1 # Copyright (C) 2006-2014 OpenWrt.org
3 # This is free software, licensed under the GNU General Public License v2.
4 # See /LICENSE for more information.
8 bool "Enable support for printk"
11 config KERNEL_CRASHLOG
13 depends on !(arm || powerpc || sparc || TARGET_uml)
17 bool "Support for paging of anonymous memory (swap)"
20 config KERNEL_DEBUG_FS
21 bool "Compile the kernel with debug filesystem enabled"
24 debugfs is a virtual file system that kernel developers use to put
25 debugging files into. Enable this option to be able to read and
26 write to these files. Many common debugging facilities, such as
27 ftrace, require the existence of debugfs.
29 config KERNEL_PERF_EVENTS
33 config KERNEL_PROFILING
34 bool "Compile the kernel with profiling enabled"
36 select KERNEL_PERF_EVENTS
38 Enable the extended profiling support mechanisms used by profilers such
41 config KERNEL_KALLSYMS
42 bool "Compile the kernel with symbol table information"
45 This will give you more information in stack traces from kernel oopses.
48 bool "Compile the kernel with tracing support"
51 config KERNEL_FTRACE_SYSCALLS
52 bool "Trace system calls"
53 depends on KERNEL_FTRACE
56 config KERNEL_ENABLE_DEFAULT_TRACERS
57 bool "Trace process context switches and events"
58 depends on KERNEL_FTRACE
61 config KERNEL_DEBUG_KERNEL
65 config KERNEL_DEBUG_INFO
66 bool "Compile the kernel with debug information"
68 select KERNEL_DEBUG_KERNEL
70 This will compile your kernel and modules with debug information.
72 config KERNEL_DEBUG_LL_UART_NONE
77 config KERNEL_DEBUG_LL
81 select KERNEL_DEBUG_LL_UART_NONE
83 ARM low level debugging.
85 config KERNEL_DYNAMIC_DEBUG
86 bool "Compile the kernel with dynamic printk"
87 select KERNEL_DEBUG_FS
90 Compiles debug level messages into the kernel, which would not
91 otherwise be available at runtime. These messages can then be
92 enabled/disabled based on various levels of scope - per source file,
93 function, module, format string, and line number. This mechanism
94 implicitly compiles in all pr_debug() and dev_dbg() calls, which
95 enlarges the kernel text size by about 2%.
97 config KERNEL_EARLY_PRINTK
98 bool "Compile the kernel with early printk"
99 default y if TARGET_bcm53xx
102 select KERNEL_DEBUG_KERNEL
103 select KERNEL_DEBUG_LL if arm
105 Compile the kernel with early printk support. This is only useful for
106 debugging purposes to send messages over the serial console in early boot.
107 Enable this to debug early boot problems.
110 bool "Compile the kernel with asynchronous IO support"
113 config KERNEL_DIRECT_IO
114 bool "Compile the kernel with direct IO support"
117 config KERNEL_MAGIC_SYSRQ
118 bool "Compile the kernel with SysRq support"
121 config KERNEL_COREDUMP
124 config KERNEL_ELF_CORE
125 bool "Enable process core dump support"
126 select KERNEL_COREDUMP
129 config KERNEL_PROVE_LOCKING
130 bool "Enable kernel lock checking"
131 select KERNEL_DEBUG_KERNEL
134 config KERNEL_PRINTK_TIME
135 bool "Enable printk timestamps"
138 config KERNEL_SLUB_DEBUG
141 config KERNEL_SLUB_DEBUG_ON
144 config KERNEL_SLABINFO
145 select KERNEL_SLUB_DEBUG
146 select KERNEL_SLUB_DEBUG_ON
147 bool "Enable /proc slab debug info"
149 config KERNEL_PROC_PAGE_MONITOR
150 bool "Enable /proc page monitoring"
156 bool "Enable kexec support"
159 bool "Enable rfkill support"
160 default RFKILL_SUPPORT
163 bool "Enable sparse check during kernel build"
167 # CGROUP support symbols
170 config KERNEL_CGROUPS
171 bool "Enable kernel cgroups"
176 config KERNEL_CGROUP_DEBUG
177 bool "Example debug cgroup subsystem"
180 This option enables a simple cgroup subsystem that
181 exports useful debugging information about the cgroups
184 config KERNEL_FREEZER
186 default y if KERNEL_CGROUP_FREEZER
188 config KERNEL_CGROUP_FREEZER
189 bool "Freezer cgroup subsystem"
192 Provides a way to freeze and unfreeze all tasks in a
195 config KERNEL_CGROUP_DEVICE
196 bool "Device controller for cgroups"
199 Provides a cgroup implementing whitelists for devices which
200 a process in the cgroup can mknod or open.
