| 1 | config ARCH |
| 2 | string |
| 3 | option env="ARCH" |
| 4 | |
| 5 | config KERNELVERSION |
| 6 | string |
| 7 | option env="KERNELVERSION" |
| 8 | |
| 9 | config 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 | |
| 19 | config CONSTRUCTORS |
| 20 | bool |
| 21 | depends on !UML |
| 22 | default y |
| 23 | |
| 24 | menu "General setup" |
| 25 | |
| 26 | config EXPERIMENTAL |
| 27 | bool "Prompt for development and/or incomplete code/drivers" |
| 28 | ---help--- |
| 29 | Some of the various things that Linux supports (such as network |
| 30 | drivers, file systems, network protocols, etc.) can be in a state |
| 31 | of development where the functionality, stability, or the level of |
| 32 | testing is not yet high enough for general use. This is usually |
| 33 | known as the "alpha-test" phase among developers. If a feature is |
| 34 | currently in alpha-test, then the developers usually discourage |
| 35 | uninformed widespread use of this feature by the general public to |
| 36 | avoid "Why doesn't this work?" type mail messages. However, active |
| 37 | testing and use of these systems is welcomed. Just be aware that it |
| 38 | may not meet the normal level of reliability or it may fail to work |
| 39 | in some special cases. Detailed bug reports from people familiar |
| 40 | with the kernel internals are usually welcomed by the developers |
| 41 | (before submitting bug reports, please read the documents |
| 42 | <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>, |
| 43 | <file:Documentation/BUG-HUNTING>, and |
| 44 | <file:Documentation/oops-tracing.txt> in the kernel source). |
| 45 | |
| 46 | This option will also make obsoleted drivers available. These are |
| 47 | drivers that have been replaced by something else, and/or are |
| 48 | scheduled to be removed in a future kernel release. |
| 49 | |
| 50 | Unless you intend to help test and develop a feature or driver that |
| 51 | falls into this category, or you have a situation that requires |
| 52 | using these features, you should probably say N here, which will |
| 53 | cause the configurator to present you with fewer choices. If |
| 54 | you say Y here, you will be offered the choice of using features or |
| 55 | drivers that are currently considered to be in the alpha-test phase. |
| 56 | |
| 57 | config BROKEN |
| 58 | bool |
| 59 | |
| 60 | config BROKEN_ON_SMP |
| 61 | bool |
| 62 | depends on BROKEN || !SMP |
| 63 | default y |
| 64 | |
| 65 | config LOCK_KERNEL |
| 66 | bool |
| 67 | depends on SMP || PREEMPT |
| 68 | default y |
| 69 | |
| 70 | config INIT_ENV_ARG_LIMIT |
| 71 | int |
| 72 | default 32 if !UML |
| 73 | default 128 if UML |
| 74 | help |
| 75 | Maximum of each of the number of arguments and environment |
| 76 | variables passed to init from the kernel command line. |
| 77 | |
| 78 | |
| 79 | config LOCALVERSION |
| 80 | string "Local version - append to kernel release" |
| 81 | help |
| 82 | Append an extra string to the end of your kernel version. |
| 83 | This will show up when you type uname, for example. |
| 84 | The string you set here will be appended after the contents of |
| 85 | any files with a filename matching localversion* in your |
| 86 | object and source tree, in that order. Your total string can |
| 87 | be a maximum of 64 characters. |
| 88 | |
| 89 | config LOCALVERSION_AUTO |
| 90 | bool "Automatically append version information to the version string" |
| 91 | default y |
| 92 | help |
| 93 | This will try to automatically determine if the current tree is a |
| 94 | release tree by looking for git tags that belong to the current |
| 95 | top of tree revision. |
| 96 | |
| 97 | A string of the format -gxxxxxxxx will be added to the localversion |
| 98 | if a git-based tree is found. The string generated by this will be |
| 99 | appended after any matching localversion* files, and after the value |
| 100 | set in CONFIG_LOCALVERSION. |
| 101 | |
| 102 | (The actual string used here is the first eight characters produced |
| 103 | by running the command: |
| 104 | |
| 105 | $ git rev-parse --verify HEAD |
| 106 | |
| 107 | which is done within the script "scripts/setlocalversion".) |
| 108 | |
| 109 | config HAVE_KERNEL_GZIP |
| 110 | bool |
| 111 | |
| 112 | config HAVE_KERNEL_BZIP2 |
| 113 | bool |
| 114 | |
| 115 | config HAVE_KERNEL_LZMA |
| 116 | bool |
| 117 | |
| 118 | choice |
| 119 | prompt "Kernel compression mode" |
| 120 | default KERNEL_GZIP |
| 121 | depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA |
| 122 | help |
| 123 | The linux kernel is a kind of self-extracting executable. |
| 124 | Several compression algorithms are available, which differ |
| 125 | in efficiency, compression and decompression speed. |
| 126 | Compression speed is only relevant when building a kernel. |
| 127 | Decompression speed is relevant at each boot. |
| 128 | |
| 129 | If you have any problems with bzip2 or lzma compressed |
| 130 | kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older |
| 131 | version of this functionality (bzip2 only), for 2.4, was |
| 132 | supplied by Christian Ludwig) |
| 133 | |
| 134 | High compression options are mostly useful for users, who |
| 135 | are low on disk space (embedded systems), but for whom ram |
| 136 | size matters less. |
| 137 | |
| 138 | If in doubt, select 'gzip' |
| 139 | |
| 140 | config KERNEL_GZIP |
| 141 | bool "Gzip" |
| 142 | depends on HAVE_KERNEL_GZIP |
| 143 | help |
| 144 | The old and tried gzip compression. Its compression ratio is |
| 145 | the poorest among the 3 choices; however its speed (both |
| 146 | compression and decompression) is the fastest. |
| 147 | |
| 148 | config KERNEL_BZIP2 |
| 149 | bool "Bzip2" |
| 150 | depends on HAVE_KERNEL_BZIP2 |
| 151 | help |
| 152 | Its compression ratio and speed is intermediate. |
| 153 | Decompression speed is slowest among the three. The kernel |
| 154 | size is about 10% smaller with bzip2, in comparison to gzip. |
| 155 | Bzip2 uses a large amount of memory. For modern kernels you |
