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 7config KERNEL_BUILD_USER 8 string "Custom Kernel Build User Name" 9 default "" 10 help 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. 14 15config KERNEL_BUILD_DOMAIN 16 string "Custom Kernel Build Domain Name" 17 default "" 18 help 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. 22 23config KERNEL_PRINTK 24 bool "Enable support for printk" 25 default y 26 27config KERNEL_CRASHLOG 28 bool "Crash logging" 29 depends on !(arm || powerpc || sparc || TARGET_uml) 30 default y 31 32config KERNEL_SWAP 33 bool "Support for paging of anonymous memory (swap)" 34 default y 35 36config KERNEL_DEBUG_FS 37 bool "Compile the kernel with debug filesystem enabled" 38 default y 39 help 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. 44 45config KERNEL_ARM_PMU 46 bool 47 default n 48 depends on (arm || arm64) 49 50config KERNEL_PERF_EVENTS 51 bool 52 default n 53 select KERNEL_ARM_PMU if (arm || arm64) 54 55config KERNEL_PROFILING 56 bool "Compile the kernel with profiling enabled" 57 default n 58 select KERNEL_PERF_EVENTS 59 help 60 Enable the extended profiling support mechanisms used by profilers such 61 as OProfile. 62 63config KERNEL_KALLSYMS 64 bool "Compile the kernel with symbol table information" 65 default y 66 help 67 This will give you more information in stack traces from kernel oopses. 68 69config KERNEL_FTRACE 70 bool "Compile the kernel with tracing support" 71 depends on !TARGET_uml 72 default n 73 74config KERNEL_FTRACE_SYSCALLS 75 bool "Trace system calls" 76 depends on KERNEL_FTRACE 77 default n 78 79config KERNEL_ENABLE_DEFAULT_TRACERS 80 bool "Trace process context switches and events" 81 depends on KERNEL_FTRACE 82 default n 83 84config KERNEL_FUNCTION_TRACER 85 bool "Function tracer" 86 depends on KERNEL_FTRACE 87 default n 88 89config KERNEL_FUNCTION_GRAPH_TRACER 90 bool "Function graph tracer" 91 depends on KERNEL_FUNCTION_TRACER 92 default n 93 94config KERNEL_DYNAMIC_FTRACE 95 bool "Enable/disable function tracing dynamically" 96 depends on KERNEL_FUNCTION_TRACER 97 default n 98 99config KERNEL_FUNCTION_PROFILER 100 bool "Function profiler" 101 depends on KERNEL_FUNCTION_TRACER 102 default n 103 104config KERNEL_DEBUG_KERNEL 105 bool 106 default n 107 108config KERNEL_DEBUG_INFO 109 bool "Compile the kernel with debug information" 110 default y 111 select KERNEL_DEBUG_KERNEL 112 help 113 This will compile your kernel and modules with debug information. 114 115config KERNEL_DEBUG_LL_UART_NONE 116 bool 117 default n 118 depends on arm 119 120config KERNEL_DEBUG_LL 121 bool 122 default n 123 depends on arm 124 select KERNEL_DEBUG_LL_UART_NONE 125 help 126 ARM low level debugging. 127 128config KERNEL_DYNAMIC_DEBUG 129 bool "Compile the kernel with dynamic printk" 130 select KERNEL_DEBUG_FS 131 default n 132 help 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%. 139 140config KERNEL_EARLY_PRINTK 141 bool "Compile the kernel with early printk" 142 default y if TARGET_bcm53xx 143 default n 144 depends on arm 145 select KERNEL_DEBUG_KERNEL 146 select KERNEL_DEBUG_LL if arm 147 help 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. 151 152config KERNEL_KPROBES 153 bool "Compile the kernel with kprobes support" 154 default n 155 select KERNEL_FTRACE 156 select KERNEL_PERF_EVENTS 157 help 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". 164 165config KERNEL_KPROBE_EVENT 166 bool 167 default y if KERNEL_KPROBES 168 169config KERNEL_AIO 170 bool "Compile the kernel with asynchronous IO support" 171 default n 172 173config KERNEL_DIRECT_IO 174 bool "Compile the kernel with direct IO support" 175 default n 176 177config KERNEL_FHANDLE 178 bool "Compile the kernel with support for fhandle syscalls" 179 default n 180 181config KERNEL_FANOTIFY 182 bool "Compile the kernel with modern file notification support" 183 default n 184 185config KERNEL_BLK_DEV_BSG 186 bool "Compile the kernel with SCSI generic v4 support for any block device" 187 default n 188 189config KERNEL_MAGIC_SYSRQ 190 bool "Compile the kernel with SysRq support" 191 default y 192 193config KERNEL_COREDUMP 194 bool 195 196config KERNEL_ELF_CORE 197 bool "Enable process core dump support" 198 select KERNEL_COREDUMP 199 default y 200 201config KERNEL_PROVE_LOCKING 202 bool "Enable kernel lock checking" 203 select KERNEL_DEBUG_KERNEL 204 