1config ARCH 2 string 3 option env="ARCH" 4 5config KERNELVERSION 6 string 7 option env="KERNELVERSION" 8 9config DEFCONFIG_LIST 10 string 11 depends on !UML 12 option defconfig_list 13 default "/lib/modules/$UNAME_RELEASE/.config" 14 default "/etc/kernel-config" 15 default "/boot/config-$UNAME_RELEASE" 16 default "$ARCH_DEFCONFIG" 17 default "arch/$ARCH/defconfig" 18 19menu "General setup" 20 21config EXPERIMENTAL 22 bool "Prompt for development and/or incomplete code/drivers" 23 ---help--- 24 Some of the various things that Linux supports (such as network 25 drivers, file systems, network protocols, etc.) can be in a state 26 of development where the functionality, stability, or the level of 27 testing is not yet high enough for general use. This is usually 28 known as the "alpha-test" phase among developers. If a feature is 29 currently in alpha-test, then the developers usually discourage 30 uninformed widespread use of this feature by the general public to 31 avoid "Why doesn't this work?" type mail messages. However, active 32 testing and use of these systems is welcomed. Just be aware that it 33 may not meet the normal level of reliability or it may fail to work 34 in some special cases. Detailed bug reports from people familiar 35 with the kernel internals are usually welcomed by the developers 36 (before submitting bug reports, please read the documents 37 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>, 38 <file:Documentation/BUG-HUNTING>, and 39 <file:Documentation/oops-tracing.txt> in the kernel source). 40 41 This option will also make obsoleted drivers available. These are 42 drivers that have been replaced by something else, and/or are 43 scheduled to be removed in a future kernel release. 44 45 Unless you intend to help test and develop a feature or driver that 46 falls into this category, or you have a situation that requires 47 using these features, you should probably say N here, which will 48 cause the configurator to present you with fewer choices. If 49 you say Y here, you will be offered the choice of using features or 50 drivers that are currently considered to be in the alpha-test phase. 51 52config BROKEN 53 bool 54 55config BROKEN_ON_SMP 56 bool 57 depends on BROKEN || !SMP 58 default y 59 60config LOCK_KERNEL 61 bool 62 depends on SMP || PREEMPT 63 default y 64 65config INIT_ENV_ARG_LIMIT 66 int 67 default 32 if !UML 68 default 128 if UML 69 help 70 Maximum of each of the number of arguments and environment 71 variables passed to init from the kernel command line. 72 73 74config LOCALVERSION 75 string "Local version - append to kernel release" 76 help 77 Append an extra string to the end of your kernel version. 78 This will show up when you type uname, for example. 79 The string you set here will be appended after the contents of 80 any files with a filename matching localversion* in your 81 object and source tree, in that order. Your total string can 82 be a maximum of 64 characters. 83 84config LOCALVERSION_AUTO 85 bool "Automatically append version information to the version string" 86 default y 87 help 88 This will try to automatically determine if the current tree is a 89 release tree by looking for git tags that belong to the current 90 top of tree revision. 91 92 A string of the format -gxxxxxxxx will be added to the localversion 93 if a git-based tree is found. The string generated by this will be 94 appended after any matching localversion* files, and after the value 95 set in CONFIG_LOCALVERSION. 96 97 (The actual string used here is the first eight characters produced 98 by running the command: 99 100 $ git rev-parse --verify HEAD 101 102 which is done within the script "scripts/setlocalversion".) 103 104config SWAP 105 bool "Support for paging of anonymous memory (swap)" 106 depends on MMU && BLOCK 107 default y 108 help 109 This option allows you to choose whether you want to have support 110 for so called swap devices or swap files in your kernel that are 111 used to provide more virtual memory than the actual RAM present 112 in your computer. If unsure say Y. 113 114config SYSVIPC 115 bool "System V IPC" 116 ---help--- 117 Inter Process Communication is a suite of library functions and 118 system calls which let processes (running programs) synchronize and 119 exchange information. It is generally considered to be a good thing, 120 and some programs won't run unless you say Y here. In particular, if 121 you want to run the DOS emulator dosemu under Linux (read the 122 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>), 123 you'll need to say Y here. 124 125 You can find documentation about IPC with "info ipc" and also in 126 section 6.4 of the Linux Programmer's Guide, available from 127 <http://www.tldp.org/guides.html>. 