| 156 | will need at least 8MB RAM or more for booting. |
| 157 | |
| 158 | config KERNEL_LZMA |
| 159 | bool "LZMA" |
| 160 | depends on HAVE_KERNEL_LZMA |
| 161 | help |
| 162 | The most recent compression algorithm. |
| 163 | Its ratio is best, decompression speed is between the other |
| 164 | two. Compression is slowest. The kernel size is about 33% |
| 165 | smaller with LZMA in comparison to gzip. |
| 166 | |
| 167 | endchoice |
| 168 | |
| 169 | config SWAP |
| 170 | bool "Support for paging of anonymous memory (swap)" |
| 171 | depends on MMU && BLOCK |
| 172 | default y |
| 173 | help |
| 174 | This option allows you to choose whether you want to have support |
| 175 | for so called swap devices or swap files in your kernel that are |
| 176 | used to provide more virtual memory than the actual RAM present |
| 177 | in your computer. If unsure say Y. |
| 178 | |
| 179 | config SYSVIPC |
| 180 | bool "System V IPC" |
| 181 | ---help--- |
| 182 | Inter Process Communication is a suite of library functions and |
| 183 | system calls which let processes (running programs) synchronize and |
| 184 | exchange information. It is generally considered to be a good thing, |
| 185 | and some programs won't run unless you say Y here. In particular, if |
| 186 | you want to run the DOS emulator dosemu under Linux (read the |
| 187 | DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>), |
| 188 | you'll need to say Y here. |
| 189 | |
| 190 | You can find documentation about IPC with "info ipc" and also in |
| 191 | section 6.4 of the Linux Programmer's Guide, available from |
| 192 | <http://www.tldp.org/guides.html>. |
| 193 | |
| 194 | config SYSVIPC_SYSCTL |
| 195 | bool |
| 196 | depends on SYSVIPC |
| 197 | depends on SYSCTL |
| 198 | default y |
| 199 | |
| 200 | config POSIX_MQUEUE |
| 201 | bool "POSIX Message Queues" |
| 202 | depends on NET && EXPERIMENTAL |
| 203 | ---help--- |
| 204 | POSIX variant of message queues is a part of IPC. In POSIX message |
| 205 | queues every message has a priority which decides about succession |
| 206 | of receiving it by a process. If you want to compile and run |
| 207 | programs written e.g. for Solaris with use of its POSIX message |
| 208 | queues (functions mq_*) say Y here. |
| 209 | |
| 210 | POSIX message queues are visible as a filesystem called 'mqueue' |
| 211 | and can be mounted somewhere if you want to do filesystem |
| 212 | operations on message queues. |
| 213 | |
| 214 | If unsure, say Y. |
| 215 | |
| 216 | config POSIX_MQUEUE_SYSCTL |
| 217 | bool |
| 218 | depends on POSIX_MQUEUE |
| 219 | depends on SYSCTL |
| 220 | default y |
| 221 | |
| 222 | config BSD_PROCESS_ACCT |
| 223 | bool "BSD Process Accounting" |
| 224 | help |
| 225 | If you say Y here, a user level program will be able to instruct the |
| 226 | kernel (via a special system call) to write process accounting |
| 227 | information to a file: whenever a process exits, information about |
| 228 | that process will be appended to the file by the kernel. The |
| 229 | information includes things such as creation time, owning user, |
| 230 | command name, memory usage, controlling terminal etc. (the complete |
| 231 | list is in the struct acct in <file:include/linux/acct.h>). It is |
| 232 | up to the user level program to do useful things with this |
| 233 | information. This is generally a good idea, so say Y. |
| 234 | |
| 235 | config BSD_PROCESS_ACCT_V3 |
| 236 | bool "BSD Process Accounting version 3 file format" |
| 237 | depends on BSD_PROCESS_ACCT |
| 238 | default n |
| 239 | help |
| 240 | If you say Y here, the process accounting information is written |
| 241 | in a new file format that also logs the process IDs of each |
| 242 | process and it's parent. Note that this file format is incompatible |
| 243 | with previous v0/v1/v2 file formats, so you will need updated tools |
| 244 | for processing it. A preliminary version of these tools is available |
| 245 | at <http://www.gnu.org/software/acct/>. |
| 246 | |
| 247 | config TASKSTATS |
| 248 | bool "Export task/process statistics through netlink (EXPERIMENTAL)" |
| 249 | depends on NET |
| 250 | default n |
| 251 | help |
| 252 | Export selected statistics for tasks/processes through the |
| 253 | generic netlink interface. Unlike BSD process accounting, the |
| 254 | statistics are available during the lifetime of tasks/processes as |
| 255 | responses to commands. Like BSD accounting, they are sent to user |
| 256 | space on task exit. |
| 257 | |
| 258 | Say N if unsure. |
| 259 | |
| 260 | config TASK_DELAY_ACCT |
| 261 | bool "Enable per-task delay accounting (EXPERIMENTAL)" |
| 262 | depends on TASKSTATS |
| 263 | help |
| 264 | Collect information on time spent by a task waiting for system |
| 265 | resources like cpu, synchronous block I/O completion and swapping |
| 266 | in pages. Such statistics can help in setting a task's priorities |
| 267 | relative to other tasks for cpu, io, rss limits etc. |
| 268 | |
| 269 | Say N if unsure. |
| 270 | |
| 271 | config TASK_XACCT |
| 272 | bool "Enable extended accounting over taskstats (EXPERIMENTAL)" |
| 273 | depends on TASKSTATS |
| 274 | help |
| 275 | Collect extended task accounting data and send the data |
| 276 | to userland for processing over the taskstats interface. |
| 277 | |
| 278 | Say N if unsure. |
| 279 | |
| 280 | config TASK_IO_ACCOUNTING |
| 281 | bool "Enable per-task storage I/O accounting (EXPERIMENTAL)" |
| 282 | depends on TASK_XACCT |
| 283 | help |
| 284 | Collect information on the number of bytes of storage I/O which this |
| 285 | task has caused. |
| 286 | |
| 287 | Say N if unsure. |
| 288 | |
| 289 | config AUDIT |
| 290 | bool "Auditing support" |
| 291 | depends on NET |
| 292 | help |
| 293 | Enable auditing infrastructure that can be used with another |
| 294 | kernel subsystem, such as SELinux (which requires this for |
| 295 | logging of avc messages output). Does not do system-call |
| 296 | auditing without CONFIG_AUDITSYSCALL. |
| 297 | |
| 298 | config AUDITSYSCALL |