default n 205 206config KERNEL_PRINTK_TIME 207 bool "Enable printk timestamps" 208 default y 209 210config KERNEL_SLUB_DEBUG 211 bool 212 213config KERNEL_SLUB_DEBUG_ON 214 bool 215 216config KERNEL_SLABINFO 217 select KERNEL_SLUB_DEBUG 218 select KERNEL_SLUB_DEBUG_ON 219 bool "Enable /proc slab debug info" 220 221config KERNEL_PROC_PAGE_MONITOR 222 bool "Enable /proc page monitoring" 223 224config KERNEL_RELAY 225 bool 226 227config KERNEL_KEXEC 228 bool "Enable kexec support" 229 230config USE_RFKILL 231 bool "Enable rfkill support" 232 default RFKILL_SUPPORT 233 234config USE_SPARSE 235 bool "Enable sparse check during kernel build" 236 default n 237 238config KERNEL_DEVTMPFS 239 bool "Compile the kernel with device tmpfs enabled" 240 default n 241 help 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). 245 246if KERNEL_DEVTMPFS 247 248 config KERNEL_DEVTMPFS_MOUNT 249 bool "Automatically mount devtmpfs after root filesystem is mounted" 250 default n 251 252endif 253 254# 255# CGROUP support symbols 256# 257 258config KERNEL_CGROUPS 259 bool "Enable kernel cgroups" 260 default n 261 262if KERNEL_CGROUPS 263 264 config KERNEL_CGROUP_DEBUG 265 bool "Example debug cgroup subsystem" 266 default n 267 help 268 This option enables a simple cgroup subsystem that 269 exports useful debugging information about the cgroups 270 framework. 271 272 config KERNEL_FREEZER 273 bool 274 default y if KERNEL_CGROUP_FREEZER 275 276 config KERNEL_CGROUP_FREEZER 277 bool "Freezer cgroup subsystem" 278 default y 279 help 280 Provides a way to freeze and unfreeze all tasks in a 281 cgroup. 282 283 config KERNEL_CGROUP_DEVICE 284 bool "Device controller for cgroups" 285 default y 286 help 287 Provides a cgroup implementing whitelists for devices which 288 a process in the cgroup can mknod or open. 289 290 config KERNEL_CGROUP_PIDS 291 bool "PIDs cgroup subsystem" 292 default y 293 help 294 Provides enforcement of process number limits in the scope of a 295 cgroup. 296 297 config KERNEL_CPUSETS 298 bool "Cpuset support" 299 default n 300 help 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. 305 306 config KERNEL_PROC_PID_CPUSET 307 bool "Include legacy /proc/<pid>/cpuset file" 308 default n 309 depends on KERNEL_CPUSETS 310 311 config KERNEL_CGROUP_CPUACCT 312 bool "Simple CPU accounting cgroup subsystem" 313 default n 314 help 315 Provides a simple Resource Controller for monitoring the 316 total CPU consumed by the tasks in a cgroup. 317 318 config KERNEL_RESOURCE_COUNTERS 319 bool "Resource counters" 320 default n 321 help 322 This option enables controller independent resource accounting 323 infrastructure that works with cgroups. 324 325 config KERNEL_MM_OWNER 326 bool 327 default y if KERNEL_MEMCG 328 329 config KERNEL_MEMCG 330 bool "Memory Resource Controller for Control Groups" 331 default n 332 depends on KERNEL_RESOURCE_COUNTERS || !LINUX_3_18 333 help 334 Provides a memory resource controller that manages both anonymous 335 memory and page cache. (See Documentation/cgroups/memory.txt) 336 337 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 341 at boot. 342 343 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). 348 349 This config option also selects MM_OWNER config option, which 350 could in turn add some fork/exit overhead. 351 352 config KERNEL_MEMCG_SWAP 353 bool "Memory Resource Controller Swap Extension" 354 default n 355 depends on KERNEL_MEMCG 356 help 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. 370 371 config KERNEL_MEMCG_SWAP_ENABLED 372 bool "Memory Resource Controller Swap Extension enabled by default" 373 default n 374 depends on KERNEL_MEMCG_SWAP 375 help 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. 381 382 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). 385 386 387 config KERNEL_MEMCG_KMEM 388 bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)" 389 default n 390 depends on KERNEL_MEMCG 391 help 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. 398 399 config KERNEL_CGROUP_PERF 400 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring" 401 select KERNEL_PERF_EVENTS 402 default n 403 help 404 This option extends the per-cpu mode to restrict monitoring to 405 threads which belong to the cgroup specified and run on the 406 designated cpu. 407 408 menuconfig KERNEL_CGROUP_SCHED 409 bool "Group CPU scheduler" 410 default n 411 help 412 This feature lets CPU scheduler recognize task groups and control CPU 413 bandwidth allocation to such task groups. It uses cgroups to group 414 tasks. 