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 | |
Jiri Slaby | 4bb1667 | 2013-05-22 10:56:24 +0200 | [diff] [blame] | 56 | config COMPILE_TEST |
| 57 | bool "Compile also drivers which will not load" |
| 58 | default n |
| 59 | help |
| 60 | Some drivers can be compiled on a different platform than they are |
| 61 | intended to be run on. Despite they cannot be loaded there (or even |
| 62 | when they load they cannot be used due to missing HW support), |
| 63 | developers still, opposing to distributors, might want to build such |
| 64 | drivers to compile-test them. |
| 65 | |
| 66 | If you are a developer and want to build everything available, say Y |
| 67 | here. If you are a user/distributor, say N here to exclude useless |
| 68 | drivers to be distributed. |
| 69 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | config LOCALVERSION |
| 71 | string "Local version - append to kernel release" |
| 72 | help |
| 73 | Append an extra string to the end of your kernel version. |
| 74 | This will show up when you type uname, for example. |
| 75 | The string you set here will be appended after the contents of |
| 76 | any files with a filename matching localversion* in your |
| 77 | object and source tree, in that order. Your total string can |
| 78 | be a maximum of 64 characters. |
| 79 | |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 80 | config LOCALVERSION_AUTO |
| 81 | bool "Automatically append version information to the version string" |
| 82 | default y |
| 83 | help |
| 84 | 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] | 85 | release tree by looking for git tags that belong to the current |
| 86 | top of tree revision. |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 87 | |
| 88 | 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] | 89 | 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] | 90 | appended after any matching localversion* files, and after the value |
Robert P. J. Day | 6e5a542 | 2007-05-01 23:08:11 +0200 | [diff] [blame] | 91 | set in CONFIG_LOCALVERSION. |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 92 | |
Robert P. J. Day | 6e5a542 | 2007-05-01 23:08:11 +0200 | [diff] [blame] | 93 | (The actual string used here is the first eight characters produced |
| 94 | by running the command: |
| 95 | |
| 96 | $ git rev-parse --verify HEAD |
| 97 | |
| 98 | which is done within the script "scripts/setlocalversion".) |
Ryan Anderson | aaebf43 | 2005-07-31 04:57:49 -0400 | [diff] [blame] | 99 | |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 100 | config HAVE_KERNEL_GZIP |
| 101 | bool |
| 102 | |
| 103 | config HAVE_KERNEL_BZIP2 |
| 104 | bool |
| 105 | |
| 106 | config HAVE_KERNEL_LZMA |
| 107 | bool |
| 108 | |
Lasse Collin | 3ebe124 | 2011-01-12 17:01:23 -0800 | [diff] [blame] | 109 | config HAVE_KERNEL_XZ |
| 110 | bool |
| 111 | |
Albin Tonnerre | 7dd65fe | 2010-01-08 14:42:42 -0800 | [diff] [blame] | 112 | config HAVE_KERNEL_LZO |
| 113 | bool |
| 114 | |
Kyungsik Lee | e76e1fd | 2013-07-08 16:01:46 -0700 | [diff] [blame] | 115 | config HAVE_KERNEL_LZ4 |
| 116 | bool |
| 117 | |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 118 | choice |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 119 | prompt "Kernel compression mode" |
| 120 | default KERNEL_GZIP |
H. Peter Anvin | 2d3c627 | 2013-11-14 21:43:47 -0800 | [diff] [blame] | 121 | depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 122 | help |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 123 | The linux kernel is a kind of self-extracting executable. |
| 124 | Several compression algorithms are available, which differ |
| 125 | in efficiency, compression and decompression speed. |
| 126 | Compression speed is only relevant when building a kernel. |
| 127 | Decompression speed is relevant at each boot. |
| 128 | |
| 129 | If you have any problems with bzip2 or lzma compressed |
| 130 | kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older |
| 131 | version of this functionality (bzip2 only), for 2.4, was |
| 132 | supplied by Christian Ludwig) |
| 133 | |
| 134 | High compression options are mostly useful for users, who |
| 135 | are low on disk space (embedded systems), but for whom ram |
| 136 | size matters less. |
| 137 | |
| 138 | If in doubt, select 'gzip' |
| 139 | |
| 140 | config KERNEL_GZIP |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 141 | bool "Gzip" |
| 142 | depends on HAVE_KERNEL_GZIP |
| 143 | help |
Albin Tonnerre | 7dd65fe | 2010-01-08 14:42:42 -0800 | [diff] [blame] | 144 | The old and tried gzip compression. It provides a good balance |
| 145 | between compression ratio and decompression speed. |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 146 | |
| 147 | config KERNEL_BZIP2 |
| 148 | bool "Bzip2" |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 149 | depends on HAVE_KERNEL_BZIP2 |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 150 | help |
| 151 | Its compression ratio and speed is intermediate. |
Randy Dunlap | 0a4dd35 | 2012-05-31 16:26:46 -0700 | [diff] [blame] | 152 | Decompression speed is slowest among the choices. The kernel |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 153 | size is about 10% smaller with bzip2, in comparison to gzip. |
| 154 | Bzip2 uses a large amount of memory. For modern kernels you |
| 155 | will need at least 8MB RAM or more for booting. |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 156 | |
| 157 | config KERNEL_LZMA |
H. Peter Anvin | 2e9f3bd | 2009-01-04 15:41:25 -0800 | [diff] [blame] | 158 | bool "LZMA" |
| 159 | depends on HAVE_KERNEL_LZMA |
| 160 | help |
Randy Dunlap | 0a4dd35 | 2012-05-31 16:26:46 -0700 | [diff] [blame] | 161 | This compression algorithm's ratio is best. Decompression speed |
| 162 | is between gzip and bzip2. Compression is slowest. |
| 163 | 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] | 164 | |
Lasse Collin | 3ebe124 | 2011-01-12 17:01:23 -0800 | [diff] [blame] | 165 | config KERNEL_XZ |
| 166 | bool "XZ" |
| 167 | depends on HAVE_KERNEL_XZ |
| 168 | help |
| 169 | XZ uses the LZMA2 algorithm and instruction set specific |
| 170 | BCJ filters which can improve compression ratio of executable |
| 171 | code. The size of the kernel is about 30% smaller with XZ in |
| 172 | comparison to gzip. On architectures for which there is a BCJ |
| 173 | filter (i386, x86_64, ARM, IA-64, PowerPC, and SPARC), XZ |
| 174 | will create a few percent smaller kernel than plain LZMA. |
| 175 | |
| 176 | The speed is about the same as with LZMA: The decompression |
| 177 | speed of XZ is better than that of bzip2 but worse than gzip |
| 178 | and LZO. Compression is slow. |
| 179 | |
Albin Tonnerre | 7dd65fe | 2010-01-08 14:42:42 -0800 | [diff] [blame] | 180 | config KERNEL_LZO |
| 181 | bool "LZO" |
| 182 | depends on HAVE_KERNEL_LZO |
| 183 | help |
Randy Dunlap | 0a4dd35 | 2012-05-31 16:26:46 -0700 | [diff] [blame] | 184 | Its compression ratio is the poorest among the choices. The kernel |
Stephan Sperber | 681b304 | 2010-07-14 11:23:08 +0200 | [diff] [blame] | 185 | size is about 10% bigger than gzip; however its speed |
Albin Tonnerre | 7dd65fe | 2010-01-08 14:42:42 -0800 | [diff] [blame] | 186 | (both compression and decompression) is the fastest. |
| 187 | |
Kyungsik Lee | e76e1fd | 2013-07-08 16:01:46 -0700 | [diff] [blame] | 188 | config KERNEL_LZ4 |
| 189 | bool "LZ4" |
| 190 | depends on HAVE_KERNEL_LZ4 |
| 191 | help |
| 192 | LZ4 is an LZ77-type compressor with a fixed, byte-oriented encoding. |
| 193 | A preliminary version of LZ4 de/compression tool is available at |
| 194 | <https://code.google.com/p/lz4/>. |
| 195 | |
| 196 | Its compression ratio is worse than LZO. The size of the kernel |
| 197 | is about 8% bigger than LZO. But the decompression speed is |
| 198 | faster than LZO. |
| 199 | |
Alain Knaff | 30d65db | 2009-01-04 22:46:17 +0100 | [diff] [blame] | 200 | endchoice |
| 201 | |
Josh Triplett | bd5dc17 | 2011-06-15 15:08:28 -0700 | [diff] [blame] | 202 | config DEFAULT_HOSTNAME |
| 203 | string "Default hostname" |
| 204 | default "(none)" |
| 205 | help |
| 206 | This option determines the default system hostname before userspace |
| 207 | calls sethostname(2). The kernel traditionally uses "(none)" here, |
| 208 | but you may wish to use a different default here to make a minimal |
| 209 | system more usable with less configuration. |
| 210 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 211 | config SWAP |
| 212 | bool "Support for paging of anonymous memory (swap)" |
David Howells | 9361401 | 2006-09-30 20:45:40 +0200 | [diff] [blame] | 213 | depends on MMU && BLOCK |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | default y |
| 215 | help |
| 216 | This option allows you to choose whether you want to have support |
Jesper Juhl | 92c3504 | 2006-01-15 02:40:08 +0100 | [diff] [blame] | 217 | 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] | 218 | used to provide more virtual memory than the actual RAM present |
| 219 | in your computer. If unsure say Y. |