| 299 | bool "Enable system-call auditing support" |
| 300 | depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64|| SUPERH) |
| 301 | default y if SECURITY_SELINUX |
| 302 | help |
| 303 | Enable low-overhead system-call auditing infrastructure that |
| 304 | can be used independently or with another kernel subsystem, |
| 305 | such as SELinux. To use audit's filesystem watch feature, please |
| 306 | ensure that INOTIFY is configured. |
| 307 | |
| 308 | config AUDIT_TREE |
| 309 | def_bool y |
| 310 | depends on AUDITSYSCALL |
| 311 | select INOTIFY |
| 312 | |
| 313 | menu "RCU Subsystem" |
| 314 | |
| 315 | choice |
| 316 | prompt "RCU Implementation" |
| 317 | default TREE_RCU |
| 318 | |
| 319 | config TREE_RCU |
| 320 | bool "Tree-based hierarchical RCU" |
| 321 | help |
| 322 | This option selects the RCU implementation that is |
| 323 | designed for very large SMP system with hundreds or |
| 324 | thousands of CPUs. It also scales down nicely to |
| 325 | smaller systems. |
| 326 | |
| 327 | config TREE_PREEMPT_RCU |
| 328 | bool "Preemptable tree-based hierarchical RCU" |
| 329 | depends on PREEMPT |
| 330 | help |
| 331 | This option selects the RCU implementation that is |
| 332 | designed for very large SMP systems with hundreds or |
| 333 | thousands of CPUs, but for which real-time response |
| 334 | is also required. |
| 335 | |
| 336 | endchoice |
| 337 | |
| 338 | config RCU_TRACE |
| 339 | bool "Enable tracing for RCU" |
| 340 | depends on TREE_RCU || TREE_PREEMPT_RCU |
| 341 | help |
| 342 | This option provides tracing in RCU which presents stats |
| 343 | in debugfs for debugging RCU implementation. |
| 344 | |
| 345 | Say Y here if you want to enable RCU tracing |
| 346 | Say N if you are unsure. |
| 347 | |
| 348 | config RCU_FANOUT |
| 349 | int "Tree-based hierarchical RCU fanout value" |
| 350 | range 2 64 if 64BIT |
| 351 | range 2 32 if !64BIT |
| 352 | depends on TREE_RCU || TREE_PREEMPT_RCU |
| 353 | default 64 if 64BIT |
| 354 | default 32 if !64BIT |
| 355 | help |
| 356 | This option controls the fanout of hierarchical implementations |
| 357 | of RCU, allowing RCU to work efficiently on machines with |
| 358 | large numbers of CPUs. This value must be at least the cube |
| 359 | root of NR_CPUS, which allows NR_CPUS up to 32,768 for 32-bit |
| 360 | systems and up to 262,144 for 64-bit systems. |
| 361 | |
| 362 | Select a specific number if testing RCU itself. |
| 363 | Take the default if unsure. |
| 364 | |
| 365 | config RCU_FANOUT_EXACT |
| 366 | bool "Disable tree-based hierarchical RCU auto-balancing" |
| 367 | depends on TREE_RCU || TREE_PREEMPT_RCU |
| 368 | default n |
| 369 | help |
| 370 | This option forces use of the exact RCU_FANOUT value specified, |
| 371 | regardless of imbalances in the hierarchy. This is useful for |
| 372 | testing RCU itself, and might one day be useful on systems with |
| 373 | strong NUMA behavior. |
| 374 | |
| 375 | Without RCU_FANOUT_EXACT, the code will balance the hierarchy. |
| 376 | |
| 377 | Say N if unsure. |
| 378 | |
| 379 | config TREE_RCU_TRACE |
| 380 | def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU ) |
| 381 | select DEBUG_FS |
| 382 | help |
| 383 | This option provides tracing for the TREE_RCU and |
| 384 | TREE_PREEMPT_RCU implementations, permitting Makefile to |
| 385 | trivially select kernel/rcutree_trace.c. |
| 386 | |
| 387 | endmenu # "RCU Subsystem" |
| 388 | |
| 389 | config IKCONFIG |
| 390 | tristate "Kernel .config support" |
| 391 | ---help--- |
| 392 | This option enables the complete Linux kernel ".config" file |
| 393 | contents to be saved in the kernel. It provides documentation |
| 394 | of which kernel options are used in a running kernel or in an |
| 395 | on-disk kernel. This information can be extracted from the kernel |
| 396 | image file with the script scripts/extract-ikconfig and used as |
| 397 | input to rebuild the current kernel or to build another kernel. |
| 398 | It can also be extracted from a running kernel by reading |
| 399 | /proc/config.gz if enabled (below). |
| 400 | |
| 401 | config IKCONFIG_PROC |
| 402 | bool "Enable access to .config through /proc/config.gz" |
| 403 | depends on IKCONFIG && PROC_FS |
| 404 | ---help--- |
| 405 | This option enables access to the kernel configuration file |
| 406 | through /proc/config.gz. |
| 407 | |
| 408 | config LOG_BUF_SHIFT |
| 409 | int "Kernel log buffer size (16 => 64KB, 17 => 128KB)" |
| 410 | range 12 21 |
| 411 | default 17 |
| 412 | help |
| 413 | Select kernel log buffer size as a power of 2. |
| 414 | Examples: |
| 415 | 17 => 128 KB |
| 416 | 16 => 64 KB |
| 417 | 15 => 32 KB |
| 418 | 14 => 16 KB |
| 419 | 13 => 8 KB |
| 420 | 12 => 4 KB |
| 421 | |
| 422 | # |
| 423 | # Architectures with an unreliable sched_clock() should select this: |
| 424 | # |
| 425 | config HAVE_UNSTABLE_SCHED_CLOCK |
| 426 | bool |
| 427 | |
| 428 | config GROUP_SCHED |
| 429 | bool "Group CPU scheduler" |
| 430 | depends on EXPERIMENTAL |
| 431 | default n |
| 432 | help |
| 433 | This feature lets CPU scheduler recognize task groups and control CPU |
| 434 | bandwidth allocation to such task groups. |
| 435 | In order to create a group from arbitrary set of processes, use |
| 436 | CONFIG_CGROUPS. (See Control Group support.) |
| 437 | |
| 438 | config FAIR_GROUP_SCHED |
| 439 | bool "Group scheduling for SCHED_OTHER" |
| 440 | depends on GROUP_SCHED |
| 441 | default GROUP_SCHED |
| 442 | |
| 443 | config RT_GROUP_SCHED |
| 444 | bool "Group scheduling for SCHED_RR/FIFO" |
| 445 | depends on EXPERIMENTAL |
| 446 | depends on GROUP_SCHED |
| 447 | default n |
| 448 | help |
| 449 | This feature lets you explicitly allocate real CPU bandwidth |
| 450 | to users or control groups (depending on the "Basis for grouping tasks" |
| 451 | setting below. If enabled, it will also make it impossible to |
| 452 | schedule realtime tasks for non-root users until you allocate |
| 453 | realtime bandwidth for them. |
| 454 | See Documentation/scheduler/sched-rt-group.txt for more information. |
| 455 | |
