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 | b2670eac | 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 |
Peter Oberparleiter | b99b87f | 2009-06-17 16:28:03 -0700 | [diff] [blame] | 22 | |
Peter Zijlstra | e360adb | 2010-10-14 14:01:34 +0800 | [diff] [blame] | 23 | config IRQ_WORK |
| 24 | bool |
Peter Zijlstra | e360adb | 2010-10-14 14:01:34 +0800 | [diff] [blame] | 25 | |
David Daney | 1dbdc6f | 2012-04-19 14:59:57 -0700 | [diff] [blame] | 26 | config BUILDTIME_EXTABLE_SORT |
| 27 | bool |
| 28 | |
Al Boldi | ff0cfc6 | 2007-07-31 00:39:23 -0700 | [diff] [blame] | 29 | menu "General setup" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | config BROKEN |
| 32 | bool |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | |
| 34 | config BROKEN_ON_SMP |
| 35 | bool |
| 36 | depends on BROKEN || !SMP |
| 37 | default y |
| 38 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | config INIT_ENV_ARG_LIMIT |
| 40 | int |
Adrian Bunk | dd673bc | 2006-06-30 01:55:51 -0700 | [diff] [blame] | 41 | default 32 if !UML |
| 42 | default 128 if UML |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | help |
Randy Dunlap | 34ad92c | 2005-10-30 15:01:46 -0800 | [diff] [blame] | 44 | Maximum of each of the number of arguments and environment |
| 45 | variables passed to init from the kernel command line. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | |
Roland McGrath | 8433646 | 2009-12-21 16:24:06 -0800 | [diff] [blame] | 48 | config CROSS_COMPILE |
| 49 | string "Cross-compiler tool prefix" |
| 50 | help |
| 51 | Same as running 'make CROSS_COMPILE=prefix-' but stored for |
| 52 | default make runs in this kernel build directory. You don't |
| 53 | need to set this unless you want the configured kernel build |
| 54 | directory to select the cross-compiler automatically. |
| 55 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | config LOCALVERSION |
| 57 | string "Local version - append to kernel release" |
| 58 | help |
| 59 | Append an extra string to the end of your kernel version. |
| 60 | This will show up when you type uname, for example. |
| 61 | The string you set here will be appended after the contents of |
| 62 | any files with a filename matching localversion* in your |
| 63 | object and source tree, in that order. Your total string can |
| 64 | be a maximum of 64 characters. |
| 65 | |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 66 | config LOCALVERSION_AUTO |
| 67 | bool "Automatically append version information to the version string" |
| 68 | default y |
| 69 | help |
| 70 | 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] | 71 | release tree by looking for git tags that belong to the current |
| 72 | top of tree revision. |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 73 | |
| 74 | 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] | 75 | 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] | 76 | appended after any matching localversion* files, and after the value |
Robert P. J. Day | 6e5a542 | 2007-05-01 23:08:11 +0200 | [diff] [blame] | 77 | set in CONFIG_LOCALVERSION. |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 78 | |
Robert P. J. Day | 6e5a542 | 2007-05-01 23:08:11 +0200 | [diff] [blame] | 79 | (The actual string used here is the first eight characters produced |
| 80 | by running the command: |
| 81 | |
| 82 | $ git rev-parse --verify HEAD |
| 83 | |
| 84 | which is done within the script "scripts/setlocalversion".) |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 85 | |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 86 | config HAVE_KERNEL_GZIP |
| 87 | bool |
| 88 | |
| 89 | config HAVE_KERNEL_BZIP2 |
| 90 | bool |
| 91 | |
| 92 | config HAVE_KERNEL_LZMA |
| 93 | bool |
| 94 | |
Lasse Collin | 3ebe124 | 2011-01-12 17:01:23 -0800 | [diff] [blame] | 95 | config HAVE_KERNEL_XZ |
| 96 | bool |
| 97 | |
Albin Tonnerre | 7dd65fe | 2010-01-08 14:42:42 -0800 | [diff] [blame] | 98 | config HAVE_KERNEL_LZO |
| 99 | bool |
| 100 | |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 101 | choice |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 102 | prompt "Kernel compression mode" |
| 103 | default KERNEL_GZIP |
Lasse Collin | 3ebe124 | 2011-01-12 17:01:23 -0800 | [diff] [blame] | 104 | depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 105 | help |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 106 | The linux kernel is a kind of self-extracting executable. |
| 107 | Several compression algorithms are available, which differ |
| 108 | in efficiency, compression and decompression speed. |
| 109 | Compression speed is only relevant when building a kernel. |
| 110 | Decompression speed is relevant at each boot. |
| 111 | |
| 112 | If you have any problems with bzip2 or lzma compressed |
| 113 | kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older |
| 114 | version of this functionality (bzip2 only), for 2.4, was |
| 115 | supplied by Christian Ludwig) |
| 116 | |
| 117 | High compression options are mostly useful for users, who |
| 118 | are low on disk space (embedded systems), but for whom ram |
| 119 | size matters less. |
| 120 | |
| 121 | If in doubt, select 'gzip' |
| 122 | |
| 123 | config KERNEL_GZIP |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 124 | bool "Gzip" |
| 125 | depends on HAVE_KERNEL_GZIP |
| 126 | help |
Albin Tonnerre | 7dd65fe | 2010-01-08 14:42:42 -0800 | [diff] [blame] | 127 | The old and tried gzip compression. It provides a good balance |
| 128 | between compression ratio and decompression speed. |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 129 | |
| 130 | config KERNEL_BZIP2 |
| 131 | bool "Bzip2" |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 132 | depends on HAVE_KERNEL_BZIP2 |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 133 | help |
| 134 | Its compression ratio and speed is intermediate. |
Randy Dunlap | 0a4dd35 | 2012-05-31 16:26:46 -0700 | [diff] [blame] | 135 | Decompression speed is slowest among the choices. The kernel |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 136 | size is about 10% smaller with bzip2, in comparison to gzip. |
| 137 | Bzip2 uses a large amount of memory. For modern kernels you |
| 138 | will need at least 8MB RAM or more for booting. |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 139 | |
| 140 | config KERNEL_LZMA |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 141 | bool "LZMA" |
| 142 | depends on HAVE_KERNEL_LZMA |
| 143 | help |
Randy Dunlap | 0a4dd35 | 2012-05-31 16:26:46 -0700 | [diff] [blame] | 144 | This compression algorithm's ratio is best. Decompression speed |
| 145 | is between gzip and bzip2. Compression is slowest. |
| 146 | The kernel size is about 33% smaller with LZMA in comparison to gzip. |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 147 | |
Lasse Collin | 3ebe124 | 2011-01-12 17:01:23 -0800 | [diff] [blame] | 148 | config KERNEL_XZ |
| 149 | bool "XZ" |
| 150 | depends on HAVE_KERNEL_XZ |
| 151 | help |
| 152 | XZ uses the LZMA2 algorithm and instruction set specific |
| 153 | BCJ filters which can improve compression ratio of executable |
| 154 | code. The size of the kernel is about 30% smaller with XZ in |
| 155 | comparison to gzip. On architectures for which there is a BCJ |
| 156 | filter (i386, x86_64, ARM, IA-64, PowerPC, and SPARC), XZ |
| 157 | will create a few percent smaller kernel than plain LZMA. |
| 158 | |
| 159 | The speed is about the same as with LZMA: The decompression |
| 160 | speed of XZ is better than that of bzip2 but worse than gzip |
| 161 | and LZO. Compression is slow. |
| 162 | |
Albin Tonnerre | 7dd65fe | 2010-01-08 14:42:42 -0800 | [diff] [blame] | 163 | config KERNEL_LZO |
| 164 | bool "LZO" |
| 165 | depends on HAVE_KERNEL_LZO |
| 166 | help |
Randy Dunlap | 0a4dd35 | 2012-05-31 16:26:46 -0700 | [diff] [blame] | 167 | Its compression ratio is the poorest among the choices. The kernel |
Stephan Sperber | 681b304 | 2010-07-14 11:23:08 +0200 | [diff] [blame] | 168 | size is about 10% bigger than gzip; however its speed |
Albin Tonnerre | 7dd65fe | 2010-01-08 14:42:42 -0800 | [diff] [blame] | 169 | (both compression and decompression) is the fastest. |
| 170 | |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 171 | endchoice |
| 172 | |
Josh Triplett | bd5dc17 | 2011-06-15 15:08:28 -0700 | [diff] [blame] | 173 | config DEFAULT_HOSTNAME |
| 174 | string "Default hostname" |
| 175 | default "(none)" |
| 176 | help |
| 177 | This option determines the default system hostname before userspace |
| 178 | calls sethostname(2). The kernel traditionally uses "(none)" here, |
| 179 | but you may wish to use a different default here to make a minimal |
| 180 | system more usable with less configuration. |
| 181 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | config SWAP |
| 183 | bool "Support for paging of anonymous memory (swap)" |
David Howells | 9361401 | 2006-09-30 20:45:40 +0200 | [diff] [blame] | 184 | depends on MMU && BLOCK |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | default y |
| 186 | help |
| 187 | This option allows you to choose whether you want to have support |
Jesper Juhl | 92c3504 | 2006-01-15 02:40:08 +0100 | [diff] [blame] | 188 | 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] | 189 | used to provide more virtual memory than the actual RAM present |
| 190 | in your computer. If unsure say Y. |
| 191 | |
| 192 | config SYSVIPC |
| 193 | bool "System V IPC" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | ---help--- |
| 195 | Inter Process Communication is a suite of library functions and |
| 196 | system calls which let processes (running programs) synchronize and |
| 197 | exchange information. It is generally considered to be a good thing, |
| 198 | and some programs won't run unless you say Y here. In particular, if |
| 199 | you want to run the DOS emulator dosemu under Linux (read the |
| 200 | DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>), |
| 201 | you'll need to say Y here. |
| 202 | |
| 203 | You can find documentation about IPC with "info ipc" and also in |
| 204 | section 6.4 of the Linux Programmer's Guide, available from |
| 205 | <http://www.tldp.org/guides.html>. |
| 206 | |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 207 | config SYSVIPC_SYSCTL |
| 208 | bool |
| 209 | depends on SYSVIPC |
| 210 | depends on SYSCTL |
| 211 | default y |
| 212 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | config POSIX_MQUEUE |
| 214 | bool "POSIX Message Queues" |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 215 | depends on NET |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 216 | ---help--- |
| 217 | POSIX variant of message queues is a part of IPC. In POSIX message |
| 218 | queues every message has a priority which decides about succession |
| 219 | of receiving it by a process. If you want to compile and run |
| 220 | 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] | 221 | queues (functions mq_*) say Y here. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 222 | |
| 223 | POSIX message queues are visible as a filesystem called 'mqueue' |
| 224 | and can be mounted somewhere if you want to do filesystem |
| 225 | operations on message queues. |
| 226 | |
| 227 | If unsure, say Y. |
| 228 | |
Serge E. Hallyn | bdc8e5f | 2009-04-06 19:01:11 -0700 | [diff] [blame] | 229 | config POSIX_MQUEUE_SYSCTL |
| 230 | bool |
| 231 | depends on POSIX_MQUEUE |
| 232 | depends on SYSCTL |
| 233 | default y |
| 234 | |
Aneesh Kumar K.V | 990d6c2 | 2011-01-29 18:43:26 +0530 | [diff] [blame] | 235 | config FHANDLE |
| 236 | bool "open by fhandle syscalls" |
| 237 | select EXPORTFS |
| 238 | help |
| 239 | If you say Y here, a user level program will be able to map |
| 240 | file names to handle and then later use the handle for |
| 241 | different file system operations. This is useful in implementing |
| 242 | userspace file servers, which now track files using handles instead |
| 243 | of names. The handle would remain the same even if file names |
| 244 | get renamed. Enables open_by_handle_at(2) and name_to_handle_at(2) |
| 245 | syscalls. |
| 246 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 247 | config AUDIT |
| 248 | bool "Auditing support" |
Chris Wright | 804a6a49 | 2005-05-11 10:52:45 +0100 | [diff] [blame] | 249 | depends on NET |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | help |
| 251 | Enable auditing infrastructure that can be used with another |
| 252 | kernel subsystem, such as SELinux (which requires this for |
| 253 | logging of avc messages output). Does not do system-call |
| 254 | auditing without CONFIG_AUDITSYSCALL. |
| 255 | |
| 256 | config AUDITSYSCALL |
| 257 | bool "Enable system-call auditing support" |
Will Deacon | 8f827a1 | 2012-07-06 15:48:16 +0100 | [diff] [blame] | 258 | depends on AUDIT && (X86 || PPC || S390 || IA64 || UML || SPARC64 || SUPERH || (ARM && AEABI && !OABI_COMPAT)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 259 | default y if SECURITY_SELINUX |
| 260 | help |
| 261 | Enable low-overhead system-call auditing infrastructure that |
| 262 | can be used independently or with another kernel subsystem, |
Eric Paris | 67640b6 | 2009-12-17 20:12:06 -0500 | [diff] [blame] | 263 | such as SELinux. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | |
Eric Paris | 939a67f | 2009-12-17 20:12:06 -0500 | [diff] [blame] | 265 | config AUDIT_WATCH |
| 266 | def_bool y |
| 267 | depends on AUDITSYSCALL |
| 268 | select FSNOTIFY |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 269 | |