| 220 | |
| 221 | config SYSVIPC |
| 222 | bool "System V IPC" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | ---help--- |
| 224 | Inter Process Communication is a suite of library functions and |
| 225 | system calls which let processes (running programs) synchronize and |
| 226 | exchange information. It is generally considered to be a good thing, |
| 227 | and some programs won't run unless you say Y here. In particular, if |
| 228 | you want to run the DOS emulator dosemu under Linux (read the |
| 229 | DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>), |
| 230 | you'll need to say Y here. |
| 231 | |
| 232 | You can find documentation about IPC with "info ipc" and also in |
| 233 | section 6.4 of the Linux Programmer's Guide, available from |
| 234 | <http://www.tldp.org/guides.html>. |
| 235 | |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 236 | config SYSVIPC_SYSCTL |
| 237 | bool |
| 238 | depends on SYSVIPC |
| 239 | depends on SYSCTL |
| 240 | default y |
| 241 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 242 | config POSIX_MQUEUE |
| 243 | bool "POSIX Message Queues" |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 244 | depends on NET |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 245 | ---help--- |
| 246 | POSIX variant of message queues is a part of IPC. In POSIX message |
| 247 | queues every message has a priority which decides about succession |
| 248 | of receiving it by a process. If you want to compile and run |
| 249 | 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] | 250 | queues (functions mq_*) say Y here. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 251 | |
| 252 | POSIX message queues are visible as a filesystem called 'mqueue' |
| 253 | and can be mounted somewhere if you want to do filesystem |
| 254 | operations on message queues. |
| 255 | |
| 256 | If unsure, say Y. |
| 257 | |
Serge E. Hallyn | bdc8e5f | 2009-04-06 19:01:11 -0700 | [diff] [blame] | 258 | config POSIX_MQUEUE_SYSCTL |
| 259 | bool |
| 260 | depends on POSIX_MQUEUE |
| 261 | depends on SYSCTL |
| 262 | default y |
| 263 | |
Konstantin Khlebnikov | 226b4cc | 2014-06-04 16:10:50 -0700 | [diff] [blame] | 264 | config CROSS_MEMORY_ATTACH |
| 265 | bool "Enable process_vm_readv/writev syscalls" |
| 266 | depends on MMU |
| 267 | default y |
| 268 | help |
| 269 | Enabling this option adds the system calls process_vm_readv and |
| 270 | process_vm_writev which allow a process with the correct privileges |
Geert Uytterhoeven | a2a368d | 2014-08-12 13:46:11 -0700 | [diff] [blame] | 271 | to directly read from or write to another process' address space. |
Konstantin Khlebnikov | 226b4cc | 2014-06-04 16:10:50 -0700 | [diff] [blame] | 272 | See the man page for more details. |
| 273 | |
Aneesh Kumar K.V | 990d6c2 | 2011-01-29 18:43:26 +0530 | [diff] [blame] | 274 | config FHANDLE |
Andi Kleen | f76be61 | 2016-04-01 14:31:40 -0700 | [diff] [blame] | 275 | bool "open by fhandle syscalls" if EXPERT |
Aneesh Kumar K.V | 990d6c2 | 2011-01-29 18:43:26 +0530 | [diff] [blame] | 276 | select EXPORTFS |
Andi Kleen | f76be61 | 2016-04-01 14:31:40 -0700 | [diff] [blame] | 277 | default y |
Aneesh Kumar K.V | 990d6c2 | 2011-01-29 18:43:26 +0530 | [diff] [blame] | 278 | help |
| 279 | If you say Y here, a user level program will be able to map |
| 280 | file names to handle and then later use the handle for |
| 281 | different file system operations. This is useful in implementing |
| 282 | userspace file servers, which now track files using handles instead |
| 283 | of names. The handle would remain the same even if file names |
| 284 | get renamed. Enables open_by_handle_at(2) and name_to_handle_at(2) |
| 285 | syscalls. |
| 286 | |
Josh Triplett | 69369a7 | 2014-04-03 14:48:27 -0700 | [diff] [blame] | 287 | config USELIB |
| 288 | bool "uselib syscall" |
Riku Voipio | b2113a4 | 2016-01-15 16:58:13 -0800 | [diff] [blame] | 289 | def_bool ALPHA || M68K || SPARC || X86_32 || IA32_EMULATION |
Josh Triplett | 69369a7 | 2014-04-03 14:48:27 -0700 | [diff] [blame] | 290 | help |
| 291 | This option enables the uselib syscall, a system call used in the |
| 292 | dynamic linker from libc5 and earlier. glibc does not use this |
| 293 | system call. If you intend to run programs built on libc5 or |
| 294 | earlier, you may need to enable this syscall. Current systems |
| 295 | running glibc can safely disable this. |
| 296 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 297 | config AUDIT |
| 298 | bool "Auditing support" |
Chris Wright | 804a6a49 | 2005-05-11 10:52:45 +0100 | [diff] [blame] | 299 | depends on NET |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | help |
| 301 | Enable auditing infrastructure that can be used with another |
| 302 | kernel subsystem, such as SELinux (which requires this for |
Paul Moore | cb74ed2 | 2016-01-13 09:18:55 -0500 | [diff] [blame] | 303 | logging of avc messages output). System call auditing is included |
| 304 | on architectures which support it. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 305 | |
AKASHI Takahiro | 7a01772 | 2014-02-25 18:16:24 +0900 | [diff] [blame] | 306 | config HAVE_ARCH_AUDITSYSCALL |
| 307 | bool |
| 308 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 309 | config AUDITSYSCALL |
Paul Moore | cb74ed2 | 2016-01-13 09:18:55 -0500 | [diff] [blame] | 310 | def_bool y |
AKASHI Takahiro | 7a01772 | 2014-02-25 18:16:24 +0900 | [diff] [blame] | 311 | depends on AUDIT && HAVE_ARCH_AUDITSYSCALL |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 312 | |
Eric Paris | 939a67f | 2009-12-17 20:12:06 -0500 | [diff] [blame] | 313 | config AUDIT_WATCH |
| 314 | def_bool y |
| 315 | depends on AUDITSYSCALL |
| 316 | select FSNOTIFY |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 317 | |
Al Viro | 74c3cbe | 2007-07-22 08:04:18 -0400 | [diff] [blame] | 318 | config AUDIT_TREE |
| 319 | def_bool y |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 320 | depends on AUDITSYSCALL |
Eric Paris | 28a3a7e | 2009-12-17 20:12:05 -0500 | [diff] [blame] | 321 | select FSNOTIFY |
Al Viro | 74c3cbe | 2007-07-22 08:04:18 -0400 | [diff] [blame] | 322 | |
Thomas Gleixner | d9817eb | 2010-09-27 12:45:59 +0000 | [diff] [blame] | 323 | source "kernel/irq/Kconfig" |
Thomas Gleixner | 764e0da | 2012-05-21 23:16:18 +0200 | [diff] [blame] | 324 | source "kernel/time/Kconfig" |
Thomas Gleixner | d9817eb | 2010-09-27 12:45:59 +0000 | [diff] [blame] | 325 | |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 326 | menu "CPU/Task time and stats accounting" |
| 327 | |
Frederic Weisbecker | abf917c | 2012-07-25 07:56:04 +0200 | [diff] [blame] | 328 | config VIRT_CPU_ACCOUNTING |
| 329 | bool |
| 330 | |
Frederic Weisbecker | fdf9c35 | 2012-09-09 14:56:31 +0200 | [diff] [blame] | 331 | choice |
| 332 | prompt "Cputime accounting" |
| 333 | default TICK_CPU_ACCOUNTING if !PPC64 |
Stephen Rothwell | 02fc8d3 | 2013-02-08 14:19:38 +1100 | [diff] [blame] | 334 | default VIRT_CPU_ACCOUNTING_NATIVE if PPC64 |
Frederic Weisbecker | fdf9c35 | 2012-09-09 14:56:31 +0200 | [diff] [blame] | 335 | |
| 336 | # Kind of a stub config for the pure tick based cputime accounting |
| 337 | config TICK_CPU_ACCOUNTING |
| 338 | bool "Simple tick based cputime accounting" |
Frederic Weisbecker | c58b0df | 2013-04-26 15:16:31 +0200 | [diff] [blame] | 339 | depends on !S390 && !NO_HZ_FULL |
Frederic Weisbecker | fdf9c35 | 2012-09-09 14:56:31 +0200 | [diff] [blame] | 340 | help |
| 341 | This is the basic tick based cputime accounting that maintains |
| 342 | statistics about user, system and idle time spent on per jiffies |
| 343 | granularity. |
| 344 | |
| 345 | If unsure, say Y. |
| 346 | |
Frederic Weisbecker | abf917c | 2012-07-25 07:56:04 +0200 | [diff] [blame] | 347 | config VIRT_CPU_ACCOUNTING_NATIVE |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 348 | bool "Deterministic task and CPU time accounting" |
Frederic Weisbecker | c58b0df | 2013-04-26 15:16:31 +0200 | [diff] [blame] | 349 | depends on HAVE_VIRT_CPU_ACCOUNTING && !NO_HZ_FULL |
Frederic Weisbecker | abf917c | 2012-07-25 07:56:04 +0200 | [diff] [blame] | 350 | select VIRT_CPU_ACCOUNTING |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 351 | help |
| 352 | Select this option to enable more accurate task and CPU time |
| 353 | accounting. This is done by reading a CPU counter on each |
| 354 | kernel entry and exit and on transitions within the kernel |
| 355 | between system, softirq and hardirq state, so there is a |
| 356 | small performance impact. In the case of s390 or IBM POWER > 5, |
| 357 | this also enables accounting of stolen time on logically-partitioned |
| 358 | systems. |
| 359 | |
Frederic Weisbecker | abf917c | 2012-07-25 07:56:04 +0200 | [diff] [blame] | 360 | config VIRT_CPU_ACCOUNTING_GEN |
| 361 | bool "Full dynticks CPU time accounting" |
Kevin Hilman | ff3fb25 | 2013-09-16 15:28:19 -0700 | [diff] [blame] | 362 | depends on HAVE_CONTEXT_TRACKING |
Kevin Hilman | 554b000 | 2013-09-16 15:28:21 -0700 | [diff] [blame] | 363 | depends on HAVE_VIRT_CPU_ACCOUNTING_GEN |
