
991 config KERNEL_NFSD_V2_ACL_SUPPORT
992 bool "Enable ACLs for NFSDv2"
993 default n
994
995 config KERNEL_NFSD_V3_ACL_SUPPORT
996 bool "Enable ACLs for NFSDv3"
997 default n
998
999 config KERNEL_REISER_FS_POSIX_ACL
1000 bool "Enable POSIX ACLs for ReiserFS"
1001 select KERNEL_FS_POSIX_ACL
1002 default y if USE_FS_ACL_ATTR
1003
1004 config KERNEL_XFS_POSIX_ACL
1005 bool "Enable POSIX ACLs for XFS"
1006 select KERNEL_FS_POSIX_ACL
1007 default y if USE_FS_ACL_ATTR
1008
1009 config KERNEL_JFS_POSIX_ACL
1010 bool "Enable POSIX ACLs for JFS"
1011 select KERNEL_FS_POSIX_ACL
1012 default y if USE_FS_ACL_ATTR
1013
1014 endmenu
1015
1016 config KERNEL_DEVMEM
1017 bool "/dev/mem virtual device support"
1018 help
1019 Say Y here if you want to support the /dev/mem device.
1020 The /dev/mem device is used to access areas of physical
1021 memory.
1022
1023 config KERNEL_DEVKMEM
1024 bool "/dev/kmem virtual device support"
1025 help
1026 Say Y here if you want to support the /dev/kmem device. The
1027 /dev/kmem device is rarely used, but can be used for certain
1028 kind of kernel debugging operations.
1029
1030 config KERNEL_SQUASHFS_FRAGMENT_CACHE_SIZE
1031 int "Number of squashfs fragments cached"
1032 default 2 if (SMALL_FLASH && !LOW_MEMORY_FOOTPRINT)
1033 default 3
1034
1035 #
1036 # compile optimiziation setting
1037 #
1038 choice
1039 prompt "Compiler optimization level"
1040 default KERNEL_CC_OPTIMIZE_FOR_SIZE if SMALL_FLASH
1041
1042 config KERNEL_CC_OPTIMIZE_FOR_PERFORMANCE
1043 bool "Optimize for performance"
1044 help
1045 This is the default optimization level for the kernel, building
1046 with the "-O2" compiler flag for best performance and most
1047 helpful compile-time warnings.
1048
1049 config KERNEL_CC_OPTIMIZE_FOR_SIZE
1050 bool "Optimize for size"
1051 help
1052 Enabling this option will pass "-Os" instead of "-O2" to
1053 your compiler resulting in a smaller kernel.
1054
1055 endchoice