Roman Zippel | 80daa56 | 2008-01-14 04:51:16 +0100 | [diff] [blame] | 1 | config ARCH |
| 2 | string |
| 3 | option env="ARCH" |
| 4 | |
| 5 | config KERNELVERSION |
| 6 | string |
| 7 | option env="KERNELVERSION" |
| 8 | |
Roman Zippel | face437 | 2006-06-08 22:12:45 -0700 | [diff] [blame] | 9 | config DEFCONFIG_LIST |
| 10 | string |
Paolo 'Blaisorblade' Giarrusso | b2670ea | 2006-10-19 23:28:23 -0700 | [diff] [blame] | 11 | depends on !UML |
Roman Zippel | face437 | 2006-06-08 22:12:45 -0700 | [diff] [blame] | 12 | option defconfig_list |
| 13 | default "/lib/modules/$UNAME_RELEASE/.config" |
| 14 | default "/etc/kernel-config" |
| 15 | default "/boot/config-$UNAME_RELEASE" |
Sam Ravnborg | 7353190 | 2008-05-25 23:03:18 +0200 | [diff] [blame] | 16 | default "$ARCH_DEFCONFIG" |
Roman Zippel | face437 | 2006-06-08 22:12:45 -0700 | [diff] [blame] | 17 | default "arch/$ARCH/defconfig" |
| 18 | |
Peter Oberparleiter | b99b87f | 2009-06-17 16:28:03 -0700 | [diff] [blame] | 19 | config CONSTRUCTORS |
| 20 | bool |
| 21 | depends on !UML |
| 22 | default y |
| 23 | |
Al Boldi | ff0cfc6 | 2007-07-31 00:39:23 -0700 | [diff] [blame] | 24 | menu "General setup" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | config BROKEN |
| 58 | bool |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 |
Adrian Bunk | dd673bc | 2006-06-30 01:55:51 -0700 | [diff] [blame] | 72 | default 32 if !UML |
| 73 | default 128 if UML |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | help |
Randy Dunlap | 34ad92c | 2005-10-30 15:01:46 -0800 | [diff] [blame] | 75 | Maximum of each of the number of arguments and environment |
| 76 | variables passed to init from the kernel command line. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | |
Roland McGrath | 8433646 | 2009-12-21 16:24:06 -0800 | [diff] [blame] | 79 | config CROSS_COMPILE |
| 80 | string "Cross-compiler tool prefix" |
| 81 | help |
| 82 | Same as running 'make CROSS_COMPILE=prefix-' but stored for |
| 83 | default make runs in this kernel build directory. You don't |
| 84 | need to set this unless you want the configured kernel build |
| 85 | directory to select the cross-compiler automatically. |
| 86 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 87 | config LOCALVERSION |
| 88 | string "Local version - append to kernel release" |
| 89 | help |
| 90 | Append an extra string to the end of your kernel version. |
| 91 | This will show up when you type uname, for example. |
| 92 | The string you set here will be appended after the contents of |
| 93 | any files with a filename matching localversion* in your |
| 94 | object and source tree, in that order. Your total string can |
| 95 | be a maximum of 64 characters. |
| 96 | |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 97 | config LOCALVERSION_AUTO |
| 98 | bool "Automatically append version information to the version string" |
| 99 | default y |
| 100 | help |
| 101 | This will try to automatically determine if the current tree is a |
Robert P. J. Day | 6e5a542 | 2007-05-01 23:08:11 +0200 | [diff] [blame] | 102 | release tree by looking for git tags that belong to the current |
| 103 | top of tree revision. |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 104 | |
| 105 | A string of the format -gxxxxxxxx will be added to the localversion |
Robert P. J. Day | 6e5a542 | 2007-05-01 23:08:11 +0200 | [diff] [blame] | 106 | if a git-based tree is found. The string generated by this will be |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 107 | appended after any matching localversion* files, and after the value |
Robert P. J. Day | 6e5a542 | 2007-05-01 23:08:11 +0200 | [diff] [blame] | 108 | set in CONFIG_LOCALVERSION. |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 109 | |
Robert P. J. Day | 6e5a542 | 2007-05-01 23:08:11 +0200 | [diff] [blame] | 110 | (The actual string used here is the first eight characters produced |
| 111 | by running the command: |
| 112 | |
| 113 | $ git rev-parse --verify HEAD |
| 114 | |
| 115 | which is done within the script "scripts/setlocalversion".) |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 116 | |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 117 | config HAVE_KERNEL_GZIP |
| 118 | bool |
| 119 | |
| 120 | config HAVE_KERNEL_BZIP2 |
| 121 | bool |
| 122 | |
| 123 | config HAVE_KERNEL_LZMA |
| 124 | bool |
| 125 | |
Albin Tonnerre | 7dd65fe | 2010-01-08 14:42:42 -0800 | [diff] [blame] | 126 | config HAVE_KERNEL_LZO |
| 127 | bool |
| 128 | |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 129 | choice |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 130 | prompt "Kernel compression mode" |
| 131 | default KERNEL_GZIP |
Albin Tonnerre | 7dd65fe | 2010-01-08 14:42:42 -0800 | [diff] [blame] | 132 | depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_LZO |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 133 | help |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 134 | The linux kernel is a kind of self-extracting executable. |
| 135 | Several compression algorithms are available, which differ |
| 136 | in efficiency, compression and decompression speed. |
| 137 | Compression speed is only relevant when building a kernel. |
| 138 | Decompression speed is relevant at each boot. |
| 139 | |
| 140 | If you have any problems with bzip2 or lzma compressed |
| 141 | kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older |
| 142 | version of this functionality (bzip2 only), for 2.4, was |
| 143 | supplied by Christian Ludwig) |
| 144 | |
| 145 | High compression options are mostly useful for users, who |
| 146 | are low on disk space (embedded systems), but for whom ram |
| 147 | size matters less. |
| 148 | |
| 149 | If in doubt, select 'gzip' |
| 150 | |
| 151 | config KERNEL_GZIP |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 152 | bool "Gzip" |
| 153 | depends on HAVE_KERNEL_GZIP |
| 154 | help |
Albin Tonnerre | 7dd65fe | 2010-01-08 14:42:42 -0800 | [diff] [blame] | 155 | The old and tried gzip compression. It provides a good balance |
| 156 | between compression ratio and decompression speed. |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 157 | |
| 158 | config KERNEL_BZIP2 |
| 159 | bool "Bzip2" |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 160 | depends on HAVE_KERNEL_BZIP2 |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 161 | help |
| 162 | Its compression ratio and speed is intermediate. |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 163 | Decompression speed is slowest among the three. The kernel |
| 164 | size is about 10% smaller with bzip2, in comparison to gzip. |
| 165 | Bzip2 uses a large amount of memory. For modern kernels you |
| 166 | will need at least 8MB RAM or more for booting. |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 167 | |
| 168 | config KERNEL_LZMA |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 169 | bool "LZMA" |
| 170 | depends on HAVE_KERNEL_LZMA |
| 171 | help |
| 172 | The most recent compression algorithm. |
| 173 | Its ratio is best, decompression speed is between the other |
| 174 | two. Compression is slowest. The kernel size is about 33% |
| 175 | smaller with LZMA in comparison to gzip. |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 176 | |
Albin Tonnerre | 7dd65fe | 2010-01-08 14:42:42 -0800 | [diff] [blame] | 177 | config KERNEL_LZO |
| 178 | bool "LZO" |
| 179 | depends on HAVE_KERNEL_LZO |
| 180 | help |
| 181 | Its compression ratio is the poorest among the 4. The kernel |
| 182 | size is about about 10% bigger than gzip; however its speed |
| 183 | (both compression and decompression) is the fastest. |
| 184 | |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 185 | endchoice |
| 186 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 187 | config SWAP |
| 188 | bool "Support for paging of anonymous memory (swap)" |
David Howells | 9361401 | 2006-09-30 20:45:40 +0200 | [diff] [blame] | 189 | depends on MMU && BLOCK |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 190 | default y |
| 191 | help |
| 192 | This option allows you to choose whether you want to have support |
Jesper Juhl | 92c3504 | 2006-01-15 02:40:08 +0100 | [diff] [blame] | 193 | for so called swap devices or swap files in your kernel that are |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | used to provide more virtual memory than the actual RAM present |
| 195 | in your computer. If unsure say Y. |
| 196 | |
| 197 | config SYSVIPC |
| 198 | bool "System V IPC" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | ---help--- |
| 200 | Inter Process Communication is a suite of library functions and |
| 201 | system calls which let processes (running programs) synchronize and |
| 202 | exchange information. It is generally considered to be a good thing, |
| 203 | and some programs won't run unless you say Y here. In particular, if |
| 204 | you want to run the DOS emulator dosemu under Linux (read the |
| 205 | DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>), |
| 206 | you'll need to say Y here. |
| 207 | |
| 208 | You can find documentation about IPC with "info ipc" and also in |
| 209 | section 6.4 of the Linux Programmer's Guide, available from |