Al Viro | 74c3cbe | 2007-07-22 08:04:18 -0400 | [diff] [blame] | 270 | config AUDIT_TREE |
| 271 | def_bool y |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 272 | depends on AUDITSYSCALL |
Eric Paris | 28a3a7e | 2009-12-17 20:12:05 -0500 | [diff] [blame] | 273 | select FSNOTIFY |
Al Viro | 74c3cbe | 2007-07-22 08:04:18 -0400 | [diff] [blame] | 274 | |
Eric Paris | 633b454 | 2012-01-03 14:23:08 -0500 | [diff] [blame] | 275 | config AUDIT_LOGINUID_IMMUTABLE |
| 276 | bool "Make audit loginuid immutable" |
| 277 | depends on AUDIT |
| 278 | help |
Linus Torvalds | f429ee3 | 2012-01-17 16:06:51 -0800 | [diff] [blame] | 279 | The config option toggles if a task setting its loginuid requires |
Eric Paris | 633b454 | 2012-01-03 14:23:08 -0500 | [diff] [blame] | 280 | CAP_SYS_AUDITCONTROL or if that task should require no special permissions |
| 281 | but should instead only allow setting its loginuid if it was never |
| 282 | previously set. On systems which use systemd or a similar central |
| 283 | process to restart login services this should be set to true. On older |
| 284 | systems in which an admin would typically have to directly stop and |
| 285 | start processes this should be set to false. Setting this to true allows |
| 286 | one to drop potentially dangerous capabilites from the login tasks, |
| 287 | but may not be backwards compatible with older init systems. |
| 288 | |
Thomas Gleixner | d9817eb | 2010-09-27 12:45:59 +0000 | [diff] [blame] | 289 | source "kernel/irq/Kconfig" |
Thomas Gleixner | 764e0da | 2012-05-21 23:16:18 +0200 | [diff] [blame] | 290 | source "kernel/time/Kconfig" |
Thomas Gleixner | d9817eb | 2010-09-27 12:45:59 +0000 | [diff] [blame] | 291 | |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 292 | menu "CPU/Task time and stats accounting" |
| 293 | |
Frederic Weisbecker | abf917c | 2012-07-25 07:56:04 +0200 | [diff] [blame] | 294 | config VIRT_CPU_ACCOUNTING |
| 295 | bool |
| 296 | |
Frederic Weisbecker | fdf9c35 | 2012-09-09 14:56:31 +0200 | [diff] [blame] | 297 | choice |
| 298 | prompt "Cputime accounting" |
| 299 | default TICK_CPU_ACCOUNTING if !PPC64 |
Stephen Rothwell | 02fc8d3 | 2013-02-08 14:19:38 +1100 | [diff] [blame] | 300 | default VIRT_CPU_ACCOUNTING_NATIVE if PPC64 |
Frederic Weisbecker | fdf9c35 | 2012-09-09 14:56:31 +0200 | [diff] [blame] | 301 | |
| 302 | # Kind of a stub config for the pure tick based cputime accounting |
| 303 | config TICK_CPU_ACCOUNTING |
| 304 | bool "Simple tick based cputime accounting" |
Frederic Weisbecker | c58b0df | 2013-04-26 15:16:31 +0200 | [diff] [blame] | 305 | depends on !S390 && !NO_HZ_FULL |
Frederic Weisbecker | fdf9c35 | 2012-09-09 14:56:31 +0200 | [diff] [blame] | 306 | help |
| 307 | This is the basic tick based cputime accounting that maintains |
| 308 | statistics about user, system and idle time spent on per jiffies |
| 309 | granularity. |
| 310 | |
| 311 | If unsure, say Y. |
| 312 | |
Frederic Weisbecker | abf917c | 2012-07-25 07:56:04 +0200 | [diff] [blame] | 313 | config VIRT_CPU_ACCOUNTING_NATIVE |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 314 | bool "Deterministic task and CPU time accounting" |
Frederic Weisbecker | c58b0df | 2013-04-26 15:16:31 +0200 | [diff] [blame] | 315 | depends on HAVE_VIRT_CPU_ACCOUNTING && !NO_HZ_FULL |
Frederic Weisbecker | abf917c | 2012-07-25 07:56:04 +0200 | [diff] [blame] | 316 | select VIRT_CPU_ACCOUNTING |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 317 | help |
| 318 | Select this option to enable more accurate task and CPU time |
| 319 | accounting. This is done by reading a CPU counter on each |
| 320 | kernel entry and exit and on transitions within the kernel |
| 321 | between system, softirq and hardirq state, so there is a |
| 322 | small performance impact. In the case of s390 or IBM POWER > 5, |
| 323 | this also enables accounting of stolen time on logically-partitioned |
| 324 | systems. |
| 325 | |
Frederic Weisbecker | abf917c | 2012-07-25 07:56:04 +0200 | [diff] [blame] | 326 | config VIRT_CPU_ACCOUNTING_GEN |
| 327 | bool "Full dynticks CPU time accounting" |
| 328 | depends on HAVE_CONTEXT_TRACKING && 64BIT |
| 329 | select VIRT_CPU_ACCOUNTING |
| 330 | select CONTEXT_TRACKING |
| 331 | help |
| 332 | Select this option to enable task and CPU time accounting on full |
| 333 | dynticks systems. This accounting is implemented by watching every |
| 334 | kernel-user boundaries using the context tracking subsystem. |
| 335 | The accounting is thus performed at the expense of some significant |
| 336 | overhead. |
| 337 | |
| 338 | For now this is only useful if you are working on the full |
| 339 | dynticks subsystem development. |
| 340 | |
| 341 | If unsure, say N. |
| 342 | |
Frederic Weisbecker | fdf9c35 | 2012-09-09 14:56:31 +0200 | [diff] [blame] | 343 | config IRQ_TIME_ACCOUNTING |
| 344 | bool "Fine granularity task level IRQ time accounting" |
Frederic Weisbecker | c58b0df | 2013-04-26 15:16:31 +0200 | [diff] [blame] | 345 | depends on HAVE_IRQ_TIME_ACCOUNTING && !NO_HZ_FULL |
Frederic Weisbecker | fdf9c35 | 2012-09-09 14:56:31 +0200 | [diff] [blame] | 346 | help |
| 347 | Select this option to enable fine granularity task irq time |
| 348 | accounting. This is done by reading a timestamp on each |
| 349 | transitions between softirq and hardirq state, so there can be a |
| 350 | small performance impact. |
| 351 | |
| 352 | If in doubt, say N here. |
| 353 | |
| 354 | endchoice |
| 355 | |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 356 | config BSD_PROCESS_ACCT |
| 357 | bool "BSD Process Accounting" |
| 358 | help |
| 359 | If you say Y here, a user level program will be able to instruct the |
| 360 | kernel (via a special system call) to write process accounting |
| 361 | information to a file: whenever a process exits, information about |
| 362 | that process will be appended to the file by the kernel. The |
| 363 | information includes things such as creation time, owning user, |
| 364 | command name, memory usage, controlling terminal etc. (the complete |
| 365 | list is in the struct acct in <file:include/linux/acct.h>). It is |
| 366 | up to the user level program to do useful things with this |
| 367 | information. This is generally a good idea, so say Y. |
| 368 | |
| 369 | config BSD_PROCESS_ACCT_V3 |
| 370 | bool "BSD Process Accounting version 3 file format" |
| 371 | depends on BSD_PROCESS_ACCT |
| 372 | default n |
| 373 | help |
| 374 | If you say Y here, the process accounting information is written |
| 375 | in a new file format that also logs the process IDs of each |
| 376 | process and it's parent. Note that this file format is incompatible |
| 377 | with previous v0/v1/v2 file formats, so you will need updated tools |
| 378 | for processing it. A preliminary version of these tools is available |
| 379 | at <http://www.gnu.org/software/acct/>. |
| 380 | |
| 381 | config TASKSTATS |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 382 | bool "Export task/process statistics through netlink" |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 383 | depends on NET |
| 384 | default n |
| 385 | help |
| 386 | Export selected statistics for tasks/processes through the |
| 387 | generic netlink interface. Unlike BSD process accounting, the |
| 388 | statistics are available during the lifetime of tasks/processes as |
| 389 | responses to commands. Like BSD accounting, they are sent to user |
| 390 | space on task exit. |
| 391 | |
| 392 | Say N if unsure. |
| 393 | |
| 394 | config TASK_DELAY_ACCT |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 395 | bool "Enable per-task delay accounting" |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 396 | depends on TASKSTATS |
| 397 | help |
| 398 | Collect information on time spent by a task waiting for system |
| 399 | resources like cpu, synchronous block I/O completion and swapping |
| 400 | in pages. Such statistics can help in setting a task's priorities |
| 401 | relative to other tasks for cpu, io, rss limits etc. |
| 402 | |
| 403 | Say N if unsure. |
| 404 | |
| 405 | config TASK_XACCT |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 406 | bool "Enable extended accounting over taskstats" |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 407 | depends on TASKSTATS |
| 408 | help |
| 409 | Collect extended task accounting data and send the data |
| 410 | to userland for processing over the taskstats interface. |
| 411 | |
| 412 | Say N if unsure. |
| 413 | |
| 414 | config TASK_IO_ACCOUNTING |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 415 | bool "Enable per-task storage I/O accounting" |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 416 | depends on TASK_XACCT |
| 417 | help |
| 418 | Collect information on the number of bytes of storage I/O which this |
| 419 | task has caused. |
| 420 | |
| 421 | Say N if unsure. |
| 422 | |
| 423 | endmenu # "CPU/Task time and stats accounting" |
| 424 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 425 | menu "RCU Subsystem" |
| 426 | |
| 427 | choice |
| 428 | prompt "RCU Implementation" |
Paul E. McKenney | 31c9a24 | 2009-04-02 21:06:25 -0700 | [diff] [blame] | 429 | default TREE_RCU |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 430 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 431 | config TREE_RCU |
| 432 | bool "Tree-based hierarchical RCU" |
Paul E. McKenney | 687d7a9 | 2010-07-21 06:52:40 -0700 | [diff] [blame] | 433 | depends on !PREEMPT && SMP |
Steven Rostedt | 016a8d5 | 2013-05-28 17:32:53 -0400 | [diff] [blame] | 434 | select IRQ_WORK |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 435 | help |
| 436 | This option selects the RCU implementation that is |
| 437 | designed for very large SMP system with hundreds or |
Paul E. McKenney | c17ef45 | 2009-06-23 17:12:47 -0700 | [diff] [blame] | 438 | thousands of CPUs. It also scales down nicely to |
| 439 | smaller systems. |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 440 | |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 441 | config TREE_PREEMPT_RCU |
Paul E. McKenney | a57eb94 | 2010-06-29 16:49:16 -0700 | [diff] [blame] | 442 | bool "Preemptible tree-based hierarchical RCU" |
Paul E. McKenney | 9fc52d8 | 2013-01-08 15:48:33 -0800 | [diff] [blame] | 443 | depends on PREEMPT |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 444 | help |
| 445 | This option selects the RCU implementation that is |
| 446 | designed for very large SMP systems with hundreds or |
| 447 | thousands of CPUs, but for which real-time response |
Paul E. McKenney | bbe3eae | 2009-09-13 09:15:08 -0700 | [diff] [blame] | 448 | is also required. It also scales down nicely to |
| 449 | smaller systems. |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 450 | |
Paul E. McKenney | 9fc52d8 | 2013-01-08 15:48:33 -0800 | [diff] [blame] | 451 | Select this option if you are unsure. |
| 452 | |
Paul E. McKenney | 9b1d82f | 2009-10-25 19:03:50 -0700 | [diff] [blame] | 453 | config TINY_RCU |
| 454 | bool "UP-only small-memory-footprint RCU" |
Paul E. McKenney | 8008e12 | 2011-06-08 16:31:33 -0700 | [diff] [blame] | 455 | depends on !PREEMPT && !SMP |
Paul E. McKenney | 9b1d82f | 2009-10-25 19:03:50 -0700 | [diff] [blame] | 456 | help |
| 457 | This option selects the RCU implementation that is |
| 458 | designed for UP systems from which real-time response |
| 459 | is not required. This option greatly reduces the |
| 460 | memory footprint of RCU. |
| 461 | |
Paul E. McKenney | a57eb94 | 2010-06-29 16:49:16 -0700 | [diff] [blame] | 462 | config TINY_PREEMPT_RCU |
| 463 | bool "Preemptible UP-only small-memory-footprint RCU" |
Paul E. McKenney | 8008e12 | 2011-06-08 16:31:33 -0700 | [diff] [blame] | 464 | depends on PREEMPT && !SMP |
Paul E. McKenney | a57eb94 | 2010-06-29 16:49:16 -0700 | [diff] [blame] | 465 | help |
| 466 | This option selects the RCU implementation that is designed |
| 467 | for real-time UP systems. This option greatly reduces the |
| 468 | memory footprint of RCU. |
| 469 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 470 | endchoice |
| 471 | |
Paul E. McKenney | a57eb94 | 2010-06-29 16:49:16 -0700 | [diff] [blame] | 472 | config PREEMPT_RCU |
| 473 | def_bool ( TREE_PREEMPT_RCU || TINY_PREEMPT_RCU ) |
| 474 | help |
| 475 | This option enables preemptible-RCU code that is common between |
| 476 | the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations. |
| 477 | |
Paul E. McKenney | 6bfc09e | 2012-10-19 12:49:17 -0700 | [diff] [blame] | 478 | config RCU_STALL_COMMON |
| 479 | def_bool ( TREE_RCU || TREE_PREEMPT_RCU || RCU_TRACE ) |
| 480 | help |
| 481 | This option enables RCU CPU stall code that is common between |
| 482 | the TINY and TREE variants of RCU. The purpose is to allow |
| 483 | the tiny variants to disable RCU CPU stall warnings, while |
| 484 | making these warnings mandatory for the tree variants. |
| 485 | |
Frederic Weisbecker | 91d1aa43 | 2012-11-27 19:33:25 +0100 | [diff] [blame] | 486 | config CONTEXT_TRACKING |
| 487 | bool |
| 488 | |
Frederic Weisbecker | 2b1d502 | 2012-07-11 20:26:30 +0200 | [diff] [blame] | 489 | config RCU_USER_QS |
| 490 | bool "Consider userspace as in RCU extended quiescent state" |
Frederic Weisbecker | 91d1aa43 | 2012-11-27 19:33:25 +0100 | [diff] [blame] | 491 | depends on HAVE_CONTEXT_TRACKING && SMP |
| 492 | select CONTEXT_TRACKING |
Frederic Weisbecker | 2b1d502 | 2012-07-11 20:26:30 +0200 | [diff] [blame] | 493 | help |
| 494 | This option sets hooks on kernel / userspace boundaries and |
| 495 | puts RCU in extended quiescent state when the CPU runs in |
| 496 | userspace. It means that when a CPU runs in userspace, it is |