Frederic Weisbecker | abf917c | 2012-07-25 07:56:04 +0200 | [diff] [blame] | 364 | select VIRT_CPU_ACCOUNTING |
| 365 | select CONTEXT_TRACKING |
| 366 | help |
| 367 | Select this option to enable task and CPU time accounting on full |
| 368 | dynticks systems. This accounting is implemented by watching every |
| 369 | kernel-user boundaries using the context tracking subsystem. |
| 370 | The accounting is thus performed at the expense of some significant |
| 371 | overhead. |
| 372 | |
| 373 | For now this is only useful if you are working on the full |
| 374 | dynticks subsystem development. |
| 375 | |
| 376 | If unsure, say N. |
| 377 | |
Frederic Weisbecker | fdf9c35 | 2012-09-09 14:56:31 +0200 | [diff] [blame] | 378 | config IRQ_TIME_ACCOUNTING |
| 379 | bool "Fine granularity task level IRQ time accounting" |
Frederic Weisbecker | c58b0df | 2013-04-26 15:16:31 +0200 | [diff] [blame] | 380 | depends on HAVE_IRQ_TIME_ACCOUNTING && !NO_HZ_FULL |
Frederic Weisbecker | fdf9c35 | 2012-09-09 14:56:31 +0200 | [diff] [blame] | 381 | help |
| 382 | Select this option to enable fine granularity task irq time |
| 383 | accounting. This is done by reading a timestamp on each |
| 384 | transitions between softirq and hardirq state, so there can be a |
| 385 | small performance impact. |
| 386 | |
| 387 | If in doubt, say N here. |
| 388 | |
| 389 | endchoice |
| 390 | |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 391 | config BSD_PROCESS_ACCT |
| 392 | bool "BSD Process Accounting" |
Iulia Manda | 2813893 | 2015-04-15 16:16:41 -0700 | [diff] [blame] | 393 | depends on MULTIUSER |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 394 | help |
| 395 | If you say Y here, a user level program will be able to instruct the |
| 396 | kernel (via a special system call) to write process accounting |
| 397 | information to a file: whenever a process exits, information about |
| 398 | that process will be appended to the file by the kernel. The |
| 399 | information includes things such as creation time, owning user, |
| 400 | command name, memory usage, controlling terminal etc. (the complete |
| 401 | list is in the struct acct in <file:include/linux/acct.h>). It is |
| 402 | up to the user level program to do useful things with this |
| 403 | information. This is generally a good idea, so say Y. |
| 404 | |
| 405 | config BSD_PROCESS_ACCT_V3 |
| 406 | bool "BSD Process Accounting version 3 file format" |
| 407 | depends on BSD_PROCESS_ACCT |
| 408 | default n |
| 409 | help |
| 410 | If you say Y here, the process accounting information is written |
| 411 | in a new file format that also logs the process IDs of each |
| 412 | process and it's parent. Note that this file format is incompatible |
| 413 | with previous v0/v1/v2 file formats, so you will need updated tools |
| 414 | for processing it. A preliminary version of these tools is available |
| 415 | at <http://www.gnu.org/software/acct/>. |
| 416 | |
| 417 | config TASKSTATS |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 418 | bool "Export task/process statistics through netlink" |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 419 | depends on NET |
Iulia Manda | 2813893 | 2015-04-15 16:16:41 -0700 | [diff] [blame] | 420 | depends on MULTIUSER |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 421 | default n |
| 422 | help |
| 423 | Export selected statistics for tasks/processes through the |
| 424 | generic netlink interface. Unlike BSD process accounting, the |
| 425 | statistics are available during the lifetime of tasks/processes as |
| 426 | responses to commands. Like BSD accounting, they are sent to user |
| 427 | space on task exit. |
| 428 | |
| 429 | Say N if unsure. |
| 430 | |
| 431 | config TASK_DELAY_ACCT |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 432 | bool "Enable per-task delay accounting" |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 433 | depends on TASKSTATS |
Naveen N. Rao | f6db834 | 2015-06-25 23:53:37 +0530 | [diff] [blame] | 434 | select SCHED_INFO |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 435 | help |
| 436 | Collect information on time spent by a task waiting for system |
| 437 | resources like cpu, synchronous block I/O completion and swapping |
| 438 | in pages. Such statistics can help in setting a task's priorities |
| 439 | relative to other tasks for cpu, io, rss limits etc. |
| 440 | |
| 441 | Say N if unsure. |
| 442 | |
| 443 | config TASK_XACCT |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 444 | bool "Enable extended accounting over taskstats" |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 445 | depends on TASKSTATS |
| 446 | help |
| 447 | Collect extended task accounting data and send the data |
| 448 | to userland for processing over the taskstats interface. |
| 449 | |
| 450 | Say N if unsure. |
| 451 | |
| 452 | config TASK_IO_ACCOUNTING |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 453 | bool "Enable per-task storage I/O accounting" |
Frederic Weisbecker | 391dc69 | 2012-09-09 14:22:07 +0200 | [diff] [blame] | 454 | depends on TASK_XACCT |
| 455 | help |
| 456 | Collect information on the number of bytes of storage I/O which this |
| 457 | task has caused. |
| 458 | |
| 459 | Say N if unsure. |
| 460 | |
| 461 | endmenu # "CPU/Task time and stats accounting" |
| 462 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 463 | menu "RCU Subsystem" |
| 464 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 465 | config TREE_RCU |
Pranith Kumar | e72aeaf | 2015-04-21 17:29:42 -0400 | [diff] [blame] | 466 | bool |
| 467 | default y if !PREEMPT && SMP |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 468 | help |
| 469 | This option selects the RCU implementation that is |
| 470 | designed for very large SMP system with hundreds or |
Paul E. McKenney | c17ef45 | 2009-06-23 17:12:47 -0700 | [diff] [blame] | 471 | thousands of CPUs. It also scales down nicely to |
| 472 | smaller systems. |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 473 | |
Pranith Kumar | 28f6569 | 2014-09-22 14:00:48 -0400 | [diff] [blame] | 474 | config PREEMPT_RCU |
Pranith Kumar | e72aeaf | 2015-04-21 17:29:42 -0400 | [diff] [blame] | 475 | bool |
| 476 | default y if PREEMPT |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 477 | help |
| 478 | This option selects the RCU implementation that is |
| 479 | designed for very large SMP systems with hundreds or |
| 480 | thousands of CPUs, but for which real-time response |
Paul E. McKenney | bbe3eae | 2009-09-13 09:15:08 -0700 | [diff] [blame] | 481 | is also required. It also scales down nicely to |
| 482 | smaller systems. |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 483 | |
Paul E. McKenney | 9fc52d8 | 2013-01-08 15:48:33 -0800 | [diff] [blame] | 484 | Select this option if you are unsure. |
| 485 | |
Paul E. McKenney | 9b1d82f | 2009-10-25 19:03:50 -0700 | [diff] [blame] | 486 | config TINY_RCU |
Pranith Kumar | e72aeaf | 2015-04-21 17:29:42 -0400 | [diff] [blame] | 487 | bool |
| 488 | default y if !PREEMPT && !SMP |
Paul E. McKenney | 9b1d82f | 2009-10-25 19:03:50 -0700 | [diff] [blame] | 489 | help |
| 490 | This option selects the RCU implementation that is |
| 491 | designed for UP systems from which real-time response |
| 492 | is not required. This option greatly reduces the |
| 493 | memory footprint of RCU. |
| 494 | |
Paul E. McKenney | 78cae10 | 2015-04-20 12:19:45 -0700 | [diff] [blame] | 495 | config RCU_EXPERT |
| 496 | bool "Make expert-level adjustments to RCU configuration" |
| 497 | default n |
| 498 | help |
| 499 | This option needs to be enabled if you wish to make |
| 500 | expert-level adjustments to RCU configuration. By default, |
| 501 | no such adjustments can be made, which has the often-beneficial |
| 502 | side-effect of preventing "make oldconfig" from asking you all |
| 503 | sorts of detailed questions about how you would like numerous |
| 504 | obscure RCU options to be set up. |
| 505 | |
| 506 | Say Y if you need to make expert-level adjustments to RCU. |
| 507 | |
| 508 | Say N if you are unsure. |
| 509 | |
Pranith Kumar | 83fe27e | 2014-12-05 11:24:45 -0500 | [diff] [blame] | 510 | config SRCU |
| 511 | bool |
| 512 | help |
| 513 | This option selects the sleepable version of RCU. This version |
| 514 | permits arbitrary sleeping or blocking within RCU read-side critical |
| 515 | sections. |
| 516 | |
Paul E. McKenney | 8315f42 | 2014-06-27 13:42:20 -0700 | [diff] [blame] | 517 | config TASKS_RCU |
Paul E. McKenney | 82d0f4c | 2015-04-20 05:42:50 -0700 | [diff] [blame] | 518 | bool |
Paul E. McKenney | 8315f42 | 2014-06-27 13:42:20 -0700 | [diff] [blame] | 519 | default n |
Paul E. McKenney | 570dd3c | 2016-06-15 08:56:53 -0700 | [diff] [blame^] | 520 | depends on !UML |
Pranith Kumar | 83fe27e | 2014-12-05 11:24:45 -0500 | [diff] [blame] | 521 | select SRCU |
Paul E. McKenney | 8315f42 | 2014-06-27 13:42:20 -0700 | [diff] [blame] | 522 | help |