| 210 | <http://www.tldp.org/guides.html>. |
| 211 | |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 212 | config SYSVIPC_SYSCTL |
| 213 | bool |
| 214 | depends on SYSVIPC |
| 215 | depends on SYSCTL |
| 216 | default y |
| 217 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 218 | config POSIX_MQUEUE |
| 219 | bool "POSIX Message Queues" |
| 220 | depends on NET && EXPERIMENTAL |
| 221 | ---help--- |
| 222 | POSIX variant of message queues is a part of IPC. In POSIX message |
| 223 | queues every message has a priority which decides about succession |
| 224 | of receiving it by a process. If you want to compile and run |
| 225 | programs written e.g. for Solaris with use of its POSIX message |
Robert P. J. Day | b0e3765 | 2007-05-09 07:25:13 +0200 | [diff] [blame] | 226 | queues (functions mq_*) say Y here. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 227 | |
| 228 | POSIX message queues are visible as a filesystem called 'mqueue' |
| 229 | and can be mounted somewhere if you want to do filesystem |
| 230 | operations on message queues. |
| 231 | |
| 232 | If unsure, say Y. |
| 233 | |
Serge E. Hallyn | bdc8e5f | 2009-04-06 19:01:11 -0700 | [diff] [blame] | 234 | config POSIX_MQUEUE_SYSCTL |
| 235 | bool |
| 236 | depends on POSIX_MQUEUE |
| 237 | depends on SYSCTL |
| 238 | default y |
| 239 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | config BSD_PROCESS_ACCT |
| 241 | bool "BSD Process Accounting" |
| 242 | help |
| 243 | If you say Y here, a user level program will be able to instruct the |
| 244 | kernel (via a special system call) to write process accounting |
| 245 | information to a file: whenever a process exits, information about |
| 246 | that process will be appended to the file by the kernel. The |
| 247 | information includes things such as creation time, owning user, |
| 248 | command name, memory usage, controlling terminal etc. (the complete |
| 249 | list is in the struct acct in <file:include/linux/acct.h>). It is |
| 250 | up to the user level program to do useful things with this |
| 251 | information. This is generally a good idea, so say Y. |
| 252 | |
| 253 | config BSD_PROCESS_ACCT_V3 |
| 254 | bool "BSD Process Accounting version 3 file format" |
| 255 | depends on BSD_PROCESS_ACCT |
| 256 | default n |
| 257 | help |
| 258 | If you say Y here, the process accounting information is written |
| 259 | in a new file format that also logs the process IDs of each |
| 260 | process and it's parent. Note that this file format is incompatible |
| 261 | with previous v0/v1/v2 file formats, so you will need updated tools |
| 262 | for processing it. A preliminary version of these tools is available |
S.Çağlar Onur | 37a4c94 | 2008-06-18 11:45:13 +0300 | [diff] [blame] | 263 | at <http://www.gnu.org/software/acct/>. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 265 | config TASKSTATS |
| 266 | bool "Export task/process statistics through netlink (EXPERIMENTAL)" |
| 267 | depends on NET |
| 268 | default n |
| 269 | help |
| 270 | Export selected statistics for tasks/processes through the |
| 271 | generic netlink interface. Unlike BSD process accounting, the |
| 272 | statistics are available during the lifetime of tasks/processes as |
| 273 | responses to commands. Like BSD accounting, they are sent to user |
| 274 | space on task exit. |
| 275 | |
| 276 | Say N if unsure. |
| 277 | |
Shailabh Nagar | ca74e92 | 2006-07-14 00:24:36 -0700 | [diff] [blame] | 278 | config TASK_DELAY_ACCT |
| 279 | bool "Enable per-task delay accounting (EXPERIMENTAL)" |
Shailabh Nagar | 6f44993 | 2006-07-14 00:24:41 -0700 | [diff] [blame] | 280 | depends on TASKSTATS |
Shailabh Nagar | ca74e92 | 2006-07-14 00:24:36 -0700 | [diff] [blame] | 281 | help |
| 282 | Collect information on time spent by a task waiting for system |
| 283 | resources like cpu, synchronous block I/O completion and swapping |
| 284 | in pages. Such statistics can help in setting a task's priorities |
| 285 | relative to other tasks for cpu, io, rss limits etc. |
| 286 | |
| 287 | Say N if unsure. |
| 288 | |
Alexey Dobriyan | 18f705f | 2007-02-10 01:46:44 -0800 | [diff] [blame] | 289 | config TASK_XACCT |
| 290 | bool "Enable extended accounting over taskstats (EXPERIMENTAL)" |
| 291 | depends on TASKSTATS |
| 292 | help |
| 293 | Collect extended task accounting data and send the data |
| 294 | to userland for processing over the taskstats interface. |
| 295 | |
| 296 | Say N if unsure. |
| 297 | |
| 298 | config TASK_IO_ACCOUNTING |
| 299 | bool "Enable per-task storage I/O accounting (EXPERIMENTAL)" |
| 300 | depends on TASK_XACCT |
| 301 | help |
| 302 | Collect information on the number of bytes of storage I/O which this |
| 303 | task has caused. |
| 304 | |
| 305 | Say N if unsure. |
| 306 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | config AUDIT |
| 308 | bool "Auditing support" |
Chris Wright | 804a6a4 | 2005-05-11 10:52:45 +0100 | [diff] [blame] | 309 | depends on NET |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | help |
| 311 | Enable auditing infrastructure that can be used with another |
| 312 | kernel subsystem, such as SELinux (which requires this for |
| 313 | logging of avc messages output). Does not do system-call |
| 314 | auditing without CONFIG_AUDITSYSCALL. |
| 315 | |
| 316 | config AUDITSYSCALL |
| 317 | bool "Enable system-call auditing support" |
Kumar Gala | 022382a | 2009-10-16 07:21:37 +0000 | [diff] [blame] | 318 | depends on AUDIT && (X86 || PPC || S390 || IA64 || UML || SPARC64 || SUPERH) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 319 | default y if SECURITY_SELINUX |
| 320 | help |
| 321 | Enable low-overhead system-call auditing infrastructure that |
| 322 | can be used independently or with another kernel subsystem, |
Eric Paris | 67640b6 | 2009-12-17 20:12:06 -0500 | [diff] [blame] | 323 | such as SELinux. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 324 | |
Eric Paris | 939a67f | 2009-12-17 20:12:06 -0500 | [diff] [blame] | 325 | config AUDIT_WATCH |
| 326 | def_bool y |
| 327 | depends on AUDITSYSCALL |
| 328 | select FSNOTIFY |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 329 | |
Al Viro | 74c3cbe | 2007-07-22 08:04:18 -0400 | [diff] [blame] | 330 | config AUDIT_TREE |
| 331 | def_bool y |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 332 | depends on AUDITSYSCALL |
Eric Paris | 28a3a7e | 2009-12-17 20:12:05 -0500 | [diff] [blame] | 333 | select FSNOTIFY |
Al Viro | 74c3cbe | 2007-07-22 08:04:18 -0400 | [diff] [blame] | 334 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 335 | menu "RCU Subsystem" |
| 336 | |
| 337 | choice |
| 338 | prompt "RCU Implementation" |
Paul E. McKenney | 31c9a24 | 2009-04-02 21:06:25 -0700 | [diff] [blame] | 339 | default TREE_RCU |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 340 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 341 | config TREE_RCU |
| 342 | bool "Tree-based hierarchical RCU" |
Paul E. McKenney | 687d7a9 | 2010-07-21 06:52:40 -0700 | [diff] [blame] | 343 | depends on !PREEMPT && SMP |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 344 | help |
| 345 | This option selects the RCU implementation that is |
| 346 | designed for very large SMP system with hundreds or |
Paul E. McKenney | c17ef45 | 2009-06-23 17:12:47 -0700 | [diff] [blame] | 347 | thousands of CPUs. It also scales down nicely to |
| 348 | smaller systems. |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 349 | |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 350 | config TREE_PREEMPT_RCU |
Paul E. McKenney | a57eb94 | 2010-06-29 16:49:16 -0700 | [diff] [blame] | 351 | bool "Preemptible tree-based hierarchical RCU" |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 352 | depends on PREEMPT |
| 353 | help |
| 354 | This option selects the RCU implementation that is |
| 355 | designed for very large SMP systems with hundreds or |
| 356 | thousands of CPUs, but for which real-time response |
Paul E. McKenney | bbe3eae | 2009-09-13 09:15:08 -0700 | [diff] [blame] | 357 | is also required. It also scales down nicely to |
| 358 | smaller systems. |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 359 | |
Paul E. McKenney | 9b1d82f | 2009-10-25 19:03:50 -0700 | [diff] [blame] | 360 | config TINY_RCU |
| 361 | bool "UP-only small-memory-footprint RCU" |
| 362 | depends on !SMP |
| 363 | help |
| 364 | This option selects the RCU implementation that is |
| 365 | designed for UP systems from which real-time response |
| 366 | is not required. This option greatly reduces the |
| 367 | memory footprint of RCU. |
| 368 | |
Paul E. McKenney | a57eb94 | 2010-06-29 16:49:16 -0700 | [diff] [blame] | 369 | config TINY_PREEMPT_RCU |
| 370 | bool "Preemptible UP-only small-memory-footprint RCU" |
| 371 | depends on !SMP && PREEMPT |
| 372 | help |
| 373 | This option selects the RCU implementation that is designed |
| 374 | for real-time UP systems. This option greatly reduces the |
| 375 | memory footprint of RCU. |
| 376 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 377 | endchoice |
| 378 | |
Paul E. McKenney | a57eb94 | 2010-06-29 16:49:16 -0700 | [diff] [blame] | 379 | config PREEMPT_RCU |
| 380 | def_bool ( TREE_PREEMPT_RCU || TINY_PREEMPT_RCU ) |