| 497 | excluded from the global RCU state machine and thus doesn't |
Paul Gortmaker | af71bef | 2012-10-24 11:07:09 -0700 | [diff] [blame] | 498 | try to keep the timer tick on for RCU. |
Frederic Weisbecker | 2b1d502 | 2012-07-11 20:26:30 +0200 | [diff] [blame] | 499 | |
Frederic Weisbecker | d677124 | 2012-10-11 01:48:28 +0200 | [diff] [blame] | 500 | Unless you want to hack and help the development of the full |
Frederic Weisbecker | 91d1aa43 | 2012-11-27 19:33:25 +0100 | [diff] [blame] | 501 | dynticks mode, you shouldn't enable this option. It also |
Paul Gortmaker | af71bef | 2012-10-24 11:07:09 -0700 | [diff] [blame] | 502 | adds unnecessary overhead. |
Frederic Weisbecker | d677124 | 2012-10-11 01:48:28 +0200 | [diff] [blame] | 503 | |
| 504 | If unsure say N |
| 505 | |
Frederic Weisbecker | 91d1aa43 | 2012-11-27 19:33:25 +0100 | [diff] [blame] | 506 | config CONTEXT_TRACKING_FORCE |
| 507 | bool "Force context tracking" |
| 508 | depends on CONTEXT_TRACKING |
Frederic Weisbecker | 8b43876 | 2013-02-26 15:37:59 +0100 | [diff] [blame] | 509 | default CONTEXT_TRACKING |
Frederic Weisbecker | 1fd2b44 | 2012-07-11 20:26:40 +0200 | [diff] [blame] | 510 | help |
Frederic Weisbecker | 91d1aa43 | 2012-11-27 19:33:25 +0100 | [diff] [blame] | 511 | Probe on user/kernel boundaries by default in order to |
| 512 | test the features that rely on it such as userspace RCU extended |
| 513 | quiescent states. |
| 514 | This test is there for debugging until we have a real user like the |
| 515 | full dynticks mode. |
Frederic Weisbecker | d677124 | 2012-10-11 01:48:28 +0200 | [diff] [blame] | 516 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 517 | config RCU_FANOUT |
| 518 | int "Tree-based hierarchical RCU fanout value" |
| 519 | range 2 64 if 64BIT |
| 520 | range 2 32 if !64BIT |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 521 | depends on TREE_RCU || TREE_PREEMPT_RCU |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 522 | default 64 if 64BIT |
| 523 | default 32 if !64BIT |
| 524 | help |
| 525 | This option controls the fanout of hierarchical implementations |
| 526 | of RCU, allowing RCU to work efficiently on machines with |
Paul E. McKenney | 4d87ffa | 2010-08-04 17:31:12 -0700 | [diff] [blame] | 527 | large numbers of CPUs. This value must be at least the fourth |
| 528 | root of NR_CPUS, which allows NR_CPUS to be insanely large. |
| 529 | The default value of RCU_FANOUT should be used for production |
| 530 | systems, but if you are stress-testing the RCU implementation |
| 531 | itself, small RCU_FANOUT values allow you to test large-system |
| 532 | code paths on small(er) systems. |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 533 | |
| 534 | Select a specific number if testing RCU itself. |
| 535 | Take the default if unsure. |
| 536 | |
Paul E. McKenney | 8932a63 | 2012-04-19 12:20:14 -0700 | [diff] [blame] | 537 | config RCU_FANOUT_LEAF |
| 538 | int "Tree-based hierarchical RCU leaf-level fanout value" |
| 539 | range 2 RCU_FANOUT if 64BIT |
| 540 | range 2 RCU_FANOUT if !64BIT |
| 541 | depends on TREE_RCU || TREE_PREEMPT_RCU |
| 542 | default 16 |
| 543 | help |
| 544 | This option controls the leaf-level fanout of hierarchical |
| 545 | implementations of RCU, and allows trading off cache misses |
| 546 | against lock contention. Systems that synchronize their |
| 547 | scheduling-clock interrupts for energy-efficiency reasons will |
| 548 | want the default because the smaller leaf-level fanout keeps |
| 549 | lock contention levels acceptably low. Very large systems |
| 550 | (hundreds or thousands of CPUs) will instead want to set this |
| 551 | value to the maximum value possible in order to reduce the |
| 552 | number of cache misses incurred during RCU's grace-period |
| 553 | initialization. These systems tend to run CPU-bound, and thus |
| 554 | are not helped by synchronized interrupts, and thus tend to |
| 555 | skew them, which reduces lock contention enough that large |
| 556 | leaf-level fanouts work well. |
| 557 | |
| 558 | Select a specific number if testing RCU itself. |
| 559 | |
| 560 | Select the maximum permissible value for large systems. |
| 561 | |
| 562 | Take the default if unsure. |
| 563 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 564 | config RCU_FANOUT_EXACT |
| 565 | bool "Disable tree-based hierarchical RCU auto-balancing" |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 566 | depends on TREE_RCU || TREE_PREEMPT_RCU |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 567 | default n |
| 568 | help |
| 569 | This option forces use of the exact RCU_FANOUT value specified, |
| 570 | regardless of imbalances in the hierarchy. This is useful for |
| 571 | testing RCU itself, and might one day be useful on systems with |
| 572 | strong NUMA behavior. |
| 573 | |
| 574 | Without RCU_FANOUT_EXACT, the code will balance the hierarchy. |
| 575 | |
| 576 | Say N if unsure. |
| 577 | |
Paul E. McKenney | 8bd93a2 | 2010-02-22 17:04:59 -0800 | [diff] [blame] | 578 | config RCU_FAST_NO_HZ |
| 579 | bool "Accelerate last non-dyntick-idle CPU's grace periods" |
Frederic Weisbecker | 3451d02 | 2011-08-10 23:21:01 +0200 | [diff] [blame] | 580 | depends on NO_HZ_COMMON && SMP |
Paul E. McKenney | 8bd93a2 | 2010-02-22 17:04:59 -0800 | [diff] [blame] | 581 | default n |
| 582 | help |
Paul E. McKenney | c0f4dfd | 2012-12-28 11:30:36 -0800 | [diff] [blame] | 583 | This option permits CPUs to enter dynticks-idle state even if |
| 584 | they have RCU callbacks queued, and prevents RCU from waking |
| 585 | these CPUs up more than roughly once every four jiffies (by |
| 586 | default, you can adjust this using the rcutree.rcu_idle_gp_delay |
| 587 | parameter), thus improving energy efficiency. On the other |
| 588 | hand, this option increases the duration of RCU grace periods, |
| 589 | for example, slowing down synchronize_rcu(). |
Paul E. McKenney | 8bd93a2 | 2010-02-22 17:04:59 -0800 | [diff] [blame] | 590 | |
Paul E. McKenney | c0f4dfd | 2012-12-28 11:30:36 -0800 | [diff] [blame] | 591 | Say Y if energy efficiency is critically important, and you |
| 592 | don't care about increased grace-period durations. |
Paul E. McKenney | 8bd93a2 | 2010-02-22 17:04:59 -0800 | [diff] [blame] | 593 | |
| 594 | Say N if you are unsure. |
| 595 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 596 | config TREE_RCU_TRACE |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 597 | def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU ) |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 598 | select DEBUG_FS |
| 599 | help |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 600 | This option provides tracing for the TREE_RCU and |
| 601 | TREE_PREEMPT_RCU implementations, permitting Makefile to |
| 602 | trivially select kernel/rcutree_trace.c. |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 603 | |
Paul E. McKenney | 24278d1 | 2010-09-27 17:25:23 -0700 | [diff] [blame] | 604 | config RCU_BOOST |
| 605 | bool "Enable RCU priority boosting" |
Paul E. McKenney | 27f4d28 | 2011-02-07 12:47:15 -0800 | [diff] [blame] | 606 | depends on RT_MUTEXES && PREEMPT_RCU |
Paul E. McKenney | 24278d1 | 2010-09-27 17:25:23 -0700 | [diff] [blame] | 607 | default n |
| 608 | help |
| 609 | This option boosts the priority of preempted RCU readers that |
| 610 | block the current preemptible RCU grace period for too long. |
| 611 | This option also prevents heavy loads from blocking RCU |
| 612 | callback invocation for all flavors of RCU. |
| 613 | |
| 614 | Say Y here if you are working with real-time apps or heavy loads |
| 615 | Say N here if you are unsure. |
| 616 | |
| 617 | config RCU_BOOST_PRIO |
| 618 | int "Real-time priority to boost RCU readers to" |
| 619 | range 1 99 |
| 620 | depends on RCU_BOOST |
| 621 | default 1 |
| 622 | help |
Paul E. McKenney | c933664 | 2012-04-18 16:20:18 -0700 | [diff] [blame] | 623 | This option specifies the real-time priority to which long-term |
| 624 | preempted RCU readers are to be boosted. If you are working |
| 625 | with a real-time application that has one or more CPU-bound |
| 626 | threads running at a real-time priority level, you should set |
| 627 | RCU_BOOST_PRIO to a priority higher then the highest-priority |
| 628 | real-time CPU-bound thread. The default RCU_BOOST_PRIO value |
| 629 | of 1 is appropriate in the common case, which is real-time |
| 630 | applications that do not have any CPU-bound threads. |
| 631 | |
| 632 | Some real-time applications might not have a single real-time |
| 633 | thread that saturates a given CPU, but instead might have |
| 634 | multiple real-time threads that, taken together, fully utilize |
| 635 | that CPU. In this case, you should set RCU_BOOST_PRIO to |
| 636 | a priority higher than the lowest-priority thread that is |
| 637 | conspiring to prevent the CPU from running any non-real-time |
| 638 | tasks. For example, if one thread at priority 10 and another |
| 639 | thread at priority 5 are between themselves fully consuming |
| 640 | the CPU time on a given CPU, then RCU_BOOST_PRIO should be |
| 641 | set to priority 6 or higher. |
Paul E. McKenney | 24278d1 | 2010-09-27 17:25:23 -0700 | [diff] [blame] | 642 | |
| 643 | Specify the real-time priority, or take the default if unsure. |
| 644 | |
| 645 | config RCU_BOOST_DELAY |
| 646 | int "Milliseconds to delay boosting after RCU grace-period start" |
| 647 | range 0 3000 |
| 648 | depends on RCU_BOOST |
| 649 | default 500 |
| 650 | help |
| 651 | This option specifies the time to wait after the beginning of |
| 652 | a given grace period before priority-boosting preempted RCU |
| 653 | readers blocking that grace period. Note that any RCU reader |
| 654 | blocking an expedited RCU grace period is boosted immediately. |
| 655 | |
| 656 | Accept the default if unsure. |
| 657 | |
Paul E. McKenney | 3fbfbf7 | 2012-08-19 21:35:53 -0700 | [diff] [blame] | 658 | config RCU_NOCB_CPU |
Paul E. McKenney | 9a5739d | 2013-03-28 20:48:36 -0700 | [diff] [blame] | 659 | bool "Offload RCU callback processing from boot-selected CPUs" |
Paul E. McKenney | 3fbfbf7 | 2012-08-19 21:35:53 -0700 | [diff] [blame] | 660 | depends on TREE_RCU || TREE_PREEMPT_RCU |
| 661 | default n |
| 662 | help |
| 663 | Use this option to reduce OS jitter for aggressive HPC or |
| 664 | real-time workloads. It can also be used to offload RCU |
| 665 | callback invocation to energy-efficient CPUs in battery-powered |
| 666 | asymmetric multiprocessors. |
| 667 | |
| 668 | This option offloads callback invocation from the set of |
| 669 | CPUs specified at boot time by the rcu_nocbs parameter. |
Paul E. McKenney | a488985 | 2012-12-03 08:16:28 -0800 | [diff] [blame] | 670 | For each such CPU, a kthread ("rcuox/N") will be created to |
| 671 | invoke callbacks, where the "N" is the CPU being offloaded, |
| 672 | and where the "x" is "b" for RCU-bh, "p" for RCU-preempt, and |
| 673 | "s" for RCU-sched. Nothing prevents this kthread from running |
| 674 | on the specified CPUs, but (1) the kthreads may be preempted |
| 675 | between each callback, and (2) affinity or cgroups can be used |
| 676 | to force the kthreads to run on whatever set of CPUs is desired. |
Paul E. McKenney | 3fbfbf7 | 2012-08-19 21:35:53 -0700 | [diff] [blame] | 677 | |
Paul E. McKenney | 34ed6246 | 2013-01-07 13:37:42 -0800 | [diff] [blame] | 678 | Say Y here if you want to help to debug reduced OS jitter. |
Paul E. McKenney | 3fbfbf7 | 2012-08-19 21:35:53 -0700 | [diff] [blame] | 679 | Say N here if you are unsure. |
| 680 | |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 681 | choice |
| 682 | prompt "Build-forced no-CBs CPUs" |
| 683 | default RCU_NOCB_CPU_NONE |
| 684 | help |
Paul E. McKenney | 676c3dc | 2013-04-30 14:49:42 -0700 | [diff] [blame^] | 685 | This option allows no-CBs CPUs (whose RCU callbacks are invoked |
| 686 | from kthreads rather than from softirq context) to be specified |
| 687 | at build time. Additional no-CBs CPUs may be specified by |
| 688 | the rcu_nocbs= boot parameter. |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 689 | |
| 690 | config RCU_NOCB_CPU_NONE |
| 691 | bool "No build_forced no-CBs CPUs" |
Frederic Weisbecker | 73c3082 | 2013-05-03 01:28:12 +0200 | [diff] [blame] | 692 | depends on RCU_NOCB_CPU && !NO_HZ_FULL |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 693 | help |
| 694 | This option does not force any of the CPUs to be no-CBs CPUs. |
| 695 | Only CPUs designated by the rcu_nocbs= boot parameter will be |
Paul E. McKenney | 676c3dc | 2013-04-30 14:49:42 -0700 | [diff] [blame^] | 696 | no-CBs CPUs, whose RCU callbacks will be invoked by per-CPU |
| 697 | kthreads whose names begin with "rcuo". All other CPUs will |
| 698 | invoke their own RCU callbacks in softirq context. |
| 699 | |
| 700 | Select this option if you want to choose no-CBs CPUs at |
| 701 | boot time, for example, to allow testing of different no-CBs |
| 702 | configurations without having to rebuild the kernel each time. |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 703 | |
| 704 | config RCU_NOCB_CPU_ZERO |
| 705 | bool "CPU 0 is a build_forced no-CBs CPU" |
Frederic Weisbecker | 73c3082 | 2013-05-03 01:28:12 +0200 | [diff] [blame] | 706 | depends on RCU_NOCB_CPU && !NO_HZ_FULL |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 707 | help |
Paul E. McKenney | 676c3dc | 2013-04-30 14:49:42 -0700 | [diff] [blame^] | 708 | This option forces CPU 0 to be a no-CBs CPU, so that its RCU |
| 709 | callbacks are invoked by a per-CPU kthread whose name begins |
