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.
7 config KERNEL_BUILD_USER
8 string "Custom Kernel Build User Name"
11 Sets the Kernel build user string, which for example will be returned
12 by 'uname -a' on running systems.
13 If not set, uses system user at build time.
15 config KERNEL_BUILD_DOMAIN
16 string "Custom Kernel Build Domain Name"
19 Sets the Kernel build domain string, which for example will be
20 returned by 'uname -a' on running systems.
21 If not set, uses system hostname at build time.
24 bool "Enable support for printk"
27 config KERNEL_CRASHLOG
29 depends on !(arm || powerpc || sparc || TARGET_uml)
33 bool "Support for paging of anonymous memory (swap)"
36 config KERNEL_DEBUG_FS
37 bool "Compile the kernel with debug filesystem enabled"
40 debugfs is a virtual file system that kernel developers use to put
41 debugging files into. Enable this option to be able to read and
42 write to these files. Many common debugging facilities, such as
43 ftrace, require the existence of debugfs.
48 depends on (arm || arm64)
50 config KERNEL_PERF_EVENTS
53 select KERNEL_ARM_PMU if (arm || arm64)
55 config KERNEL_PROFILING
56 bool "Compile the kernel with profiling enabled"
58 select KERNEL_PERF_EVENTS
60 Enable the extended profiling support mechanisms used by profilers such
63 config KERNEL_KALLSYMS
64 bool "Compile the kernel with symbol table information"
67 This will give you more information in stack traces from kernel oopses.
70 bool "Compile the kernel with tracing support"
71 depends on !TARGET_uml
74 config KERNEL_FTRACE_SYSCALLS
75 bool "Trace system calls"
76 depends on KERNEL_FTRACE
79 config KERNEL_ENABLE_DEFAULT_TRACERS
80 bool "Trace process context switches and events"
81 depends on KERNEL_FTRACE
84 config KERNEL_FUNCTION_TRACER
85 bool "Function tracer"
86 depends on KERNEL_FTRACE
89 config KERNEL_FUNCTION_GRAPH_TRACER
90 bool "Function graph tracer"
91 depends on KERNEL_FUNCTION_TRACER
94 config KERNEL_DYNAMIC_FTRACE
95 bool "Enable/disable function tracing dynamically"
96 depends on KERNEL_FUNCTION_TRACER
99 config KERNEL_FUNCTION_PROFILER
100 bool "Function profiler"
101 depends on KERNEL_FUNCTION_TRACER
104 config KERNEL_DEBUG_KERNEL
108 config KERNEL_DEBUG_INFO
109 bool "Compile the kernel with debug information"
111 select KERNEL_DEBUG_KERNEL
113 This will compile your kernel and modules with debug information.
115 config KERNEL_DEBUG_LL_UART_NONE
120 config KERNEL_DEBUG_LL
124 select KERNEL_DEBUG_LL_UART_NONE
126 ARM low level debugging.
128 config KERNEL_DYNAMIC_DEBUG
129 bool "Compile the kernel with dynamic printk"
130 select KERNEL_DEBUG_FS
133 Compiles debug level messages into the kernel, which would not
134 otherwise be available at runtime. These messages can then be
135 enabled/disabled based on various levels of scope - per source file,
136 function, module, format string, and line number. This mechanism
137 implicitly compiles in all pr_debug() and dev_dbg() calls, which
138 enlarges the kernel text size by about 2%.
140 config KERNEL_EARLY_PRINTK
141 bool "Compile the kernel with early printk"
142 default y if TARGET_bcm53xx
145 select KERNEL_DEBUG_KERNEL
146 select KERNEL_DEBUG_LL if arm
148 Compile the kernel with early printk support. This is only useful for
149 debugging purposes to send messages over the serial console in early boot.
150 Enable this to debug early boot problems.
152 config KERNEL_KPROBES
153 bool "Compile the kernel with kprobes support"
156 select KERNEL_PERF_EVENTS
158 Compiles the kernel with KPROBES support, which allows you to trap
159 at almost any kernel address and execute a callback function.