| 381 | help |
| 382 | This option enables preemptible-RCU code that is common between |
| 383 | the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations. |
| 384 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 385 | config RCU_TRACE |
| 386 | bool "Enable tracing for RCU" |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 387 | help |
| 388 | This option provides tracing in RCU which presents stats |
| 389 | in debugfs for debugging RCU implementation. |
| 390 | |
| 391 | Say Y here if you want to enable RCU tracing |
| 392 | Say N if you are unsure. |
| 393 | |
| 394 | config RCU_FANOUT |
| 395 | int "Tree-based hierarchical RCU fanout value" |
| 396 | range 2 64 if 64BIT |
| 397 | range 2 32 if !64BIT |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 398 | depends on TREE_RCU || TREE_PREEMPT_RCU |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 399 | default 64 if 64BIT |
| 400 | default 32 if !64BIT |
| 401 | help |
| 402 | This option controls the fanout of hierarchical implementations |
| 403 | of RCU, allowing RCU to work efficiently on machines with |
Paul E. McKenney | 4d87ffa | 2010-08-04 17:31:12 -0700 | [diff] [blame] | 404 | large numbers of CPUs. This value must be at least the fourth |
| 405 | root of NR_CPUS, which allows NR_CPUS to be insanely large. |
| 406 | The default value of RCU_FANOUT should be used for production |
| 407 | systems, but if you are stress-testing the RCU implementation |
| 408 | itself, small RCU_FANOUT values allow you to test large-system |
| 409 | code paths on small(er) systems. |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 410 | |
| 411 | Select a specific number if testing RCU itself. |
| 412 | Take the default if unsure. |
| 413 | |
| 414 | config RCU_FANOUT_EXACT |
| 415 | bool "Disable tree-based hierarchical RCU auto-balancing" |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 416 | depends on TREE_RCU || TREE_PREEMPT_RCU |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 417 | default n |
| 418 | help |
| 419 | This option forces use of the exact RCU_FANOUT value specified, |
| 420 | regardless of imbalances in the hierarchy. This is useful for |
| 421 | testing RCU itself, and might one day be useful on systems with |
| 422 | strong NUMA behavior. |
| 423 | |
| 424 | Without RCU_FANOUT_EXACT, the code will balance the hierarchy. |
| 425 | |
| 426 | Say N if unsure. |
| 427 | |
Paul E. McKenney | 8bd93a2 | 2010-02-22 17:04:59 -0800 | [diff] [blame] | 428 | config RCU_FAST_NO_HZ |
| 429 | bool "Accelerate last non-dyntick-idle CPU's grace periods" |
| 430 | depends on TREE_RCU && NO_HZ && SMP |
| 431 | default n |
| 432 | help |
| 433 | This option causes RCU to attempt to accelerate grace periods |
| 434 | in order to allow the final CPU to enter dynticks-idle state |
| 435 | more quickly. On the other hand, this option increases the |
| 436 | overhead of the dynticks-idle checking, particularly on systems |
| 437 | with large numbers of CPUs. |
| 438 | |
| 439 | Say Y if energy efficiency is critically important, particularly |
| 440 | if you have relatively few CPUs. |
| 441 | |
| 442 | Say N if you are unsure. |
| 443 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 444 | config TREE_RCU_TRACE |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 445 | def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU ) |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 446 | select DEBUG_FS |
| 447 | help |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 448 | This option provides tracing for the TREE_RCU and |
| 449 | TREE_PREEMPT_RCU implementations, permitting Makefile to |
| 450 | trivially select kernel/rcutree_trace.c. |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 451 | |
Paul E. McKenney | 24278d1 | 2010-09-27 17:25:23 -0700 | [diff] [blame] | 452 | config RCU_BOOST |
| 453 | bool "Enable RCU priority boosting" |
| 454 | depends on RT_MUTEXES && TINY_PREEMPT_RCU |
| 455 | default n |
| 456 | help |
| 457 | This option boosts the priority of preempted RCU readers that |
| 458 | block the current preemptible RCU grace period for too long. |
| 459 | This option also prevents heavy loads from blocking RCU |
| 460 | callback invocation for all flavors of RCU. |
| 461 | |
| 462 | Say Y here if you are working with real-time apps or heavy loads |
| 463 | Say N here if you are unsure. |
| 464 | |
| 465 | config RCU_BOOST_PRIO |
| 466 | int "Real-time priority to boost RCU readers to" |
| 467 | range 1 99 |
| 468 | depends on RCU_BOOST |
| 469 | default 1 |
| 470 | help |
| 471 | This option specifies the real-time priority to which preempted |
| 472 | RCU readers are to be boosted. If you are working with CPU-bound |
| 473 | real-time applications, you should specify a priority higher then |
| 474 | the highest-priority CPU-bound application. |
| 475 | |
| 476 | Specify the real-time priority, or take the default if unsure. |
| 477 | |
| 478 | config RCU_BOOST_DELAY |
| 479 | int "Milliseconds to delay boosting after RCU grace-period start" |
| 480 | range 0 3000 |
| 481 | depends on RCU_BOOST |
| 482 | default 500 |
| 483 | help |
| 484 | This option specifies the time to wait after the beginning of |
| 485 | a given grace period before priority-boosting preempted RCU |
| 486 | readers blocking that grace period. Note that any RCU reader |
| 487 | blocking an expedited RCU grace period is boosted immediately. |
| 488 | |
| 489 | Accept the default if unsure. |
| 490 | |
Paul E. McKenney | 46fdb09 | 2010-10-26 02:11:40 -0700 | [diff] [blame^] | 491 | config SRCU_SYNCHRONIZE_DELAY |
| 492 | int "Microseconds to delay before waiting for readers" |
| 493 | range 0 20 |
| 494 | default 10 |
| 495 | help |
| 496 | This option controls how long SRCU delays before entering its |
| 497 | loop waiting on SRCU readers. The purpose of this loop is |
| 498 | to avoid the unconditional context-switch penalty that would |
| 499 | otherwise be incurred if there was an active SRCU reader, |
| 500 | in a manner similar to adaptive locking schemes. This should |
| 501 | be set to be a bit longer than the common-case SRCU read-side |
| 502 | critical-section overhead. |
| 503 | |
| 504 | Accept the default if unsure. |
| 505 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 506 | endmenu # "RCU Subsystem" |
| 507 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 508 | config IKCONFIG |
Ross Biro | f2443ab | 2006-09-30 23:27:25 -0700 | [diff] [blame] | 509 | tristate "Kernel .config support" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 510 | ---help--- |
| 511 | This option enables the complete Linux kernel ".config" file |
| 512 | contents to be saved in the kernel. It provides documentation |
| 513 | of which kernel options are used in a running kernel or in an |
| 514 | on-disk kernel. This information can be extracted from the kernel |
| 515 | image file with the script scripts/extract-ikconfig and used as |
| 516 | input to rebuild the current kernel or to build another kernel. |
| 517 | It can also be extracted from a running kernel by reading |
| 518 | /proc/config.gz if enabled (below). |
| 519 | |
| 520 | config IKCONFIG_PROC |
| 521 | bool "Enable access to .config through /proc/config.gz" |
| 522 | depends on IKCONFIG && PROC_FS |
| 523 | ---help--- |
| 524 | This option enables access to the kernel configuration file |
| 525 | through /proc/config.gz. |
| 526 | |
Alistair John Strachan | 794543a | 2007-05-08 00:31:15 -0700 | [diff] [blame] | 527 | config LOG_BUF_SHIFT |
| 528 | int "Kernel log buffer size (16 => 64KB, 17 => 128KB)" |
| 529 | range 12 21 |
Adrian Bunk | f17a32e | 2008-04-29 00:58:58 -0700 | [diff] [blame] | 530 | default 17 |
Alistair John Strachan | 794543a | 2007-05-08 00:31:15 -0700 | [diff] [blame] | 531 | help |
| 532 | Select kernel log buffer size as a power of 2. |
Adrian Bunk | f17a32e | 2008-04-29 00:58:58 -0700 | [diff] [blame] | 533 | Examples: |
| 534 | 17 => 128 KB |
| 535 | 16 => 64 KB |
| 536 | 15 => 32 KB |
| 537 | 14 => 16 KB |
Alistair John Strachan | 794543a | 2007-05-08 00:31:15 -0700 | [diff] [blame] | 538 | 13 => 8 KB |
| 539 | 12 => 4 KB |
| 540 | |
KAMEZAWA Hiroyuki | 5cdc38f | 2009-01-07 18:07:30 -0800 | [diff] [blame] | 541 | # |
| 542 | # Architectures with an unreliable sched_clock() should select this: |
| 543 | # |
| 544 | config HAVE_UNSTABLE_SCHED_CLOCK |
| 545 | bool |
| 546 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 547 | menuconfig CGROUPS |
| 548 | boolean "Control Group support" |
Kirill A. Shutemov | 0dea116 | 2010-03-10 15:22:20 -0800 | [diff] [blame] | 549 | depends on EVENTFD |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 550 | help |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 551 | This option adds support for grouping sets of processes together, for |
KAMEZAWA Hiroyuki | 5cdc38f | 2009-01-07 18:07:30 -0800 | [diff] [blame] | 552 | use with process control subsystems such as Cpusets, CFS, memory |
| 553 | controls or device isolation. |
| 554 | See |
KAMEZAWA Hiroyuki | 5cdc38f | 2009-01-07 18:07:30 -0800 | [diff] [blame] | 555 | - Documentation/scheduler/sched-design-CFS.txt (CFS) |