| 710 | with "rcuo". Additional CPUs may be designated as no-CBs |
| 711 | CPUs using the rcu_nocbs= boot parameter will be no-CBs CPUs. |
| 712 | All other CPUs will invoke their own RCU callbacks in softirq |
| 713 | context. |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 714 | |
| 715 | Select this if CPU 0 needs to be a no-CBs CPU for real-time |
Paul E. McKenney | 676c3dc | 2013-04-30 14:49:42 -0700 | [diff] [blame^] | 716 | or energy-efficiency reasons, but the real reason it exists |
| 717 | is to ensure that randconfig testing covers mixed systems. |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 718 | |
| 719 | config RCU_NOCB_CPU_ALL |
| 720 | bool "All CPUs are build_forced no-CBs CPUs" |
| 721 | depends on RCU_NOCB_CPU |
| 722 | help |
| 723 | This option forces all CPUs to be no-CBs CPUs. The rcu_nocbs= |
Paul E. McKenney | 676c3dc | 2013-04-30 14:49:42 -0700 | [diff] [blame^] | 724 | boot parameter will be ignored. All CPUs' RCU callbacks will |
| 725 | be executed in the context of per-CPU rcuo kthreads created for |
| 726 | this purpose. Assuming that the kthreads whose names start with |
| 727 | "rcuo" are bound to "housekeeping" CPUs, this reduces OS jitter |
| 728 | on the remaining CPUs, but might decrease memory locality during |
| 729 | RCU-callback invocation, thus potentially degrading throughput. |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 730 | |
| 731 | Select this if all CPUs need to be no-CBs CPUs for real-time |
| 732 | or energy-efficiency reasons. |
| 733 | |
| 734 | endchoice |
| 735 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 736 | endmenu # "RCU Subsystem" |
| 737 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 738 | config IKCONFIG |
Ross Biro | f2443ab | 2006-09-30 23:27:25 -0700 | [diff] [blame] | 739 | tristate "Kernel .config support" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 740 | ---help--- |
| 741 | This option enables the complete Linux kernel ".config" file |
| 742 | contents to be saved in the kernel. It provides documentation |
| 743 | of which kernel options are used in a running kernel or in an |
| 744 | on-disk kernel. This information can be extracted from the kernel |
| 745 | image file with the script scripts/extract-ikconfig and used as |
| 746 | input to rebuild the current kernel or to build another kernel. |
| 747 | It can also be extracted from a running kernel by reading |
| 748 | /proc/config.gz if enabled (below). |
| 749 | |
| 750 | config IKCONFIG_PROC |
| 751 | bool "Enable access to .config through /proc/config.gz" |
| 752 | depends on IKCONFIG && PROC_FS |
| 753 | ---help--- |
| 754 | This option enables access to the kernel configuration file |
| 755 | through /proc/config.gz. |
| 756 | |
Alistair John Strachan | 794543a | 2007-05-08 00:31:15 -0700 | [diff] [blame] | 757 | config LOG_BUF_SHIFT |
| 758 | int "Kernel log buffer size (16 => 64KB, 17 => 128KB)" |
| 759 | range 12 21 |
Adrian Bunk | f17a32e | 2008-04-29 00:58:58 -0700 | [diff] [blame] | 760 | default 17 |
Alistair John Strachan | 794543a | 2007-05-08 00:31:15 -0700 | [diff] [blame] | 761 | help |
| 762 | Select kernel log buffer size as a power of 2. |
Adrian Bunk | f17a32e | 2008-04-29 00:58:58 -0700 | [diff] [blame] | 763 | Examples: |
| 764 | 17 => 128 KB |
| 765 | 16 => 64 KB |
| 766 | 15 => 32 KB |
| 767 | 14 => 16 KB |
Alistair John Strachan | 794543a | 2007-05-08 00:31:15 -0700 | [diff] [blame] | 768 | 13 => 8 KB |
| 769 | 12 => 4 KB |
| 770 | |
KAMEZAWA Hiroyuki | 5cdc38f | 2009-01-07 18:07:30 -0800 | [diff] [blame] | 771 | # |
| 772 | # Architectures with an unreliable sched_clock() should select this: |
| 773 | # |
| 774 | config HAVE_UNSTABLE_SCHED_CLOCK |
| 775 | bool |
| 776 | |
Andrea Arcangeli | be3a728 | 2012-10-04 01:50:47 +0200 | [diff] [blame] | 777 | # |
| 778 | # For architectures that want to enable the support for NUMA-affine scheduler |
| 779 | # balancing logic: |
| 780 | # |
| 781 | config ARCH_SUPPORTS_NUMA_BALANCING |
| 782 | bool |
| 783 | |
| 784 | # For architectures that (ab)use NUMA to represent different memory regions |
| 785 | # all cpu-local but of different latencies, such as SuperH. |
| 786 | # |
| 787 | config ARCH_WANT_NUMA_VARIABLE_LOCALITY |
| 788 | bool |
| 789 | |
| 790 | # |
| 791 | # For architectures that are willing to define _PAGE_NUMA as _PAGE_PROTNONE |
| 792 | config ARCH_WANTS_PROT_NUMA_PROT_NONE |
| 793 | bool |
| 794 | |
| 795 | config ARCH_USES_NUMA_PROT_NONE |
| 796 | bool |
| 797 | default y |
| 798 | depends on ARCH_WANTS_PROT_NUMA_PROT_NONE |
| 799 | depends on NUMA_BALANCING |
| 800 | |
Mel Gorman | 1a687c2 | 2012-11-22 11:16:36 +0000 | [diff] [blame] | 801 | config NUMA_BALANCING_DEFAULT_ENABLED |
| 802 | bool "Automatically enable NUMA aware memory/task placement" |
| 803 | default y |
| 804 | depends on NUMA_BALANCING |
| 805 | help |
| 806 | If set, autonumic NUMA balancing will be enabled if running on a NUMA |
| 807 | machine. |
| 808 | |
Andrea Arcangeli | be3a728 | 2012-10-04 01:50:47 +0200 | [diff] [blame] | 809 | config NUMA_BALANCING |
| 810 | bool "Memory placement aware NUMA scheduler" |
Andrea Arcangeli | be3a728 | 2012-10-04 01:50:47 +0200 | [diff] [blame] | 811 | depends on ARCH_SUPPORTS_NUMA_BALANCING |
| 812 | depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY |
| 813 | depends on SMP && NUMA && MIGRATION |
| 814 | help |
| 815 | This option adds support for automatic NUMA aware memory/task placement. |
| 816 | The mechanism is quite primitive and is based on migrating memory when |
| 817 | it is references to the node the task is running on. |
| 818 | |
| 819 | This system will be inactive on UMA systems. |
| 820 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 821 | menuconfig CGROUPS |
| 822 | boolean "Control Group support" |
Kirill A. Shutemov | 0dea116 | 2010-03-10 15:22:20 -0800 | [diff] [blame] | 823 | depends on EVENTFD |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 824 | help |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 825 | This option adds support for grouping sets of processes together, for |
KAMEZAWA Hiroyuki | 5cdc38f | 2009-01-07 18:07:30 -0800 | [diff] [blame] | 826 | use with process control subsystems such as Cpusets, CFS, memory |
| 827 | controls or device isolation. |
| 828 | See |
KAMEZAWA Hiroyuki | 5cdc38f | 2009-01-07 18:07:30 -0800 | [diff] [blame] | 829 | - Documentation/scheduler/sched-design-CFS.txt (CFS) |
Li Zefan | 45ce80f | 2009-01-15 13:50:59 -0800 | [diff] [blame] | 830 | - Documentation/cgroups/ (features for grouping, isolation |
| 831 | and resource control) |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 832 | |
| 833 | Say N if unsure. |
| 834 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 835 | if CGROUPS |
| 836 | |
Paul Menage | 006cb99 | 2007-10-18 23:39:43 -0700 | [diff] [blame] | 837 | config CGROUP_DEBUG |
| 838 | bool "Example debug cgroup subsystem" |
Paul Menage | 418d7d8 | 2008-04-29 01:00:05 -0700 | [diff] [blame] | 839 | default n |
Paul Menage | 006cb99 | 2007-10-18 23:39:43 -0700 | [diff] [blame] | 840 | help |
| 841 | This option enables a simple cgroup subsystem that |
| 842 | exports useful debugging information about the cgroups |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 843 | framework. |
Paul Menage | 006cb99 | 2007-10-18 23:39:43 -0700 | [diff] [blame] | 844 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 845 | Say N if unsure. |
Paul Menage | 006cb99 | 2007-10-18 23:39:43 -0700 | [diff] [blame] | 846 | |
Matt Helsley | dc52ddc | 2008-10-18 20:27:21 -0700 | [diff] [blame] | 847 | config CGROUP_FREEZER |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 848 | bool "Freezer cgroup subsystem" |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 849 | help |
| 850 | Provides a way to freeze and unfreeze all tasks in a |
Matt Helsley | dc52ddc | 2008-10-18 20:27:21 -0700 | [diff] [blame] | 851 | cgroup. |
| 852 | |
Serge E. Hallyn | 08ce5f1 | 2008-04-29 01:00:10 -0700 | [diff] [blame] | 853 | config CGROUP_DEVICE |
| 854 | bool "Device controller for cgroups" |
Serge E. Hallyn | 08ce5f1 | 2008-04-29 01:00:10 -0700 | [diff] [blame] | 855 | help |
| 856 | Provides a cgroup implementing whitelists for devices which |
| 857 | a process in the cgroup can mknod or open. |
| 858 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 859 | config CPUSETS |
| 860 | bool "Cpuset support" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 861 | help |
Randy Dunlap | d9fd8a6 | 2005-07-27 11:45:11 -0700 | [diff] [blame] | 862 | This option will let you create and manage CPUSETs which |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 863 | allow dynamically partitioning a system into sets of CPUs and |
| 864 | Memory Nodes and assigning tasks to run only within those sets. |
| 865 | This is primarily useful on large SMP or NUMA systems. |
| 866 | |
| 867 | Say N if unsure. |
| 868 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 869 | config PROC_PID_CPUSET |
| 870 | bool "Include legacy /proc/<pid>/cpuset file" |
| 871 | depends on CPUSETS |
| 872 | default y |
| 873 | |
Srivatsa Vaddagiri | d842de8 | 2007-12-02 20:04:49 +0100 | [diff] [blame] | 874 | config CGROUP_CPUACCT |
| 875 | bool "Simple CPU accounting cgroup subsystem" |
Srivatsa Vaddagiri | d842de8 | 2007-12-02 20:04:49 +0100 | [diff] [blame] | 876 | help |
| 877 | Provides a simple Resource Controller for monitoring the |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 878 | total CPU consumed by the tasks in a cgroup. |
Srivatsa Vaddagiri | d842de8 | 2007-12-02 20:04:49 +0100 | [diff] [blame] | 879 | |
Pavel Emelianov | e552b66 | 2008-02-07 00:13:49 -0800 | [diff] [blame] | 880 | config RESOURCE_COUNTERS |
| 881 | bool "Resource counters" |
| 882 | help |
| 883 | This option enables controller independent resource accounting |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 884 | infrastructure that works with cgroups. |
Pavel Emelianov | e552b66 | 2008-02-07 00:13:49 -0800 | [diff] [blame] | 885 | |
Andrew Morton | c255a45 | 2012-07-31 16:43:02 -0700 | [diff] [blame] | 886 | config MEMCG |
Balbir Singh | 00f0b82 | 2008-03-04 14:28:39 -0800 | [diff] [blame] | 887 | bool "Memory Resource Controller for Control Groups" |
Daniel Lezcano | 79ae9c2 | 2010-10-27 15:34:39 -0700 | [diff] [blame] | 888 | depends on RESOURCE_COUNTERS |
Balbir Singh | cf475ad | 2008-04-29 01:00:16 -0700 | [diff] [blame] | 889 | select MM_OWNER |
Balbir Singh | 00f0b82 | 2008-03-04 14:28:39 -0800 | [diff] [blame] | 890 | help |
KAMEZAWA Hiroyuki | 84ad6d7 | 2008-10-29 14:01:06 -0700 | [diff] [blame] | 891 | Provides a memory resource controller that manages both anonymous |
Thadeu Lima de Souza Cascardo | 21acb9c | 2009-02-04 10:12:08 +0100 | [diff] [blame] | 892 | memory and page cache. (See Documentation/cgroups/memory.txt) |
Balbir Singh | 00f0b82 | 2008-03-04 14:28:39 -0800 | [diff] [blame] | 893 | |
| 894 | Note that setting this option increases fixed memory overhead |
KAMEZAWA Hiroyuki | 84ad6d7 | 2008-10-29 14:01:06 -0700 | [diff] [blame] | 895 | associated with each page of memory in the system. By this, |
| 896 | 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory |
| 897 | usage tracking struct at boot. Total amount of this is printed out |
| 898 | at boot. |
Balbir Singh | 00f0b82 | 2008-03-04 14:28:39 -0800 | [diff] [blame] | 899 | |
| 900 | Only enable when you're ok with these trade offs and really |
KAMEZAWA Hiroyuki | 84ad6d7 | 2008-10-29 14:01:06 -0700 | [diff] [blame] | 901 | sure you need the memory resource controller. Even when you enable |
| 902 | this, you can set "cgroup_disable=memory" at your boot option to |
| 903 | disable memory resource controller and you can avoid overheads. |
Li Zefan | c9d5409 | 2009-01-07 18:07:35 -0800 | [diff] [blame] | 904 | (and lose benefits of memory resource controller) |
Balbir Singh | 00f0b82 | 2008-03-04 14:28:39 -0800 | [diff] [blame] | 905 | |
Balbir Singh | cf475ad | 2008-04-29 01:00:16 -0700 | [diff] [blame] | 906 | This config option also selects MM_OWNER config option, which |
| 907 | could in turn add some fork/exit overhead. |
| 908 | |
Andrew Morton | c255a45 | 2012-07-31 16:43:02 -0700 | [diff] [blame] | 909 | config MEMCG_SWAP |
KAMEZAWA Hiroyuki | 65e0e81 | 2010-08-10 18:02:56 -0700 | [diff] [blame] | 910 | bool "Memory Resource Controller Swap Extension" |
Andrew Morton | c255a45 | 2012-07-31 16:43:02 -0700 | [diff] [blame] | 911 | depends on MEMCG && SWAP |
KAMEZAWA Hiroyuki | c077719 | 2009-01-07 18:07:57 -0800 | [diff] [blame] | 912 | help |
| 913 | Add swap management feature to memory resource controller. When you |
| 914 | enable this, you can limit mem+swap usage per cgroup. In other words, |
| 915 | when you disable this, memory resource controller has no cares to |
| 916 | usage of swap...a process can exhaust all of the swap. This extension |
| 917 | is useful when you want to avoid exhaustion swap but this itself |
| 918 | adds more overheads and consumes memory for remembering information. |
| 919 | Especially if you use 32bit system or small memory system, please |
| 920 | be careful about enabling this. When memory resource controller |
| 921 | is disabled by boot option, this will be automatically disabled and |
| 922 | there will be no overhead from this. Even when you set this config=y, |
WANG Cong | 00a66d2 | 2011-07-25 17:12:12 -0700 | [diff] [blame] | 923 | if boot option "swapaccount=0" is set, swap will not be accounted. |
KAMEZAWA Hiroyuki | 627991a | 2009-04-02 16:57:47 -0700 | [diff] [blame] | 924 | Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page |