128 129config SYSVIPC_SYSCTL 130 bool 131 depends on SYSVIPC 132 depends on SYSCTL 133 default y 134 135config POSIX_MQUEUE 136 bool "POSIX Message Queues" 137 depends on NET && EXPERIMENTAL 138 ---help--- 139 POSIX variant of message queues is a part of IPC. In POSIX message 140 queues every message has a priority which decides about succession 141 of receiving it by a process. If you want to compile and run 142 programs written e.g. for Solaris with use of its POSIX message 143 queues (functions mq_*) say Y here. 144 145 POSIX message queues are visible as a filesystem called 'mqueue' 146 and can be mounted somewhere if you want to do filesystem 147 operations on message queues. 148 149 If unsure, say Y. 150 151config BSD_PROCESS_ACCT 152 bool "BSD Process Accounting" 153 help 154 If you say Y here, a user level program will be able to instruct the 155 kernel (via a special system call) to write process accounting 156 information to a file: whenever a process exits, information about 157 that process will be appended to the file by the kernel. The 158 information includes things such as creation time, owning user, 159 command name, memory usage, controlling terminal etc. (the complete 160 list is in the struct acct in <file:include/linux/acct.h>). It is 161 up to the user level program to do useful things with this 162 information. This is generally a good idea, so say Y. 163 164config BSD_PROCESS_ACCT_V3 165 bool "BSD Process Accounting version 3 file format" 166 depends on BSD_PROCESS_ACCT 167 default n 168 help 169 If you say Y here, the process accounting information is written 170 in a new file format that also logs the process IDs of each 171 process and it's parent. Note that this file format is incompatible 172 with previous v0/v1/v2 file formats, so you will need updated tools 173 for processing it. A preliminary version of these tools is available 174 at <http://www.gnu.org/software/acct/>. 175 176config TASKSTATS 177 bool "Export task/process statistics through netlink (EXPERIMENTAL)" 178 depends on NET 179 default n 180 help 181 Export selected statistics for tasks/processes through the 182 generic netlink interface. Unlike BSD process accounting, the 183 statistics are available during the lifetime of tasks/processes as 184 responses to commands. Like BSD accounting, they are sent to user 185 space on task exit. 186 187 Say N if unsure. 188 189config TASK_DELAY_ACCT 190 bool "Enable per-task delay accounting (EXPERIMENTAL)" 191 depends on TASKSTATS 192 help 193 Collect information on time spent by a task waiting for system 194 resources like cpu, synchronous block I/O completion and swapping 195 in pages. Such statistics can help in setting a task's priorities 196 relative to other tasks for cpu, io, rss limits etc. 197 198 Say N if unsure. 199 200config TASK_XACCT 201 bool "Enable extended accounting over taskstats (EXPERIMENTAL)" 202 depends on TASKSTATS 203 help 204 Collect extended task accounting data and send the data 205 to userland for processing over the taskstats interface. 206 207 Say N if unsure. 208 209config TASK_IO_ACCOUNTING 210 bool "Enable per-task storage I/O accounting (EXPERIMENTAL)" 211 depends on TASK_XACCT 212 help 213 Collect information on the number of bytes of storage I/O which this 214 task has caused. 215 216 Say N if unsure. 217 218config AUDIT 219 bool "Auditing support" 220 depends on NET 221 help 222 Enable auditing infrastructure that can be used with another 223 kernel subsystem, such as SELinux (which requires this for 224 logging of avc messages output). Does not do system-call 225 auditing without CONFIG_AUDITSYSCALL. 226 227config AUDITSYSCALL 228 bool "Enable system-call auditing support" 229 depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64|| SUPERH) 230 default y if SECURITY_SELINUX 231 help 232 Enable low-overhead system-call auditing infrastructure that 233 can be used independently or with another kernel subsystem, 234 such as SELinux. To use audit's filesystem watch feature, please 235 ensure that INOTIFY is configured. 