160 register_kprobe() establishes a probepoint and specifies the
161 callback. Kprobes is useful for kernel debugging, non-intrusive
162 instrumentation and testing.
163 If in doubt, say "N".
165 config KERNEL_KPROBE_EVENT
167 default y if KERNEL_KPROBES
170 bool "Compile the kernel with asynchronous IO support"
173 config KERNEL_DIRECT_IO
174 bool "Compile the kernel with direct IO support"
177 config KERNEL_FHANDLE
178 bool "Compile the kernel with support for fhandle syscalls"
181 config KERNEL_FANOTIFY
182 bool "Compile the kernel with modern file notification support"
185 config KERNEL_BLK_DEV_BSG
186 bool "Compile the kernel with SCSI generic v4 support for any block device"
189 config KERNEL_MAGIC_SYSRQ
190 bool "Compile the kernel with SysRq support"
193 config KERNEL_COREDUMP
196 config KERNEL_ELF_CORE
197 bool "Enable process core dump support"
198 select KERNEL_COREDUMP
201 config KERNEL_PROVE_LOCKING
202 bool "Enable kernel lock checking"
203 select KERNEL_DEBUG_KERNEL
206 config KERNEL_PRINTK_TIME
207 bool "Enable printk timestamps"
210 config KERNEL_SLUB_DEBUG
213 config KERNEL_SLUB_DEBUG_ON
216 config KERNEL_SLABINFO
217 select KERNEL_SLUB_DEBUG
218 select KERNEL_SLUB_DEBUG_ON
219 bool "Enable /proc slab debug info"
221 config KERNEL_PROC_PAGE_MONITOR
222 bool "Enable /proc page monitoring"
228 bool "Enable kexec support"
231 bool "Enable rfkill support"
232 default RFKILL_SUPPORT
235 bool "Enable sparse check during kernel build"
238 config KERNEL_DEVTMPFS
239 bool "Compile the kernel with device tmpfs enabled"
242 devtmpfs is a simple, kernel-managed /dev filesystem. The kernel creates
243 devices nodes for all registered devices ti simplify boot, but leaves more
244 complex tasks to userspace (e.g. udev).
248 config KERNEL_DEVTMPFS_MOUNT
249 bool "Automatically mount devtmpfs after root filesystem is mounted"
255 # CGROUP support symbols
258 config KERNEL_CGROUPS
259 bool "Enable kernel cgroups"
264 config KERNEL_CGROUP_DEBUG
265 bool "Example debug cgroup subsystem"
268 This option enables a simple cgroup subsystem that
269 exports useful debugging information about the cgroups
272 config KERNEL_FREEZER
274 default y if KERNEL_CGROUP_FREEZER
276 config KERNEL_CGROUP_FREEZER
277 bool "Freezer cgroup subsystem"
280 Provides a way to freeze and unfreeze all tasks in a
283 config KERNEL_CGROUP_DEVICE
284 bool "Device controller for cgroups"
287 Provides a cgroup implementing whitelists for devices which
288 a process in the cgroup can mknod or open.
290 config KERNEL_CGROUP_PIDS
291 bool "PIDs cgroup subsystem"
294 Provides enforcement of process number limits in the scope of a
297 config KERNEL_CPUSETS
298 bool "Cpuset support"
301 This option will let you create and manage CPUSETs which
302 allow dynamically partitioning a system into sets of CPUs and
303 Memory Nodes and assigning tasks to run only within those sets.
304 This is primarily useful on large SMP or NUMA systems.
306 config KERNEL_PROC_PID_CPUSET
307 bool "Include legacy /proc/<pid>/cpuset file"
309 depends on KERNEL_CPUSETS
311 config KERNEL_CGROUP_CPUACCT
312 bool "Simple CPU accounting cgroup subsystem"
315 Provides a simple Resource Controller for monitoring the
316 total CPU consumed by the tasks in a cgroup.