415 416 if KERNEL_CGROUP_SCHED 417 418 config KERNEL_FAIR_GROUP_SCHED 419 bool "Group scheduling for SCHED_OTHER" 420 default n 421 422 config KERNEL_CFS_BANDWIDTH 423 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED" 424 default n 425 depends on KERNEL_FAIR_GROUP_SCHED 426 help 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 430 restriction. 431 See tip/Documentation/scheduler/sched-bwc.txt for more information. 432 433 config KERNEL_RT_GROUP_SCHED 434 bool "Group scheduling for SCHED_RR/FIFO" 435 default n 436 help 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. 441 442 endif 443 444 config KERNEL_BLK_CGROUP 445 bool "Block IO controller" 446 default y 447 help 448 Generic block IO controller cgroup interface. This is the common 449 cgroup interface which should be used by various IO controlling 450 policies. 451 452 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. 456 457 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. 462 463 config KERNEL_DEBUG_BLK_CGROUP 464 bool "Enable Block IO controller debugging" 465 default n 466 depends on KERNEL_BLK_CGROUP 467 help 468 Enable some debugging help. Currently it exports additional stat 469 files in a cgroup which can be useful for debugging. 470 471 config KERNEL_NET_CLS_CGROUP 472 bool "Control Group Classifier" 473 default y 474 475 config KERNEL_NETPRIO_CGROUP 476 bool "Network priority cgroup" 477 default y 478 479endif 480 481# 482# Namespace support symbols 483# 484 485config KERNEL_NAMESPACES 486 bool "Enable kernel namespaces" 487 default n 488 489if KERNEL_NAMESPACES 490 491 config KERNEL_UTS_NS 492 bool "UTS namespace" 493 default y 494 help 495 In this namespace, tasks see different info provided 496 with the uname() system call. 497 498 config KERNEL_IPC_NS 499 bool "IPC namespace" 500 default y 501 help 502 In this namespace, tasks work with IPC ids which correspond to 503 different IPC objects in different namespaces. 504 505 config KERNEL_USER_NS 506 bool "User namespace (EXPERIMENTAL)" 507 default y 508 help 509 This allows containers, i.e. vservers, to use user namespaces 510 to provide different user info for different servers. 511 512 config KERNEL_PID_NS 513 bool "PID Namespaces" 514 default y 515 help 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. 519 520 config KERNEL_NET_NS 521 bool "Network namespace" 522 default y 523 help 524 Allow user space to create what appear to be multiple instances 525 of the network stack. 526 527endif 528 529# 530# LXC related symbols 531# 532 533config KERNEL_LXC_MISC 534 bool "Enable miscellaneous LXC related options" 535 default n 536 537if KERNEL_LXC_MISC 538 539 config KERNEL_DEVPTS_MULTIPLE_INSTANCES 540 bool "Support multiple instances of devpts" 541 default y 542 help 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. 548 549 config KERNEL_POSIX_MQUEUE 550 bool "POSIX Message Queues" 551 default y 552 help 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. 558 559 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. 562 563endif 564 565config KERNEL_SECCOMP_FILTER 566 bool 567 default n 568 569config KERNEL_SECCOMP 570 bool "Enable seccomp support" 571 depends on !(TARGET_uml) 572 select KERNEL_SECCOMP_FILTER 573 default n 574 help 575 Build kernel with support for seccomp. 576 577# 578# IPv6 configuration 579# 580 581config KERNEL_IPV6 582 def_bool IPV6 583 584if KERNEL_IPV6 585 586 config KERNEL_IPV6_MULTIPLE_TABLES 587 def_bool y 588 589 config KERNEL_IPV6_SUBTREES 590 def_bool y 591 592 config KERNEL_IPV6_MROUTE 593 def_bool y 594 595 config KERNEL_IPV6_PIMSM_V2 596 def_bool n 597 598endif 599 600# 601# NFS related symbols 602# 603config KERNEL_IP_PNP 604 bool "Compile the kernel with rootfs on NFS" 605 help 606 If you want to make your kernel boot off a NFS server as root 607 filesystem, select Y here. 608 609if KERNEL_IP_PNP 610 611 config KERNEL_IP_PNP_DHCP 612 def_bool y 613 614 config KERNEL_IP_PNP_BOOTP 615 def_bool n 616 617 config KERNEL_IP_PNP_RARP 618 def_bool n 619 620 config KERNEL_NFS_FS 621 def_bool y 622 623 config KERNEL_NFS_V2 624 def_bool y 625 626 config KERNEL_NFS_V3 627 def_bool y 628 629 config KERNEL_ROOT_NFS 630 def_bool y 631 632endif 633