236 237config AUDIT_TREE 238 def_bool y 239 depends on AUDITSYSCALL && INOTIFY 240 241config IKCONFIG 242 tristate "Kernel .config support" 243 ---help--- 244 This option enables the complete Linux kernel ".config" file 245 contents to be saved in the kernel. It provides documentation 246 of which kernel options are used in a running kernel or in an 247 on-disk kernel. This information can be extracted from the kernel 248 image file with the script scripts/extract-ikconfig and used as 249 input to rebuild the current kernel or to build another kernel. 250 It can also be extracted from a running kernel by reading 251 /proc/config.gz if enabled (below). 252 253config IKCONFIG_PROC 254 bool "Enable access to .config through /proc/config.gz" 255 depends on IKCONFIG && PROC_FS 256 ---help--- 257 This option enables access to the kernel configuration file 258 through /proc/config.gz. 259 260config LOG_BUF_SHIFT 261 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)" 262 range 12 21 263 default 17 264 help 265 Select kernel log buffer size as a power of 2. 266 Examples: 267 17 => 128 KB 268 16 => 64 KB 269 15 => 32 KB 270 14 => 16 KB 271 13 => 8 KB 272 12 => 4 KB 273 274config CGROUPS 275 bool "Control Group support" 276 help 277 This option will let you use process cgroup subsystems 278 such as Cpusets 279 280 Say N if unsure. 281 282config CGROUP_DEBUG 283 bool "Example debug cgroup subsystem" 284 depends on CGROUPS 285 default n 286 help 287 This option enables a simple cgroup subsystem that 288 exports useful debugging information about the cgroups 289 framework 290 291 Say N if unsure 292 293config CGROUP_NS 294 bool "Namespace cgroup subsystem" 295 depends on CGROUPS 296 help 297 Provides a simple namespace cgroup subsystem to 298 provide hierarchical naming of sets of namespaces, 299 for instance virtual servers and checkpoint/restart 300 jobs. 301 302config CGROUP_FREEZER 303 bool "control group freezer subsystem" 304 depends on CGROUPS 305 help 306 Provides a way to freeze and unfreeze all tasks in a 307 cgroup. 308 309config CGROUP_DEVICE 310 bool "Device controller for cgroups" 311 depends on CGROUPS && EXPERIMENTAL 312 help 313 Provides a cgroup implementing whitelists for devices which 314 a process in the cgroup can mknod or open. 315 316config CPUSETS 317 bool "Cpuset support" 318 depends on SMP && CGROUPS 319 help 320 This option will let you create and manage CPUSETs which 321 allow dynamically partitioning a system into sets of CPUs and 322 Memory Nodes and assigning tasks to run only within those sets. 323 This is primarily useful on large SMP or NUMA systems. 324 325 Say N if unsure. 326 327# 328# Architectures with an unreliable sched_clock() should select this: 329# 330config HAVE_UNSTABLE_SCHED_CLOCK 331 bool 332 333config GROUP_SCHED 334 bool "Group CPU scheduler" 335 depends on EXPERIMENTAL 336 default n 337 help 338 This feature lets CPU scheduler recognize task groups and control CPU 339 bandwidth allocation to such task groups. 340 341config FAIR_GROUP_SCHED 342 bool "Group scheduling for SCHED_OTHER" 343 depends on GROUP_SCHED 344 default GROUP_SCHED 345 346config RT_GROUP_SCHED 347 bool "Group scheduling for SCHED_RR/FIFO" 348 depends on EXPERIMENTAL 349 depends on GROUP_SCHED 350 default n 351 help 352 This feature lets you explicitly allocate real CPU bandwidth 353 to users or control groups (depending on the "Basis for grouping tasks" 354 setting below. If enabled, it will also make it impossible to 355 schedule realtime tasks for non-root users until you allocate 356 realtime bandwidth for them. 357 See Documentation/sched-rt-group.txt for more information. 358 359choice 360 depends on GROUP_SCHED 361 prompt "Basis for grouping tasks" 362 default USER_SCHED 363 364config USER_SCHED 365 bool "user id" 366 help 367 This option will choose userid as the basis for grouping 368 tasks, thus providing equal CPU bandwidth to each user. 369 370config CGROUP_SCHED 371 bool "Control groups" 372 depends on CGROUPS 373 help 374 This option allows you to create arbitrary task groups 375 using the "cgroup" pseudo filesystem and control 376 the cpu bandwidth allocated to each such task group. 377 Refer to Documentation/cgroups.txt for more information 378 on "cgroup" pseudo filesystem. 