Li Zefan | 45ce80f | 2009-01-15 13:50:59 -0800 | [diff] [blame] | 556 | - Documentation/cgroups/ (features for grouping, isolation |
| 557 | and resource control) |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 558 | |
| 559 | Say N if unsure. |
| 560 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 561 | if CGROUPS |
| 562 | |
Paul Menage | 006cb99 | 2007-10-18 23:39:43 -0700 | [diff] [blame] | 563 | config CGROUP_DEBUG |
| 564 | bool "Example debug cgroup subsystem" |
| 565 | depends on CGROUPS |
Paul Menage | 418d7d8 | 2008-04-29 01:00:05 -0700 | [diff] [blame] | 566 | default n |
Paul Menage | 006cb99 | 2007-10-18 23:39:43 -0700 | [diff] [blame] | 567 | help |
| 568 | This option enables a simple cgroup subsystem that |
| 569 | exports useful debugging information about the cgroups |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 570 | framework. |
Paul Menage | 006cb99 | 2007-10-18 23:39:43 -0700 | [diff] [blame] | 571 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 572 | Say N if unsure. |
Paul Menage | 006cb99 | 2007-10-18 23:39:43 -0700 | [diff] [blame] | 573 | |
Serge E. Hallyn | 858d72e | 2007-10-18 23:39:45 -0700 | [diff] [blame] | 574 | config CGROUP_NS |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 575 | bool "Namespace cgroup subsystem" |
| 576 | depends on CGROUPS |
| 577 | help |
| 578 | Provides a simple namespace cgroup subsystem to |
| 579 | provide hierarchical naming of sets of namespaces, |
| 580 | for instance virtual servers and checkpoint/restart |
| 581 | jobs. |
Serge E. Hallyn | 858d72e | 2007-10-18 23:39:45 -0700 | [diff] [blame] | 582 | |
Matt Helsley | dc52ddc | 2008-10-18 20:27:21 -0700 | [diff] [blame] | 583 | config CGROUP_FREEZER |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 584 | bool "Freezer cgroup subsystem" |
| 585 | depends on CGROUPS |
| 586 | help |
| 587 | Provides a way to freeze and unfreeze all tasks in a |
Matt Helsley | dc52ddc | 2008-10-18 20:27:21 -0700 | [diff] [blame] | 588 | cgroup. |
| 589 | |
Serge E. Hallyn | 08ce5f1 | 2008-04-29 01:00:10 -0700 | [diff] [blame] | 590 | config CGROUP_DEVICE |
| 591 | bool "Device controller for cgroups" |
| 592 | depends on CGROUPS && EXPERIMENTAL |
| 593 | help |
| 594 | Provides a cgroup implementing whitelists for devices which |
| 595 | a process in the cgroup can mknod or open. |
| 596 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 597 | config CPUSETS |
| 598 | bool "Cpuset support" |
Paul Menage | db7f47c | 2009-04-02 16:57:55 -0700 | [diff] [blame] | 599 | depends on CGROUPS |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 600 | help |
Randy Dunlap | d9fd8a6 | 2005-07-27 11:45:11 -0700 | [diff] [blame] | 601 | This option will let you create and manage CPUSETs which |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 602 | allow dynamically partitioning a system into sets of CPUs and |
| 603 | Memory Nodes and assigning tasks to run only within those sets. |
| 604 | This is primarily useful on large SMP or NUMA systems. |
| 605 | |
| 606 | Say N if unsure. |
| 607 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 608 | config PROC_PID_CPUSET |
| 609 | bool "Include legacy /proc/<pid>/cpuset file" |
| 610 | depends on CPUSETS |
| 611 | default y |
| 612 | |
Srivatsa Vaddagiri | d842de8 | 2007-12-02 20:04:49 +0100 | [diff] [blame] | 613 | config CGROUP_CPUACCT |
| 614 | bool "Simple CPU accounting cgroup subsystem" |
| 615 | depends on CGROUPS |
| 616 | help |
| 617 | Provides a simple Resource Controller for monitoring the |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 618 | total CPU consumed by the tasks in a cgroup. |
Srivatsa Vaddagiri | d842de8 | 2007-12-02 20:04:49 +0100 | [diff] [blame] | 619 | |
Pavel Emelianov | e552b66 | 2008-02-07 00:13:49 -0800 | [diff] [blame] | 620 | config RESOURCE_COUNTERS |
| 621 | bool "Resource counters" |
| 622 | help |
| 623 | This option enables controller independent resource accounting |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 624 | infrastructure that works with cgroups. |
Pavel Emelianov | e552b66 | 2008-02-07 00:13:49 -0800 | [diff] [blame] | 625 | depends on CGROUPS |
| 626 | |
Balbir Singh | 00f0b82 | 2008-03-04 14:28:39 -0800 | [diff] [blame] | 627 | config CGROUP_MEM_RES_CTLR |
| 628 | bool "Memory Resource Controller for Control Groups" |
| 629 | depends on CGROUPS && RESOURCE_COUNTERS |
Balbir Singh | cf475ad | 2008-04-29 01:00:16 -0700 | [diff] [blame] | 630 | select MM_OWNER |
Balbir Singh | 00f0b82 | 2008-03-04 14:28:39 -0800 | [diff] [blame] | 631 | help |
KAMEZAWA Hiroyuki | 84ad6d7 | 2008-10-29 14:01:06 -0700 | [diff] [blame] | 632 | Provides a memory resource controller that manages both anonymous |
Thadeu Lima de Souza Cascardo | 21acb9c | 2009-02-04 10:12:08 +0100 | [diff] [blame] | 633 | memory and page cache. (See Documentation/cgroups/memory.txt) |
Balbir Singh | 00f0b82 | 2008-03-04 14:28:39 -0800 | [diff] [blame] | 634 | |
| 635 | Note that setting this option increases fixed memory overhead |
KAMEZAWA Hiroyuki | 84ad6d7 | 2008-10-29 14:01:06 -0700 | [diff] [blame] | 636 | associated with each page of memory in the system. By this, |
| 637 | 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory |
| 638 | usage tracking struct at boot. Total amount of this is printed out |
| 639 | at boot. |
Balbir Singh | 00f0b82 | 2008-03-04 14:28:39 -0800 | [diff] [blame] | 640 | |
| 641 | Only enable when you're ok with these trade offs and really |
KAMEZAWA Hiroyuki | 84ad6d7 | 2008-10-29 14:01:06 -0700 | [diff] [blame] | 642 | sure you need the memory resource controller. Even when you enable |
| 643 | this, you can set "cgroup_disable=memory" at your boot option to |
| 644 | disable memory resource controller and you can avoid overheads. |
Li Zefan | c9d5409 | 2009-01-07 18:07:35 -0800 | [diff] [blame] | 645 | (and lose benefits of memory resource controller) |
Balbir Singh | 00f0b82 | 2008-03-04 14:28:39 -0800 | [diff] [blame] | 646 | |
Balbir Singh | cf475ad | 2008-04-29 01:00:16 -0700 | [diff] [blame] | 647 | This config option also selects MM_OWNER config option, which |
| 648 | could in turn add some fork/exit overhead. |
| 649 | |
KAMEZAWA Hiroyuki | c077719 | 2009-01-07 18:07:57 -0800 | [diff] [blame] | 650 | config CGROUP_MEM_RES_CTLR_SWAP |
KAMEZAWA Hiroyuki | 65e0e81 | 2010-08-10 18:02:56 -0700 | [diff] [blame] | 651 | bool "Memory Resource Controller Swap Extension" |
| 652 | depends on CGROUP_MEM_RES_CTLR && SWAP |
KAMEZAWA Hiroyuki | c077719 | 2009-01-07 18:07:57 -0800 | [diff] [blame] | 653 | help |
| 654 | Add swap management feature to memory resource controller. When you |
| 655 | enable this, you can limit mem+swap usage per cgroup. In other words, |
| 656 | when you disable this, memory resource controller has no cares to |
| 657 | usage of swap...a process can exhaust all of the swap. This extension |
| 658 | is useful when you want to avoid exhaustion swap but this itself |
| 659 | adds more overheads and consumes memory for remembering information. |
| 660 | Especially if you use 32bit system or small memory system, please |
| 661 | be careful about enabling this. When memory resource controller |
| 662 | is disabled by boot option, this will be automatically disabled and |
| 663 | there will be no overhead from this. Even when you set this config=y, |
| 664 | if boot option "noswapaccount" is set, swap will not be accounted. |
KAMEZAWA Hiroyuki | 627991a | 2009-04-02 16:57:47 -0700 | [diff] [blame] | 665 | Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page |
| 666 | size is 4096bytes, 512k per 1Gbytes of swap. |
KAMEZAWA Hiroyuki | c077719 | 2009-01-07 18:07:57 -0800 | [diff] [blame] | 667 | |
Dhaval Giani | 7c94143 | 2010-01-20 13:26:18 +0100 | [diff] [blame] | 668 | menuconfig CGROUP_SCHED |
| 669 | bool "Group CPU scheduler" |
| 670 | depends on EXPERIMENTAL && CGROUPS |
| 671 | default n |
| 672 | help |
| 673 | This feature lets CPU scheduler recognize task groups and control CPU |
| 674 | bandwidth allocation to such task groups. It uses cgroups to group |
| 675 | tasks. |
| 676 | |
| 677 | if CGROUP_SCHED |
| 678 | config FAIR_GROUP_SCHED |
| 679 | bool "Group scheduling for SCHED_OTHER" |
| 680 | depends on CGROUP_SCHED |
| 681 | default CGROUP_SCHED |
| 682 | |
| 683 | config RT_GROUP_SCHED |
| 684 | bool "Group scheduling for SCHED_RR/FIFO" |
| 685 | depends on EXPERIMENTAL |
| 686 | depends on CGROUP_SCHED |
| 687 | default n |
| 688 | help |
| 689 | This feature lets you explicitly allocate real CPU bandwidth |
Li Zefan | 32bd7eb | 2010-03-24 13:17:19 +0800 | [diff] [blame] | 690 | to task groups. If enabled, it will also make it impossible to |
Dhaval Giani | 7c94143 | 2010-01-20 13:26:18 +0100 | [diff] [blame] | 691 | schedule realtime tasks for non-root users until you allocate |
| 692 | realtime bandwidth for them. |
| 693 | See Documentation/scheduler/sched-rt-group.txt for more information. |
| 694 | |
| 695 | endif #CGROUP_SCHED |
| 696 | |
Vivek Goyal | afc24d4 | 2010-04-26 19:27:56 +0200 | [diff] [blame] | 697 | config BLK_CGROUP |
| 698 | tristate "Block IO controller" |
| 699 | depends on CGROUPS && BLOCK |
| 700 | default n |
| 701 | ---help--- |
| 702 | Generic block IO controller cgroup interface. This is the common |