| 456 | choice |
| 457 | depends on GROUP_SCHED |
| 458 | prompt "Basis for grouping tasks" |
| 459 | default USER_SCHED |
| 460 | |
| 461 | config USER_SCHED |
| 462 | bool "user id" |
| 463 | help |
| 464 | This option will choose userid as the basis for grouping |
| 465 | tasks, thus providing equal CPU bandwidth to each user. |
| 466 | |
| 467 | config CGROUP_SCHED |
| 468 | bool "Control groups" |
| 469 | depends on CGROUPS |
| 470 | help |
| 471 | This option allows you to create arbitrary task groups |
| 472 | using the "cgroup" pseudo filesystem and control |
| 473 | the cpu bandwidth allocated to each such task group. |
| 474 | Refer to Documentation/cgroups/cgroups.txt for more |
| 475 | information on "cgroup" pseudo filesystem. |
| 476 | |
| 477 | endchoice |
| 478 | |
| 479 | menuconfig CGROUPS |
| 480 | boolean "Control Group support" |
| 481 | help |
| 482 | This option adds support for grouping sets of processes together, for |
| 483 | use with process control subsystems such as Cpusets, CFS, memory |
| 484 | controls or device isolation. |
| 485 | See |
| 486 | - Documentation/scheduler/sched-design-CFS.txt (CFS) |
| 487 | - Documentation/cgroups/ (features for grouping, isolation |
| 488 | and resource control) |
| 489 | |
| 490 | Say N if unsure. |
| 491 | |
| 492 | if CGROUPS |
| 493 | |
| 494 | config CGROUP_DEBUG |
| 495 | bool "Example debug cgroup subsystem" |
| 496 | depends on CGROUPS |
| 497 | default n |
| 498 | help |
| 499 | This option enables a simple cgroup subsystem that |
| 500 | exports useful debugging information about the cgroups |
| 501 | framework. |
| 502 | |
| 503 | Say N if unsure. |
| 504 | |
| 505 | config CGROUP_NS |
| 506 | bool "Namespace cgroup subsystem" |
| 507 | depends on CGROUPS |
| 508 | help |
| 509 | Provides a simple namespace cgroup subsystem to |
| 510 | provide hierarchical naming of sets of namespaces, |
| 511 | for instance virtual servers and checkpoint/restart |
| 512 | jobs. |
| 513 | |
| 514 | config CGROUP_FREEZER |
| 515 | bool "Freezer cgroup subsystem" |
| 516 | depends on CGROUPS |
| 517 | help |
| 518 | Provides a way to freeze and unfreeze all tasks in a |
| 519 | cgroup. |
| 520 | |
| 521 | config CGROUP_DEVICE |
| 522 | bool "Device controller for cgroups" |
| 523 | depends on CGROUPS && EXPERIMENTAL |
| 524 | help |
| 525 | Provides a cgroup implementing whitelists for devices which |
| 526 | a process in the cgroup can mknod or open. |
| 527 | |
| 528 | config CPUSETS |
| 529 | bool "Cpuset support" |
| 530 | depends on CGROUPS |
| 531 | help |
| 532 | This option will let you create and manage CPUSETs which |
| 533 | allow dynamically partitioning a system into sets of CPUs and |
| 534 | Memory Nodes and assigning tasks to run only within those sets. |
| 535 | This is primarily useful on large SMP or NUMA systems. |
| 536 | |
| 537 | Say N if unsure. |
| 538 | |
| 539 | config PROC_PID_CPUSET |
| 540 | bool "Include legacy /proc/<pid>/cpuset file" |
| 541 | depends on CPUSETS |
| 542 | default y |
| 543 | |
| 544 | config CGROUP_CPUACCT |
| 545 | bool "Simple CPU accounting cgroup subsystem" |
| 546 | depends on CGROUPS |
| 547 | help |
| 548 | Provides a simple Resource Controller for monitoring the |
| 549 | total CPU consumed by the tasks in a cgroup. |
| 550 | |
| 551 | config RESOURCE_COUNTERS |
| 552 | bool "Resource counters" |
| 553 | help |
| 554 | This option enables controller independent resource accounting |
| 555 | infrastructure that works with cgroups. |
| 556 | depends on CGROUPS |
| 557 | |
| 558 | config CGROUP_MEM_RES_CTLR |
| 559 | bool "Memory Resource Controller for Control Groups" |
| 560 | depends on CGROUPS && RESOURCE_COUNTERS |
| 561 | select MM_OWNER |
| 562 | help |
| 563 | Provides a memory resource controller that manages both anonymous |
| 564 | memory and page cache. (See Documentation/cgroups/memory.txt) |
| 565 | |
| 566 | Note that setting this option increases fixed memory overhead |
| 567 | associated with each page of memory in the system. By this, |
| 568 | 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory |
| 569 | usage tracking struct at boot. Total amount of this is printed out |
| 570 | at boot. |
| 571 | |
| 572 | Only enable when you're ok with these trade offs and really |
| 573 | sure you need the memory resource controller. Even when you enable |
| 574 | this, you can set "cgroup_disable=memory" at your boot option to |
| 575 | disable memory resource controller and you can avoid overheads. |
| 576 | (and lose benefits of memory resource controller) |
| 577 | |
| 578 | This config option also selects MM_OWNER config option, which |
| 579 | could in turn add some fork/exit overhead. |
| 580 | |
| 581 | config CGROUP_MEM_RES_CTLR_SWAP |
| 582 | bool "Memory Resource Controller Swap Extension(EXPERIMENTAL)" |
| 583 | depends on CGROUP_MEM_RES_CTLR && SWAP && EXPERIMENTAL |
| 584 | help |
| 585 | Add swap management feature to memory resource controller. When you |
| 586 | enable this, you can limit mem+swap usage per cgroup. In other words, |
| 587 | when you disable this, memory resource controller has no cares to |
| 588 | usage of swap...a process can exhaust all of the swap. This extension |
| 589 | is useful when you want to avoid exhaustion swap but this itself |
| 590 | adds more overheads and consumes memory for remembering information. |
| 591 | Especially if you use 32bit system or small memory system, please |
| 592 | be careful about enabling this. When memory resource controller |
| 593 | is disabled by boot option, this will be automatically disabled and |
| 594 | there will be no overhead from this. Even when you set this config=y, |
| 595 | if boot option "noswapaccount" is set, swap will not be accounted. |
| 596 | Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page |
| 597 | size is 4096bytes, 512k per 1Gbytes of swap. |
| 598 | |
| 599 | endif # CGROUPS |
| 600 | |
| 601 | config MM_OWNER |
| 602 | bool |
| 603 | |
| 604 | config SYSFS_DEPRECATED |
| 605 | bool |
| 606 | |
