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"
49 depends on !TARGET_uml
52 config KERNEL_FTRACE_SYSCALLS
53 bool "Trace system calls"
54 depends on KERNEL_FTRACE
57 config KERNEL_ENABLE_DEFAULT_TRACERS
58 bool "Trace process context switches and events"
59 depends on KERNEL_FTRACE
62 config KERNEL_FUNCTION_TRACER
63 bool "Function tracer"
64 depends on KERNEL_FTRACE
67 config KERNEL_FUNCTION_GRAPH_TRACER
68 bool "Function graph tracer"
69 depends on KERNEL_FUNCTION_TRACER
72 config KERNEL_DYNAMIC_FTRACE
73 bool "Enable/disable function tracing dynamically"
74 depends on KERNEL_FUNCTION_TRACER
77 config KERNEL_FUNCTION_PROFILER
78 bool "Function profiler"
79 depends on KERNEL_FUNCTION_TRACER
82 config KERNEL_DEBUG_KERNEL
86 config KERNEL_DEBUG_INFO
87 bool "Compile the kernel with debug information"
89 select KERNEL_DEBUG_KERNEL
91 This will compile your kernel and modules with debug information.
93 config KERNEL_DEBUG_LL_UART_NONE
98 config KERNEL_DEBUG_LL
102 select KERNEL_DEBUG_LL_UART_NONE
104 ARM low level debugging.
106 config KERNEL_DYNAMIC_DEBUG
107 bool "Compile the kernel with dynamic printk"
108 select KERNEL_DEBUG_FS
111 Compiles debug level messages into the kernel, which would not
112 otherwise be available at runtime. These messages can then be
113 enabled/disabled based on various levels of scope - per source file,
114 function, module, format string, and line number. This mechanism
115 implicitly compiles in all pr_debug() and dev_dbg() calls, which
116 enlarges the kernel text size by about 2%.
118 config KERNEL_EARLY_PRINTK
119 bool "Compile the kernel with early printk"
120 default y if TARGET_bcm53xx
123 select KERNEL_DEBUG_KERNEL
124 select KERNEL_DEBUG_LL if arm
126 Compile the kernel with early printk support. This is only useful for
127 debugging purposes to send messages over the serial console in early boot.
128 Enable this to debug early boot problems.
131 bool "Compile the kernel with asynchronous IO support"
134 config KERNEL_DIRECT_IO
135 bool "Compile the kernel with direct IO support"
138 config KERNEL_FHANDLE
139 bool "Compile the kernel with support for fhandle syscalls"
142 config KERNEL_FANOTIFY
143 bool "Compile the kernel with modern file notification support"
146 config KERNEL_BLK_DEV_BSG
147 bool "Compile the kernel with SCSI generic v4 support for any block device"
150 config KERNEL_MAGIC_SYSRQ
151 bool "Compile the kernel with SysRq support"
154 config KERNEL_COREDUMP
157 config KERNEL_ELF_CORE
158 bool "Enable process core dump support"
159 select KERNEL_COREDUMP
162 config KERNEL_PROVE_LOCKING
163 bool "Enable kernel lock checking"
164 select KERNEL_DEBUG_KERNEL
167 config KERNEL_PRINTK_TIME
168 bool "Enable printk timestamps"
171 config KERNEL_SLUB_DEBUG
174 config KERNEL_SLUB_DEBUG_ON
177 config KERNEL_SLABINFO
178 select KERNEL_SLUB_DEBUG
179 select KERNEL_SLUB_DEBUG_ON
180 bool "Enable /proc slab debug info"
182 config KERNEL_PROC_PAGE_MONITOR
183 bool "Enable /proc page monitoring"
189 bool "Enable kexec support"
192 bool "Enable rfkill support"
193 default RFKILL_SUPPORT
196 bool "Enable sparse check during kernel build"
199 config KERNEL_DEVTMPFS
200 bool "Compile the kernel with device tmpfs enabled"
203 devtmpfs is a simple, kernel-managed /dev filesystem. The kernel creates
204 devices nodes for all registered devices ti simplify boot, but leaves more
205 complex tasks to userspace (e.g. udev).