379 380endchoice 381 382config CGROUP_CPUACCT 383 bool "Simple CPU accounting cgroup subsystem" 384 depends on CGROUPS 385 help 386 Provides a simple Resource Controller for monitoring the 387 total CPU consumed by the tasks in a cgroup 388 389config RESOURCE_COUNTERS 390 bool "Resource counters" 391 help 392 This option enables controller independent resource accounting 393 infrastructure that works with cgroups 394 depends on CGROUPS 395 396config MM_OWNER 397 bool 398 399config CGROUP_MEM_RES_CTLR 400 bool "Memory Resource Controller for Control Groups" 401 depends on CGROUPS && RESOURCE_COUNTERS 402 select MM_OWNER 403 help 404 Provides a memory resource controller that manages both page cache and 405 RSS memory. 406 407 Note that setting this option increases fixed memory overhead 408 associated with each page of memory in the system by 4/8 bytes 409 and also increases cache misses because struct page on many 64bit 410 systems will not fit into a single cache line anymore. 411 412 Only enable when you're ok with these trade offs and really 413 sure you need the memory resource controller. 414 415 This config option also selects MM_OWNER config option, which 416 could in turn add some fork/exit overhead. 417 418config SYSFS_DEPRECATED 419 bool 420 421config SYSFS_DEPRECATED_V2 422 bool "Create deprecated sysfs files" 423 depends on SYSFS 424 default y 425 select SYSFS_DEPRECATED 426 help 427 This option creates deprecated symlinks such as the 428 "device"-link, the <subsystem>:<name>-link, and the 429 "bus"-link. It may also add deprecated key in the 430 uevent environment. 431 None of these features or values should be used today, as 432 they export driver core implementation details to userspace 433 or export properties which can't be kept stable across kernel 434 releases. 435 436 If enabled, this option will also move any device structures 437 that belong to a class, back into the /sys/class hierarchy, in 438 order to support older versions of udev and some userspace 439 programs. 440 441 If you are using a distro with the most recent userspace 442 packages, it should be safe to say N here. 443 444config PROC_PID_CPUSET 445 bool "Include legacy /proc/<pid>/cpuset file" 446 depends on CPUSETS 447 default y 448 449config RELAY 450 bool "Kernel->user space relay support (formerly relayfs)" 451 help 452 This option enables support for relay interface support in 453 certain file systems (such as debugfs). 454 It is designed to provide an efficient mechanism for tools and 455 facilities to relay large amounts of data from kernel space to 456 user space. 457 458 If unsure, say N. 459 460config NAMESPACES 461 bool "Namespaces support" if EMBEDDED 462 default !EMBEDDED 463 help 464 Provides the way to make tasks work with different objects using 465 the same id. For example same IPC id may refer to different objects 466 or same user id or pid may refer to different tasks when used in 467 different namespaces. 468 469config UTS_NS 470 bool "UTS namespace" 471 depends on NAMESPACES 472 help 473 In this namespace tasks see different info provided with the 474 uname() system call 475 476config IPC_NS 477 bool "IPC namespace" 478 depends on NAMESPACES && SYSVIPC 479 help 480 In this namespace tasks work with IPC ids which correspond to 481 different IPC objects in different namespaces 482 483config USER_NS 484 bool "User namespace (EXPERIMENTAL)" 485 depends on NAMESPACES && EXPERIMENTAL 486 help 487 This allows containers, i.e. vservers, to use user namespaces 488 to provide different user info for different servers. 489 If unsure, say N. 490 491config PID_NS 492 bool "PID Namespaces (EXPERIMENTAL)" 493 default n 494 depends on NAMESPACES && EXPERIMENTAL 495 help 496 Support process id namespaces. This allows having multiple 497 process with the same pid as long as they are in different 498 pid namespaces. This is a building block of containers. 499 500 Unless you want to work with an experimental feature 501 say N here. 502 503config BLK_DEV_INITRD 504 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support" 505 depends on BROKEN || !FRV 506 help 507 The initial RAM filesystem is a ramfs which is loaded by the 508 boot loader (loadlin or lilo) and that is mounted as root 509 before the normal boot procedure. It is typically used to 510 load modules needed to mount the "real" root file system, 511 etc. See <file:Documentation/initrd.txt> for details. 