| 703 | cgroup interface which should be used by various IO controlling |
| 704 | policies. |
| 705 | |
| 706 | Currently, CFQ IO scheduler uses it to recognize task groups and |
| 707 | control disk bandwidth allocation (proportional time slice allocation) |
| 708 | to such task groups. |
| 709 | |
| 710 | This option only enables generic Block IO controller infrastructure. |
| 711 | One needs to also enable actual IO controlling logic in CFQ for it |
| 712 | to take effect. (CONFIG_CFQ_GROUP_IOSCHED=y). |
| 713 | |
| 714 | See Documentation/cgroups/blkio-controller.txt for more information. |
| 715 | |
| 716 | config DEBUG_BLK_CGROUP |
| 717 | bool "Enable Block IO controller debugging" |
| 718 | depends on BLK_CGROUP |
| 719 | default n |
| 720 | ---help--- |
| 721 | Enable some debugging help. Currently it exports additional stat |
| 722 | files in a cgroup which can be useful for debugging. |
| 723 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 724 | endif # CGROUPS |
KAMEZAWA Hiroyuki | c077719 | 2009-01-07 18:07:57 -0800 | [diff] [blame] | 725 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 726 | config MM_OWNER |
| 727 | bool |
KAMEZAWA Hiroyuki | 5cdc38f | 2009-01-07 18:07:30 -0800 | [diff] [blame] | 728 | |
Kay Sievers | 88a22c9 | 2006-09-14 11:23:28 +0200 | [diff] [blame] | 729 | config SYSFS_DEPRECATED |
Ingo Molnar | d47846c | 2008-03-04 14:54:47 +0100 | [diff] [blame] | 730 | bool |
| 731 | |
| 732 | config SYSFS_DEPRECATED_V2 |
Uwe Kleine-König | 9e9868a | 2009-12-03 19:58:00 +0100 | [diff] [blame] | 733 | bool "enable deprecated sysfs features to support old userspace tools" |
Randy Dunlap | 9148fe8 | 2007-12-31 10:05:34 -0800 | [diff] [blame] | 734 | depends on SYSFS |
Kay Sievers | f6ee649 | 2009-04-16 19:56:37 +0200 | [diff] [blame] | 735 | default n |
Ingo Molnar | d47846c | 2008-03-04 14:54:47 +0100 | [diff] [blame] | 736 | select SYSFS_DEPRECATED |
Kay Sievers | 88a22c9 | 2006-09-14 11:23:28 +0200 | [diff] [blame] | 737 | help |
Kay Sievers | fce3e80 | 2008-11-01 14:03:00 +0100 | [diff] [blame] | 738 | This option switches the layout of sysfs to the deprecated |
Kay Sievers | f6ee649 | 2009-04-16 19:56:37 +0200 | [diff] [blame] | 739 | version. Do not use it on recent distributions. |
Kay Sievers | 88a22c9 | 2006-09-14 11:23:28 +0200 | [diff] [blame] | 740 | |
Kay Sievers | fce3e80 | 2008-11-01 14:03:00 +0100 | [diff] [blame] | 741 | The current sysfs layout features a unified device tree at |
| 742 | /sys/devices/, which is able to express a hierarchy between |
| 743 | class devices. If the deprecated option is set to Y, the |
| 744 | unified device tree is split into a bus device tree at |
| 745 | /sys/devices/ and several individual class device trees at |
| 746 | /sys/class/. The class and bus devices will be connected by |
| 747 | "<subsystem>:<name>" and the "device" links. The "block" |
| 748 | class devices, will not show up in /sys/class/block/. Some |
| 749 | subsystems will suppress the creation of some devices which |
| 750 | depend on the unified device tree. |
Kay Sievers | 88a22c9 | 2006-09-14 11:23:28 +0200 | [diff] [blame] | 751 | |
Kay Sievers | fce3e80 | 2008-11-01 14:03:00 +0100 | [diff] [blame] | 752 | This option is not a pure compatibility option that can |
| 753 | be safely enabled on newer distributions. It will change the |
| 754 | layout of sysfs to the non-extensible deprecated version, |
| 755 | and disable some features, which can not be exported without |
| 756 | confusing older userspace tools. Since 2007/2008 all major |
| 757 | distributions do not enable this option, and ship no tools which |
| 758 | depend on the deprecated layout or this option. |
| 759 | |
| 760 | If you are using a new kernel on an older distribution, or use |
| 761 | older userspace tools, you might need to say Y here. Do not say Y, |
| 762 | if the original kernel, that came with your distribution, has |
| 763 | this option set to N. |
Kay Sievers | 88a22c9 | 2006-09-14 11:23:28 +0200 | [diff] [blame] | 764 | |
Jens Axboe | b86ff98 | 2006-03-23 19:56:55 +0100 | [diff] [blame] | 765 | config RELAY |
| 766 | bool "Kernel->user space relay support (formerly relayfs)" |
| 767 | help |
| 768 | This option enables support for relay interface support in |
| 769 | certain file systems (such as debugfs). |
| 770 | It is designed to provide an efficient mechanism for tools and |
| 771 | facilities to relay large amounts of data from kernel space to |
| 772 | user space. |
| 773 | |
| 774 | If unsure, say N. |
| 775 | |
Pavel Emelyanov | c5289a6 | 2008-02-08 04:18:19 -0800 | [diff] [blame] | 776 | config NAMESPACES |
| 777 | bool "Namespaces support" if EMBEDDED |
| 778 | default !EMBEDDED |
| 779 | help |
| 780 | Provides the way to make tasks work with different objects using |
| 781 | the same id. For example same IPC id may refer to different objects |
| 782 | or same user id or pid may refer to different tasks when used in |
| 783 | different namespaces. |
| 784 | |
Pavel Emelyanov | 58bfdd6d | 2008-02-08 04:18:21 -0800 | [diff] [blame] | 785 | config UTS_NS |
| 786 | bool "UTS namespace" |
| 787 | depends on NAMESPACES |
| 788 | help |
| 789 | In this namespace tasks see different info provided with the |
| 790 | uname() system call |
| 791 | |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 792 | config IPC_NS |
| 793 | bool "IPC namespace" |
Serge E. Hallyn | 614b84c | 2009-04-06 19:01:08 -0700 | [diff] [blame] | 794 | depends on NAMESPACES && (SYSVIPC || POSIX_MQUEUE) |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 795 | help |
| 796 | In this namespace tasks work with IPC ids which correspond to |
Serge E. Hallyn | 614b84c | 2009-04-06 19:01:08 -0700 | [diff] [blame] | 797 | different IPC objects in different namespaces. |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 798 | |
Pavel Emelyanov | aee16ce | 2008-02-08 04:18:23 -0800 | [diff] [blame] | 799 | config USER_NS |
| 800 | bool "User namespace (EXPERIMENTAL)" |
| 801 | depends on NAMESPACES && EXPERIMENTAL |
| 802 | help |
| 803 | This allows containers, i.e. vservers, to use user namespaces |
| 804 | to provide different user info for different servers. |
| 805 | If unsure, say N. |
| 806 | |
Pavel Emelyanov | 74bd59b | 2008-02-08 04:18:24 -0800 | [diff] [blame] | 807 | config PID_NS |
| 808 | bool "PID Namespaces (EXPERIMENTAL)" |
| 809 | default n |
| 810 | depends on NAMESPACES && EXPERIMENTAL |
| 811 | help |
Heikki Orsila | 12d2b8f | 2008-07-06 15:48:02 +0300 | [diff] [blame] | 812 | Support process id namespaces. This allows having multiple |
Matt LaPlante | 692105b | 2009-01-26 11:12:25 +0100 | [diff] [blame] | 813 | processes with the same pid as long as they are in different |
Pavel Emelyanov | 74bd59b | 2008-02-08 04:18:24 -0800 | [diff] [blame] | 814 | pid namespaces. This is a building block of containers. |
| 815 | |
| 816 | Unless you want to work with an experimental feature |
| 817 | say N here. |
| 818 | |
Matt Helsley | d6eb633 | 2009-01-26 12:25:55 -0800 | [diff] [blame] | 819 | config NET_NS |
| 820 | bool "Network namespace" |
| 821 | default n |
| 822 | depends on NAMESPACES && EXPERIMENTAL && NET |
| 823 | help |
| 824 | Allow user space to create what appear to be multiple instances |
| 825 | of the network stack. |
| 826 | |
Dimitri Gorokhovik | f991633 | 2007-03-06 01:42:17 -0800 | [diff] [blame] | 827 | config BLK_DEV_INITRD |
| 828 | bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support" |
| 829 | depends on BROKEN || !FRV |
| 830 | help |
| 831 | The initial RAM filesystem is a ramfs which is loaded by the |
| 832 | boot loader (loadlin or lilo) and that is mounted as root |
| 833 | before the normal boot procedure. It is typically used to |
| 834 | load modules needed to mount the "real" root file system, |
| 835 | etc. See <file:Documentation/initrd.txt> for details. |
| 836 | |
| 837 | If RAM disk support (BLK_DEV_RAM) is also included, this |
| 838 | also enables initial RAM disk (initrd) support and adds |
| 839 | 15 Kbytes (more on some other architectures) to the kernel size. |
| 840 | |
| 841 | If unsure say Y. |
| 842 | |
Jean-Paul Saman | c33df4e | 2007-02-10 01:44:43 -0800 | [diff] [blame] | 843 | if BLK_DEV_INITRD |
| 844 | |
Sam Ravnborg | dbec486 | 2005-08-10 20:44:50 +0200 | [diff] [blame] | 845 | source "usr/Kconfig" |
| 846 | |
Jean-Paul Saman | c33df4e | 2007-02-10 01:44:43 -0800 | [diff] [blame] | 847 | endif |
| 848 | |
Linus Torvalds | c45b4f1 | 2005-12-14 18:52:21 -0800 | [diff] [blame] | 849 | config CC_OPTIMIZE_FOR_SIZE |
Ingo Molnar | 96fffeb | 2008-04-28 01:39:43 +0200 | [diff] [blame] | 850 | bool "Optimize for size" |
Linus Torvalds | c45b4f1 | 2005-12-14 18:52:21 -0800 | [diff] [blame] | 851 | default y |
Linus Torvalds | c45b4f1 | 2005-12-14 18:52:21 -0800 | [diff] [blame] | 852 | help |
| 853 | Enabling this option will pass "-Os" instead of "-O2" to gcc |
| 854 | resulting in a smaller kernel. |
| 855 | |
jkacur | 775a722 | 2008-07-16 00:31:16 +0200 | [diff] [blame] | 856 | If unsure, say Y. |
Linus Torvalds | c45b4f1 | 2005-12-14 18:52:21 -0800 | [diff] [blame] | 857 | |
Randy Dunlap | 0847062 | 2006-09-30 23:28:13 -0700 | [diff] [blame] | 858 | config SYSCTL |