| 523 | This option enables a task-based RCU implementation that uses |
| 524 | only voluntary context switch (not preemption!), idle, and |
| 525 | user-mode execution as quiescent states. |
| 526 | |
Paul E. McKenney | 6bfc09e | 2012-10-19 12:49:17 -0700 | [diff] [blame] | 527 | config RCU_STALL_COMMON |
Pranith Kumar | 28f6569 | 2014-09-22 14:00:48 -0400 | [diff] [blame] | 528 | def_bool ( TREE_RCU || PREEMPT_RCU || RCU_TRACE ) |
Paul E. McKenney | 6bfc09e | 2012-10-19 12:49:17 -0700 | [diff] [blame] | 529 | help |
| 530 | This option enables RCU CPU stall code that is common between |
| 531 | the TINY and TREE variants of RCU. The purpose is to allow |
| 532 | the tiny variants to disable RCU CPU stall warnings, while |
| 533 | making these warnings mandatory for the tree variants. |
| 534 | |
Frederic Weisbecker | 91d1aa43 | 2012-11-27 19:33:25 +0100 | [diff] [blame] | 535 | config CONTEXT_TRACKING |
| 536 | bool |
| 537 | |
Frederic Weisbecker | 91d1aa43 | 2012-11-27 19:33:25 +0100 | [diff] [blame] | 538 | config CONTEXT_TRACKING_FORCE |
| 539 | bool "Force context tracking" |
| 540 | depends on CONTEXT_TRACKING |
Frederic Weisbecker | d84d27a | 2013-07-24 21:59:29 +0200 | [diff] [blame] | 541 | default y if !NO_HZ_FULL |
Frederic Weisbecker | 1fd2b44 | 2012-07-11 20:26:40 +0200 | [diff] [blame] | 542 | help |
Frederic Weisbecker | d84d27a | 2013-07-24 21:59:29 +0200 | [diff] [blame] | 543 | The major pre-requirement for full dynticks to work is to |
| 544 | support the context tracking subsystem. But there are also |
| 545 | other dependencies to provide in order to make the full |
| 546 | dynticks working. |
| 547 | |
| 548 | This option stands for testing when an arch implements the |
| 549 | context tracking backend but doesn't yet fullfill all the |
| 550 | requirements to make the full dynticks feature working. |
| 551 | Without the full dynticks, there is no way to test the support |
| 552 | for context tracking and the subsystems that rely on it: RCU |
| 553 | userspace extended quiescent state and tickless cputime |
| 554 | accounting. This option copes with the absence of the full |
| 555 | dynticks subsystem by forcing the context tracking on all |
| 556 | CPUs in the system. |
| 557 | |
Paul Gortmaker | 99c8b1e | 2013-10-24 10:07:47 -0400 | [diff] [blame] | 558 | Say Y only if you're working on the development of an |
Frederic Weisbecker | d84d27a | 2013-07-24 21:59:29 +0200 | [diff] [blame] | 559 | architecture backend for the context tracking. |
| 560 | |
| 561 | Say N otherwise, this option brings an overhead that you |
| 562 | don't want in production. |
| 563 | |
Frederic Weisbecker | d677124 | 2012-10-11 01:48:28 +0200 | [diff] [blame] | 564 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 565 | config RCU_FANOUT |
| 566 | int "Tree-based hierarchical RCU fanout value" |
| 567 | range 2 64 if 64BIT |
| 568 | range 2 32 if !64BIT |
Paul E. McKenney | 05c5df3 | 2015-04-20 14:27:43 -0700 | [diff] [blame] | 569 | depends on (TREE_RCU || PREEMPT_RCU) && RCU_EXPERT |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 570 | default 64 if 64BIT |
| 571 | default 32 if !64BIT |
| 572 | help |
| 573 | This option controls the fanout of hierarchical implementations |
| 574 | of RCU, allowing RCU to work efficiently on machines with |
Paul E. McKenney | 4d87ffa | 2010-08-04 17:31:12 -0700 | [diff] [blame] | 575 | large numbers of CPUs. This value must be at least the fourth |
| 576 | root of NR_CPUS, which allows NR_CPUS to be insanely large. |
| 577 | The default value of RCU_FANOUT should be used for production |
| 578 | systems, but if you are stress-testing the RCU implementation |
| 579 | itself, small RCU_FANOUT values allow you to test large-system |
| 580 | code paths on small(er) systems. |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 581 | |
| 582 | Select a specific number if testing RCU itself. |
| 583 | Take the default if unsure. |
| 584 | |
Paul E. McKenney | 8932a63 | 2012-04-19 12:20:14 -0700 | [diff] [blame] | 585 | config RCU_FANOUT_LEAF |
| 586 | int "Tree-based hierarchical RCU leaf-level fanout value" |
Paul E. McKenney | 8739c5c | 2015-04-20 18:27:54 -0700 | [diff] [blame] | 587 | range 2 64 if 64BIT |
| 588 | range 2 32 if !64BIT |
Paul E. McKenney | 47d631a | 2015-04-21 09:12:13 -0700 | [diff] [blame] | 589 | depends on (TREE_RCU || PREEMPT_RCU) && RCU_EXPERT |
Paul E. McKenney | 8932a63 | 2012-04-19 12:20:14 -0700 | [diff] [blame] | 590 | default 16 |
| 591 | help |
| 592 | This option controls the leaf-level fanout of hierarchical |
| 593 | implementations of RCU, and allows trading off cache misses |
| 594 | against lock contention. Systems that synchronize their |
| 595 | scheduling-clock interrupts for energy-efficiency reasons will |
| 596 | want the default because the smaller leaf-level fanout keeps |
| 597 | lock contention levels acceptably low. Very large systems |
| 598 | (hundreds or thousands of CPUs) will instead want to set this |
| 599 | value to the maximum value possible in order to reduce the |
| 600 | number of cache misses incurred during RCU's grace-period |
| 601 | initialization. These systems tend to run CPU-bound, and thus |
| 602 | are not helped by synchronized interrupts, and thus tend to |
| 603 | skew them, which reduces lock contention enough that large |
| 604 | leaf-level fanouts work well. |
| 605 | |
| 606 | Select a specific number if testing RCU itself. |
| 607 | |
| 608 | Select the maximum permissible value for large systems. |
| 609 | |
| 610 | Take the default if unsure. |
| 611 | |
Paul E. McKenney | 8bd93a2 | 2010-02-22 17:04:59 -0800 | [diff] [blame] | 612 | config RCU_FAST_NO_HZ |
| 613 | bool "Accelerate last non-dyntick-idle CPU's grace periods" |
Paul E. McKenney | 78cae10 | 2015-04-20 12:19:45 -0700 | [diff] [blame] | 614 | depends on NO_HZ_COMMON && SMP && RCU_EXPERT |
Paul E. McKenney | 8bd93a2 | 2010-02-22 17:04:59 -0800 | [diff] [blame] | 615 | default n |
| 616 | help |
Paul E. McKenney | c0f4dfd | 2012-12-28 11:30:36 -0800 | [diff] [blame] | 617 | This option permits CPUs to enter dynticks-idle state even if |
| 618 | they have RCU callbacks queued, and prevents RCU from waking |
| 619 | these CPUs up more than roughly once every four jiffies (by |
| 620 | default, you can adjust this using the rcutree.rcu_idle_gp_delay |
| 621 | parameter), thus improving energy efficiency. On the other |
| 622 | hand, this option increases the duration of RCU grace periods, |
| 623 | for example, slowing down synchronize_rcu(). |
Paul E. McKenney | 8bd93a2 | 2010-02-22 17:04:59 -0800 | [diff] [blame] | 624 | |
Paul E. McKenney | c0f4dfd | 2012-12-28 11:30:36 -0800 | [diff] [blame] | 625 | Say Y if energy efficiency is critically important, and you |
| 626 | don't care about increased grace-period durations. |
Paul E. McKenney | 8bd93a2 | 2010-02-22 17:04:59 -0800 | [diff] [blame] | 627 | |
| 628 | Say N if you are unsure. |
| 629 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 630 | config TREE_RCU_TRACE |
Pranith Kumar | 28f6569 | 2014-09-22 14:00:48 -0400 | [diff] [blame] | 631 | def_bool RCU_TRACE && ( TREE_RCU || PREEMPT_RCU ) |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 632 | select DEBUG_FS |
| 633 | help |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 634 | This option provides tracing for the TREE_RCU and |
Pranith Kumar | 28f6569 | 2014-09-22 14:00:48 -0400 | [diff] [blame] | 635 | PREEMPT_RCU implementations, permitting Makefile to |
Paul E. McKenney | f41d911 | 2009-08-22 13:56:52 -0700 | [diff] [blame] | 636 | trivially select kernel/rcutree_trace.c. |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 637 | |
Paul E. McKenney | 24278d1 | 2010-09-27 17:25:23 -0700 | [diff] [blame] | 638 | config RCU_BOOST |
| 639 | bool "Enable RCU priority boosting" |
Paul E. McKenney | 78cae10 | 2015-04-20 12:19:45 -0700 | [diff] [blame] | 640 | depends on RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT |
Paul E. McKenney | 24278d1 | 2010-09-27 17:25:23 -0700 | [diff] [blame] | 641 | default n |
| 642 | help |
| 643 | This option boosts the priority of preempted RCU readers that |
| 644 | block the current preemptible RCU grace period for too long. |
| 645 | This option also prevents heavy loads from blocking RCU |
| 646 | callback invocation for all flavors of RCU. |
| 647 | |
| 648 | Say Y here if you are working with real-time apps or heavy loads |
| 649 | Say N here if you are unsure. |
| 650 | |
Clark Williams | 21871d7 | 2014-09-12 21:21:09 -0500 | [diff] [blame] | 651 | config RCU_KTHREAD_PRIO |
| 652 | int "Real-time priority to use for RCU worker threads" |
Paul E. McKenney | a94844b | 2014-12-12 07:37:48 -0800 | [diff] [blame] | 653 | range 1 99 if RCU_BOOST |
| 654 | range 0 99 if !RCU_BOOST |
| 655 | default 1 if RCU_BOOST |
| 656 | default 0 if !RCU_BOOST |
Paul E. McKenney | 26730f5 | 2015-04-21 09:22:14 -0700 | [diff] [blame] | 657 | depends on RCU_EXPERT |
Paul E. McKenney | 24278d1 | 2010-09-27 17:25:23 -0700 | [diff] [blame] | 658 | help |