| 607 | config SYSFS_DEPRECATED_V2 |
| 608 | bool "remove sysfs features which may confuse old userspace tools" |
| 609 | depends on SYSFS |
| 610 | default n |
| 611 | select SYSFS_DEPRECATED |
| 612 | help |
| 613 | This option switches the layout of sysfs to the deprecated |
| 614 | version. Do not use it on recent distributions. |
| 615 | |
| 616 | The current sysfs layout features a unified device tree at |
| 617 | /sys/devices/, which is able to express a hierarchy between |
| 618 | class devices. If the deprecated option is set to Y, the |
| 619 | unified device tree is split into a bus device tree at |
| 620 | /sys/devices/ and several individual class device trees at |
| 621 | /sys/class/. The class and bus devices will be connected by |
| 622 | "<subsystem>:<name>" and the "device" links. The "block" |
| 623 | class devices, will not show up in /sys/class/block/. Some |
| 624 | subsystems will suppress the creation of some devices which |
| 625 | depend on the unified device tree. |
| 626 | |
| 627 | This option is not a pure compatibility option that can |
| 628 | be safely enabled on newer distributions. It will change the |
| 629 | layout of sysfs to the non-extensible deprecated version, |
| 630 | and disable some features, which can not be exported without |
| 631 | confusing older userspace tools. Since 2007/2008 all major |
| 632 | distributions do not enable this option, and ship no tools which |
| 633 | depend on the deprecated layout or this option. |
| 634 | |
| 635 | If you are using a new kernel on an older distribution, or use |
| 636 | older userspace tools, you might need to say Y here. Do not say Y, |
| 637 | if the original kernel, that came with your distribution, has |
| 638 | this option set to N. |
| 639 | |
| 640 | config RELAY |
| 641 | bool "Kernel->user space relay support (formerly relayfs)" |
| 642 | help |
| 643 | This option enables support for relay interface support in |
| 644 | certain file systems (such as debugfs). |
| 645 | It is designed to provide an efficient mechanism for tools and |
| 646 | facilities to relay large amounts of data from kernel space to |
| 647 | user space. |
| 648 | |
| 649 | If unsure, say N. |
| 650 | |
| 651 | config NAMESPACES |
| 652 | bool "Namespaces support" if EMBEDDED |
| 653 | default !EMBEDDED |
| 654 | help |
| 655 | Provides the way to make tasks work with different objects using |
| 656 | the same id. For example same IPC id may refer to different objects |
| 657 | or same user id or pid may refer to different tasks when used in |
| 658 | different namespaces. |
| 659 | |
| 660 | config UTS_NS |
| 661 | bool "UTS namespace" |
| 662 | depends on NAMESPACES |
| 663 | help |
| 664 | In this namespace tasks see different info provided with the |
| 665 | uname() system call |
| 666 | |
| 667 | config IPC_NS |
| 668 | bool "IPC namespace" |
| 669 | depends on NAMESPACES && (SYSVIPC || POSIX_MQUEUE) |
| 670 | help |
| 671 | In this namespace tasks work with IPC ids which correspond to |
| 672 | different IPC objects in different namespaces. |
| 673 | |
| 674 | config USER_NS |
| 675 | bool "User namespace (EXPERIMENTAL)" |
| 676 | depends on NAMESPACES && EXPERIMENTAL |
| 677 | help |
| 678 | This allows containers, i.e. vservers, to use user namespaces |
| 679 | to provide different user info for different servers. |
| 680 | If unsure, say N. |
| 681 | |
| 682 | config PID_NS |
| 683 | bool "PID Namespaces (EXPERIMENTAL)" |
| 684 | default n |
| 685 | depends on NAMESPACES && EXPERIMENTAL |
| 686 | help |
| 687 | Support process id namespaces. This allows having multiple |
| 688 | processes with the same pid as long as they are in different |
| 689 | pid namespaces. This is a building block of containers. |
| 690 | |
| 691 | Unless you want to work with an experimental feature |
| 692 | say N here. |
| 693 | |
| 694 | config NET_NS |
| 695 | bool "Network namespace" |
| 696 | default n |
| 697 | depends on NAMESPACES && EXPERIMENTAL && NET |
| 698 | help |
| 699 | Allow user space to create what appear to be multiple instances |
| 700 | of the network stack. |
| 701 | |
| 702 | config BLK_DEV_INITRD |
| 703 | bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support" |
| 704 | depends on BROKEN || !FRV |
| 705 | help |
| 706 | The initial RAM filesystem is a ramfs which is loaded by the |
| 707 | boot loader (loadlin or lilo) and that is mounted as root |
| 708 | before the normal boot procedure. It is typically used to |
| 709 | load modules needed to mount the "real" root file system, |
| 710 | etc. See <file:Documentation/initrd.txt> for details. |
| 711 | |
| 712 | If RAM disk support (BLK_DEV_RAM) is also included, this |
| 713 | also enables initial RAM disk (initrd) support and adds |
| 714 | 15 Kbytes (more on some other architectures) to the kernel size. |
| 715 | |
| 716 | If unsure say Y. |
| 717 | |
| 718 | if BLK_DEV_INITRD |
| 719 | |
| 720 | source "usr/Kconfig" |
| 721 | |
| 722 | endif |
| 723 | |
| 724 | config CC_OPTIMIZE_FOR_SIZE |
| 725 | bool "Optimize for size" |
| 726 | default y |
| 727 | help |
| 728 | Enabling this option will pass "-Os" instead of "-O2" to gcc |
| 729 | resulting in a smaller kernel. |
| 730 | |
| 731 | If unsure, say Y. |
| 732 | |
| 733 | config SYSCTL |
| 734 | bool |
| 735 | |
| 736 | config ANON_INODES |
| 737 | bool |
| 738 | |
| 739 | menuconfig EMBEDDED |
| 740 | bool "Configure standard kernel features (for small systems)" |
| 741 | help |
| 742 | This option allows certain base kernel options and settings |
| 743 | to be disabled or tweaked. This is for specialized |
| 744 | environments which can tolerate a "non-standard" kernel. |
| 745 | Only use this if you really know what you are doing. |
| 746 | |
| 747 | config UID16 |
| 748 | bool "Enable 16-bit UID system calls" if EMBEDDED |
| 749 | depends on ARM || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && COMPAT) || UML || (X86_64 && IA32_EMULATION) |
| 750 | default y |
| 751 | help |
| 752 | This enables the legacy 16-bit UID syscall wrappers. |
| 753 | |