512 513 If RAM disk support (BLK_DEV_RAM) is also included, this 514 also enables initial RAM disk (initrd) support and adds 515 15 Kbytes (more on some other architectures) to the kernel size. 516 517 If unsure say Y. 518 519if BLK_DEV_INITRD 520 521source "usr/Kconfig" 522 523endif 524 525config CC_OPTIMIZE_FOR_SIZE 526 bool "Optimize for size" 527 default y 528 help 529 Enabling this option will pass "-Os" instead of "-O2" to gcc 530 resulting in a smaller kernel. 531 532 If unsure, say Y. 533 534config SYSCTL 535 bool 536 537menuconfig EMBEDDED 538 bool "Configure standard kernel features (for small systems)" 539 help 540 This option allows certain base kernel options and settings 541 to be disabled or tweaked. This is for specialized 542 environments which can tolerate a "non-standard" kernel. 543 Only use this if you really know what you are doing. 544 545config UID16 546 bool "Enable 16-bit UID system calls" if EMBEDDED 547 depends on ARM || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && COMPAT) || UML || (X86_64 && IA32_EMULATION) 548 default y 549 help 550 This enables the legacy 16-bit UID syscall wrappers. 551 552config SYSCTL_SYSCALL 553 bool "Sysctl syscall support" if EMBEDDED 554 default y 555 select SYSCTL 556 ---help--- 557 sys_sysctl uses binary paths that have been found challenging 558 to properly maintain and use. The interface in /proc/sys 559 using paths with ascii names is now the primary path to this 560 information. 561 562 Almost nothing using the binary sysctl interface so if you are 563 trying to save some space it is probably safe to disable this, 564 making your kernel marginally smaller. 565 566 If unsure say Y here. 567 568config KALLSYMS 569 bool "Load all symbols for debugging/ksymoops" if EMBEDDED 570 default y 571 help 572 Say Y here to let the kernel print out symbolic crash information and 573 symbolic stack backtraces. This increases the size of the kernel 574 somewhat, as all symbols have to be loaded into the kernel image. 575 576config KALLSYMS_ALL 577 bool "Include all symbols in kallsyms" 578 depends on DEBUG_KERNEL && KALLSYMS 579 help 580 Normally kallsyms only contains the symbols of functions, for nicer 581 OOPS messages. Some debuggers can use kallsyms for other 582 symbols too: say Y here to include all symbols, if you need them 583 and you don't care about adding 300k to the size of your kernel. 584 585 Say N. 586 587config KALLSYMS_EXTRA_PASS 588 bool "Do an extra kallsyms pass" 589 depends on KALLSYMS 590 help 591 If kallsyms is not working correctly, the build will fail with 592 inconsistent kallsyms data. If that occurs, log a bug report and 593 turn on KALLSYMS_EXTRA_PASS which should result in a stable build. 594 Always say N here unless you find a bug in kallsyms, which must be 595 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while 596 you wait for kallsyms to be fixed. 597 598 599config HOTPLUG 600 bool "Support for hot-pluggable devices" if EMBEDDED 601 default y 602 help 603 This option is provided for the case where no hotplug or uevent 604 capabilities is wanted by the kernel. You should only consider 605 disabling this option for embedded systems that do not use modules, a 606 dynamic /dev tree, or dynamic device discovery. Just say Y. 607 608config PRINTK 609 default y 610 bool "Enable support for printk" if EMBEDDED 611 help 612 This option enables normal printk support. Removing it 613 eliminates most of the message strings from the kernel image 614 and makes the kernel more or less silent. As this makes it 615 very difficult to diagnose system problems, saying N here is 616 strongly discouraged. 617 618config BUG 619 bool "BUG() support" if EMBEDDED 620 default y 621 help 622 Disabling this option eliminates support for BUG and WARN, reducing 623 the size of your kernel image and potentially quietly ignoring 624 numerous fatal conditions. You should only consider disabling this 625 option for embedded systems with no facilities for reporting errors. 626 Just say Y. 627 628config ELF_CORE 629 default y 630 bool "Enable ELF core dumps" if EMBEDDED 631 help 632 Enable support for generating core dumps. Disabling saves about 4k. 633 634config PCSPKR_PLATFORM 635 bool "Enable PC-Speaker support" if EMBEDDED 636 depends on ALPHA || X86 || MIPS || PPC_PREP || PPC_CHRP || PPC_PSERIES 637 default y 638 help 639 This option allows to disable the internal PC-Speaker 640 support, saving some memory. 641 642config COMPAT_BRK 643 bool "Disable heap randomization" 644 default y 645 help 646 Randomizing heap placement makes heap exploits harder, but it 647 also breaks ancient binaries (including anything libc5 based). 