| 925 | size is 4096bytes, 512k per 1Gbytes of swap. |
Andrew Morton | c255a45 | 2012-07-31 16:43:02 -0700 | [diff] [blame] | 926 | config MEMCG_SWAP_ENABLED |
Michal Hocko | a42c390 | 2010-11-24 12:57:08 -0800 | [diff] [blame] | 927 | bool "Memory Resource Controller Swap Extension enabled by default" |
Andrew Morton | c255a45 | 2012-07-31 16:43:02 -0700 | [diff] [blame] | 928 | depends on MEMCG_SWAP |
Michal Hocko | a42c390 | 2010-11-24 12:57:08 -0800 | [diff] [blame] | 929 | default y |
| 930 | help |
| 931 | Memory Resource Controller Swap Extension comes with its price in |
| 932 | a bigger memory consumption. General purpose distribution kernels |
Jim Cromie | 43d547f | 2010-12-17 14:32:36 -0700 | [diff] [blame] | 933 | which want to enable the feature but keep it disabled by default |
Michal Hocko | a42c390 | 2010-11-24 12:57:08 -0800 | [diff] [blame] | 934 | and let the user enable it by swapaccount boot command line |
| 935 | parameter should have this option unselected. |
| 936 | For those who want to have the feature enabled by default should |
| 937 | select this option (if, for some reason, they need to disable it |
WANG Cong | 00a66d2 | 2011-07-25 17:12:12 -0700 | [diff] [blame] | 938 | then swapaccount=0 does the trick). |
Andrew Morton | c255a45 | 2012-07-31 16:43:02 -0700 | [diff] [blame] | 939 | config MEMCG_KMEM |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 940 | bool "Memory Resource Controller Kernel Memory accounting" |
| 941 | depends on MEMCG |
Glauber Costa | 510fc4e | 2012-12-18 14:21:47 -0800 | [diff] [blame] | 942 | depends on SLUB || SLAB |
Glauber Costa | e5671df | 2011-12-11 21:47:01 +0000 | [diff] [blame] | 943 | help |
| 944 | The Kernel Memory extension for Memory Resource Controller can limit |
| 945 | the amount of memory used by kernel objects in the system. Those are |
| 946 | fundamentally different from the entities handled by the standard |
| 947 | Memory Controller, which are page-based, and can be swapped. Users of |
| 948 | the kmem extension can use it to guarantee that no group of processes |
| 949 | will ever exhaust kernel resources alone. |
KAMEZAWA Hiroyuki | c077719 | 2009-01-07 18:07:57 -0800 | [diff] [blame] | 950 | |
Aneesh Kumar K.V | 2bc64a2 | 2012-07-31 16:42:12 -0700 | [diff] [blame] | 951 | config CGROUP_HUGETLB |
| 952 | bool "HugeTLB Resource Controller for Control Groups" |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 953 | depends on RESOURCE_COUNTERS && HUGETLB_PAGE |
Aneesh Kumar K.V | 2bc64a2 | 2012-07-31 16:42:12 -0700 | [diff] [blame] | 954 | default n |
| 955 | help |
| 956 | Provides a cgroup Resource Controller for HugeTLB pages. |
| 957 | When you enable this, you can put a per cgroup limit on HugeTLB usage. |
| 958 | The limit is enforced during page fault. Since HugeTLB doesn't |
| 959 | support page reclaim, enforcing the limit at page fault time implies |
| 960 | that, the application will get SIGBUS signal if it tries to access |
| 961 | HugeTLB pages beyond its limit. This requires the application to know |
| 962 | beforehand how much HugeTLB pages it would require for its use. The |
| 963 | control group is tracked in the third page lru pointer. This means |
| 964 | that we cannot use the controller with huge page less than 3 pages. |
| 965 | |
Stephane Eranian | e5d1367 | 2011-02-14 11:20:01 +0200 | [diff] [blame] | 966 | config CGROUP_PERF |
| 967 | bool "Enable perf_event per-cpu per-container group (cgroup) monitoring" |
| 968 | depends on PERF_EVENTS && CGROUPS |
| 969 | help |
| 970 | This option extends the per-cpu mode to restrict monitoring to |
Li Zefan | 2d0f252 | 2011-03-03 14:26:20 +0800 | [diff] [blame] | 971 | threads which belong to the cgroup specified and run on the |
Stephane Eranian | e5d1367 | 2011-02-14 11:20:01 +0200 | [diff] [blame] | 972 | designated cpu. |
| 973 | |
| 974 | Say N if unsure. |
| 975 | |
Dhaval Giani | 7c94143 | 2010-01-20 13:26:18 +0100 | [diff] [blame] | 976 | menuconfig CGROUP_SCHED |
| 977 | bool "Group CPU scheduler" |
Dhaval Giani | 7c94143 | 2010-01-20 13:26:18 +0100 | [diff] [blame] | 978 | default n |
| 979 | help |
| 980 | This feature lets CPU scheduler recognize task groups and control CPU |
| 981 | bandwidth allocation to such task groups. It uses cgroups to group |
| 982 | tasks. |
| 983 | |
| 984 | if CGROUP_SCHED |
| 985 | config FAIR_GROUP_SCHED |
| 986 | bool "Group scheduling for SCHED_OTHER" |
| 987 | depends on CGROUP_SCHED |
| 988 | default CGROUP_SCHED |
| 989 | |
Paul Turner | ab84d31 | 2011-07-21 09:43:28 -0700 | [diff] [blame] | 990 | config CFS_BANDWIDTH |
| 991 | bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED" |
Paul Turner | ab84d31 | 2011-07-21 09:43:28 -0700 | [diff] [blame] | 992 | depends on FAIR_GROUP_SCHED |
| 993 | default n |
| 994 | help |
| 995 | This option allows users to define CPU bandwidth rates (limits) for |
| 996 | tasks running within the fair group scheduler. Groups with no limit |
| 997 | set are considered to be unconstrained and will run with no |
| 998 | restriction. |
| 999 | See tip/Documentation/scheduler/sched-bwc.txt for more information. |
| 1000 | |
Dhaval Giani | 7c94143 | 2010-01-20 13:26:18 +0100 | [diff] [blame] | 1001 | config RT_GROUP_SCHED |
| 1002 | bool "Group scheduling for SCHED_RR/FIFO" |
Dhaval Giani | 7c94143 | 2010-01-20 13:26:18 +0100 | [diff] [blame] | 1003 | depends on CGROUP_SCHED |
| 1004 | default n |
| 1005 | help |
| 1006 | This feature lets you explicitly allocate real CPU bandwidth |
Li Zefan | 32bd7eb | 2010-03-24 13:17:19 +0800 | [diff] [blame] | 1007 | to task groups. If enabled, it will also make it impossible to |
Dhaval Giani | 7c94143 | 2010-01-20 13:26:18 +0100 | [diff] [blame] | 1008 | schedule realtime tasks for non-root users until you allocate |
| 1009 | realtime bandwidth for them. |
| 1010 | See Documentation/scheduler/sched-rt-group.txt for more information. |
| 1011 | |
| 1012 | endif #CGROUP_SCHED |
| 1013 | |
Vivek Goyal | afc24d4 | 2010-04-26 19:27:56 +0200 | [diff] [blame] | 1014 | config BLK_CGROUP |
Tejun Heo | 32e380a | 2012-03-05 13:14:54 -0800 | [diff] [blame] | 1015 | bool "Block IO controller" |
Daniel Lezcano | 79ae9c2 | 2010-10-27 15:34:39 -0700 | [diff] [blame] | 1016 | depends on BLOCK |
Vivek Goyal | afc24d4 | 2010-04-26 19:27:56 +0200 | [diff] [blame] | 1017 | default n |
| 1018 | ---help--- |
| 1019 | Generic block IO controller cgroup interface. This is the common |
| 1020 | cgroup interface which should be used by various IO controlling |
| 1021 | policies. |
| 1022 | |
| 1023 | Currently, CFQ IO scheduler uses it to recognize task groups and |
| 1024 | control disk bandwidth allocation (proportional time slice allocation) |
Vivek Goyal | e43473b | 2010-09-15 17:06:35 -0400 | [diff] [blame] | 1025 | to such task groups. It is also used by bio throttling logic in |
| 1026 | block layer to implement upper limit in IO rates on a device. |
Vivek Goyal | afc24d4 | 2010-04-26 19:27:56 +0200 | [diff] [blame] | 1027 | |
| 1028 | This option only enables generic Block IO controller infrastructure. |
Vivek Goyal | e43473b | 2010-09-15 17:06:35 -0400 | [diff] [blame] | 1029 | One needs to also enable actual IO controlling logic/policy. For |
Michael Witten | 79e2e75 | 2011-01-16 21:43:10 +0000 | [diff] [blame] | 1030 | enabling proportional weight division of disk bandwidth in CFQ, set |
| 1031 | CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set |
Michael Witten | c5e0591 | 2011-01-17 00:08:41 +0000 | [diff] [blame] | 1032 | CONFIG_BLK_DEV_THROTTLING=y. |
Vivek Goyal | afc24d4 | 2010-04-26 19:27:56 +0200 | [diff] [blame] | 1033 | |
| 1034 | See Documentation/cgroups/blkio-controller.txt for more information. |
| 1035 | |
| 1036 | config DEBUG_BLK_CGROUP |
| 1037 | bool "Enable Block IO controller debugging" |
| 1038 | depends on BLK_CGROUP |
| 1039 | default n |
| 1040 | ---help--- |
| 1041 | Enable some debugging help. Currently it exports additional stat |
| 1042 | files in a cgroup which can be useful for debugging. |
| 1043 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 1044 | endif # CGROUPS |
KAMEZAWA Hiroyuki | c077719 | 2009-01-07 18:07:57 -0800 | [diff] [blame] | 1045 | |
Cyrill Gorcunov | 067bce1 | 2012-01-12 17:20:49 -0800 | [diff] [blame] | 1046 | config CHECKPOINT_RESTORE |
| 1047 | bool "Checkpoint/restore support" if EXPERT |
| 1048 | default n |
| 1049 | help |
| 1050 | Enables additional kernel features in a sake of checkpoint/restore. |
| 1051 | In particular it adds auxiliary prctl codes to setup process text, |
| 1052 | data and heap segment sizes, and a few additional /proc filesystem |
| 1053 | entries. |
| 1054 | |
| 1055 | If unsure, say N here. |
| 1056 | |
Daniel Lezcano | 8dd2a82 | 2010-10-27 15:34:38 -0700 | [diff] [blame] | 1057 | menuconfig NAMESPACES |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1058 | bool "Namespaces support" if EXPERT |
| 1059 | default !EXPERT |
Pavel Emelyanov | c5289a6 | 2008-02-08 04:18:19 -0800 | [diff] [blame] | 1060 | help |
| 1061 | Provides the way to make tasks work with different objects using |
| 1062 | the same id. For example same IPC id may refer to different objects |
| 1063 | or same user id or pid may refer to different tasks when used in |
| 1064 | different namespaces. |
| 1065 | |
Daniel Lezcano | 8dd2a82 | 2010-10-27 15:34:38 -0700 | [diff] [blame] | 1066 | if NAMESPACES |
| 1067 | |
Pavel Emelyanov | 58bfdd6d | 2008-02-08 04:18:21 -0800 | [diff] [blame] | 1068 | config UTS_NS |
| 1069 | bool "UTS namespace" |
Daniel Lezcano | 17a6d44 | 2010-10-27 15:34:37 -0700 | [diff] [blame] | 1070 | default y |
Pavel Emelyanov | 58bfdd6d | 2008-02-08 04:18:21 -0800 | [diff] [blame] | 1071 | help |
| 1072 | In this namespace tasks see different info provided with the |
| 1073 | uname() system call |
| 1074 | |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 1075 | config IPC_NS |
| 1076 | bool "IPC namespace" |
Daniel Lezcano | 8dd2a82 | 2010-10-27 15:34:38 -0700 | [diff] [blame] | 1077 | depends on (SYSVIPC || POSIX_MQUEUE) |
Daniel Lezcano | 17a6d44 | 2010-10-27 15:34:37 -0700 | [diff] [blame] | 1078 | default y |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 1079 | help |
| 1080 | In this namespace tasks work with IPC ids which correspond to |
Serge E. Hallyn | 614b84c | 2009-04-06 19:01:08 -0700 | [diff] [blame] | 1081 | different IPC objects in different namespaces. |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 1082 | |
Pavel Emelyanov | aee16ce | 2008-02-08 04:18:23 -0800 | [diff] [blame] | 1083 | config USER_NS |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 1084 | bool "User namespace" |
Eric W. Biederman | e1c972b | 2012-04-21 04:09:01 -0700 | [diff] [blame] | 1085 | depends on UIDGID_CONVERTED |
Eric W. Biederman | 5673a94 | 2011-11-17 10:23:55 -0800 | [diff] [blame] | 1086 | select UIDGID_STRICT_TYPE_CHECKS |
Eric W. Biederman | e1c972b | 2012-04-21 04:09:01 -0700 | [diff] [blame] | 1087 | |
Eric W. Biederman | 5673a94 | 2011-11-17 10:23:55 -0800 | [diff] [blame] | 1088 | default n |
Pavel Emelyanov | aee16ce | 2008-02-08 04:18:23 -0800 | [diff] [blame] | 1089 | help |
| 1090 | This allows containers, i.e. vservers, to use user namespaces |
| 1091 | to provide different user info for different servers. |
Eric W. Biederman | e11f0ae | 2013-01-25 16:48:31 -0800 | [diff] [blame] | 1092 | |
| 1093 | When user namespaces are enabled in the kernel it is |
| 1094 | recommended that the MEMCG and MEMCG_KMEM options also be |
| 1095 | enabled and that user-space use the memory control groups to |
| 1096 | limit the amount of memory a memory unprivileged users can |
| 1097 | use. |
| 1098 | |
Pavel Emelyanov | aee16ce | 2008-02-08 04:18:23 -0800 | [diff] [blame] | 1099 | If unsure, say N. |
| 1100 | |
Pavel Emelyanov | 74bd59b | 2008-02-08 04:18:24 -0800 | [diff] [blame] | 1101 | config PID_NS |
Daniel Lezcano | 9bd38c2 | 2010-10-27 15:34:37 -0700 | [diff] [blame] | 1102 | bool "PID Namespaces" |
Daniel Lezcano | 17a6d44 | 2010-10-27 15:34:37 -0700 | [diff] [blame] | 1103 | default y |
Pavel Emelyanov | 74bd59b | 2008-02-08 04:18:24 -0800 | [diff] [blame] | 1104 | help |
Heikki Orsila | 12d2b8f | 2008-07-06 15:48:02 +0300 | [diff] [blame] | 1105 | Support process id namespaces. This allows having multiple |
Matt LaPlante | 692105b | 2009-01-26 11:12:25 +0100 | [diff] [blame] | 1106 | processes with the same pid as long as they are in different |
Pavel Emelyanov | 74bd59b | 2008-02-08 04:18:24 -0800 | [diff] [blame] | 1107 | pid namespaces. This is a building block of containers. |
| 1108 | |
Matt Helsley | d6eb633 | 2009-01-26 12:25:55 -0800 | [diff] [blame] | 1109 | config NET_NS |
| 1110 | bool "Network namespace" |
Daniel Lezcano | 8dd2a82 | 2010-10-27 15:34:38 -0700 | [diff] [blame] | 1111 | depends on NET |
Daniel Lezcano | 17a6d44 | 2010-10-27 15:34:37 -0700 | [diff] [blame] | 1112 | default y |
Matt Helsley | d6eb633 | 2009-01-26 12:25:55 -0800 | [diff] [blame] | 1113 | help |
| 1114 | Allow user space to create what appear to be multiple instances |
| 1115 | of the network stack. |
| 1116 | |
Daniel Lezcano | 8dd2a82 | 2010-10-27 15:34:38 -0700 | [diff] [blame] | 1117 | endif # NAMESPACES |
| 1118 | |
Eric W. Biederman | e1c972b | 2012-04-21 04:09:01 -0700 | [diff] [blame] | 1119 | config UIDGID_CONVERTED |
| 1120 | # True if all of the selected software conmponents are known |
| 1121 | # to have uid_t and gid_t converted to kuid_t and kgid_t |
| 1122 | # where appropriate and are otherwise safe to use with |
| 1123 | # the user namespace. |
| 1124 | bool |
| 1125 | default y |