209 config KERNEL_DEVTMPFS_MOUNT
210 bool "Automatically mount devtmpfs after root filesystem is mounted"
216 # CGROUP support symbols
219 config KERNEL_CGROUPS
220 bool "Enable kernel cgroups"
225 config KERNEL_CGROUP_DEBUG
226 bool "Example debug cgroup subsystem"
229 This option enables a simple cgroup subsystem that
230 exports useful debugging information about the cgroups
233 config KERNEL_FREEZER
235 default y if KERNEL_CGROUP_FREEZER
237 config KERNEL_CGROUP_FREEZER
238 bool "Freezer cgroup subsystem"
241 Provides a way to freeze and unfreeze all tasks in a
244 config KERNEL_CGROUP_DEVICE
245 bool "Device controller for cgroups"
248 Provides a cgroup implementing whitelists for devices which
249 a process in the cgroup can mknod or open.
251 config KERNEL_CPUSETS
252 bool "Cpuset support"
255 This option will let you create and manage CPUSETs which
256 allow dynamically partitioning a system into sets of CPUs and
257 Memory Nodes and assigning tasks to run only within those sets.
258 This is primarily useful on large SMP or NUMA systems.
260 config KERNEL_PROC_PID_CPUSET
261 bool "Include legacy /proc/<pid>/cpuset file"
263 depends on KERNEL_CPUSETS
265 config KERNEL_CGROUP_CPUACCT
266 bool "Simple CPU accounting cgroup subsystem"
269 Provides a simple Resource Controller for monitoring the
270 total CPU consumed by the tasks in a cgroup.
272 config KERNEL_RESOURCE_COUNTERS
273 bool "Resource counters"
276 This option enables controller independent resource accounting
277 infrastructure that works with cgroups.
279 config KERNEL_MM_OWNER
281 default y if KERNEL_MEMCG
284 bool "Memory Resource Controller for Control Groups"
286 depends on KERNEL_RESOURCE_COUNTERS
288 Provides a memory resource controller that manages both anonymous
289 memory and page cache. (See Documentation/cgroups/memory.txt)
291 Note that setting this option increases fixed memory overhead
292 associated with each page of memory in the system. By this,
293 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
294 usage tracking struct at boot. Total amount of this is printed out
297 Only enable when you're ok with these tradeoffs and really
298 sure you need the memory resource controller. Even when you enable
299 this, you can set "cgroup_disable=memory" at your boot option to
300 disable memory resource controller and you can avoid overheads
301 (but lose benefits of memory resource controller).
303 This config option also selects MM_OWNER config option, which
304 could in turn add some fork/exit overhead.
306 config KERNEL_MEMCG_SWAP
307 bool "Memory Resource Controller Swap Extension"
309 depends on KERNEL_MEMCG
311 Add swap management feature to memory resource controller. When you
312 enable this, you can limit mem+swap usage per cgroup. In other words,
313 when you disable this, memory resource controller has no cares to
314 usage of swap...a process can exhaust all of the swap. This extension
315 is useful when you want to avoid exhaustion swap but this itself
316 adds more overheads and consumes memory for remembering information.
317 Especially if you use 32bit system or small memory system, please
318 be careful about enabling this. When memory resource controller
319 is disabled by boot option, this will be automatically disabled and
320 there will be no overhead from this. Even when you set this config=y,
321 if boot option "swapaccount=0" is set, swap will not be accounted.
322 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
323 size is 4096bytes, 512k per 1Gbytes of swap.
325 config KERNEL_MEMCG_SWAP_ENABLED
326 bool "Memory Resource Controller Swap Extension enabled by default"
328 depends on KERNEL_MEMCG_SWAP
330 Memory Resource Controller Swap Extension comes with its price in
331 a bigger memory consumption. General purpose distribution kernels
332 which want to enable the feature but keep it disabled by default
333 and let the user enable it by swapaccount boot command line
334 parameter should have this option unselected.
336 Those who want to have the feature enabled by default should
337 select this option (if, for some reason, they need to disable it,
338 then swapaccount=0 does the trick).
341 config KERNEL_MEMCG_KMEM
342 bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
344 depends on KERNEL_MEMCG
346 The Kernel Memory extension for Memory Resource Controller can limit
347 the amount of memory used by kernel objects in the system. Those are
348 fundamentally different from the entities handled by the standard
349 Memory Controller, which are page-based, and can be swapped. Users of
350 the kmem extension can use it to guarantee that no group of processes
351 will ever exhaust kernel resources alone.