648 This option changes the bootup default to heap randomization 649 disabled, and can be overriden runtime by setting 650 /proc/sys/kernel/randomize_va_space to 2. 651 652 On non-ancient distros (post-2000 ones) N is usually a safe choice. 653 654config BASE_FULL 655 default y 656 bool "Enable full-sized data structures for core" if EMBEDDED 657 help 658 Disabling this option reduces the size of miscellaneous core 659 kernel data structures. This saves memory on small machines, 660 but may reduce performance. 661 662config FUTEX 663 bool "Enable futex support" if EMBEDDED 664 default y 665 select RT_MUTEXES 666 help 667 Disabling this option will cause the kernel to be built without 668 support for "fast userspace mutexes". The resulting kernel may not 669 run glibc-based applications correctly. 670 671config ANON_INODES 672 bool 673 674config EPOLL 675 bool "Enable eventpoll support" if EMBEDDED 676 default y 677 select ANON_INODES 678 help 679 Disabling this option will cause the kernel to be built without 680 support for epoll family of system calls. 681 682config SIGNALFD 683 bool "Enable signalfd() system call" if EMBEDDED 684 select ANON_INODES 685 default y 686 help 687 Enable the signalfd() system call that allows to receive signals 688 on a file descriptor. 689 690 If unsure, say Y. 691 692config TIMERFD 693 bool "Enable timerfd() system call" if EMBEDDED 694 select ANON_INODES 695 default y 696 help 697 Enable the timerfd() system call that allows to receive timer 698 events on a file descriptor. 699 700 If unsure, say Y. 701 702config EVENTFD 703 bool "Enable eventfd() system call" if EMBEDDED 704 select ANON_INODES 705 default y 706 help 707 Enable the eventfd() system call that allows to receive both 708 kernel notification (ie. KAIO) or userspace notifications. 709 710 If unsure, say Y. 711 712config SHMEM 713 bool "Use full shmem filesystem" if EMBEDDED 714 default y 715 depends on MMU 716 help 717 The shmem is an internal filesystem used to manage shared memory. 718 It is backed by swap and manages resource limits. It is also exported 719 to userspace as tmpfs if TMPFS is enabled. Disabling this 720 option replaces shmem and tmpfs with the much simpler ramfs code, 721 which may be appropriate on small systems without swap. 722 723config AIO 724 bool "Enable AIO support" if EMBEDDED 725 default y 726 help 727 This option enables POSIX asynchronous I/O which may by used 728 by some high performance threaded applications. Disabling 729 this option saves about 7k. 730 731config VM_EVENT_COUNTERS 732 default y 733 bool "Enable VM event counters for /proc/vmstat" if EMBEDDED 734 help 735 VM event counters are needed for event counts to be shown. 736 This option allows the disabling of the VM event counters 737 on EMBEDDED systems. /proc/vmstat will only show page counts 738 if VM event counters are disabled. 739 740config PCI_QUIRKS 741 default y 742 bool "Enable PCI quirk workarounds" if EMBEDDED && PCI 743 help 744 This enables workarounds for various PCI chipset 745 bugs/quirks. Disable this only if your target machine is 746 unaffected by PCI quirks. 747 748config SLUB_DEBUG 749 default y 750 bool "Enable SLUB debugging support" if EMBEDDED 751 depends on SLUB && SYSFS 752 help 753 SLUB has extensive debug support features. Disabling these can 754 result in significant savings in code size. This also disables 755 SLUB sysfs support. /sys/slab will not exist and there will be 756 no support for cache validation etc. 757 758choice 759 prompt "Choose SLAB allocator" 760 default SLUB 761 help 762 This option allows to select a slab allocator. 763 764config SLAB 765 bool "SLAB" 766 help 767 The regular slab allocator that is established and known to work 768 well in all environments. It organizes cache hot objects in 769 per cpu and per node queues. SLAB is the default choice for 770 a slab allocator. 771 772config SLUB 773 bool "SLUB (Unqueued Allocator)" 774 help 775 SLUB is a slab allocator that minimizes cache line usage 776 instead of managing queues of cached objects (SLAB approach). 777 Per cpu caching is realized using slabs of objects instead 778 of queues of objects. SLUB can use memory efficiently 779 and has enhanced diagnostics. 780 781config SLOB 782 depends on EMBEDDED 783 bool "SLOB (Simple Allocator)" 784 help 785 SLOB replaces the stock allocator with a drastically simpler 786 allocator. SLOB is generally more space efficient but 787 does not perform as well on large systems. 