Clark Williams | 21871d7 | 2014-09-12 21:21:09 -0500 | [diff] [blame] | 659 | This option specifies the SCHED_FIFO priority value that will be |
| 660 | assigned to the rcuc/n and rcub/n threads and is also the value |
| 661 | used for RCU_BOOST (if enabled). If you are working with a |
| 662 | real-time application that has one or more CPU-bound threads |
| 663 | running at a real-time priority level, you should set |
| 664 | RCU_KTHREAD_PRIO to a priority higher than the highest-priority |
| 665 | real-time CPU-bound application thread. The default RCU_KTHREAD_PRIO |
| 666 | value of 1 is appropriate in the common case, which is real-time |
Paul E. McKenney | c933664 | 2012-04-18 16:20:18 -0700 | [diff] [blame] | 667 | applications that do not have any CPU-bound threads. |
| 668 | |
| 669 | Some real-time applications might not have a single real-time |
| 670 | thread that saturates a given CPU, but instead might have |
| 671 | multiple real-time threads that, taken together, fully utilize |
Clark Williams | 21871d7 | 2014-09-12 21:21:09 -0500 | [diff] [blame] | 672 | that CPU. In this case, you should set RCU_KTHREAD_PRIO to |
Paul E. McKenney | c933664 | 2012-04-18 16:20:18 -0700 | [diff] [blame] | 673 | a priority higher than the lowest-priority thread that is |
| 674 | conspiring to prevent the CPU from running any non-real-time |
| 675 | tasks. For example, if one thread at priority 10 and another |
| 676 | thread at priority 5 are between themselves fully consuming |
Clark Williams | 21871d7 | 2014-09-12 21:21:09 -0500 | [diff] [blame] | 677 | the CPU time on a given CPU, then RCU_KTHREAD_PRIO should be |
Paul E. McKenney | c933664 | 2012-04-18 16:20:18 -0700 | [diff] [blame] | 678 | set to priority 6 or higher. |
Paul E. McKenney | 24278d1 | 2010-09-27 17:25:23 -0700 | [diff] [blame] | 679 | |
| 680 | Specify the real-time priority, or take the default if unsure. |
| 681 | |
| 682 | config RCU_BOOST_DELAY |
| 683 | int "Milliseconds to delay boosting after RCU grace-period start" |
| 684 | range 0 3000 |
| 685 | depends on RCU_BOOST |
| 686 | default 500 |
| 687 | help |
| 688 | This option specifies the time to wait after the beginning of |
| 689 | a given grace period before priority-boosting preempted RCU |
| 690 | readers blocking that grace period. Note that any RCU reader |
| 691 | blocking an expedited RCU grace period is boosted immediately. |
| 692 | |
| 693 | Accept the default if unsure. |
| 694 | |
Paul E. McKenney | 3fbfbf7 | 2012-08-19 21:35:53 -0700 | [diff] [blame] | 695 | config RCU_NOCB_CPU |
Paul E. McKenney | 9a5739d | 2013-03-28 20:48:36 -0700 | [diff] [blame] | 696 | bool "Offload RCU callback processing from boot-selected CPUs" |
Pranith Kumar | 28f6569 | 2014-09-22 14:00:48 -0400 | [diff] [blame] | 697 | depends on TREE_RCU || PREEMPT_RCU |
Paul E. McKenney | be55fa2 | 2015-06-02 05:29:18 -0700 | [diff] [blame] | 698 | depends on RCU_EXPERT || NO_HZ_FULL |
Paul E. McKenney | 3fbfbf7 | 2012-08-19 21:35:53 -0700 | [diff] [blame] | 699 | default n |
| 700 | help |
| 701 | Use this option to reduce OS jitter for aggressive HPC or |
| 702 | real-time workloads. It can also be used to offload RCU |
| 703 | callback invocation to energy-efficient CPUs in battery-powered |
| 704 | asymmetric multiprocessors. |
| 705 | |
| 706 | This option offloads callback invocation from the set of |
| 707 | CPUs specified at boot time by the rcu_nocbs parameter. |
Paul E. McKenney | a488985 | 2012-12-03 08:16:28 -0800 | [diff] [blame] | 708 | For each such CPU, a kthread ("rcuox/N") will be created to |
| 709 | invoke callbacks, where the "N" is the CPU being offloaded, |
| 710 | and where the "x" is "b" for RCU-bh, "p" for RCU-preempt, and |
| 711 | "s" for RCU-sched. Nothing prevents this kthread from running |
| 712 | on the specified CPUs, but (1) the kthreads may be preempted |
| 713 | between each callback, and (2) affinity or cgroups can be used |
| 714 | 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] | 715 | |
Paul E. McKenney | 34ed6246 | 2013-01-07 13:37:42 -0800 | [diff] [blame] | 716 | 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] | 717 | Say N here if you are unsure. |
| 718 | |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 719 | choice |
| 720 | prompt "Build-forced no-CBs CPUs" |
| 721 | default RCU_NOCB_CPU_NONE |
Stefan Hengelein | 4568779 | 2014-09-02 19:55:11 +0200 | [diff] [blame] | 722 | depends on RCU_NOCB_CPU |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 723 | help |
Paul E. McKenney | 676c3dc | 2013-04-30 14:49:42 -0700 | [diff] [blame] | 724 | This option allows no-CBs CPUs (whose RCU callbacks are invoked |
| 725 | from kthreads rather than from softirq context) to be specified |
| 726 | at build time. Additional no-CBs CPUs may be specified by |
| 727 | the rcu_nocbs= boot parameter. |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 728 | |
| 729 | config RCU_NOCB_CPU_NONE |
| 730 | bool "No build_forced no-CBs CPUs" |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 731 | help |
| 732 | This option does not force any of the CPUs to be no-CBs CPUs. |
| 733 | Only CPUs designated by the rcu_nocbs= boot parameter will be |
Paul E. McKenney | 676c3dc | 2013-04-30 14:49:42 -0700 | [diff] [blame] | 734 | no-CBs CPUs, whose RCU callbacks will be invoked by per-CPU |
| 735 | kthreads whose names begin with "rcuo". All other CPUs will |
| 736 | invoke their own RCU callbacks in softirq context. |
| 737 | |
| 738 | Select this option if you want to choose no-CBs CPUs at |
| 739 | boot time, for example, to allow testing of different no-CBs |
| 740 | configurations without having to rebuild the kernel each time. |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 741 | |
| 742 | config RCU_NOCB_CPU_ZERO |
| 743 | bool "CPU 0 is a build_forced no-CBs CPU" |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 744 | help |
Paul E. McKenney | 676c3dc | 2013-04-30 14:49:42 -0700 | [diff] [blame] | 745 | This option forces CPU 0 to be a no-CBs CPU, so that its RCU |
| 746 | callbacks are invoked by a per-CPU kthread whose name begins |
| 747 | with "rcuo". Additional CPUs may be designated as no-CBs |
| 748 | CPUs using the rcu_nocbs= boot parameter will be no-CBs CPUs. |
| 749 | All other CPUs will invoke their own RCU callbacks in softirq |
| 750 | context. |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 751 | |
| 752 | 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] | 753 | or energy-efficiency reasons, but the real reason it exists |
| 754 | is to ensure that randconfig testing covers mixed systems. |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 755 | |
| 756 | config RCU_NOCB_CPU_ALL |
| 757 | bool "All CPUs are build_forced no-CBs CPUs" |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 758 | help |
| 759 | 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] | 760 | boot parameter will be ignored. All CPUs' RCU callbacks will |
| 761 | be executed in the context of per-CPU rcuo kthreads created for |
| 762 | this purpose. Assuming that the kthreads whose names start with |
| 763 | "rcuo" are bound to "housekeeping" CPUs, this reduces OS jitter |
| 764 | on the remaining CPUs, but might decrease memory locality during |
| 765 | RCU-callback invocation, thus potentially degrading throughput. |
Paul E. McKenney | 911af50 | 2013-02-11 10:23:27 -0800 | [diff] [blame] | 766 | |
| 767 | Select this if all CPUs need to be no-CBs CPUs for real-time |
| 768 | or energy-efficiency reasons. |
| 769 | |
| 770 | endchoice |
| 771 | |
Paul E. McKenney | ee42571 | 2015-02-19 10:51:32 -0800 | [diff] [blame] | 772 | config RCU_EXPEDITE_BOOT |
| 773 | bool |
| 774 | default n |
| 775 | help |
| 776 | This option enables expedited grace periods at boot time, |
| 777 | as if rcu_expedite_gp() had been invoked early in boot. |
| 778 | The corresponding rcu_unexpedite_gp() is invoked from |
| 779 | rcu_end_inkernel_boot(), which is intended to be invoked |
| 780 | at the end of the kernel-only boot sequence, just before |
| 781 | init is exec'ed. |
| 782 | |
| 783 | Accept the default if unsure. |
| 784 | |
Mike Travis | c903ff8 | 2009-01-15 12:28:29 -0800 | [diff] [blame] | 785 | endmenu # "RCU Subsystem" |
| 786 | |
Vivek Goyal | de5b56b | 2014-08-08 14:25:41 -0700 | [diff] [blame] | 787 | config BUILD_BIN2C |
| 788 | bool |
| 789 | default n |
| 790 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 791 | config IKCONFIG |
Ross Biro | f2443ab | 2006-09-30 23:27:25 -0700 | [diff] [blame] | 792 | tristate "Kernel .config support" |
Vivek Goyal | de5b56b | 2014-08-08 14:25:41 -0700 | [diff] [blame] | 793 | select BUILD_BIN2C |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 794 | ---help--- |
| 795 | This option enables the complete Linux kernel ".config" file |
| 796 | contents to be saved in the kernel. It provides documentation |
| 797 | of which kernel options are used in a running kernel or in an |
| 798 | on-disk kernel. This information can be extracted from the kernel |
| 799 | image file with the script scripts/extract-ikconfig and used as |