| 754 | config SYSCTL_SYSCALL |
| 755 | bool "Sysctl syscall support" if EMBEDDED |
| 756 | default y |
| 757 | select SYSCTL |
| 758 | ---help--- |
| 759 | sys_sysctl uses binary paths that have been found challenging |
| 760 | to properly maintain and use. The interface in /proc/sys |
| 761 | using paths with ascii names is now the primary path to this |
| 762 | information. |
| 763 | |
| 764 | Almost nothing using the binary sysctl interface so if you are |
| 765 | trying to save some space it is probably safe to disable this, |
| 766 | making your kernel marginally smaller. |
| 767 | |
| 768 | If unsure say Y here. |
| 769 | |
| 770 | config KALLSYMS |
| 771 | bool "Load all symbols for debugging/ksymoops" if EMBEDDED |
| 772 | default y |
| 773 | help |
| 774 | Say Y here to let the kernel print out symbolic crash information and |
| 775 | symbolic stack backtraces. This increases the size of the kernel |
| 776 | somewhat, as all symbols have to be loaded into the kernel image. |
| 777 | |
| 778 | config KALLSYMS_ALL |
| 779 | bool "Include all symbols in kallsyms" |
| 780 | depends on DEBUG_KERNEL && KALLSYMS |
| 781 | help |
| 782 | Normally kallsyms only contains the symbols of functions, for nicer |
| 783 | OOPS messages. Some debuggers can use kallsyms for other |
| 784 | symbols too: say Y here to include all symbols, if you need them |
| 785 | and you don't care about adding 300k to the size of your kernel. |
| 786 | |
| 787 | Say N. |
| 788 | |
| 789 | config KALLSYMS_EXTRA_PASS |
| 790 | bool "Do an extra kallsyms pass" |
| 791 | depends on KALLSYMS |
| 792 | help |
| 793 | If kallsyms is not working correctly, the build will fail with |
| 794 | inconsistent kallsyms data. If that occurs, log a bug report and |
| 795 | turn on KALLSYMS_EXTRA_PASS which should result in a stable build. |
| 796 | Always say N here unless you find a bug in kallsyms, which must be |
| 797 | reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while |
| 798 | you wait for kallsyms to be fixed. |
| 799 | |
| 800 | |
| 801 | config HOTPLUG |
| 802 | bool "Support for hot-pluggable devices" if EMBEDDED |
| 803 | default y |
| 804 | help |
| 805 | This option is provided for the case where no hotplug or uevent |
| 806 | capabilities is wanted by the kernel. You should only consider |
| 807 | disabling this option for embedded systems that do not use modules, a |
| 808 | dynamic /dev tree, or dynamic device discovery. Just say Y. |
| 809 | |
| 810 | config PRINTK |
| 811 | default y |
| 812 | bool "Enable support for printk" if EMBEDDED |
| 813 | help |
| 814 | This option enables normal printk support. Removing it |
| 815 | eliminates most of the message strings from the kernel image |
| 816 | and makes the kernel more or less silent. As this makes it |
| 817 | very difficult to diagnose system problems, saying N here is |
| 818 | strongly discouraged. |
| 819 | |
| 820 | config BUG |
| 821 | bool "BUG() support" if EMBEDDED |
| 822 | default y |
| 823 | help |
| 824 | Disabling this option eliminates support for BUG and WARN, reducing |
| 825 | the size of your kernel image and potentially quietly ignoring |
| 826 | numerous fatal conditions. You should only consider disabling this |
| 827 | option for embedded systems with no facilities for reporting errors. |
| 828 | Just say Y. |
| 829 | |
| 830 | config ELF_CORE |
| 831 | default y |
| 832 | bool "Enable ELF core dumps" if EMBEDDED |
| 833 | help |
| 834 | Enable support for generating core dumps. Disabling saves about 4k. |
| 835 | |
| 836 | config PCSPKR_PLATFORM |
| 837 | bool "Enable PC-Speaker support" if EMBEDDED |
| 838 | depends on ALPHA || X86 || MIPS || PPC_PREP || PPC_CHRP || PPC_PSERIES |
| 839 | default y |
| 840 | help |
| 841 | This option allows to disable the internal PC-Speaker |
| 842 | support, saving some memory. |
| 843 | |
| 844 | config BASE_FULL |
| 845 | default y |
| 846 | bool "Enable full-sized data structures for core" if EMBEDDED |
| 847 | help |
| 848 | Disabling this option reduces the size of miscellaneous core |
| 849 | kernel data structures. This saves memory on small machines, |
| 850 | but may reduce performance. |
| 851 | |
| 852 | config FUTEX |
| 853 | bool "Enable futex support" if EMBEDDED |
| 854 | default y |
| 855 | select RT_MUTEXES |
| 856 | help |
| 857 | Disabling this option will cause the kernel to be built without |
| 858 | support for "fast userspace mutexes". The resulting kernel may not |
| 859 | run glibc-based applications correctly. |
| 860 | |
| 861 | config EPOLL |
| 862 | bool "Enable eventpoll support" if EMBEDDED |
| 863 | default y |
| 864 | select ANON_INODES |
| 865 | help |
| 866 | Disabling this option will cause the kernel to be built without |
| 867 | support for epoll family of system calls. |
| 868 | |
| 869 | config SIGNALFD |
| 870 | bool "Enable signalfd() system call" if EMBEDDED |
| 871 | select ANON_INODES |
| 872 | default y |
| 873 | help |
| 874 | Enable the signalfd() system call that allows to receive signals |
| 875 | on a file descriptor. |
| 876 | |
| 877 | If unsure, say Y. |
| 878 | |
| 879 | config TIMERFD |
| 880 | bool "Enable timerfd() system call" if EMBEDDED |
| 881 | select ANON_INODES |
| 882 | default y |
| 883 | help |
| 884 | Enable the timerfd() system call that allows to receive timer |
| 885 | events on a file descriptor. |
| 886 | |
| 887 | If unsure, say Y. |
| 888 | |
| 889 | config EVENTFD |
| 890 | bool "Enable eventfd() system call" if EMBEDDED |
| 891 | select ANON_INODES |
| 892 | default y |
| 893 | help |
| 894 | Enable the eventfd() system call that allows to receive both |
| 895 | kernel notification (ie. KAIO) or userspace notifications. |
| 896 | |
| 897 | If unsure, say Y. |
| 898 | |
| 899 | config SHMEM |
| 900 | bool "Use full shmem filesystem" if EMBEDDED |
| 901 | default y |
| 902 | depends on MMU |
| 903 | help |
| 904 | The shmem is an internal filesystem used to manage shared memory. |
| 905 | It is backed by swap and manages resource limits. It is also exported |