353 config KERNEL_CGROUP_PERF
354 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
355 select KERNEL_PERF_EVENTS
358 This option extends the per-cpu mode to restrict monitoring to
359 threads which belong to the cgroup specified and run on the
362 menuconfig KERNEL_CGROUP_SCHED
363 bool "Group CPU scheduler"
366 This feature lets CPU scheduler recognize task groups and control CPU
367 bandwidth allocation to such task groups. It uses cgroups to group
370 if KERNEL_CGROUP_SCHED
372 config KERNEL_FAIR_GROUP_SCHED
373 bool "Group scheduling for SCHED_OTHER"
376 config KERNEL_CFS_BANDWIDTH
377 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
379 depends on KERNEL_FAIR_GROUP_SCHED
381 This option allows users to define CPU bandwidth rates (limits) for
382 tasks running within the fair group scheduler. Groups with no limit
383 set are considered to be unconstrained and will run with no
385 See tip/Documentation/scheduler/sched-bwc.txt for more information.
387 config KERNEL_RT_GROUP_SCHED
388 bool "Group scheduling for SCHED_RR/FIFO"
391 This feature lets you explicitly allocate real CPU bandwidth
392 to task groups. If enabled, it will also make it impossible to
393 schedule realtime tasks for non-root users until you allocate
394 realtime bandwidth for them.
398 config KERNEL_BLK_CGROUP
399 bool "Block IO controller"
402 Generic block IO controller cgroup interface. This is the common
403 cgroup interface which should be used by various IO controlling
406 Currently, CFQ IO scheduler uses it to recognize task groups and
407 control disk bandwidth allocation (proportional time slice allocation)
408 to such task groups. It is also used by bio throttling logic in
409 block layer to implement upper limit in IO rates on a device.
411 This option only enables generic Block IO controller infrastructure.
412 One needs to also enable actual IO controlling logic/policy. For
413 enabling proportional weight division of disk bandwidth in CFQ, set
414 CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
415 CONFIG_BLK_DEV_THROTTLING=y.
417 config KERNEL_DEBUG_BLK_CGROUP
418 bool "Enable Block IO controller debugging"
420 depends on KERNEL_BLK_CGROUP
422 Enable some debugging help. Currently it exports additional stat
423 files in a cgroup which can be useful for debugging.
425 config KERNEL_NET_CLS_CGROUP
426 bool "Control Group Classifier"
429 config KERNEL_NETPRIO_CGROUP
430 bool "Network priority cgroup"
436 # Namespace support symbols
439 config KERNEL_NAMESPACES
440 bool "Enable kernel namespaces"
449 In this namespace, tasks see different info provided
450 with the uname() system call.
456 In this namespace, tasks work with IPC ids which correspond to
457 different IPC objects in different namespaces.
459 config KERNEL_USER_NS
460 bool "User namespace (EXPERIMENTAL)"
463 This allows containers, i.e. vservers, to use user namespaces
464 to provide different user info for different servers.
467 bool "PID Namespaces"
470 Support process id namespaces. This allows having multiple
471 processes with the same pid as long as they are in different
472 pid namespaces. This is a building block of containers.
475 bool "Network namespace"
478 Allow user space to create what appear to be multiple instances
479 of the network stack.
484 # LXC related symbols
487 config KERNEL_LXC_MISC
488 bool "Enable miscellaneous LXC related options"
493 config KERNEL_DEVPTS_MULTIPLE_INSTANCES
494 bool "Support multiple instances of devpts"
497 Enable support for multiple instances of devpts filesystem.
498 If you want to have isolated PTY namespaces (eg: in containers),
499 say Y here. Otherwise, say N. If enabled, each mount of devpts
500 filesystem with the '-o newinstance' option will create an
501 independent PTY namespace.
503 config KERNEL_POSIX_MQUEUE
504 bool "POSIX Message Queues"
507 POSIX variant of message queues is a part of IPC. In POSIX message
508 queues every message has a priority which decides about succession
509 of receiving it by a process. If you want to compile and run
510 programs written e.g. for Solaris with use of its POSIX message
511 queues (functions mq_*) say Y here.
513 POSIX message queues are visible as a filesystem called 'mqueue'
514 and can be mounted somewhere if you want to do filesystem
515 operations on message queues.
519 config KERNEL_SECCOMP
520 bool "Enable seccomp support"
521 depends on !(TARGET_uml)
524 Build kernel with support for seccomp.
526 config KERNEL_SECCOMP_FILTER
527 bool "Enable seccomp filter support"
528 depends on KERNEL_SECCOMP
531 Build kernel with support for seccomp BPF programs.