| 1126 | |
Eric W. Biederman | e1c972b | 2012-04-21 04:09:01 -0700 | [diff] [blame] | 1127 | # Filesystems |
Eric W. Biederman | e1c972b | 2012-04-21 04:09:01 -0700 | [diff] [blame] | 1128 | depends on XFS_FS = n |
| 1129 | |
Eric W. Biederman | 5673a94 | 2011-11-17 10:23:55 -0800 | [diff] [blame] | 1130 | config UIDGID_STRICT_TYPE_CHECKS |
| 1131 | bool "Require conversions between uid/gids and their internal representation" |
Eric W. Biederman | e1c972b | 2012-04-21 04:09:01 -0700 | [diff] [blame] | 1132 | depends on UIDGID_CONVERTED |
Eric W. Biederman | 5673a94 | 2011-11-17 10:23:55 -0800 | [diff] [blame] | 1133 | default n |
| 1134 | help |
| 1135 | While the nececessary conversions are being added to all subsystems this option allows |
| 1136 | the code to continue to build for unconverted subsystems. |
| 1137 | |
| 1138 | Say Y here if you want the strict type checking enabled |
| 1139 | |
Mike Galbraith | 5091faa | 2010-11-30 14:18:03 +0100 | [diff] [blame] | 1140 | config SCHED_AUTOGROUP |
| 1141 | bool "Automatic process group scheduling" |
| 1142 | select EVENTFD |
| 1143 | select CGROUPS |
| 1144 | select CGROUP_SCHED |
| 1145 | select FAIR_GROUP_SCHED |
| 1146 | help |
| 1147 | This option optimizes the scheduler for common desktop workloads by |
| 1148 | automatically creating and populating task groups. This separation |
| 1149 | of workloads isolates aggressive CPU burners (like build jobs) from |
| 1150 | desktop applications. Task group autogeneration is currently based |
| 1151 | upon task session. |
| 1152 | |
Daniel Lezcano | 7af37be | 2010-10-27 15:34:41 -0700 | [diff] [blame] | 1153 | config MM_OWNER |
| 1154 | bool |
| 1155 | |
| 1156 | config SYSFS_DEPRECATED |
Ferenc Wagner | 5d6a4ea | 2011-01-10 19:04:22 +0100 | [diff] [blame] | 1157 | bool "Enable deprecated sysfs features to support old userspace tools" |
Daniel Lezcano | 7af37be | 2010-10-27 15:34:41 -0700 | [diff] [blame] | 1158 | depends on SYSFS |
| 1159 | default n |
| 1160 | help |
| 1161 | This option adds code that switches the layout of the "block" class |
| 1162 | devices, to not show up in /sys/class/block/, but only in |
| 1163 | /sys/block/. |
| 1164 | |
| 1165 | This switch is only active when the sysfs.deprecated=1 boot option is |
| 1166 | passed or the SYSFS_DEPRECATED_V2 option is set. |
| 1167 | |
| 1168 | This option allows new kernels to run on old distributions and tools, |
| 1169 | which might get confused by /sys/class/block/. Since 2007/2008 all |
| 1170 | major distributions and tools handle this just fine. |
| 1171 | |
| 1172 | Recent distributions and userspace tools after 2009/2010 depend on |
| 1173 | the existence of /sys/class/block/, and will not work with this |
| 1174 | option enabled. |
| 1175 | |
| 1176 | Only if you are using a new kernel on an old distribution, you might |
| 1177 | need to say Y here. |
| 1178 | |
| 1179 | config SYSFS_DEPRECATED_V2 |
Ferenc Wagner | 5d6a4ea | 2011-01-10 19:04:22 +0100 | [diff] [blame] | 1180 | bool "Enable deprecated sysfs features by default" |
Daniel Lezcano | 7af37be | 2010-10-27 15:34:41 -0700 | [diff] [blame] | 1181 | default n |
| 1182 | depends on SYSFS |
| 1183 | depends on SYSFS_DEPRECATED |
| 1184 | help |
| 1185 | Enable deprecated sysfs by default. |
| 1186 | |
| 1187 | See the CONFIG_SYSFS_DEPRECATED option for more details about this |
| 1188 | option. |
| 1189 | |
| 1190 | Only if you are using a new kernel on an old distribution, you might |
| 1191 | need to say Y here. Even then, odds are you would not need it |
| 1192 | enabled, you can always pass the boot option if absolutely necessary. |
| 1193 | |
| 1194 | config RELAY |
| 1195 | bool "Kernel->user space relay support (formerly relayfs)" |
| 1196 | help |
| 1197 | This option enables support for relay interface support in |
| 1198 | certain file systems (such as debugfs). |
| 1199 | It is designed to provide an efficient mechanism for tools and |
| 1200 | facilities to relay large amounts of data from kernel space to |
| 1201 | user space. |
| 1202 | |
| 1203 | If unsure, say N. |
| 1204 | |
Dimitri Gorokhovik | f991633 | 2007-03-06 01:42:17 -0800 | [diff] [blame] | 1205 | config BLK_DEV_INITRD |
| 1206 | bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support" |
| 1207 | depends on BROKEN || !FRV |
| 1208 | help |
| 1209 | The initial RAM filesystem is a ramfs which is loaded by the |
| 1210 | boot loader (loadlin or lilo) and that is mounted as root |
| 1211 | before the normal boot procedure. It is typically used to |
| 1212 | load modules needed to mount the "real" root file system, |
| 1213 | etc. See <file:Documentation/initrd.txt> for details. |
| 1214 | |
| 1215 | If RAM disk support (BLK_DEV_RAM) is also included, this |
| 1216 | also enables initial RAM disk (initrd) support and adds |
| 1217 | 15 Kbytes (more on some other architectures) to the kernel size. |
| 1218 | |
| 1219 | If unsure say Y. |
| 1220 | |
Jean-Paul Saman | c33df4e | 2007-02-10 01:44:43 -0800 | [diff] [blame] | 1221 | if BLK_DEV_INITRD |
| 1222 | |
Sam Ravnborg | dbec486 | 2005-08-10 20:44:50 +0200 | [diff] [blame] | 1223 | source "usr/Kconfig" |
| 1224 | |
Jean-Paul Saman | c33df4e | 2007-02-10 01:44:43 -0800 | [diff] [blame] | 1225 | endif |
| 1226 | |
Linus Torvalds | c45b4f1 | 2005-12-14 18:52:21 -0800 | [diff] [blame] | 1227 | config CC_OPTIMIZE_FOR_SIZE |
Ingo Molnar | 96fffeb | 2008-04-28 01:39:43 +0200 | [diff] [blame] | 1228 | bool "Optimize for size" |
Linus Torvalds | c45b4f1 | 2005-12-14 18:52:21 -0800 | [diff] [blame] | 1229 | help |
| 1230 | Enabling this option will pass "-Os" instead of "-O2" to gcc |
| 1231 | resulting in a smaller kernel. |
| 1232 | |
Kirill Smelkov | 3a55fb0 | 2012-11-02 15:41:01 +0400 | [diff] [blame] | 1233 | If unsure, say N. |
Linus Torvalds | c45b4f1 | 2005-12-14 18:52:21 -0800 | [diff] [blame] | 1234 | |
Randy Dunlap | 0847062 | 2006-09-30 23:28:13 -0700 | [diff] [blame] | 1235 | config SYSCTL |
| 1236 | bool |
| 1237 | |
Randy Dunlap | b943c46 | 2009-03-10 12:55:46 -0700 | [diff] [blame] | 1238 | config ANON_INODES |
| 1239 | bool |
| 1240 | |
Mike Frysinger | 657a520 | 2013-04-30 15:28:45 -0700 | [diff] [blame] | 1241 | config HAVE_UID16 |
| 1242 | bool |
| 1243 | |
| 1244 | config SYSCTL_EXCEPTION_TRACE |
| 1245 | bool |
| 1246 | help |
| 1247 | Enable support for /proc/sys/debug/exception-trace. |
| 1248 | |
| 1249 | config SYSCTL_ARCH_UNALIGN_NO_WARN |
| 1250 | bool |
| 1251 | help |
| 1252 | Enable support for /proc/sys/kernel/ignore-unaligned-usertrap |
| 1253 | Allows arch to define/use @no_unaligned_warning to possibly warn |
| 1254 | about unaligned access emulation going on under the hood. |
| 1255 | |
| 1256 | config SYSCTL_ARCH_UNALIGN_ALLOW |
| 1257 | bool |
| 1258 | help |
| 1259 | Enable support for /proc/sys/kernel/unaligned-trap |
| 1260 | Allows arches to define/use @unaligned_enabled to runtime toggle |
| 1261 | the unaligned access emulation. |
| 1262 | see arch/parisc/kernel/unaligned.c for reference |
| 1263 | |
| 1264 | config HOTPLUG |
| 1265 | def_bool y |
| 1266 | |
| 1267 | config HAVE_PCSPKR_PLATFORM |
| 1268 | bool |
| 1269 | |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1270 | menuconfig EXPERT |
| 1271 | bool "Configure standard kernel features (expert users)" |
Josh Triplett | f505c55 | 2011-06-05 18:23:58 -0700 | [diff] [blame] | 1272 | # Unhide debug options, to make the on-by-default options visible |
| 1273 | select DEBUG_KERNEL |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1274 | help |
| 1275 | This option allows certain base kernel options and settings |
| 1276 | to be disabled or tweaked. This is for specialized |
| 1277 | environments which can tolerate a "non-standard" kernel. |
| 1278 | Only use this if you really know what you are doing. |
| 1279 | |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 1280 | config UID16 |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1281 | bool "Enable 16-bit UID system calls" if EXPERT |
Catalin Marinas | af1839e | 2012-10-08 16:28:08 -0700 | [diff] [blame] | 1282 | depends on HAVE_UID16 |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 1283 | default y |
| 1284 | help |
| 1285 | This enables the legacy 16-bit UID syscall wrappers. |
| 1286 | |
Eric W. Biederman | b89a817 | 2006-09-27 01:51:04 -0700 | [diff] [blame] | 1287 | config SYSCTL_SYSCALL |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1288 | bool "Sysctl syscall support" if EXPERT |
Eric W. Biederman | 26a7034 | 2009-11-05 05:26:41 -0800 | [diff] [blame] | 1289 | depends on PROC_SYSCTL |
WANG Cong | c736de6 | 2011-11-02 13:39:25 -0700 | [diff] [blame] | 1290 | default n |
Eric W. Biederman | b89a817 | 2006-09-27 01:51:04 -0700 | [diff] [blame] | 1291 | select SYSCTL |
| 1292 | ---help--- |
Eric W. Biederman | 13bb7e3 | 2006-11-08 17:44:51 -0800 | [diff] [blame] | 1293 | sys_sysctl uses binary paths that have been found challenging |
| 1294 | to properly maintain and use. The interface in /proc/sys |
| 1295 | using paths with ascii names is now the primary path to this |
| 1296 | information. |
Eric W. Biederman | b89a817 | 2006-09-27 01:51:04 -0700 | [diff] [blame] | 1297 | |
Eric W. Biederman | 13bb7e3 | 2006-11-08 17:44:51 -0800 | [diff] [blame] | 1298 | Almost nothing using the binary sysctl interface so if you are |
| 1299 | trying to save some space it is probably safe to disable this, |
| 1300 | making your kernel marginally smaller. |
Eric W. Biederman | b89a817 | 2006-09-27 01:51:04 -0700 | [diff] [blame] | 1301 | |
WANG Cong | c736de6 | 2011-11-02 13:39:25 -0700 | [diff] [blame] | 1302 | If unsure say N here. |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 1303 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1304 | config KALLSYMS |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1305 | bool "Load all symbols for debugging/ksymoops" if EXPERT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1306 | default y |
| 1307 | help |
| 1308 | Say Y here to let the kernel print out symbolic crash information and |
| 1309 | symbolic stack backtraces. This increases the size of the kernel |
| 1310 | somewhat, as all symbols have to be loaded into the kernel image. |
| 1311 | |
| 1312 | config KALLSYMS_ALL |
| 1313 | bool "Include all symbols in kallsyms" |
| 1314 | depends on DEBUG_KERNEL && KALLSYMS |
| 1315 | help |
Artem Bityutskiy | 71a83ec | 2011-04-05 13:24:57 +0300 | [diff] [blame] | 1316 | Normally kallsyms only contains the symbols of functions for nicer |
| 1317 | OOPS messages and backtraces (i.e., symbols from the text and inittext |
| 1318 | sections). This is sufficient for most cases. And only in very rare |
| 1319 | cases (e.g., when a debugger is used) all symbols are required (e.g., |
| 1320 | names of variables from the data sections, etc). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1321 | |
Artem Bityutskiy | 71a83ec | 2011-04-05 13:24:57 +0300 | [diff] [blame] | 1322 | This option makes sure that all symbols are loaded into the kernel |
| 1323 | image (i.e., symbols from all sections) in cost of increased kernel |
| 1324 | size (depending on the kernel configuration, it may be 300KiB or |
| 1325 | something like this). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1326 | |
Artem Bityutskiy | 71a83ec | 2011-04-05 13:24:57 +0300 | [diff] [blame] | 1327 | Say N unless you really need all symbols. |
Matt Mackall | d59745c | 2005-05-01 08:59:02 -0700 | [diff] [blame] | 1328 | |
| 1329 | config PRINTK |
| 1330 | default y |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1331 | bool "Enable support for printk" if EXPERT |
Frederic Weisbecker | 74876a9 | 2012-10-12 18:00:23 +0200 | [diff] [blame] | 1332 | select IRQ_WORK |
Matt Mackall | d59745c | 2005-05-01 08:59:02 -0700 | [diff] [blame] | 1333 | help |
| 1334 | This option enables normal printk support. Removing it |
| 1335 | eliminates most of the message strings from the kernel image |
| 1336 | and makes the kernel more or less silent. As this makes it |
| 1337 | very difficult to diagnose system problems, saying N here is |
| 1338 | strongly discouraged. |
| 1339 | |
Matt Mackall | c8538a7 | 2005-05-01 08:59:01 -0700 | [diff] [blame] | 1340 | config BUG |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1341 | bool "BUG() support" if EXPERT |
Matt Mackall | c8538a7 | 2005-05-01 08:59:01 -0700 | [diff] [blame] | 1342 | default y |
| 1343 | help |
| 1344 | Disabling this option eliminates support for BUG and WARN, reducing |
| 1345 | the size of your kernel image and potentially quietly ignoring |
| 1346 | numerous fatal conditions. You should only consider disabling this |
| 1347 | option for embedded systems with no facilities for reporting errors. |
| 1348 | Just say Y. |
| 1349 | |
Matt Mackall | 708e9a7 | 2006-01-08 01:05:25 -0800 | [diff] [blame] | 1350 | config ELF_CORE |
Alex Kelly | 046d662 | 2012-10-04 17:15:23 -0700 | [diff] [blame] | 1351 | depends on COREDUMP |
Matt Mackall | 708e9a7 | 2006-01-08 01:05:25 -0800 | [diff] [blame] | 1352 | default y |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1353 | bool "Enable ELF core dumps" if EXPERT |
Matt Mackall | 708e9a7 | 2006-01-08 01:05:25 -0800 | [diff] [blame] | 1354 | help |
| 1355 | Enable support for generating core dumps. Disabling saves about 4k. |
| 1356 | |
Ralf Baechle | 8761f1a | 2011-06-01 19:05:09 +0100 | [diff] [blame] | 1357 | |
Stas Sergeev | e5e1d3c | 2008-05-07 12:39:56 +0200 | [diff] [blame] | 1358 | config PCSPKR_PLATFORM |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1359 | bool "Enable PC-Speaker support" if EXPERT |