318 config KERNEL_RESOURCE_COUNTERS
319 bool "Resource counters"
322 This option enables controller independent resource accounting
323 infrastructure that works with cgroups.
325 config KERNEL_MM_OWNER
327 default y if KERNEL_MEMCG
330 bool "Memory Resource Controller for Control Groups"
332 depends on KERNEL_RESOURCE_COUNTERS || !LINUX_3_18
334 Provides a memory resource controller that manages both anonymous
335 memory and page cache. (See Documentation/cgroups/memory.txt)
337 Note that setting this option increases fixed memory overhead
338 associated with each page of memory in the system. By this,
339 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
340 usage tracking struct at boot. Total amount of this is printed out
343 Only enable when you're ok with these tradeoffs and really
344 sure you need the memory resource controller. Even when you enable
345 this, you can set "cgroup_disable=memory" at your boot option to
346 disable memory resource controller and you can avoid overheads
347 (but lose benefits of memory resource controller).
349 This config option also selects MM_OWNER config option, which
350 could in turn add some fork/exit overhead.
352 config KERNEL_MEMCG_SWAP
353 bool "Memory Resource Controller Swap Extension"
355 depends on KERNEL_MEMCG
357 Add swap management feature to memory resource controller. When you
358 enable this, you can limit mem+swap usage per cgroup. In other words,
359 when you disable this, memory resource controller has no cares to
360 usage of swap...a process can exhaust all of the swap. This extension
361 is useful when you want to avoid exhaustion swap but this itself
362 adds more overheads and consumes memory for remembering information.
363 Especially if you use 32bit system or small memory system, please
364 be careful about enabling this. When memory resource controller
365 is disabled by boot option, this will be automatically disabled and
366 there will be no overhead from this. Even when you set this config=y,
367 if boot option "swapaccount=0" is set, swap will not be accounted.
368 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
369 size is 4096bytes, 512k per 1Gbytes of swap.
371 config KERNEL_MEMCG_SWAP_ENABLED
372 bool "Memory Resource Controller Swap Extension enabled by default"
374 depends on KERNEL_MEMCG_SWAP
376 Memory Resource Controller Swap Extension comes with its price in
377 a bigger memory consumption. General purpose distribution kernels
378 which want to enable the feature but keep it disabled by default
379 and let the user enable it by swapaccount boot command line
380 parameter should have this option unselected.
382 Those who want to have the feature enabled by default should
383 select this option (if, for some reason, they need to disable it,
384 then swapaccount=0 does the trick).
387 config KERNEL_MEMCG_KMEM
388 bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
390 depends on KERNEL_MEMCG
392 The Kernel Memory extension for Memory Resource Controller can limit
393 the amount of memory used by kernel objects in the system. Those are
394 fundamentally different from the entities handled by the standard
395 Memory Controller, which are page-based, and can be swapped. Users of
396 the kmem extension can use it to guarantee that no group of processes
397 will ever exhaust kernel resources alone.
399 config KERNEL_CGROUP_PERF
400 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
401 select KERNEL_PERF_EVENTS
404 This option extends the per-cpu mode to restrict monitoring to
405 threads which belong to the cgroup specified and run on the
408 menuconfig KERNEL_CGROUP_SCHED
409 bool "Group CPU scheduler"
412 This feature lets CPU scheduler recognize task groups and control CPU
413 bandwidth allocation to such task groups. It uses cgroups to group
416 if KERNEL_CGROUP_SCHED
418 config KERNEL_FAIR_GROUP_SCHED
419 bool "Group scheduling for SCHED_OTHER"
422 config KERNEL_CFS_BANDWIDTH
423 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
425 depends on KERNEL_FAIR_GROUP_SCHED
427 This option allows users to define CPU bandwidth rates (limits) for
428 tasks running within the fair group scheduler. Groups with no limit
429 set are considered to be unconstrained and will run with no
431 See tip/Documentation/scheduler/sched-bwc.txt for more information.
433 config KERNEL_RT_GROUP_SCHED
434 bool "Group scheduling for SCHED_RR/FIFO"
437 This feature lets you explicitly allocate real CPU bandwidth
438 to task groups. If enabled, it will also make it impossible to
439 schedule realtime tasks for non-root users until you allocate
440 realtime bandwidth for them.