| 800 | input to rebuild the current kernel or to build another kernel. |
| 801 | It can also be extracted from a running kernel by reading |
| 802 | /proc/config.gz if enabled (below). |
| 803 | |
| 804 | config IKCONFIG_PROC |
| 805 | bool "Enable access to .config through /proc/config.gz" |
| 806 | depends on IKCONFIG && PROC_FS |
| 807 | ---help--- |
| 808 | This option enables access to the kernel configuration file |
| 809 | through /proc/config.gz. |
| 810 | |
Alistair John Strachan | 794543a | 2007-05-08 00:31:15 -0700 | [diff] [blame] | 811 | config LOG_BUF_SHIFT |
| 812 | int "Kernel log buffer size (16 => 64KB, 17 => 128KB)" |
Ingo Molnar | fb39f98 | 2015-07-01 10:19:11 +0200 | [diff] [blame] | 813 | range 12 25 |
Adrian Bunk | f17a32e | 2008-04-29 00:58:58 -0700 | [diff] [blame] | 814 | default 17 |
Josh Triplett | 361e9df | 2014-10-03 16:00:54 -0700 | [diff] [blame] | 815 | depends on PRINTK |
Alistair John Strachan | 794543a | 2007-05-08 00:31:15 -0700 | [diff] [blame] | 816 | help |
Luis R. Rodriguez | 23b2899 | 2014-08-06 16:08:56 -0700 | [diff] [blame] | 817 | Select the minimal kernel log buffer size as a power of 2. |
| 818 | The final size is affected by LOG_CPU_MAX_BUF_SHIFT config |
| 819 | parameter, see below. Any higher size also might be forced |
| 820 | by "log_buf_len" boot parameter. |
| 821 | |
Adrian Bunk | f17a32e | 2008-04-29 00:58:58 -0700 | [diff] [blame] | 822 | Examples: |
Luis R. Rodriguez | 23b2899 | 2014-08-06 16:08:56 -0700 | [diff] [blame] | 823 | 17 => 128 KB |
Adrian Bunk | f17a32e | 2008-04-29 00:58:58 -0700 | [diff] [blame] | 824 | 16 => 64 KB |
Luis R. Rodriguez | 23b2899 | 2014-08-06 16:08:56 -0700 | [diff] [blame] | 825 | 15 => 32 KB |
| 826 | 14 => 16 KB |
Alistair John Strachan | 794543a | 2007-05-08 00:31:15 -0700 | [diff] [blame] | 827 | 13 => 8 KB |
| 828 | 12 => 4 KB |
| 829 | |
Luis R. Rodriguez | 23b2899 | 2014-08-06 16:08:56 -0700 | [diff] [blame] | 830 | config LOG_CPU_MAX_BUF_SHIFT |
| 831 | int "CPU kernel log buffer size contribution (13 => 8 KB, 17 => 128KB)" |
Geert Uytterhoeven | 2240a31 | 2014-10-13 15:51:11 -0700 | [diff] [blame] | 832 | depends on SMP |
Luis R. Rodriguez | 23b2899 | 2014-08-06 16:08:56 -0700 | [diff] [blame] | 833 | range 0 21 |
| 834 | default 12 if !BASE_SMALL |
| 835 | default 0 if BASE_SMALL |
Josh Triplett | 361e9df | 2014-10-03 16:00:54 -0700 | [diff] [blame] | 836 | depends on PRINTK |
Luis R. Rodriguez | 23b2899 | 2014-08-06 16:08:56 -0700 | [diff] [blame] | 837 | help |
| 838 | This option allows to increase the default ring buffer size |
| 839 | according to the number of CPUs. The value defines the contribution |
| 840 | of each CPU as a power of 2. The used space is typically only few |
| 841 | lines however it might be much more when problems are reported, |
| 842 | e.g. backtraces. |
| 843 | |
| 844 | The increased size means that a new buffer has to be allocated and |
| 845 | the original static one is unused. It makes sense only on systems |
| 846 | with more CPUs. Therefore this value is used only when the sum of |
| 847 | contributions is greater than the half of the default kernel ring |
| 848 | buffer as defined by LOG_BUF_SHIFT. The default values are set |
| 849 | so that more than 64 CPUs are needed to trigger the allocation. |
| 850 | |
| 851 | Also this option is ignored when "log_buf_len" kernel parameter is |
| 852 | used as it forces an exact (power of two) size of the ring buffer. |
| 853 | |
| 854 | The number of possible CPUs is used for this computation ignoring |
| 855 | hotplugging making the compuation optimal for the the worst case |
| 856 | scenerio while allowing a simple algorithm to be used from bootup. |
| 857 | |
| 858 | Examples shift values and their meaning: |
| 859 | 17 => 128 KB for each CPU |
| 860 | 16 => 64 KB for each CPU |
| 861 | 15 => 32 KB for each CPU |
| 862 | 14 => 16 KB for each CPU |
| 863 | 13 => 8 KB for each CPU |
| 864 | 12 => 4 KB for each CPU |
| 865 | |
Petr Mladek | 427934b | 2016-05-20 17:00:39 -0700 | [diff] [blame] | 866 | config NMI_LOG_BUF_SHIFT |
| 867 | int "Temporary per-CPU NMI log buffer size (12 => 4KB, 13 => 8KB)" |
| 868 | range 10 21 |
| 869 | default 13 |
| 870 | depends on PRINTK_NMI |
| 871 | help |
| 872 | Select the size of a per-CPU buffer where NMI messages are temporary |
| 873 | stored. They are copied to the main log buffer in a safe context |
| 874 | to avoid a deadlock. The value defines the size as a power of 2. |
| 875 | |
| 876 | NMI messages are rare and limited. The largest one is when |
| 877 | a backtrace is printed. It usually fits into 4KB. Select |
| 878 | 8KB if you want to be on the safe side. |
| 879 | |
| 880 | Examples: |
| 881 | 17 => 128 KB for each CPU |
| 882 | 16 => 64 KB for each CPU |
| 883 | 15 => 32 KB for each CPU |
| 884 | 14 => 16 KB for each CPU |
| 885 | 13 => 8 KB for each CPU |
| 886 | 12 => 4 KB for each CPU |
| 887 | |
KAMEZAWA Hiroyuki | 5cdc38f | 2009-01-07 18:07:30 -0800 | [diff] [blame] | 888 | # |
| 889 | # Architectures with an unreliable sched_clock() should select this: |
| 890 | # |
| 891 | config HAVE_UNSTABLE_SCHED_CLOCK |
| 892 | bool |
| 893 | |
Stephen Boyd | 38ff87f | 2013-06-01 23:39:40 -0700 | [diff] [blame] | 894 | config GENERIC_SCHED_CLOCK |
| 895 | bool |
| 896 | |
Andrea Arcangeli | be3a728 | 2012-10-04 01:50:47 +0200 | [diff] [blame] | 897 | # |
| 898 | # For architectures that want to enable the support for NUMA-affine scheduler |
| 899 | # balancing logic: |
| 900 | # |
| 901 | config ARCH_SUPPORTS_NUMA_BALANCING |
| 902 | bool |
| 903 | |
Peter Zijlstra | be5e610 | 2013-11-18 18:27:06 +0100 | [diff] [blame] | 904 | # |
Mel Gorman | 72b252a | 2015-09-04 15:47:32 -0700 | [diff] [blame] | 905 | # For architectures that prefer to flush all TLBs after a number of pages |
| 906 | # are unmapped instead of sending one IPI per page to flush. The architecture |
| 907 | # must provide guarantees on what happens if a clean TLB cache entry is |
| 908 | # written after the unmap. Details are in mm/rmap.c near the check for |
| 909 | # should_defer_flush. The architecture should also consider if the full flush |
| 910 | # and the refill costs are offset by the savings of sending fewer IPIs. |
| 911 | config ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH |
| 912 | bool |
| 913 | |
| 914 | # |
Peter Zijlstra | be5e610 | 2013-11-18 18:27:06 +0100 | [diff] [blame] | 915 | # For architectures that know their GCC __int128 support is sound |
| 916 | # |
| 917 | config ARCH_SUPPORTS_INT128 |
| 918 | bool |
| 919 | |
Andrea Arcangeli | be3a728 | 2012-10-04 01:50:47 +0200 | [diff] [blame] | 920 | # For architectures that (ab)use NUMA to represent different memory regions |
| 921 | # all cpu-local but of different latencies, such as SuperH. |
| 922 | # |
| 923 | config ARCH_WANT_NUMA_VARIABLE_LOCALITY |
| 924 | bool |
| 925 | |
Andrea Arcangeli | be3a728 | 2012-10-04 01:50:47 +0200 | [diff] [blame] | 926 | config NUMA_BALANCING |
| 927 | bool "Memory placement aware NUMA scheduler" |
Andrea Arcangeli | be3a728 | 2012-10-04 01:50:47 +0200 | [diff] [blame] | 928 | depends on ARCH_SUPPORTS_NUMA_BALANCING |
| 929 | depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY |
| 930 | depends on SMP && NUMA && MIGRATION |
| 931 | help |
| 932 | This option adds support for automatic NUMA aware memory/task placement. |
| 933 | The mechanism is quite primitive and is based on migrating memory when |
Paul Gortmaker | 6d56a41 | 2013-08-13 11:06:50 -0400 | [diff] [blame] | 934 | it has references to the node the task is running on. |
Andrea Arcangeli | be3a728 | 2012-10-04 01:50:47 +0200 | [diff] [blame] | 935 | |
| 936 | This system will be inactive on UMA systems. |
| 937 | |
Aneesh Kumar K.V | 6f7c97e | 2014-12-10 15:43:37 -0800 | [diff] [blame] | 938 | config NUMA_BALANCING_DEFAULT_ENABLED |
| 939 | bool "Automatically enable NUMA aware memory/task placement" |
| 940 | default y |
| 941 | depends on NUMA_BALANCING |
| 942 | help |
| 943 | If set, automatic NUMA balancing will be enabled if running on a NUMA |
| 944 | machine. |
| 945 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 946 | menuconfig CGROUPS |
Christoph Jaeger | 6341e62 | 2014-12-20 15:41:11 -0500 | [diff] [blame] | 947 | bool "Control Group support" |
Tejun Heo | 2bd59d4 | 2014-02-11 11:52:49 -0500 | [diff] [blame] | 948 | select KERNFS |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 949 | help |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 950 | This option adds support for grouping sets of processes together, for |
KAMEZAWA Hiroyuki | 5cdc38f | 2009-01-07 18:07:30 -0800 | [diff] [blame] | 951 | use with process control subsystems such as Cpusets, CFS, memory |
| 952 | controls or device isolation. |
| 953 | See |
KAMEZAWA Hiroyuki | 5cdc38f | 2009-01-07 18:07:30 -0800 | [diff] [blame] | 954 | - Documentation/scheduler/sched-design-CFS.txt (CFS) |
Li Zefan | 45ce80f | 2009-01-15 13:50:59 -0800 | [diff] [blame] | 955 | - Documentation/cgroups/ (features for grouping, isolation |