Ralf Baechle | 8761f1a | 2011-06-01 19:05:09 +0100 | [diff] [blame] | 1360 | depends on HAVE_PCSPKR_PLATFORM |
Ralf Baechle | 15f304b | 2011-06-01 19:04:59 +0100 | [diff] [blame] | 1361 | select I8253_LOCK |
Stas Sergeev | e5e1d3c | 2008-05-07 12:39:56 +0200 | [diff] [blame] | 1362 | default y |
| 1363 | help |
| 1364 | This option allows to disable the internal PC-Speaker |
| 1365 | support, saving some memory. |
| 1366 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1367 | config BASE_FULL |
| 1368 | default y |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1369 | bool "Enable full-sized data structures for core" if EXPERT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1370 | help |
| 1371 | Disabling this option reduces the size of miscellaneous core |
| 1372 | kernel data structures. This saves memory on small machines, |
| 1373 | but may reduce performance. |
| 1374 | |
| 1375 | config FUTEX |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1376 | bool "Enable futex support" if EXPERT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1377 | default y |
Ingo Molnar | 23f78d4a | 2006-06-27 02:54:53 -0700 | [diff] [blame] | 1378 | select RT_MUTEXES |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1379 | help |
| 1380 | Disabling this option will cause the kernel to be built without |
| 1381 | support for "fast userspace mutexes". The resulting kernel may not |
| 1382 | run glibc-based applications correctly. |
| 1383 | |
| 1384 | config EPOLL |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1385 | bool "Enable eventpoll support" if EXPERT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1386 | default y |
Adrian Bunk | 448e3ce | 2007-07-31 00:39:10 -0700 | [diff] [blame] | 1387 | select ANON_INODES |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1388 | help |
| 1389 | Disabling this option will cause the kernel to be built without |
| 1390 | support for epoll family of system calls. |
| 1391 | |
Davide Libenzi | fba2afa | 2007-05-10 22:23:13 -0700 | [diff] [blame] | 1392 | config SIGNALFD |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1393 | bool "Enable signalfd() system call" if EXPERT |
Adrian Bunk | 448e3ce | 2007-07-31 00:39:10 -0700 | [diff] [blame] | 1394 | select ANON_INODES |
Davide Libenzi | fba2afa | 2007-05-10 22:23:13 -0700 | [diff] [blame] | 1395 | default y |
| 1396 | help |
| 1397 | Enable the signalfd() system call that allows to receive signals |
| 1398 | on a file descriptor. |
| 1399 | |
| 1400 | If unsure, say Y. |
| 1401 | |
Davide Libenzi | b215e28 | 2007-05-10 22:23:16 -0700 | [diff] [blame] | 1402 | config TIMERFD |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1403 | bool "Enable timerfd() system call" if EXPERT |
Adrian Bunk | 448e3ce | 2007-07-31 00:39:10 -0700 | [diff] [blame] | 1404 | select ANON_INODES |
Davide Libenzi | b215e28 | 2007-05-10 22:23:16 -0700 | [diff] [blame] | 1405 | default y |
| 1406 | help |
| 1407 | Enable the timerfd() system call that allows to receive timer |
| 1408 | events on a file descriptor. |
| 1409 | |
| 1410 | If unsure, say Y. |
| 1411 | |
Davide Libenzi | e1ad746 | 2007-05-10 22:23:19 -0700 | [diff] [blame] | 1412 | config EVENTFD |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1413 | bool "Enable eventfd() system call" if EXPERT |
Adrian Bunk | 448e3ce | 2007-07-31 00:39:10 -0700 | [diff] [blame] | 1414 | select ANON_INODES |
Davide Libenzi | e1ad746 | 2007-05-10 22:23:19 -0700 | [diff] [blame] | 1415 | default y |
| 1416 | help |
| 1417 | Enable the eventfd() system call that allows to receive both |
| 1418 | kernel notification (ie. KAIO) or userspace notifications. |
| 1419 | |
| 1420 | If unsure, say Y. |
| 1421 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1422 | config SHMEM |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1423 | bool "Use full shmem filesystem" if EXPERT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1424 | default y |
| 1425 | depends on MMU |
| 1426 | help |
| 1427 | The shmem is an internal filesystem used to manage shared memory. |
| 1428 | It is backed by swap and manages resource limits. It is also exported |
| 1429 | to userspace as tmpfs if TMPFS is enabled. Disabling this |
| 1430 | option replaces shmem and tmpfs with the much simpler ramfs code, |
| 1431 | which may be appropriate on small systems without swap. |
| 1432 | |
Thomas Petazzoni | ebf3f09 | 2008-10-15 22:05:12 -0700 | [diff] [blame] | 1433 | config AIO |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1434 | bool "Enable AIO support" if EXPERT |
Thomas Petazzoni | ebf3f09 | 2008-10-15 22:05:12 -0700 | [diff] [blame] | 1435 | default y |
| 1436 | help |
| 1437 | This option enables POSIX asynchronous I/O which may by used |
Mike Frysinger | 657a520 | 2013-04-30 15:28:45 -0700 | [diff] [blame] | 1438 | by some high performance threaded applications. Disabling |
| 1439 | this option saves about 7k. |
| 1440 | |
| 1441 | config PCI_QUIRKS |
| 1442 | default y |
| 1443 | bool "Enable PCI quirk workarounds" if EXPERT |
| 1444 | depends on PCI |
| 1445 | help |
| 1446 | This enables workarounds for various PCI chipset |
| 1447 | bugs/quirks. Disable this only if your target machine is |
| 1448 | unaffected by PCI quirks. |
Thomas Petazzoni | ebf3f09 | 2008-10-15 22:05:12 -0700 | [diff] [blame] | 1449 | |
Randy Dunlap | 6befe5f | 2011-04-26 12:33:21 -0700 | [diff] [blame] | 1450 | config EMBEDDED |
| 1451 | bool "Embedded system" |
| 1452 | select EXPERT |
| 1453 | help |
| 1454 | This option should be enabled if compiling the kernel for |
| 1455 | an embedded system so certain expert options are available |
| 1456 | for configuration. |
| 1457 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1458 | config HAVE_PERF_EVENTS |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1459 | bool |
Mike Frysinger | 018df72 | 2009-06-12 13:17:43 -0400 | [diff] [blame] | 1460 | help |
| 1461 | See tools/perf/design.txt for details. |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1462 | |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 1463 | config PERF_USE_VMALLOC |
| 1464 | bool |
| 1465 | help |
| 1466 | See tools/perf/design.txt for details |
| 1467 | |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1468 | menu "Kernel Performance Events And Counters" |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1469 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1470 | config PERF_EVENTS |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1471 | bool "Kernel performance events and counters" |
Robert Richter | 392d65a | 2012-04-05 18:24:44 +0200 | [diff] [blame] | 1472 | default y if PROFILING |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1473 | depends on HAVE_PERF_EVENTS |
Ingo Molnar | 4c59e46 | 2008-12-08 19:38:33 +0100 | [diff] [blame] | 1474 | select ANON_INODES |
Peter Zijlstra | e360adb | 2010-10-14 14:01:34 +0800 | [diff] [blame] | 1475 | select IRQ_WORK |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1476 | help |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1477 | Enable kernel support for various performance events provided |
| 1478 | by software and hardware. |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1479 | |
Thadeu Lima de Souza Cascardo | dd77038 | 2009-10-30 19:32:25 -0200 | [diff] [blame] | 1480 | Software events are supported either built-in or via the |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1481 | use of generic tracepoints. |
| 1482 | |
| 1483 | Most modern CPUs support performance events via performance |
| 1484 | counter registers. These registers count the number of certain |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1485 | types of hw events: such as instructions executed, cachemisses |
| 1486 | suffered, or branches mis-predicted - without slowing down the |
| 1487 | kernel or applications. These registers can also trigger interrupts |
| 1488 | when a threshold number of events have passed - and can thus be |
| 1489 | used to profile the code that runs on that CPU. |
| 1490 | |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1491 | The Linux Performance Event subsystem provides an abstraction of |
Thadeu Lima de Souza Cascardo | dd77038 | 2009-10-30 19:32:25 -0200 | [diff] [blame] | 1492 | these software and hardware event capabilities, available via a |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1493 | system call and used by the "perf" utility in tools/perf/. It |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1494 | provides per task and per CPU counters, and it provides event |
| 1495 | capabilities on top of those. |
| 1496 | |
| 1497 | Say Y if unsure. |
| 1498 | |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 1499 | config DEBUG_PERF_USE_VMALLOC |
| 1500 | default n |
| 1501 | bool "Debug: use vmalloc to back perf mmap() buffers" |
| 1502 | depends on PERF_EVENTS && DEBUG_KERNEL |
| 1503 | select PERF_USE_VMALLOC |
| 1504 | help |
| 1505 | Use vmalloc memory to back perf mmap() buffers. |
| 1506 | |
| 1507 | Mostly useful for debugging the vmalloc code on platforms |
| 1508 | that don't require it. |
| 1509 | |
| 1510 | Say N if unsure. |
| 1511 | |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1512 | endmenu |
| 1513 | |
Christoph Lameter | f8891e5 | 2006-06-30 01:55:45 -0700 | [diff] [blame] | 1514 | config VM_EVENT_COUNTERS |
| 1515 | default y |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1516 | bool "Enable VM event counters for /proc/vmstat" if EXPERT |
Christoph Lameter | f8891e5 | 2006-06-30 01:55:45 -0700 | [diff] [blame] | 1517 | help |
Paul Jackson | 2aea4fb | 2006-12-22 01:06:10 -0800 | [diff] [blame] | 1518 | VM event counters are needed for event counts to be shown. |
| 1519 | This option allows the disabling of the VM event counters |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1520 | on EXPERT systems. /proc/vmstat will only show page counts |
Paul Jackson | 2aea4fb | 2006-12-22 01:06:10 -0800 | [diff] [blame] | 1521 | if VM event counters are disabled. |
Christoph Lameter | f8891e5 | 2006-06-30 01:55:45 -0700 | [diff] [blame] | 1522 | |
Christoph Lameter | 41ecc55 | 2007-05-09 02:32:44 -0700 | [diff] [blame] | 1523 | config SLUB_DEBUG |
| 1524 | default y |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1525 | bool "Enable SLUB debugging support" if EXPERT |
Christoph Lameter | f6acb63 | 2008-04-29 16:16:06 -0700 | [diff] [blame] | 1526 | depends on SLUB && SYSFS |
Christoph Lameter | 41ecc55 | 2007-05-09 02:32:44 -0700 | [diff] [blame] | 1527 | help |
| 1528 | SLUB has extensive debug support features. Disabling these can |
| 1529 | result in significant savings in code size. This also disables |
| 1530 | SLUB sysfs support. /sys/slab will not exist and there will be |
| 1531 | no support for cache validation etc. |
| 1532 | |
Randy Dunlap | b943c46 | 2009-03-10 12:55:46 -0700 | [diff] [blame] | 1533 | config COMPAT_BRK |
| 1534 | bool "Disable heap randomization" |
| 1535 | default y |
| 1536 | help |
| 1537 | Randomizing heap placement makes heap exploits harder, but it |
| 1538 | also breaks ancient binaries (including anything libc5 based). |
| 1539 | This option changes the bootup default to heap randomization |
Matt LaPlante | 692105b | 2009-01-26 11:12:25 +0100 | [diff] [blame] | 1540 | disabled, and can be overridden at runtime by setting |
Randy Dunlap | b943c46 | 2009-03-10 12:55:46 -0700 | [diff] [blame] | 1541 | /proc/sys/kernel/randomize_va_space to 2. |
| 1542 | |
| 1543 | On non-ancient distros (post-2000 ones) N is usually a safe choice. |
| 1544 | |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1545 | choice |
| 1546 | prompt "Choose SLAB allocator" |
Christoph Lameter | a0acd82 | 2007-07-17 04:03:32 -0700 | [diff] [blame] | 1547 | default SLUB |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1548 | help |
| 1549 | This option allows to select a slab allocator. |
| 1550 | |
| 1551 | config SLAB |
| 1552 | bool "SLAB" |
| 1553 | help |
| 1554 | The regular slab allocator that is established and known to work |
Christoph Lameter | 3401388 | 2007-05-09 02:32:47 -0700 | [diff] [blame] | 1555 | well in all environments. It organizes cache hot objects in |
Simon Arlott | 02f5621 | 2008-11-05 22:18:19 +0000 | [diff] [blame] | 1556 | per cpu and per node queues. |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1557 | |
| 1558 | config SLUB |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1559 | bool "SLUB (Unqueued Allocator)" |
| 1560 | help |
| 1561 | SLUB is a slab allocator that minimizes cache line usage |
| 1562 | instead of managing queues of cached objects (SLAB approach). |
| 1563 | Per cpu caching is realized using slabs of objects instead |
| 1564 | of queues of objects. SLUB can use memory efficiently |
Simon Arlott | 02f5621 | 2008-11-05 22:18:19 +0000 | [diff] [blame] | 1565 | and has enhanced diagnostics. SLUB is the default choice for |
| 1566 | a slab allocator. |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1567 | |
| 1568 | config SLOB |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1569 | depends on EXPERT |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1570 | bool "SLOB (Simple Allocator)" |
| 1571 | help |
Matt Mackall | 3729145 | 2008-02-04 22:29:38 -0800 | [diff] [blame] | 1572 | SLOB replaces the stock allocator with a drastically simpler |
| 1573 | allocator. SLOB is generally more space efficient but |
| 1574 | does not perform as well on large systems. |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1575 | |
| 1576 | endchoice |
| 1577 | |
Jie Zhang | ea63763 | 2009-12-14 18:00:02 -0800 | [diff] [blame] | 1578 | config MMAP_ALLOW_UNINITIALIZED |