202 config KERNEL_CPUSETS
203 bool "Cpuset support"
206 This option will let you create and manage CPUSETs which
207 allow dynamically partitioning a system into sets of CPUs and
208 Memory Nodes and assigning tasks to run only within those sets.
209 This is primarily useful on large SMP or NUMA systems.
211 config KERNEL_PROC_PID_CPUSET
212 bool "Include legacy /proc/<pid>/cpuset file"
214 depends on KERNEL_CPUSETS
216 config KERNEL_CGROUP_CPUACCT
217 bool "Simple CPU accounting cgroup subsystem"
220 Provides a simple Resource Controller for monitoring the
221 total CPU consumed by the tasks in a cgroup.
223 config KERNEL_RESOURCE_COUNTERS
224 bool "Resource counters"
227 This option enables controller independent resource accounting
228 infrastructure that works with cgroups.
230 config KERNEL_MM_OWNER
232 default y if KERNEL_MEMCG
235 bool "Memory Resource Controller for Control Groups"
237 depends on KERNEL_RESOURCE_COUNTERS
239 Provides a memory resource controller that manages both anonymous
240 memory and page cache. (See Documentation/cgroups/memory.txt)
242 Note that setting this option increases fixed memory overhead
243 associated with each page of memory in the system. By this,
244 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
245 usage tracking struct at boot. Total amount of this is printed out
248 Only enable when you're ok with these tradeoffs and really
249 sure you need the memory resource controller. Even when you enable
250 this, you can set "cgroup_disable=memory" at your boot option to
251 disable memory resource controller and you can avoid overheads
252 (but lose benefits of memory resource controller).
254 This config option also selects MM_OWNER config option, which
255 could in turn add some fork/exit overhead.
257 config KERNEL_MEMCG_SWAP
258 bool "Memory Resource Controller Swap Extension"
260 depends on KERNEL_MEMCG
262 Add swap management feature to memory resource controller. When you
263 enable this, you can limit mem+swap usage per cgroup. In other words,
264 when you disable this, memory resource controller has no cares to
265 usage of swap...a process can exhaust all of the swap. This extension
266 is useful when you want to avoid exhaustion swap but this itself
267 adds more overheads and consumes memory for remembering information.
268 Especially if you use 32bit system or small memory system, please
269 be careful about enabling this. When memory resource controller
270 is disabled by boot option, this will be automatically disabled and
271 there will be no overhead from this. Even when you set this config=y,
272 if boot option "swapaccount=0" is set, swap will not be accounted.
273 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
274 size is 4096bytes, 512k per 1Gbytes of swap.
276 config KERNEL_MEMCG_SWAP_ENABLED
277 bool "Memory Resource Controller Swap Extension enabled by default"
279 depends on KERNEL_MEMCG_SWAP
281 Memory Resource Controller Swap Extension comes with its price in
282 a bigger memory consumption. General purpose distribution kernels
283 which want to enable the feature but keep it disabled by default
284 and let the user enable it by swapaccount boot command line
285 parameter should have this option unselected.
287 Those who want to have the feature enabled by default should
288 select this option (if, for some reason, they need to disable it,
289 then swapaccount=0 does the trick).
292 config KERNEL_MEMCG_KMEM
293 bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
295 depends on KERNEL_MEMCG
297 The Kernel Memory extension for Memory Resource Controller can limit
298 the amount of memory used by kernel objects in the system. Those are
299 fundamentally different from the entities handled by the standard
300 Memory Controller, which are page-based, and can be swapped. Users of
301 the kmem extension can use it to guarantee that no group of processes
302 will ever exhaust kernel resources alone.