| 956 | and resource control) |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 957 | |
| 958 | Say N if unsure. |
| 959 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 960 | if CGROUPS |
| 961 | |
Johannes Weiner | 3e32cb2 | 2014-12-10 15:42:31 -0800 | [diff] [blame] | 962 | config PAGE_COUNTER |
| 963 | bool |
| 964 | |
Andrew Morton | c255a45 | 2012-07-31 16:43:02 -0700 | [diff] [blame] | 965 | config MEMCG |
Johannes Weiner | a0166ec | 2015-12-17 17:19:56 -0500 | [diff] [blame] | 966 | bool "Memory controller" |
Johannes Weiner | 3e32cb2 | 2014-12-10 15:42:31 -0800 | [diff] [blame] | 967 | select PAGE_COUNTER |
Tejun Heo | 79bd981 | 2013-11-22 18:20:42 -0500 | [diff] [blame] | 968 | select EVENTFD |
Balbir Singh | 00f0b82 | 2008-03-04 14:28:39 -0800 | [diff] [blame] | 969 | help |
Johannes Weiner | a0166ec | 2015-12-17 17:19:56 -0500 | [diff] [blame] | 970 | Provides control over the memory footprint of tasks in a cgroup. |
Balbir Singh | 00f0b82 | 2008-03-04 14:28:39 -0800 | [diff] [blame] | 971 | |
Andrew Morton | c255a45 | 2012-07-31 16:43:02 -0700 | [diff] [blame] | 972 | config MEMCG_SWAP |
Johannes Weiner | a0166ec | 2015-12-17 17:19:56 -0500 | [diff] [blame] | 973 | bool "Swap controller" |
Andrew Morton | c255a45 | 2012-07-31 16:43:02 -0700 | [diff] [blame] | 974 | depends on MEMCG && SWAP |
KAMEZAWA Hiroyuki | c077719 | 2009-01-07 18:07:57 -0800 | [diff] [blame] | 975 | help |
Johannes Weiner | a0166ec | 2015-12-17 17:19:56 -0500 | [diff] [blame] | 976 | Provides control over the swap space consumed by tasks in a cgroup. |
| 977 | |
Andrew Morton | c255a45 | 2012-07-31 16:43:02 -0700 | [diff] [blame] | 978 | config MEMCG_SWAP_ENABLED |
Johannes Weiner | a0166ec | 2015-12-17 17:19:56 -0500 | [diff] [blame] | 979 | bool "Swap controller enabled by default" |
Andrew Morton | c255a45 | 2012-07-31 16:43:02 -0700 | [diff] [blame] | 980 | depends on MEMCG_SWAP |
Michal Hocko | a42c390 | 2010-11-24 12:57:08 -0800 | [diff] [blame] | 981 | default y |
| 982 | help |
| 983 | Memory Resource Controller Swap Extension comes with its price in |
| 984 | a bigger memory consumption. General purpose distribution kernels |
Jim Cromie | 43d547f | 2010-12-17 14:32:36 -0700 | [diff] [blame] | 985 | which want to enable the feature but keep it disabled by default |
Michal Hocko | 07555ac | 2013-08-22 16:35:46 -0700 | [diff] [blame] | 986 | and let the user enable it by swapaccount=1 boot command line |
Michal Hocko | a42c390 | 2010-11-24 12:57:08 -0800 | [diff] [blame] | 987 | parameter should have this option unselected. |
| 988 | For those who want to have the feature enabled by default should |
| 989 | select this option (if, for some reason, they need to disable it |
WANG Cong | 00a66d2 | 2011-07-25 17:12:12 -0700 | [diff] [blame] | 990 | then swapaccount=0 does the trick). |
KAMEZAWA Hiroyuki | c077719 | 2009-01-07 18:07:57 -0800 | [diff] [blame] | 991 | |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 992 | config BLK_CGROUP |
| 993 | bool "IO controller" |
| 994 | depends on BLOCK |
Aneesh Kumar K.V | 2bc64a2 | 2012-07-31 16:42:12 -0700 | [diff] [blame] | 995 | default n |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 996 | ---help--- |
| 997 | Generic block IO controller cgroup interface. This is the common |
| 998 | cgroup interface which should be used by various IO controlling |
| 999 | policies. |
Aneesh Kumar K.V | 2bc64a2 | 2012-07-31 16:42:12 -0700 | [diff] [blame] | 1000 | |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 1001 | Currently, CFQ IO scheduler uses it to recognize task groups and |
| 1002 | control disk bandwidth allocation (proportional time slice allocation) |
| 1003 | to such task groups. It is also used by bio throttling logic in |
| 1004 | block layer to implement upper limit in IO rates on a device. |
Stephane Eranian | e5d1367 | 2011-02-14 11:20:01 +0200 | [diff] [blame] | 1005 | |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 1006 | This option only enables generic Block IO controller infrastructure. |
| 1007 | One needs to also enable actual IO controlling logic/policy. For |
| 1008 | enabling proportional weight division of disk bandwidth in CFQ, set |
| 1009 | CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set |
| 1010 | CONFIG_BLK_DEV_THROTTLING=y. |
| 1011 | |
| 1012 | See Documentation/cgroups/blkio-controller.txt for more information. |
| 1013 | |
| 1014 | config DEBUG_BLK_CGROUP |
| 1015 | bool "IO controller debugging" |
| 1016 | depends on BLK_CGROUP |
| 1017 | default n |
| 1018 | ---help--- |
| 1019 | Enable some debugging help. Currently it exports additional stat |
| 1020 | files in a cgroup which can be useful for debugging. |
| 1021 | |
| 1022 | config CGROUP_WRITEBACK |
| 1023 | bool |
| 1024 | depends on MEMCG && BLK_CGROUP |
| 1025 | default y |
Stephane Eranian | e5d1367 | 2011-02-14 11:20:01 +0200 | [diff] [blame] | 1026 | |
Dhaval Giani | 7c94143 | 2010-01-20 13:26:18 +0100 | [diff] [blame] | 1027 | menuconfig CGROUP_SCHED |
Johannes Weiner | a0166ec | 2015-12-17 17:19:56 -0500 | [diff] [blame] | 1028 | bool "CPU controller" |
Dhaval Giani | 7c94143 | 2010-01-20 13:26:18 +0100 | [diff] [blame] | 1029 | default n |
| 1030 | help |
| 1031 | This feature lets CPU scheduler recognize task groups and control CPU |
| 1032 | bandwidth allocation to such task groups. It uses cgroups to group |
| 1033 | tasks. |
| 1034 | |
| 1035 | if CGROUP_SCHED |
| 1036 | config FAIR_GROUP_SCHED |
| 1037 | bool "Group scheduling for SCHED_OTHER" |
| 1038 | depends on CGROUP_SCHED |
| 1039 | default CGROUP_SCHED |
| 1040 | |
Paul Turner | ab84d31 | 2011-07-21 09:43:28 -0700 | [diff] [blame] | 1041 | config CFS_BANDWIDTH |
| 1042 | bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED" |
Paul Turner | ab84d31 | 2011-07-21 09:43:28 -0700 | [diff] [blame] | 1043 | depends on FAIR_GROUP_SCHED |
| 1044 | default n |
| 1045 | help |
| 1046 | This option allows users to define CPU bandwidth rates (limits) for |
| 1047 | tasks running within the fair group scheduler. Groups with no limit |
| 1048 | set are considered to be unconstrained and will run with no |
| 1049 | restriction. |
| 1050 | See tip/Documentation/scheduler/sched-bwc.txt for more information. |
| 1051 | |
Dhaval Giani | 7c94143 | 2010-01-20 13:26:18 +0100 | [diff] [blame] | 1052 | config RT_GROUP_SCHED |
| 1053 | bool "Group scheduling for SCHED_RR/FIFO" |
Dhaval Giani | 7c94143 | 2010-01-20 13:26:18 +0100 | [diff] [blame] | 1054 | depends on CGROUP_SCHED |
| 1055 | default n |
| 1056 | help |
| 1057 | This feature lets you explicitly allocate real CPU bandwidth |
Li Zefan | 32bd7eb | 2010-03-24 13:17:19 +0800 | [diff] [blame] | 1058 | to task groups. If enabled, it will also make it impossible to |
Dhaval Giani | 7c94143 | 2010-01-20 13:26:18 +0100 | [diff] [blame] | 1059 | schedule realtime tasks for non-root users until you allocate |
| 1060 | realtime bandwidth for them. |
| 1061 | See Documentation/scheduler/sched-rt-group.txt for more information. |
| 1062 | |
| 1063 | endif #CGROUP_SCHED |
| 1064 | |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 1065 | config CGROUP_PIDS |
| 1066 | bool "PIDs controller" |
| 1067 | help |
| 1068 | Provides enforcement of process number limits in the scope of a |
| 1069 | cgroup. Any attempt to fork more processes than is allowed in the |
| 1070 | cgroup will fail. PIDs are fundamentally a global resource because it |
| 1071 | is fairly trivial to reach PID exhaustion before you reach even a |
| 1072 | conservative kmemcg limit. As a result, it is possible to grind a |
| 1073 | system to halt without being limited by other cgroup policies. The |
Parav Pandit | 6cc578d | 2016-03-05 11:30:56 +0530 | [diff] [blame] | 1074 | PIDs controller is designed to stop this from happening. |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 1075 | |
| 1076 | It should be noted that organisational operations (such as attaching |
Parav Pandit | 6cc578d | 2016-03-05 11:30:56 +0530 | [diff] [blame] | 1077 | to a cgroup hierarchy will *not* be blocked by the PIDs controller), |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 1078 | since the PIDs limit only affects a process's ability to fork, not to |
| 1079 | attach to a cgroup. |
| 1080 | |
| 1081 | config CGROUP_FREEZER |
| 1082 | bool "Freezer controller" |
| 1083 | help |
| 1084 | Provides a way to freeze and unfreeze all tasks in a |
| 1085 | cgroup. |
| 1086 | |
Johannes Weiner | 489c2a2 | 2016-01-20 15:02:41 -0800 | [diff] [blame] | 1087 | This option affects the ORIGINAL cgroup interface. The cgroup2 memory |
| 1088 | controller includes important in-kernel memory consumers per default. |
| 1089 | |
| 1090 | If you're using cgroup2, say N. |
| 1091 | |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 1092 | config CGROUP_HUGETLB |
| 1093 | bool "HugeTLB controller" |
| 1094 | depends on HUGETLB_PAGE |
| 1095 | select PAGE_COUNTER |
Vivek Goyal | afc24d4 | 2010-04-26 19:27:56 +0200 | [diff] [blame] | 1096 | default n |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 1097 | help |