444 config KERNEL_BLK_CGROUP
445 bool "Block IO controller"
448 Generic block IO controller cgroup interface. This is the common
449 cgroup interface which should be used by various IO controlling
452 Currently, CFQ IO scheduler uses it to recognize task groups and
453 control disk bandwidth allocation (proportional time slice allocation)
454 to such task groups. It is also used by bio throttling logic in
455 block layer to implement upper limit in IO rates on a device.
457 This option only enables generic Block IO controller infrastructure.
458 One needs to also enable actual IO controlling logic/policy. For
459 enabling proportional weight division of disk bandwidth in CFQ, set
460 CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
461 CONFIG_BLK_DEV_THROTTLING=y.
463 config KERNEL_DEBUG_BLK_CGROUP
464 bool "Enable Block IO controller debugging"
466 depends on KERNEL_BLK_CGROUP
468 Enable some debugging help. Currently it exports additional stat
469 files in a cgroup which can be useful for debugging.
471 config KERNEL_NET_CLS_CGROUP
472 bool "Control Group Classifier"
475 config KERNEL_NETPRIO_CGROUP
476 bool "Network priority cgroup"
482 # Namespace support symbols
485 config KERNEL_NAMESPACES
486 bool "Enable kernel namespaces"
495 In this namespace, tasks see different info provided
496 with the uname() system call.
502 In this namespace, tasks work with IPC ids which correspond to
503 different IPC objects in different namespaces.
505 config KERNEL_USER_NS
506 bool "User namespace (EXPERIMENTAL)"
509 This allows containers, i.e. vservers, to use user namespaces
510 to provide different user info for different servers.
513 bool "PID Namespaces"
516 Support process id namespaces. This allows having multiple
517 processes with the same pid as long as they are in different
518 pid namespaces. This is a building block of containers.
521 bool "Network namespace"
524 Allow user space to create what appear to be multiple instances
525 of the network stack.
530 # LXC related symbols
533 config KERNEL_LXC_MISC
534 bool "Enable miscellaneous LXC related options"
539 config KERNEL_DEVPTS_MULTIPLE_INSTANCES
540 bool "Support multiple instances of devpts"
543 Enable support for multiple instances of devpts filesystem.
544 If you want to have isolated PTY namespaces (eg: in containers),
545 say Y here. Otherwise, say N. If enabled, each mount of devpts
546 filesystem with the '-o newinstance' option will create an
547 independent PTY namespace.
549 config KERNEL_POSIX_MQUEUE
550 bool "POSIX Message Queues"
553 POSIX variant of message queues is a part of IPC. In POSIX message
554 queues every message has a priority which decides about succession
555 of receiving it by a process. If you want to compile and run
556 programs written e.g. for Solaris with use of its POSIX message
557 queues (functions mq_*) say Y here.
559 POSIX message queues are visible as a filesystem called 'mqueue'
560 and can be mounted somewhere if you want to do filesystem
561 operations on message queues.
565 config KERNEL_SECCOMP_FILTER
569 config KERNEL_SECCOMP
570 bool "Enable seccomp support"
571 depends on !(TARGET_uml)
572 select KERNEL_SECCOMP_FILTER
575 Build kernel with support for seccomp.
586 config KERNEL_IPV6_MULTIPLE_TABLES
589 config KERNEL_IPV6_SUBTREES
592 config KERNEL_IPV6_MROUTE
595 config KERNEL_IPV6_PIMSM_V2
601 # NFS related symbols
604 bool "Compile the kernel with rootfs on NFS"
606 If you want to make your kernel boot off a NFS server as root
607 filesystem, select Y here.
611 config KERNEL_IP_PNP_DHCP
614 config KERNEL_IP_PNP_BOOTP
617 config KERNEL_IP_PNP_RARP
629 config KERNEL_ROOT_NFS