| 1579 | bool "Allow mmapped anonymous memory to be uninitialized" |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1580 | depends on EXPERT && !MMU |
Jie Zhang | ea63763 | 2009-12-14 18:00:02 -0800 | [diff] [blame] | 1581 | default n |
| 1582 | help |
| 1583 | Normally, and according to the Linux spec, anonymous memory obtained |
| 1584 | from mmap() has it's contents cleared before it is passed to |
| 1585 | userspace. Enabling this config option allows you to request that |
| 1586 | mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus |
| 1587 | providing a huge performance boost. If this option is not enabled, |
| 1588 | then the flag will be ignored. |
| 1589 | |
| 1590 | This is taken advantage of by uClibc's malloc(), and also by |
| 1591 | ELF-FDPIC binfmt's brk and stack allocator. |
| 1592 | |
| 1593 | Because of the obvious security issues, this option should only be |
| 1594 | enabled on embedded devices where you control what is run in |
| 1595 | userspace. Since that isn't generally a problem on no-MMU systems, |
| 1596 | it is normally safe to say Y here. |
| 1597 | |
| 1598 | See Documentation/nommu-mmap.txt for more information. |
| 1599 | |
Mathieu Desnoyers | 125e564 | 2008-02-02 15:10:36 -0500 | [diff] [blame] | 1600 | config PROFILING |
Robert Richter | b309a29 | 2010-02-26 15:01:23 +0100 | [diff] [blame] | 1601 | bool "Profiling support" |
Mathieu Desnoyers | 125e564 | 2008-02-02 15:10:36 -0500 | [diff] [blame] | 1602 | help |
| 1603 | Say Y here to enable the extended profiling support mechanisms used |
| 1604 | by profilers such as OProfile. |
| 1605 | |
Ingo Molnar | 5f87f11 | 2008-07-23 14:15:22 +0200 | [diff] [blame] | 1606 | # |
| 1607 | # Place an empty function call at each tracepoint site. Can be |
| 1608 | # dynamically changed for a probe function. |
| 1609 | # |
Mathieu Desnoyers | 97e1c18 | 2008-07-18 12:16:16 -0400 | [diff] [blame] | 1610 | config TRACEPOINTS |
Ingo Molnar | 5f87f11 | 2008-07-23 14:15:22 +0200 | [diff] [blame] | 1611 | bool |
Mathieu Desnoyers | 97e1c18 | 2008-07-18 12:16:16 -0400 | [diff] [blame] | 1612 | |
Mathieu Desnoyers | fb32e03 | 2008-02-02 15:10:33 -0500 | [diff] [blame] | 1613 | source "arch/Kconfig" |
| 1614 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1615 | endmenu # General setup |
| 1616 | |
Dmitry Baryshkov | ee7e551 | 2008-06-29 14:18:46 +0400 | [diff] [blame] | 1617 | config HAVE_GENERIC_DMA_COHERENT |
| 1618 | bool |
| 1619 | default n |
| 1620 | |
Linus Torvalds | 158a962 | 2008-01-02 13:04:48 -0800 | [diff] [blame] | 1621 | config SLABINFO |
| 1622 | bool |
| 1623 | depends on PROC_FS |
Christoph Lameter | 0f389ec | 2008-04-14 18:53:02 +0300 | [diff] [blame] | 1624 | depends on SLAB || SLUB_DEBUG |
Linus Torvalds | 158a962 | 2008-01-02 13:04:48 -0800 | [diff] [blame] | 1625 | default y |
| 1626 | |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 1627 | config RT_MUTEXES |
| 1628 | boolean |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 1629 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1630 | config BASE_SMALL |
| 1631 | int |
| 1632 | default 0 if BASE_FULL |
| 1633 | default 1 if !BASE_FULL |
| 1634 | |
Jan Engelhardt | 66da573 | 2007-07-15 23:39:29 -0700 | [diff] [blame] | 1635 | menuconfig MODULES |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1636 | bool "Enable loadable module support" |
| 1637 | help |
| 1638 | Kernel modules are small pieces of compiled code which can |
| 1639 | be inserted in the running kernel, rather than being |
| 1640 | permanently built into the kernel. You use the "modprobe" |
| 1641 | tool to add (and sometimes remove) them. If you say Y here, |
| 1642 | many parts of the kernel can be built as modules (by |
| 1643 | answering M instead of Y where indicated): this is most |
| 1644 | useful for infrequently used options which are not required |
| 1645 | for booting. For more information, see the man pages for |
| 1646 | modprobe, lsmod, modinfo, insmod and rmmod. |
| 1647 | |
| 1648 | If you say Y here, you will need to run "make |
| 1649 | modules_install" to put the modules under /lib/modules/ |
| 1650 | where modprobe can find them (you may need to be root to do |
| 1651 | this). |
| 1652 | |
| 1653 | If unsure, say Y. |
| 1654 | |
Robert P. J. Day | 0b0de14 | 2008-08-04 13:31:32 -0400 | [diff] [blame] | 1655 | if MODULES |
| 1656 | |
Linus Torvalds | 826e450 | 2008-05-04 17:04:16 -0700 | [diff] [blame] | 1657 | config MODULE_FORCE_LOAD |
| 1658 | bool "Forced module loading" |
Linus Torvalds | 826e450 | 2008-05-04 17:04:16 -0700 | [diff] [blame] | 1659 | default n |
| 1660 | help |
Rusty Russell | 91e37a7 | 2008-05-09 16:25:28 +1000 | [diff] [blame] | 1661 | Allow loading of modules without version information (ie. modprobe |
| 1662 | --force). Forced module loading sets the 'F' (forced) taint flag and |
| 1663 | is usually a really bad idea. |
Linus Torvalds | 826e450 | 2008-05-04 17:04:16 -0700 | [diff] [blame] | 1664 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1665 | config MODULE_UNLOAD |
| 1666 | bool "Module unloading" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1667 | help |
| 1668 | Without this option you will not be able to unload any |
| 1669 | modules (note that some modules may not be unloadable |
Denys Vlasenko | f7f5b67 | 2008-07-22 19:24:26 -0500 | [diff] [blame] | 1670 | anyway), which makes your kernel smaller, faster |
| 1671 | and simpler. If unsure, say Y. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1672 | |
| 1673 | config MODULE_FORCE_UNLOAD |
| 1674 | bool "Forced module unloading" |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 1675 | depends on MODULE_UNLOAD |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1676 | help |
| 1677 | This option allows you to force a module to unload, even if the |
| 1678 | kernel believes it is unsafe: the kernel will remove the module |
| 1679 | without waiting for anyone to stop using it (using the -f option to |
| 1680 | rmmod). This is mainly for kernel developers and desperate users. |
| 1681 | If unsure, say N. |
| 1682 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1683 | config MODVERSIONS |
Sam Ravnborg | 0d54164 | 2005-12-26 23:04:02 +0100 | [diff] [blame] | 1684 | bool "Module versioning support" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1685 | help |
| 1686 | Usually, you have to use modules compiled with your kernel. |
| 1687 | Saying Y here makes it sometimes possible to use modules |
| 1688 | compiled for different kernels, by adding enough information |
| 1689 | to the modules to (hopefully) spot any changes which would |
| 1690 | make them incompatible with the kernel you are running. If |
| 1691 | unsure, say N. |
| 1692 | |
| 1693 | config MODULE_SRCVERSION_ALL |
| 1694 | bool "Source checksum for all modules" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1695 | help |
| 1696 | Modules which contain a MODULE_VERSION get an extra "srcversion" |
| 1697 | field inserted into their modinfo section, which contains a |
| 1698 | sum of the source files which made it. This helps maintainers |
| 1699 | see exactly which source was used to build a module (since |
| 1700 | others sometimes change the module source without updating |
| 1701 | the version). With this option, such a "srcversion" field |
| 1702 | will be created for all modules. If unsure, say N. |
| 1703 | |
Rusty Russell | 106a4ee | 2012-09-26 10:09:40 +0100 | [diff] [blame] | 1704 | config MODULE_SIG |
| 1705 | bool "Module signature verification" |
| 1706 | depends on MODULES |
David Howells | 48ba246 | 2012-09-26 10:11:03 +0100 | [diff] [blame] | 1707 | select KEYS |
| 1708 | select CRYPTO |
| 1709 | select ASYMMETRIC_KEY_TYPE |
| 1710 | select ASYMMETRIC_PUBLIC_KEY_SUBTYPE |
| 1711 | select PUBLIC_KEY_ALGO_RSA |
| 1712 | select ASN1 |
| 1713 | select OID_REGISTRY |
| 1714 | select X509_CERTIFICATE_PARSER |
Rusty Russell | 106a4ee | 2012-09-26 10:09:40 +0100 | [diff] [blame] | 1715 | help |
| 1716 | Check modules for valid signatures upon load: the signature |
| 1717 | is simply appended to the module. For more information see |
| 1718 | Documentation/module-signing.txt. |
| 1719 | |
David Howells | ea0b6dc | 2012-09-26 10:09:50 +0100 | [diff] [blame] | 1720 | !!!WARNING!!! If you enable this option, you MUST make sure that the |
| 1721 | module DOES NOT get stripped after being signed. This includes the |
| 1722 | debuginfo strip done by some packagers (such as rpmbuild) and |
| 1723 | inclusion into an initramfs that wants the module size reduced. |
| 1724 | |
Rusty Russell | 106a4ee | 2012-09-26 10:09:40 +0100 | [diff] [blame] | 1725 | config MODULE_SIG_FORCE |
| 1726 | bool "Require modules to be validly signed" |
| 1727 | depends on MODULE_SIG |
| 1728 | help |
| 1729 | Reject unsigned modules or signed modules for which we don't have a |
| 1730 | key. Without this, such modules will simply taint the kernel. |
David Howells | ea0b6dc | 2012-09-26 10:09:50 +0100 | [diff] [blame] | 1731 | |
Michal Marek | d9d8d7e | 2013-01-25 13:41:31 +1030 | [diff] [blame] | 1732 | config MODULE_SIG_ALL |
| 1733 | bool "Automatically sign all modules" |
| 1734 | default y |
| 1735 | depends on MODULE_SIG |
| 1736 | help |
| 1737 | Sign all modules during make modules_install. Without this option, |
| 1738 | modules must be signed manually, using the scripts/sign-file tool. |
| 1739 | |
| 1740 | comment "Do not forget to sign required modules with scripts/sign-file" |
| 1741 | depends on MODULE_SIG_FORCE && !MODULE_SIG_ALL |
| 1742 | |
David Howells | ea0b6dc | 2012-09-26 10:09:50 +0100 | [diff] [blame] | 1743 | choice |
| 1744 | prompt "Which hash algorithm should modules be signed with?" |
| 1745 | depends on MODULE_SIG |
| 1746 | help |
| 1747 | This determines which sort of hashing algorithm will be used during |
| 1748 | signature generation. This algorithm _must_ be built into the kernel |
| 1749 | directly so that signature verification can take place. It is not |
| 1750 | possible to load a signed module containing the algorithm to check |
| 1751 | the signature on that module. |
| 1752 | |
| 1753 | config MODULE_SIG_SHA1 |
| 1754 | bool "Sign modules with SHA-1" |
| 1755 | select CRYPTO_SHA1 |
| 1756 | |
| 1757 | config MODULE_SIG_SHA224 |
| 1758 | bool "Sign modules with SHA-224" |
| 1759 | select CRYPTO_SHA256 |
| 1760 | |
| 1761 | config MODULE_SIG_SHA256 |
| 1762 | bool "Sign modules with SHA-256" |
| 1763 | select CRYPTO_SHA256 |
| 1764 | |
| 1765 | config MODULE_SIG_SHA384 |
| 1766 | bool "Sign modules with SHA-384" |
| 1767 | select CRYPTO_SHA512 |
| 1768 | |
| 1769 | config MODULE_SIG_SHA512 |
| 1770 | bool "Sign modules with SHA-512" |
| 1771 | select CRYPTO_SHA512 |
| 1772 | |
| 1773 | endchoice |
| 1774 | |
Michal Marek | 2275367 | 2013-01-25 13:41:00 +1030 | [diff] [blame] | 1775 | config MODULE_SIG_HASH |
| 1776 | string |
| 1777 | depends on MODULE_SIG |
| 1778 | default "sha1" if MODULE_SIG_SHA1 |
| 1779 | default "sha224" if MODULE_SIG_SHA224 |
| 1780 | default "sha256" if MODULE_SIG_SHA256 |
| 1781 | default "sha384" if MODULE_SIG_SHA384 |
| 1782 | default "sha512" if MODULE_SIG_SHA512 |
| 1783 | |
Robert P. J. Day | 0b0de14 | 2008-08-04 13:31:32 -0400 | [diff] [blame] | 1784 | endif # MODULES |
| 1785 | |
Rusty Russell | 98a79d6 | 2008-12-13 21:19:41 +1030 | [diff] [blame] | 1786 | config INIT_ALL_POSSIBLE |
| 1787 | bool |
| 1788 | help |
Rusty Russell | 5f054e3 | 2012-03-29 15:38:31 +1030 | [diff] [blame] | 1789 | Back when each arch used to define their own cpu_online_mask and |
| 1790 | cpu_possible_mask, some of them chose to initialize cpu_possible_mask |
Rusty Russell | 98a79d6 | 2008-12-13 21:19:41 +1030 | [diff] [blame] | 1791 | with all 1s, and others with all 0s. When they were centralised, |
| 1792 | 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] | 1793 | and have several arch maintainers pursuing me down dark alleys. |
Rusty Russell | 98a79d6 | 2008-12-13 21:19:41 +1030 | [diff] [blame] | 1794 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1795 | config STOP_MACHINE |
| 1796 | bool |
| 1797 | default y |
| 1798 | depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU |
| 1799 | help |
| 1800 | Need stop_machine() primitive. |
Jens Axboe | 3a65dfe | 2005-11-04 08:43:35 +0100 | [diff] [blame] | 1801 | |
Jens Axboe | 3a65dfe | 2005-11-04 08:43:35 +0100 | [diff] [blame] | 1802 | source "block/Kconfig" |
Avi Kivity | e98c320 | 2007-10-16 23:27:31 -0700 | [diff] [blame] | 1803 | |
| 1804 | config PREEMPT_NOTIFIERS |
| 1805 | bool |
Paul E. McKenney | e260be6 | 2008-01-25 21:08:24 +0100 | [diff] [blame] | 1806 | |
Steffen Klassert | 16295be | 2010-01-06 19:47:10 +1100 | [diff] [blame] | 1807 | config PADATA |
| 1808 | depends on SMP |
| 1809 | bool |
| 1810 | |
Andi Kleen | 754b7b6 | 2012-10-04 17:11:27 -0700 | [diff] [blame] | 1811 | # Can be selected by architectures with broken toolchains |
| 1812 | # that get confused by correct const<->read_only section |
| 1813 | # mappings |
| 1814 | config BROKEN_RODATA |
| 1815 | bool |
| 1816 | |
David Howells | 4520c6a | 2012-09-21 23:31:13 +0100 | [diff] [blame] | 1817 | config ASN1 |
| 1818 | tristate |
| 1819 | help |
| 1820 | Build a simple ASN.1 grammar compiler that produces a bytecode output |
| 1821 | that can be interpreted by the ASN.1 stream decoder and used to |
| 1822 | inform it as to what tags are to be expected in a stream and what |
| 1823 | functions to call on what tags. |
| 1824 | |
Thomas Gleixner | 6beb000 | 2009-11-09 15:21:34 +0000 | [diff] [blame] | 1825 | source "kernel/Kconfig.locks" |