| 859 | bool |
| 860 | |
Randy Dunlap | b943c46 | 2009-03-10 12:55:46 -0700 | [diff] [blame] | 861 | config ANON_INODES |
| 862 | bool |
| 863 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 864 | menuconfig EMBEDDED |
| 865 | bool "Configure standard kernel features (for small systems)" |
| 866 | help |
| 867 | This option allows certain base kernel options and settings |
| 868 | to be disabled or tweaked. This is for specialized |
| 869 | environments which can tolerate a "non-standard" kernel. |
| 870 | Only use this if you really know what you are doing. |
| 871 | |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 872 | config UID16 |
| 873 | bool "Enable 16-bit UID system calls" if EMBEDDED |
David S. Miller | 09337f5 | 2008-04-26 03:17:12 -0700 | [diff] [blame] | 874 | depends on ARM || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && COMPAT) || UML || (X86_64 && IA32_EMULATION) |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 875 | default y |
| 876 | help |
| 877 | This enables the legacy 16-bit UID syscall wrappers. |
| 878 | |
Eric W. Biederman | b89a817 | 2006-09-27 01:51:04 -0700 | [diff] [blame] | 879 | config SYSCTL_SYSCALL |
Randy Dunlap | 0847062 | 2006-09-30 23:28:13 -0700 | [diff] [blame] | 880 | bool "Sysctl syscall support" if EMBEDDED |
Eric W. Biederman | 26a7034 | 2009-11-05 05:26:41 -0800 | [diff] [blame] | 881 | depends on PROC_SYSCTL |
Eric W. Biederman | 13bb7e3 | 2006-11-08 17:44:51 -0800 | [diff] [blame] | 882 | default y |
Eric W. Biederman | b89a817 | 2006-09-27 01:51:04 -0700 | [diff] [blame] | 883 | select SYSCTL |
| 884 | ---help--- |
Eric W. Biederman | 13bb7e3 | 2006-11-08 17:44:51 -0800 | [diff] [blame] | 885 | sys_sysctl uses binary paths that have been found challenging |
| 886 | to properly maintain and use. The interface in /proc/sys |
| 887 | using paths with ascii names is now the primary path to this |
| 888 | information. |
Eric W. Biederman | b89a817 | 2006-09-27 01:51:04 -0700 | [diff] [blame] | 889 | |
Eric W. Biederman | 13bb7e3 | 2006-11-08 17:44:51 -0800 | [diff] [blame] | 890 | Almost nothing using the binary sysctl interface so if you are |
| 891 | trying to save some space it is probably safe to disable this, |
| 892 | making your kernel marginally smaller. |
Eric W. Biederman | b89a817 | 2006-09-27 01:51:04 -0700 | [diff] [blame] | 893 | |
Eric W. Biederman | 13bb7e3 | 2006-11-08 17:44:51 -0800 | [diff] [blame] | 894 | If unsure say Y here. |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 895 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 896 | config KALLSYMS |
Jesper Juhl | 979c6a1 | 2006-12-12 19:25:11 +0100 | [diff] [blame] | 897 | bool "Load all symbols for debugging/ksymoops" if EMBEDDED |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 898 | default y |
| 899 | help |
| 900 | Say Y here to let the kernel print out symbolic crash information and |
| 901 | symbolic stack backtraces. This increases the size of the kernel |
| 902 | somewhat, as all symbols have to be loaded into the kernel image. |
| 903 | |
| 904 | config KALLSYMS_ALL |
| 905 | bool "Include all symbols in kallsyms" |
| 906 | depends on DEBUG_KERNEL && KALLSYMS |
| 907 | help |
| 908 | Normally kallsyms only contains the symbols of functions, for nicer |
| 909 | OOPS messages. Some debuggers can use kallsyms for other |
Jesper Juhl | f9f97bc | 2005-07-20 05:43:05 +0200 | [diff] [blame] | 910 | symbols too: say Y here to include all symbols, if you need them |
| 911 | and you don't care about adding 300k to the size of your kernel. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 912 | |
| 913 | Say N. |
| 914 | |
| 915 | config KALLSYMS_EXTRA_PASS |
| 916 | bool "Do an extra kallsyms pass" |
| 917 | depends on KALLSYMS |
| 918 | help |
| 919 | If kallsyms is not working correctly, the build will fail with |
| 920 | inconsistent kallsyms data. If that occurs, log a bug report and |
| 921 | turn on KALLSYMS_EXTRA_PASS which should result in a stable build. |
| 922 | Always say N here unless you find a bug in kallsyms, which must be |
| 923 | reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while |
| 924 | you wait for kallsyms to be fixed. |
| 925 | |
Matt Mackall | d59745c | 2005-05-01 08:59:02 -0700 | [diff] [blame] | 926 | |
Greg Kroah-Hartman | 712f47c | 2005-11-16 11:27:07 -0800 | [diff] [blame] | 927 | config HOTPLUG |
| 928 | bool "Support for hot-pluggable devices" if EMBEDDED |
| 929 | default y |
| 930 | help |
| 931 | This option is provided for the case where no hotplug or uevent |
| 932 | capabilities is wanted by the kernel. You should only consider |
| 933 | disabling this option for embedded systems that do not use modules, a |
| 934 | dynamic /dev tree, or dynamic device discovery. Just say Y. |
| 935 | |
Matt Mackall | d59745c | 2005-05-01 08:59:02 -0700 | [diff] [blame] | 936 | config PRINTK |
| 937 | default y |
| 938 | bool "Enable support for printk" if EMBEDDED |
| 939 | help |
| 940 | This option enables normal printk support. Removing it |
| 941 | eliminates most of the message strings from the kernel image |
| 942 | and makes the kernel more or less silent. As this makes it |
| 943 | very difficult to diagnose system problems, saying N here is |
| 944 | strongly discouraged. |
| 945 | |
Matt Mackall | c8538a7 | 2005-05-01 08:59:01 -0700 | [diff] [blame] | 946 | config BUG |
| 947 | bool "BUG() support" if EMBEDDED |
| 948 | default y |
| 949 | help |
| 950 | Disabling this option eliminates support for BUG and WARN, reducing |
| 951 | the size of your kernel image and potentially quietly ignoring |
| 952 | numerous fatal conditions. You should only consider disabling this |
| 953 | option for embedded systems with no facilities for reporting errors. |
| 954 | Just say Y. |
| 955 | |
Matt Mackall | 708e9a7 | 2006-01-08 01:05:25 -0800 | [diff] [blame] | 956 | config ELF_CORE |
| 957 | default y |
| 958 | bool "Enable ELF core dumps" if EMBEDDED |
| 959 | help |
| 960 | Enable support for generating core dumps. Disabling saves about 4k. |
| 961 | |
Stas Sergeev | e5e1d3c | 2008-05-07 12:39:56 +0200 | [diff] [blame] | 962 | config PCSPKR_PLATFORM |
| 963 | bool "Enable PC-Speaker support" if EMBEDDED |
| 964 | depends on ALPHA || X86 || MIPS || PPC_PREP || PPC_CHRP || PPC_PSERIES |
| 965 | default y |
| 966 | help |
| 967 | This option allows to disable the internal PC-Speaker |
| 968 | support, saving some memory. |
| 969 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 970 | config BASE_FULL |
| 971 | default y |
| 972 | bool "Enable full-sized data structures for core" if EMBEDDED |
| 973 | help |
| 974 | Disabling this option reduces the size of miscellaneous core |
| 975 | kernel data structures. This saves memory on small machines, |
| 976 | but may reduce performance. |
| 977 | |
| 978 | config FUTEX |
| 979 | bool "Enable futex support" if EMBEDDED |
| 980 | default y |
Ingo Molnar | 23f78d4 | 2006-06-27 02:54:53 -0700 | [diff] [blame] | 981 | select RT_MUTEXES |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 982 | help |
| 983 | Disabling this option will cause the kernel to be built without |
| 984 | support for "fast userspace mutexes". The resulting kernel may not |
| 985 | run glibc-based applications correctly. |
| 986 | |
| 987 | config EPOLL |
| 988 | bool "Enable eventpoll support" if EMBEDDED |
| 989 | default y |
Adrian Bunk | 448e3ce | 2007-07-31 00:39:10 -0700 | [diff] [blame] | 990 | select ANON_INODES |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 991 | help |
| 992 | Disabling this option will cause the kernel to be built without |
| 993 | support for epoll family of system calls. |
| 994 | |
Davide Libenzi | fba2afa | 2007-05-10 22:23:13 -0700 | [diff] [blame] | 995 | config SIGNALFD |
| 996 | bool "Enable signalfd() system call" if EMBEDDED |
Adrian Bunk | 448e3ce | 2007-07-31 00:39:10 -0700 | [diff] [blame] | 997 | select ANON_INODES |
Davide Libenzi | fba2afa | 2007-05-10 22:23:13 -0700 | [diff] [blame] | 998 | default y |
| 999 | help |
| 1000 | Enable the signalfd() system call that allows to receive signals |
| 1001 | on a file descriptor. |
| 1002 | |
| 1003 | If unsure, say Y. |
| 1004 | |
Davide Libenzi | b215e28 | 2007-05-10 22:23:16 -0700 | [diff] [blame] | 1005 | config TIMERFD |
| 1006 | bool "Enable timerfd() system call" if EMBEDDED |
Adrian Bunk | 448e3ce | 2007-07-31 00:39:10 -0700 | [diff] [blame] | 1007 | select ANON_INODES |
Davide Libenzi | b215e28 | 2007-05-10 22:23:16 -0700 | [diff] [blame] | 1008 | default y |
| 1009 | help |
| 1010 | Enable the timerfd() system call that allows to receive timer |
| 1011 | events on a file descriptor. |
| 1012 | |
| 1013 | If unsure, say Y. |
| 1014 | |
Davide Libenzi | e1ad746 | 2007-05-10 22:23:19 -0700 | [diff] [blame] | 1015 | config EVENTFD |
| 1016 | bool "Enable eventfd() system call" if EMBEDDED |
Adrian Bunk | 448e3ce | 2007-07-31 00:39:10 -0700 | [diff] [blame] | 1017 | select ANON_INODES |
Davide Libenzi | e1ad746 | 2007-05-10 22:23:19 -0700 | [diff] [blame] | 1018 | default y |
| 1019 | help |
| 1020 | Enable the eventfd() system call that allows to receive both |
| 1021 | kernel notification (ie. KAIO) or userspace notifications. |
| 1022 | |