| 906 | to userspace as tmpfs if TMPFS is enabled. Disabling this |
| 907 | option replaces shmem and tmpfs with the much simpler ramfs code, |
| 908 | which may be appropriate on small systems without swap. |
| 909 | |
| 910 | config AIO |
| 911 | bool "Enable AIO support" if EMBEDDED |
| 912 | default y |
| 913 | help |
| 914 | This option enables POSIX asynchronous I/O which may by used |
| 915 | by some high performance threaded applications. Disabling |
| 916 | this option saves about 7k. |
| 917 | |
| 918 | config HAVE_PERF_EVENTS |
| 919 | bool |
| 920 | help |
| 921 | See tools/perf/design.txt for details. |
| 922 | |
| 923 | menu "Kernel Performance Events And Counters" |
| 924 | |
| 925 | config PERF_EVENTS |
| 926 | bool "Kernel performance events and counters" |
| 927 | default y if (PROFILING || PERF_COUNTERS) |
| 928 | depends on HAVE_PERF_EVENTS |
| 929 | select ANON_INODES |
| 930 | help |
| 931 | Enable kernel support for various performance events provided |
| 932 | by software and hardware. |
| 933 | |
| 934 | Software events are supported either build-in or via the |
| 935 | use of generic tracepoints. |
| 936 | |
| 937 | Most modern CPUs support performance events via performance |
| 938 | counter registers. These registers count the number of certain |
| 939 | types of hw events: such as instructions executed, cachemisses |
| 940 | suffered, or branches mis-predicted - without slowing down the |
| 941 | kernel or applications. These registers can also trigger interrupts |
| 942 | when a threshold number of events have passed - and can thus be |
| 943 | used to profile the code that runs on that CPU. |
| 944 | |
| 945 | The Linux Performance Event subsystem provides an abstraction of |
| 946 | these software and hardware cevent apabilities, available via a |
| 947 | system call and used by the "perf" utility in tools/perf/. It |
| 948 | provides per task and per CPU counters, and it provides event |
| 949 | capabilities on top of those. |
| 950 | |
| 951 | Say Y if unsure. |
| 952 | |
| 953 | config EVENT_PROFILE |
| 954 | bool "Tracepoint profiling sources" |
| 955 | depends on PERF_EVENTS && EVENT_TRACING |
| 956 | default y |
| 957 | help |
| 958 | Allow the use of tracepoints as software performance events. |
| 959 | |
| 960 | When this is enabled, you can create perf events based on |
| 961 | tracepoints using PERF_TYPE_TRACEPOINT and the tracepoint ID |
| 962 | found in debugfs://tracing/events/*/*/id. (The -e/--events |
| 963 | option to the perf tool can parse and interpret symbolic |
| 964 | tracepoints, in the subsystem:tracepoint_name format.) |
| 965 | |
| 966 | config PERF_COUNTERS |
| 967 | bool "Kernel performance counters (old config option)" |
| 968 | depends on HAVE_PERF_EVENTS |
| 969 | help |
| 970 | This config has been obsoleted by the PERF_EVENTS |
| 971 | config option - please see that one for details. |
| 972 | |
| 973 | It has no effect on the kernel whether you enable |
| 974 | it or not, it is a compatibility placeholder. |
| 975 | |
| 976 | Say N if unsure. |
| 977 | |
| 978 | endmenu |
| 979 | |
| 980 | config VM_EVENT_COUNTERS |
| 981 | default y |
| 982 | bool "Enable VM event counters for /proc/vmstat" if EMBEDDED |
| 983 | help |
| 984 | VM event counters are needed for event counts to be shown. |
| 985 | This option allows the disabling of the VM event counters |
| 986 | on EMBEDDED systems. /proc/vmstat will only show page counts |
| 987 | if VM event counters are disabled. |
| 988 | |
| 989 | config PCI_QUIRKS |
| 990 | default y |
| 991 | bool "Enable PCI quirk workarounds" if EMBEDDED |
| 992 | depends on PCI |
| 993 | help |
| 994 | This enables workarounds for various PCI chipset |
| 995 | bugs/quirks. Disable this only if your target machine is |
| 996 | unaffected by PCI quirks. |
| 997 | |
| 998 | config SLUB_DEBUG |
| 999 | default y |
| 1000 | bool "Enable SLUB debugging support" if EMBEDDED |
| 1001 | depends on SLUB && SYSFS |
| 1002 | help |
| 1003 | SLUB has extensive debug support features. Disabling these can |
| 1004 | result in significant savings in code size. This also disables |
| 1005 | SLUB sysfs support. /sys/slab will not exist and there will be |
| 1006 | no support for cache validation etc. |
| 1007 | |
| 1008 | config STRIP_ASM_SYMS |
| 1009 | bool "Strip assembler-generated symbols during link" |
| 1010 | default n |
| 1011 | help |
| 1012 | Strip internal assembler-generated symbols during a link (symbols |
| 1013 | that look like '.Lxxx') so they don't pollute the output of |
| 1014 | get_wchan() and suchlike. |
| 1015 | |
| 1016 | config COMPAT_BRK |
| 1017 | bool "Disable heap randomization" |
| 1018 | default y |
| 1019 | help |
| 1020 | Randomizing heap placement makes heap exploits harder, but it |
| 1021 | also breaks ancient binaries (including anything libc5 based). |
| 1022 | This option changes the bootup default to heap randomization |
| 1023 | disabled, and can be overridden at runtime by setting |
| 1024 | /proc/sys/kernel/randomize_va_space to 2. |
| 1025 | |
| 1026 | On non-ancient distros (post-2000 ones) N is usually a safe choice. |
| 1027 | |
| 1028 | choice |
| 1029 | prompt "Choose SLAB allocator" |
| 1030 | default SLUB |
| 1031 | help |
| 1032 | This option allows to select a slab allocator. |
| 1033 | |
| 1034 | config SLAB |
| 1035 | bool "SLAB" |
| 1036 | help |
| 1037 | The regular slab allocator that is established and known to work |
| 1038 | well in all environments. It organizes cache hot objects in |
| 1039 | per cpu and per node queues. |
| 1040 | |
| 1041 | config SLUB |
| 1042 | bool "SLUB (Unqueued Allocator)" |
| 1043 | help |
| 1044 | SLUB is a slab allocator that minimizes cache line usage |
| 1045 | instead of managing queues of cached objects (SLAB approach). |
| 1046 | Per cpu caching is realized using slabs of objects instead |
| 1047 | of queues of objects. SLUB can use memory efficiently |
| 1048 | and has enhanced diagnostics. SLUB is the default choice for |
| 1049 | a slab allocator. |
| 1050 | |
| 1051 | config SLOB |
| 1052 | depends on EMBEDDED |