788 789endchoice 790 791config PROFILING 792 bool "Profiling support (EXPERIMENTAL)" 793 help 794 Say Y here to enable the extended profiling support mechanisms used 795 by profilers such as OProfile. 796 797# 798# Place an empty function call at each tracepoint site. Can be 799# dynamically changed for a probe function. 800# 801config TRACEPOINTS 802 bool 803 804config MARKERS 805 bool "Activate markers" 806 help 807 Place an empty function call at each marker site. Can be 808 dynamically changed for a probe function. 809 810source "arch/Kconfig" 811 812endmenu # General setup 813 814config HAVE_GENERIC_DMA_COHERENT 815 bool 816 default n 817 818config SLABINFO 819 bool 820 depends on PROC_FS 821 depends on SLAB || SLUB_DEBUG 822 default y 823 824config RT_MUTEXES 825 boolean 826 select PLIST 827 828config TINY_SHMEM 829 default !SHMEM 830 bool 831 832config BASE_SMALL 833 int 834 default 0 if BASE_FULL 835 default 1 if !BASE_FULL 836 837menuconfig MODULES 838 bool "Enable loadable module support" 839 help 840 Kernel modules are small pieces of compiled code which can 841 be inserted in the running kernel, rather than being 842 permanently built into the kernel. You use the "modprobe" 843 tool to add (and sometimes remove) them. If you say Y here, 844 many parts of the kernel can be built as modules (by 845 answering M instead of Y where indicated): this is most 846 useful for infrequently used options which are not required 847 for booting. For more information, see the man pages for 848 modprobe, lsmod, modinfo, insmod and rmmod. 849 850 If you say Y here, you will need to run "make 851 modules_install" to put the modules under /lib/modules/ 852 where modprobe can find them (you may need to be root to do 853 this). 854 855 If unsure, say Y. 856 857if MODULES 858 859config MODULE_FORCE_LOAD 860 bool "Forced module loading" 861 default n 862 help 863 Allow loading of modules without version information (ie. modprobe 864 --force). Forced module loading sets the 'F' (forced) taint flag and 865 is usually a really bad idea. 866 867config MODULE_UNLOAD 868 bool "Module unloading" 869 help 870 Without this option you will not be able to unload any 871 modules (note that some modules may not be unloadable 872 anyway), which makes your kernel smaller, faster 873 and simpler. If unsure, say Y. 874 875config MODULE_FORCE_UNLOAD 876 bool "Forced module unloading" 877 depends on MODULE_UNLOAD && EXPERIMENTAL 878 help 879 This option allows you to force a module to unload, even if the 880 kernel believes it is unsafe: the kernel will remove the module 881 without waiting for anyone to stop using it (using the -f option to 882 rmmod). This is mainly for kernel developers and desperate users. 883 If unsure, say N. 884 885config MODVERSIONS 886 bool "Module versioning support" 887 help 888 Usually, you have to use modules compiled with your kernel. 889 Saying Y here makes it sometimes possible to use modules 890 compiled for different kernels, by adding enough information 891 to the modules to (hopefully) spot any changes which would 892 make them incompatible with the kernel you are running. If 893 unsure, say N. 894 895config MODULE_SRCVERSION_ALL 896 bool "Source checksum for all modules" 897 help 898 Modules which contain a MODULE_VERSION get an extra "srcversion" 899 field inserted into their modinfo section, which contains a 900 sum of the source files which made it. This helps maintainers 901 see exactly which source was used to build a module (since 902 others sometimes change the module source without updating 903 the version). With this option, such a "srcversion" field 904 will be created for all modules. If unsure, say N. 905 906config KMOD 907 def_bool y 908 help 909 This is being removed soon. These days, CONFIG_MODULES 910 implies CONFIG_KMOD, so use that instead. 911 912endif # MODULES 913 914config STOP_MACHINE 915 bool 916 default y 917 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU 918 help 919 Need stop_machine() primitive. 920 921source "block/Kconfig" 922 923config PREEMPT_NOTIFIERS 924 bool 925 926config CLASSIC_RCU 927 def_bool !PREEMPT_RCU 928 help 929 This option selects the classic RCU implementation that is 930 designed for best read-side performance on non-realtime 931 systems. Classic RCU is the default. Note that the 932 PREEMPT_RCU symbol is used to select/deselect this option. 933