| 1023 | If unsure, say Y. |
| 1024 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1025 | config SHMEM |
| 1026 | bool "Use full shmem filesystem" if EMBEDDED |
| 1027 | default y |
| 1028 | depends on MMU |
| 1029 | help |
| 1030 | The shmem is an internal filesystem used to manage shared memory. |
| 1031 | It is backed by swap and manages resource limits. It is also exported |
| 1032 | to userspace as tmpfs if TMPFS is enabled. Disabling this |
| 1033 | option replaces shmem and tmpfs with the much simpler ramfs code, |
| 1034 | which may be appropriate on small systems without swap. |
| 1035 | |
Thomas Petazzoni | ebf3f09 | 2008-10-15 22:05:12 -0700 | [diff] [blame] | 1036 | config AIO |
| 1037 | bool "Enable AIO support" if EMBEDDED |
| 1038 | default y |
| 1039 | help |
| 1040 | This option enables POSIX asynchronous I/O which may by used |
| 1041 | by some high performance threaded applications. Disabling |
| 1042 | this option saves about 7k. |
| 1043 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1044 | config HAVE_PERF_EVENTS |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1045 | bool |
Mike Frysinger | 018df72 | 2009-06-12 13:17:43 -0400 | [diff] [blame] | 1046 | help |
| 1047 | See tools/perf/design.txt for details. |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1048 | |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 1049 | config PERF_USE_VMALLOC |
| 1050 | bool |
| 1051 | help |
| 1052 | See tools/perf/design.txt for details |
| 1053 | |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1054 | menu "Kernel Performance Events And Counters" |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1055 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1056 | config PERF_EVENTS |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1057 | bool "Kernel performance events and counters" |
| 1058 | default y if (PROFILING || PERF_COUNTERS) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1059 | depends on HAVE_PERF_EVENTS |
Ingo Molnar | 4c59e46 | 2008-12-08 19:38:33 +0100 | [diff] [blame] | 1060 | select ANON_INODES |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1061 | help |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1062 | Enable kernel support for various performance events provided |
| 1063 | by software and hardware. |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1064 | |
Thadeu Lima de Souza Cascardo | dd77038 | 2009-10-30 19:32:25 -0200 | [diff] [blame] | 1065 | Software events are supported either built-in or via the |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1066 | use of generic tracepoints. |
| 1067 | |
| 1068 | Most modern CPUs support performance events via performance |
| 1069 | counter registers. These registers count the number of certain |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1070 | types of hw events: such as instructions executed, cachemisses |
| 1071 | suffered, or branches mis-predicted - without slowing down the |
| 1072 | kernel or applications. These registers can also trigger interrupts |
| 1073 | when a threshold number of events have passed - and can thus be |
| 1074 | used to profile the code that runs on that CPU. |
| 1075 | |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1076 | The Linux Performance Event subsystem provides an abstraction of |
Thadeu Lima de Souza Cascardo | dd77038 | 2009-10-30 19:32:25 -0200 | [diff] [blame] | 1077 | these software and hardware event capabilities, available via a |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1078 | system call and used by the "perf" utility in tools/perf/. It |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1079 | provides per task and per CPU counters, and it provides event |
| 1080 | capabilities on top of those. |
| 1081 | |
| 1082 | Say Y if unsure. |
| 1083 | |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1084 | config PERF_COUNTERS |
| 1085 | bool "Kernel performance counters (old config option)" |
| 1086 | depends on HAVE_PERF_EVENTS |
| 1087 | help |
| 1088 | This config has been obsoleted by the PERF_EVENTS |
| 1089 | config option - please see that one for details. |
| 1090 | |
| 1091 | It has no effect on the kernel whether you enable |
| 1092 | it or not, it is a compatibility placeholder. |
| 1093 | |
| 1094 | Say N if unsure. |
| 1095 | |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 1096 | config DEBUG_PERF_USE_VMALLOC |
| 1097 | default n |
| 1098 | bool "Debug: use vmalloc to back perf mmap() buffers" |
| 1099 | depends on PERF_EVENTS && DEBUG_KERNEL |
| 1100 | select PERF_USE_VMALLOC |
| 1101 | help |
| 1102 | Use vmalloc memory to back perf mmap() buffers. |
| 1103 | |
| 1104 | Mostly useful for debugging the vmalloc code on platforms |
| 1105 | that don't require it. |
| 1106 | |
| 1107 | Say N if unsure. |
| 1108 | |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1109 | endmenu |
| 1110 | |
Christoph Lameter | f8891e5 | 2006-06-30 01:55:45 -0700 | [diff] [blame] | 1111 | config VM_EVENT_COUNTERS |
| 1112 | default y |
| 1113 | bool "Enable VM event counters for /proc/vmstat" if EMBEDDED |
| 1114 | help |
Paul Jackson | 2aea4fb | 2006-12-22 01:06:10 -0800 | [diff] [blame] | 1115 | VM event counters are needed for event counts to be shown. |
| 1116 | This option allows the disabling of the VM event counters |
| 1117 | on EMBEDDED systems. /proc/vmstat will only show page counts |
| 1118 | if VM event counters are disabled. |
Christoph Lameter | f8891e5 | 2006-06-30 01:55:45 -0700 | [diff] [blame] | 1119 | |
Thomas Petazzoni | 3d13731 | 2008-08-19 10:28:24 +0200 | [diff] [blame] | 1120 | config PCI_QUIRKS |
| 1121 | default y |
Geert Uytterhoeven | 61cfc7e | 2008-10-22 08:53:25 +0200 | [diff] [blame] | 1122 | bool "Enable PCI quirk workarounds" if EMBEDDED |
| 1123 | depends on PCI |
Thomas Petazzoni | 3d13731 | 2008-08-19 10:28:24 +0200 | [diff] [blame] | 1124 | help |
| 1125 | This enables workarounds for various PCI chipset |
| 1126 | bugs/quirks. Disable this only if your target machine is |
| 1127 | unaffected by PCI quirks. |
| 1128 | |
Christoph Lameter | 41ecc55 | 2007-05-09 02:32:44 -0700 | [diff] [blame] | 1129 | config SLUB_DEBUG |
| 1130 | default y |
| 1131 | bool "Enable SLUB debugging support" if EMBEDDED |
Christoph Lameter | f6acb63 | 2008-04-29 16:16:06 -0700 | [diff] [blame] | 1132 | depends on SLUB && SYSFS |
Christoph Lameter | 41ecc55 | 2007-05-09 02:32:44 -0700 | [diff] [blame] | 1133 | help |
| 1134 | SLUB has extensive debug support features. Disabling these can |
| 1135 | result in significant savings in code size. This also disables |
| 1136 | SLUB sysfs support. /sys/slab will not exist and there will be |
| 1137 | no support for cache validation etc. |
| 1138 | |
Randy Dunlap | b943c46 | 2009-03-10 12:55:46 -0700 | [diff] [blame] | 1139 | config COMPAT_BRK |
| 1140 | bool "Disable heap randomization" |
| 1141 | default y |
| 1142 | help |
| 1143 | Randomizing heap placement makes heap exploits harder, but it |
| 1144 | also breaks ancient binaries (including anything libc5 based). |
| 1145 | This option changes the bootup default to heap randomization |
Matt LaPlante | 692105b | 2009-01-26 11:12:25 +0100 | [diff] [blame] | 1146 | disabled, and can be overridden at runtime by setting |
Randy Dunlap | b943c46 | 2009-03-10 12:55:46 -0700 | [diff] [blame] | 1147 | /proc/sys/kernel/randomize_va_space to 2. |
| 1148 | |
| 1149 | On non-ancient distros (post-2000 ones) N is usually a safe choice. |
| 1150 | |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1151 | choice |
| 1152 | prompt "Choose SLAB allocator" |
Christoph Lameter | a0acd82 | 2007-07-17 04:03:32 -0700 | [diff] [blame] | 1153 | default SLUB |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1154 | help |
| 1155 | This option allows to select a slab allocator. |
| 1156 | |
| 1157 | config SLAB |
| 1158 | bool "SLAB" |
| 1159 | help |
| 1160 | The regular slab allocator that is established and known to work |
Christoph Lameter | 3401388 | 2007-05-09 02:32:47 -0700 | [diff] [blame] | 1161 | well in all environments. It organizes cache hot objects in |
Simon Arlott | 02f5621 | 2008-11-05 22:18:19 +0000 | [diff] [blame] | 1162 | per cpu and per node queues. |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1163 | |
| 1164 | config SLUB |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1165 | bool "SLUB (Unqueued Allocator)" |
| 1166 | help |
| 1167 | SLUB is a slab allocator that minimizes cache line usage |
| 1168 | instead of managing queues of cached objects (SLAB approach). |
| 1169 | Per cpu caching is realized using slabs of objects instead |
| 1170 | of queues of objects. SLUB can use memory efficiently |
Simon Arlott | 02f5621 | 2008-11-05 22:18:19 +0000 | [diff] [blame] | 1171 | and has enhanced diagnostics. SLUB is the default choice for |
| 1172 | a slab allocator. |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1173 | |
| 1174 | config SLOB |
Paul Mundt | 84a01c2 | 2007-07-15 23:38:24 -0700 | [diff] [blame] | 1175 | depends on EMBEDDED |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1176 | bool "SLOB (Simple Allocator)" |
| 1177 | help |
Matt Mackall | 3729145 | 2008-02-04 22:29:38 -0800 | [diff] [blame] | 1178 | SLOB replaces the stock allocator with a drastically simpler |