| 1053 | bool "SLOB (Simple Allocator)" |
| 1054 | help |
| 1055 | SLOB replaces the stock allocator with a drastically simpler |
| 1056 | allocator. SLOB is generally more space efficient but |
| 1057 | does not perform as well on large systems. |
| 1058 | |
| 1059 | endchoice |
| 1060 | |
| 1061 | config PROFILING |
| 1062 | bool "Profiling support (EXPERIMENTAL)" |
| 1063 | help |
| 1064 | Say Y here to enable the extended profiling support mechanisms used |
| 1065 | by profilers such as OProfile. |
| 1066 | |
| 1067 | # |
| 1068 | # Place an empty function call at each tracepoint site. Can be |
| 1069 | # dynamically changed for a probe function. |
| 1070 | # |
| 1071 | config TRACEPOINTS |
| 1072 | bool |
| 1073 | |
| 1074 | config MARKERS |
| 1075 | bool "Activate markers" |
| 1076 | select TRACEPOINTS |
| 1077 | help |
| 1078 | Place an empty function call at each marker site. Can be |
| 1079 | dynamically changed for a probe function. |
| 1080 | |
| 1081 | source "arch/Kconfig" |
| 1082 | |
| 1083 | config SLOW_WORK |
| 1084 | default n |
| 1085 | bool |
| 1086 | help |
| 1087 | The slow work thread pool provides a number of dynamically allocated |
| 1088 | threads that can be used by the kernel to perform operations that |
| 1089 | take a relatively long time. |
| 1090 | |
| 1091 | An example of this would be CacheFiles doing a path lookup followed |
| 1092 | by a series of mkdirs and a create call, all of which have to touch |
| 1093 | disk. |
| 1094 | |
| 1095 | See Documentation/slow-work.txt. |
| 1096 | |
| 1097 | endmenu # General setup |
| 1098 | |
| 1099 | config HAVE_GENERIC_DMA_COHERENT |
| 1100 | bool |
| 1101 | default n |
| 1102 | |
| 1103 | config SLABINFO |
| 1104 | bool |
| 1105 | depends on PROC_FS |
| 1106 | depends on SLAB || SLUB_DEBUG |
| 1107 | default y |
| 1108 | |
| 1109 | config RT_MUTEXES |
| 1110 | boolean |
| 1111 | |
| 1112 | config BASE_SMALL |
| 1113 | int |
| 1114 | default 0 if BASE_FULL |
| 1115 | default 1 if !BASE_FULL |
| 1116 | |
| 1117 | menuconfig MODULES |
| 1118 | bool "Enable loadable module support" |
| 1119 | help |
| 1120 | Kernel modules are small pieces of compiled code which can |
| 1121 | be inserted in the running kernel, rather than being |
| 1122 | permanently built into the kernel. You use the "modprobe" |
| 1123 | tool to add (and sometimes remove) them. If you say Y here, |
| 1124 | many parts of the kernel can be built as modules (by |
| 1125 | answering M instead of Y where indicated): this is most |
| 1126 | useful for infrequently used options which are not required |
| 1127 | for booting. For more information, see the man pages for |
| 1128 | modprobe, lsmod, modinfo, insmod and rmmod. |
| 1129 | |
| 1130 | If you say Y here, you will need to run "make |
| 1131 | modules_install" to put the modules under /lib/modules/ |
| 1132 | where modprobe can find them (you may need to be root to do |
| 1133 | this). |
| 1134 | |
| 1135 | If unsure, say Y. |
| 1136 | |
| 1137 | if MODULES |
| 1138 | |
| 1139 | config MODULE_FORCE_LOAD |
| 1140 | bool "Forced module loading" |
| 1141 | default n |
| 1142 | help |
| 1143 | Allow loading of modules without version information (ie. modprobe |
| 1144 | --force). Forced module loading sets the 'F' (forced) taint flag and |
| 1145 | is usually a really bad idea. |
| 1146 | |
| 1147 | config MODULE_UNLOAD |
| 1148 | bool "Module unloading" |
| 1149 | help |
| 1150 | Without this option you will not be able to unload any |
| 1151 | modules (note that some modules may not be unloadable |
| 1152 | anyway), which makes your kernel smaller, faster |
| 1153 | and simpler. If unsure, say Y. |
| 1154 | |
| 1155 | config MODULE_FORCE_UNLOAD |
| 1156 | bool "Forced module unloading" |
| 1157 | depends on MODULE_UNLOAD && EXPERIMENTAL |
| 1158 | help |
| 1159 | This option allows you to force a module to unload, even if the |
| 1160 | kernel believes it is unsafe: the kernel will remove the module |
| 1161 | without waiting for anyone to stop using it (using the -f option to |
| 1162 | rmmod). This is mainly for kernel developers and desperate users. |
| 1163 | If unsure, say N. |
| 1164 | |
| 1165 | config MODVERSIONS |
| 1166 | bool "Module versioning support" |
| 1167 | help |
| 1168 | Usually, you have to use modules compiled with your kernel. |
| 1169 | Saying Y here makes it sometimes possible to use modules |
| 1170 | compiled for different kernels, by adding enough information |
| 1171 | to the modules to (hopefully) spot any changes which would |
| 1172 | make them incompatible with the kernel you are running. If |
| 1173 | unsure, say N. |
| 1174 | |
| 1175 | config MODULE_SRCVERSION_ALL |
| 1176 | bool "Source checksum for all modules" |
| 1177 | help |
| 1178 | Modules which contain a MODULE_VERSION get an extra "srcversion" |
| 1179 | field inserted into their modinfo section, which contains a |
| 1180 | sum of the source files which made it. This helps maintainers |
| 1181 | see exactly which source was used to build a module (since |
| 1182 | others sometimes change the module source without updating |
| 1183 | the version). With this option, such a "srcversion" field |
| 1184 | will be created for all modules. If unsure, say N. |
| 1185 | |
| 1186 | endif # MODULES |
| 1187 | |
| 1188 | config INIT_ALL_POSSIBLE |
| 1189 | bool |
| 1190 | help |
| 1191 | Back when each arch used to define their own cpu_online_map and |
| 1192 | cpu_possible_map, some of them chose to initialize cpu_possible_map |
| 1193 | with all 1s, and others with all 0s. When they were centralised, |
| 1194 | it was better to provide this option than to break all the archs |
| 1195 | and have several arch maintainers pursuing me down dark alleys. |
| 1196 | |
| 1197 | config STOP_MACHINE |
| 1198 | bool |
| 1199 | default y |
| 1200 | depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU |
| 1201 | help |
| 1202 | Need stop_machine() primitive. |
| 1203 | |
| 1204 | source "block/Kconfig" |
| 1205 | |
| 1206 | config PREEMPT_NOTIFIERS |
| 1207 | bool |
| 1208 | |