304 config KERNEL_CGROUP_PERF
305 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
306 select KERNEL_PERF_EVENTS
309 This option extends the per-cpu mode to restrict monitoring to
310 threads which belong to the cgroup specified and run on the
313 menuconfig KERNEL_CGROUP_SCHED
314 bool "Group CPU scheduler"
317 This feature lets CPU scheduler recognize task groups and control CPU
318 bandwidth allocation to such task groups. It uses cgroups to group
321 if KERNEL_CGROUP_SCHED
323 config KERNEL_FAIR_GROUP_SCHED
324 bool "Group scheduling for SCHED_OTHER"
327 config KERNEL_CFS_BANDWIDTH
328 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
330 depends on KERNEL_FAIR_GROUP_SCHED
332 This option allows users to define CPU bandwidth rates (limits) for
333 tasks running within the fair group scheduler. Groups with no limit
334 set are considered to be unconstrained and will run with no
336 See tip/Documentation/scheduler/sched-bwc.txt for more information.
338 config KERNEL_RT_GROUP_SCHED
339 bool "Group scheduling for SCHED_RR/FIFO"
342 This feature lets you explicitly allocate real CPU bandwidth
343 to task groups. If enabled, it will also make it impossible to
344 schedule realtime tasks for non-root users until you allocate
345 realtime bandwidth for them.
349 config KERNEL_BLK_CGROUP
350 bool "Block IO controller"
353 Generic block IO controller cgroup interface. This is the common
354 cgroup interface which should be used by various IO controlling
357 Currently, CFQ IO scheduler uses it to recognize task groups and
358 control disk bandwidth allocation (proportional time slice allocation)
359 to such task groups. It is also used by bio throttling logic in
360 block layer to implement upper limit in IO rates on a device.
362 This option only enables generic Block IO controller infrastructure.
363 One needs to also enable actual IO controlling logic/policy. For
364 enabling proportional weight division of disk bandwidth in CFQ, set
365 CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
366 CONFIG_BLK_DEV_THROTTLING=y.
368 config KERNEL_DEBUG_BLK_CGROUP
369 bool "Enable Block IO controller debugging"
371 depends on KERNEL_BLK_CGROUP
373 Enable some debugging help. Currently it exports additional stat
374 files in a cgroup which can be useful for debugging.
376 config KERNEL_NET_CLS_CGROUP
377 bool "Control Group Classifier"
380 config KERNEL_NETPRIO_CGROUP
381 bool "Network priority cgroup"
387 # Namespace support symbols
390 config KERNEL_NAMESPACES
391 bool "Enable kernel namespaces"
400 In this namespace, tasks see different info provided
401 with the uname() system call.
407 In this namespace, tasks work with IPC ids which correspond to
408 different IPC objects in different namespaces.
410 config KERNEL_USER_NS
411 bool "User namespace (EXPERIMENTAL)"
414 This allows containers, i.e. vservers, to use user namespaces
415 to provide different user info for different servers.
418 bool "PID Namespaces"
421 Support process id namespaces. This allows having multiple
422 processes with the same pid as long as they are in different
423 pid namespaces. This is a building block of containers.
426 bool "Network namespace"
429 Allow user space to create what appear to be multiple instances
430 of the network stack.
435 # LXC related symbols
438 config KERNEL_LXC_MISC
439 bool "Enable miscellaneous LXC related options"
444 config KERNEL_DEVPTS_MULTIPLE_INSTANCES
445 bool "Support multiple instances of devpts"
448 Enable support for multiple instances of devpts filesystem.
449 If you want to have isolated PTY namespaces (eg: in containers),
450 say Y here. Otherwise, say N. If enabled, each mount of devpts
451 filesystem with the '-o newinstance' option will create an
452 independent PTY namespace.
454 config KERNEL_POSIX_MQUEUE
455 bool "POSIX Message Queues"
458 POSIX variant of message queues is a part of IPC. In POSIX message
459 queues every message has a priority which decides about succession
460 of receiving it by a process. If you want to compile and run
461 programs written e.g. for Solaris with use of its POSIX message
462 queues (functions mq_*) say Y here.
464 POSIX message queues are visible as a filesystem called 'mqueue'
465 and can be mounted somewhere if you want to do filesystem
466 operations on message queues.
470 config KERNEL_SECCOMP
471 bool "Enable seccomp support"
472 depends on !(TARGET_uml || TARGET_avr32)
475 Build kernel with support for seccomp.
477 config KERNEL_SECCOMP_FILTER
478 bool "Enable seccomp filter support"
479 depends on KERNEL_SECCOMP
482 Build kernel with support for seccomp BPF programs.