| 1179 | allocator. SLOB is generally more space efficient but |
| 1180 | does not perform as well on large systems. |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1181 | |
| 1182 | endchoice |
| 1183 | |
Jie Zhang | ea63763 | 2009-12-14 18:00:02 -0800 | [diff] [blame] | 1184 | config MMAP_ALLOW_UNINITIALIZED |
| 1185 | bool "Allow mmapped anonymous memory to be uninitialized" |
| 1186 | depends on EMBEDDED && !MMU |
| 1187 | default n |
| 1188 | help |
| 1189 | Normally, and according to the Linux spec, anonymous memory obtained |
| 1190 | from mmap() has it's contents cleared before it is passed to |
| 1191 | userspace. Enabling this config option allows you to request that |
| 1192 | mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus |
| 1193 | providing a huge performance boost. If this option is not enabled, |
| 1194 | then the flag will be ignored. |
| 1195 | |
| 1196 | This is taken advantage of by uClibc's malloc(), and also by |
| 1197 | ELF-FDPIC binfmt's brk and stack allocator. |
| 1198 | |
| 1199 | Because of the obvious security issues, this option should only be |
| 1200 | enabled on embedded devices where you control what is run in |
| 1201 | userspace. Since that isn't generally a problem on no-MMU systems, |
| 1202 | it is normally safe to say Y here. |
| 1203 | |
| 1204 | See Documentation/nommu-mmap.txt for more information. |
| 1205 | |
Mathieu Desnoyers | 125e564 | 2008-02-02 15:10:36 -0500 | [diff] [blame] | 1206 | config PROFILING |
Robert Richter | b309a29 | 2010-02-26 15:01:23 +0100 | [diff] [blame] | 1207 | bool "Profiling support" |
Mathieu Desnoyers | 125e564 | 2008-02-02 15:10:36 -0500 | [diff] [blame] | 1208 | help |
| 1209 | Say Y here to enable the extended profiling support mechanisms used |
| 1210 | by profilers such as OProfile. |
| 1211 | |
Ingo Molnar | 5f87f11 | 2008-07-23 14:15:22 +0200 | [diff] [blame] | 1212 | # |
| 1213 | # Place an empty function call at each tracepoint site. Can be |
| 1214 | # dynamically changed for a probe function. |
| 1215 | # |
Mathieu Desnoyers | 97e1c18 | 2008-07-18 12:16:16 -0400 | [diff] [blame] | 1216 | config TRACEPOINTS |
Ingo Molnar | 5f87f11 | 2008-07-23 14:15:22 +0200 | [diff] [blame] | 1217 | bool |
Mathieu Desnoyers | 97e1c18 | 2008-07-18 12:16:16 -0400 | [diff] [blame] | 1218 | |
Mathieu Desnoyers | fb32e03 | 2008-02-02 15:10:33 -0500 | [diff] [blame] | 1219 | source "arch/Kconfig" |
| 1220 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1221 | endmenu # General setup |
| 1222 | |
Dmitry Baryshkov | ee7e551 | 2008-06-29 14:18:46 +0400 | [diff] [blame] | 1223 | config HAVE_GENERIC_DMA_COHERENT |
| 1224 | bool |
| 1225 | default n |
| 1226 | |
Linus Torvalds | 158a962 | 2008-01-02 13:04:48 -0800 | [diff] [blame] | 1227 | config SLABINFO |
| 1228 | bool |
| 1229 | depends on PROC_FS |
Christoph Lameter | 0f389ec | 2008-04-14 18:53:02 +0300 | [diff] [blame] | 1230 | depends on SLAB || SLUB_DEBUG |
Linus Torvalds | 158a962 | 2008-01-02 13:04:48 -0800 | [diff] [blame] | 1231 | default y |
| 1232 | |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 1233 | config RT_MUTEXES |
| 1234 | boolean |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 1235 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1236 | config BASE_SMALL |
| 1237 | int |
| 1238 | default 0 if BASE_FULL |
| 1239 | default 1 if !BASE_FULL |
| 1240 | |
Jan Engelhardt | 66da573 | 2007-07-15 23:39:29 -0700 | [diff] [blame] | 1241 | menuconfig MODULES |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1242 | bool "Enable loadable module support" |
| 1243 | help |
| 1244 | Kernel modules are small pieces of compiled code which can |
| 1245 | be inserted in the running kernel, rather than being |
| 1246 | permanently built into the kernel. You use the "modprobe" |
| 1247 | tool to add (and sometimes remove) them. If you say Y here, |
| 1248 | many parts of the kernel can be built as modules (by |
| 1249 | answering M instead of Y where indicated): this is most |
| 1250 | useful for infrequently used options which are not required |
| 1251 | for booting. For more information, see the man pages for |
| 1252 | modprobe, lsmod, modinfo, insmod and rmmod. |
| 1253 | |
| 1254 | If you say Y here, you will need to run "make |
| 1255 | modules_install" to put the modules under /lib/modules/ |
| 1256 | where modprobe can find them (you may need to be root to do |
| 1257 | this). |
| 1258 | |
| 1259 | If unsure, say Y. |
| 1260 | |
Robert P. J. Day | 0b0de14 | 2008-08-04 13:31:32 -0400 | [diff] [blame] | 1261 | if MODULES |
| 1262 | |
Linus Torvalds | 826e450 | 2008-05-04 17:04:16 -0700 | [diff] [blame] | 1263 | config MODULE_FORCE_LOAD |
| 1264 | bool "Forced module loading" |
Linus Torvalds | 826e450 | 2008-05-04 17:04:16 -0700 | [diff] [blame] | 1265 | default n |
| 1266 | help |
Rusty Russell | 91e37a7 | 2008-05-09 16:25:28 +1000 | [diff] [blame] | 1267 | Allow loading of modules without version information (ie. modprobe |
| 1268 | --force). Forced module loading sets the 'F' (forced) taint flag and |
| 1269 | is usually a really bad idea. |
Linus Torvalds | 826e450 | 2008-05-04 17:04:16 -0700 | [diff] [blame] | 1270 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1271 | config MODULE_UNLOAD |
| 1272 | bool "Module unloading" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1273 | help |
| 1274 | Without this option you will not be able to unload any |
| 1275 | modules (note that some modules may not be unloadable |
Denys Vlasenko | f7f5b67 | 2008-07-22 19:24:26 -0500 | [diff] [blame] | 1276 | anyway), which makes your kernel smaller, faster |
| 1277 | and simpler. If unsure, say Y. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1278 | |
| 1279 | config MODULE_FORCE_UNLOAD |
| 1280 | bool "Forced module unloading" |
| 1281 | depends on MODULE_UNLOAD && EXPERIMENTAL |
| 1282 | help |
| 1283 | This option allows you to force a module to unload, even if the |
| 1284 | kernel believes it is unsafe: the kernel will remove the module |
| 1285 | without waiting for anyone to stop using it (using the -f option to |
| 1286 | rmmod). This is mainly for kernel developers and desperate users. |
| 1287 | If unsure, say N. |
| 1288 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1289 | config MODVERSIONS |
Sam Ravnborg | 0d54164 | 2005-12-26 23:04:02 +0100 | [diff] [blame] | 1290 | bool "Module versioning support" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1291 | help |
| 1292 | Usually, you have to use modules compiled with your kernel. |
| 1293 | Saying Y here makes it sometimes possible to use modules |
| 1294 | compiled for different kernels, by adding enough information |
| 1295 | to the modules to (hopefully) spot any changes which would |
| 1296 | make them incompatible with the kernel you are running. If |
| 1297 | unsure, say N. |
| 1298 | |
| 1299 | config MODULE_SRCVERSION_ALL |
| 1300 | bool "Source checksum for all modules" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1301 | help |
| 1302 | Modules which contain a MODULE_VERSION get an extra "srcversion" |
| 1303 | field inserted into their modinfo section, which contains a |
| 1304 | sum of the source files which made it. This helps maintainers |
| 1305 | see exactly which source was used to build a module (since |
| 1306 | others sometimes change the module source without updating |
| 1307 | the version). With this option, such a "srcversion" field |
| 1308 | will be created for all modules. If unsure, say N. |
| 1309 | |
Robert P. J. Day | 0b0de14 | 2008-08-04 13:31:32 -0400 | [diff] [blame] | 1310 | endif # MODULES |
| 1311 | |
Rusty Russell | 98a79d6 | 2008-12-13 21:19:41 +1030 | [diff] [blame] | 1312 | config INIT_ALL_POSSIBLE |
| 1313 | bool |
| 1314 | help |
| 1315 | Back when each arch used to define their own cpu_online_map and |
| 1316 | cpu_possible_map, some of them chose to initialize cpu_possible_map |
| 1317 | with all 1s, and others with all 0s. When they were centralised, |
| 1318 | it was better to provide this option than to break all the archs |
Matt LaPlante | 692105b | 2009-01-26 11:12:25 +0100 | [diff] [blame] | 1319 | and have several arch maintainers pursuing me down dark alleys. |
Rusty Russell | 98a79d6 | 2008-12-13 21:19:41 +1030 | [diff] [blame] | 1320 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1321 | config STOP_MACHINE |
| 1322 | bool |
| 1323 | default y |
| 1324 | depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU |
| 1325 | help |
| 1326 | Need stop_machine() primitive. |
Jens Axboe | 3a65dfe | 2005-11-04 08:43:35 +0100 | [diff] [blame] | 1327 | |
Jens Axboe | 3a65dfe | 2005-11-04 08:43:35 +0100 | [diff] [blame] | 1328 | source "block/Kconfig" |
Avi Kivity | e98c320 | 2007-10-16 23:27:31 -0700 | [diff] [blame] | 1329 | |
| 1330 | config PREEMPT_NOTIFIERS |
| 1331 | bool |
Paul E. McKenney | e260be6 | 2008-01-25 21:08:24 +0100 | [diff] [blame] | 1332 | |
Steffen Klassert | 16295be | 2010-01-06 19:47:10 +1100 | [diff] [blame] | 1333 | config PADATA |
| 1334 | depends on SMP |
| 1335 | bool |
| 1336 | |
Thomas Gleixner | 6beb000 | 2009-11-09 15:21:34 +0000 | [diff] [blame] | 1337 | source "kernel/Kconfig.locks" |