| 1098 | Provides a cgroup controller for HugeTLB pages. |
| 1099 | When you enable this, you can put a per cgroup limit on HugeTLB usage. |
| 1100 | The limit is enforced during page fault. Since HugeTLB doesn't |
| 1101 | support page reclaim, enforcing the limit at page fault time implies |
| 1102 | that, the application will get SIGBUS signal if it tries to access |
| 1103 | HugeTLB pages beyond its limit. This requires the application to know |
| 1104 | beforehand how much HugeTLB pages it would require for its use. The |
| 1105 | control group is tracked in the third page lru pointer. This means |
| 1106 | that we cannot use the controller with huge page less than 3 pages. |
Vivek Goyal | afc24d4 | 2010-04-26 19:27:56 +0200 | [diff] [blame] | 1107 | |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 1108 | config CPUSETS |
| 1109 | bool "Cpuset controller" |
| 1110 | help |
| 1111 | This option will let you create and manage CPUSETs which |
| 1112 | allow dynamically partitioning a system into sets of CPUs and |
| 1113 | Memory Nodes and assigning tasks to run only within those sets. |
| 1114 | This is primarily useful on large SMP or NUMA systems. |
Vivek Goyal | afc24d4 | 2010-04-26 19:27:56 +0200 | [diff] [blame] | 1115 | |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 1116 | Say N if unsure. |
Vivek Goyal | afc24d4 | 2010-04-26 19:27:56 +0200 | [diff] [blame] | 1117 | |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 1118 | config PROC_PID_CPUSET |
| 1119 | bool "Include legacy /proc/<pid>/cpuset file" |
| 1120 | depends on CPUSETS |
Tejun Heo | 89e9b9e | 2015-05-22 17:13:36 -0400 | [diff] [blame] | 1121 | default y |
| 1122 | |
Johannes Weiner | 6bf024e | 2015-12-17 17:19:57 -0500 | [diff] [blame] | 1123 | config CGROUP_DEVICE |
| 1124 | bool "Device controller" |
| 1125 | help |
| 1126 | Provides a cgroup controller implementing whitelists for |
| 1127 | devices which a process in the cgroup can mknod or open. |
| 1128 | |
| 1129 | config CGROUP_CPUACCT |
| 1130 | bool "Simple CPU accounting controller" |
| 1131 | help |
| 1132 | Provides a simple controller for monitoring the |
| 1133 | total CPU consumed by the tasks in a cgroup. |
| 1134 | |
| 1135 | config CGROUP_PERF |
| 1136 | bool "Perf controller" |
| 1137 | depends on PERF_EVENTS |
| 1138 | help |
| 1139 | This option extends the perf per-cpu mode to restrict monitoring |
| 1140 | to threads which belong to the cgroup specified and run on the |
| 1141 | designated cpu. |
| 1142 | |
| 1143 | Say N if unsure. |
| 1144 | |
| 1145 | config CGROUP_DEBUG |
| 1146 | bool "Example controller" |
| 1147 | default n |
| 1148 | help |
| 1149 | This option enables a simple controller that exports |
| 1150 | debugging information about the cgroups framework. |
| 1151 | |
| 1152 | Say N. |
| 1153 | |
Li Zefan | 23964d2 | 2009-01-15 13:50:58 -0800 | [diff] [blame] | 1154 | endif # CGROUPS |
KAMEZAWA Hiroyuki | c077719 | 2009-01-07 18:07:57 -0800 | [diff] [blame] | 1155 | |
Cyrill Gorcunov | 067bce1 | 2012-01-12 17:20:49 -0800 | [diff] [blame] | 1156 | config CHECKPOINT_RESTORE |
| 1157 | bool "Checkpoint/restore support" if EXPERT |
Iago López Galeiras | 2e13ba5 | 2015-06-25 15:00:57 -0700 | [diff] [blame] | 1158 | select PROC_CHILDREN |
Cyrill Gorcunov | 067bce1 | 2012-01-12 17:20:49 -0800 | [diff] [blame] | 1159 | default n |
| 1160 | help |
| 1161 | Enables additional kernel features in a sake of checkpoint/restore. |
| 1162 | In particular it adds auxiliary prctl codes to setup process text, |
| 1163 | data and heap segment sizes, and a few additional /proc filesystem |
| 1164 | entries. |
| 1165 | |
| 1166 | If unsure, say N here. |
| 1167 | |
Daniel Lezcano | 8dd2a82 | 2010-10-27 15:34:38 -0700 | [diff] [blame] | 1168 | menuconfig NAMESPACES |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1169 | bool "Namespaces support" if EXPERT |
Iulia Manda | 2813893 | 2015-04-15 16:16:41 -0700 | [diff] [blame] | 1170 | depends on MULTIUSER |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1171 | default !EXPERT |
Pavel Emelyanov | c5289a6 | 2008-02-08 04:18:19 -0800 | [diff] [blame] | 1172 | help |
| 1173 | Provides the way to make tasks work with different objects using |
| 1174 | the same id. For example same IPC id may refer to different objects |
| 1175 | or same user id or pid may refer to different tasks when used in |
| 1176 | different namespaces. |
| 1177 | |
Daniel Lezcano | 8dd2a82 | 2010-10-27 15:34:38 -0700 | [diff] [blame] | 1178 | if NAMESPACES |
| 1179 | |
Pavel Emelyanov | 58bfdd6d | 2008-02-08 04:18:21 -0800 | [diff] [blame] | 1180 | config UTS_NS |
| 1181 | bool "UTS namespace" |
Daniel Lezcano | 17a6d44 | 2010-10-27 15:34:37 -0700 | [diff] [blame] | 1182 | default y |
Pavel Emelyanov | 58bfdd6d | 2008-02-08 04:18:21 -0800 | [diff] [blame] | 1183 | help |
| 1184 | In this namespace tasks see different info provided with the |
| 1185 | uname() system call |
| 1186 | |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 1187 | config IPC_NS |
| 1188 | bool "IPC namespace" |
Daniel Lezcano | 8dd2a82 | 2010-10-27 15:34:38 -0700 | [diff] [blame] | 1189 | depends on (SYSVIPC || POSIX_MQUEUE) |
Daniel Lezcano | 17a6d44 | 2010-10-27 15:34:37 -0700 | [diff] [blame] | 1190 | default y |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 1191 | help |
| 1192 | In this namespace tasks work with IPC ids which correspond to |
Serge E. Hallyn | 614b84c | 2009-04-06 19:01:08 -0700 | [diff] [blame] | 1193 | different IPC objects in different namespaces. |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 1194 | |
Pavel Emelyanov | aee16ce | 2008-02-08 04:18:23 -0800 | [diff] [blame] | 1195 | config USER_NS |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 1196 | bool "User namespace" |
Eric W. Biederman | 5673a94 | 2011-11-17 10:23:55 -0800 | [diff] [blame] | 1197 | default n |
Pavel Emelyanov | aee16ce | 2008-02-08 04:18:23 -0800 | [diff] [blame] | 1198 | help |
| 1199 | This allows containers, i.e. vservers, to use user namespaces |
| 1200 | to provide different user info for different servers. |
Eric W. Biederman | e11f0ae | 2013-01-25 16:48:31 -0800 | [diff] [blame] | 1201 | |
| 1202 | When user namespaces are enabled in the kernel it is |
Johannes Weiner | d886f4e | 2016-01-20 15:02:47 -0800 | [diff] [blame] | 1203 | recommended that the MEMCG option also be enabled and that |
| 1204 | user-space use the memory control groups to limit the amount |
| 1205 | of memory a memory unprivileged users can use. |
Eric W. Biederman | e11f0ae | 2013-01-25 16:48:31 -0800 | [diff] [blame] | 1206 | |
Pavel Emelyanov | aee16ce | 2008-02-08 04:18:23 -0800 | [diff] [blame] | 1207 | If unsure, say N. |
| 1208 | |
Pavel Emelyanov | 74bd59b | 2008-02-08 04:18:24 -0800 | [diff] [blame] | 1209 | config PID_NS |
Daniel Lezcano | 9bd38c2 | 2010-10-27 15:34:37 -0700 | [diff] [blame] | 1210 | bool "PID Namespaces" |
Daniel Lezcano | 17a6d44 | 2010-10-27 15:34:37 -0700 | [diff] [blame] | 1211 | default y |
Pavel Emelyanov | 74bd59b | 2008-02-08 04:18:24 -0800 | [diff] [blame] | 1212 | help |
Heikki Orsila | 12d2b8f | 2008-07-06 15:48:02 +0300 | [diff] [blame] | 1213 | Support process id namespaces. This allows having multiple |
Matt LaPlante | 692105b | 2009-01-26 11:12:25 +0100 | [diff] [blame] | 1214 | processes with the same pid as long as they are in different |
Pavel Emelyanov | 74bd59b | 2008-02-08 04:18:24 -0800 | [diff] [blame] | 1215 | pid namespaces. This is a building block of containers. |
| 1216 | |
Matt Helsley | d6eb633 | 2009-01-26 12:25:55 -0800 | [diff] [blame] | 1217 | config NET_NS |
| 1218 | bool "Network namespace" |
Daniel Lezcano | 8dd2a82 | 2010-10-27 15:34:38 -0700 | [diff] [blame] | 1219 | depends on NET |
Daniel Lezcano | 17a6d44 | 2010-10-27 15:34:37 -0700 | [diff] [blame] | 1220 | default y |
Matt Helsley | d6eb633 | 2009-01-26 12:25:55 -0800 | [diff] [blame] | 1221 | help |
| 1222 | Allow user space to create what appear to be multiple instances |
| 1223 | of the network stack. |
| 1224 | |
Daniel Lezcano | 8dd2a82 | 2010-10-27 15:34:38 -0700 | [diff] [blame] | 1225 | endif # NAMESPACES |
| 1226 | |
Mike Galbraith | 5091faa | 2010-11-30 14:18:03 +0100 | [diff] [blame] | 1227 | config SCHED_AUTOGROUP |
| 1228 | bool "Automatic process group scheduling" |
Mike Galbraith | 5091faa | 2010-11-30 14:18:03 +0100 | [diff] [blame] | 1229 | select CGROUPS |
| 1230 | select CGROUP_SCHED |
| 1231 | select FAIR_GROUP_SCHED |
| 1232 | help |
| 1233 | This option optimizes the scheduler for common desktop workloads by |
| 1234 | automatically creating and populating task groups. This separation |
| 1235 | of workloads isolates aggressive CPU burners (like build jobs) from |
| 1236 | desktop applications. Task group autogeneration is currently based |
| 1237 | upon task session. |
| 1238 | |
Daniel Lezcano | 7af37be | 2010-10-27 15:34:41 -0700 | [diff] [blame] | 1239 | config SYSFS_DEPRECATED |
Ferenc Wagner | 5d6a4ea | 2011-01-10 19:04:22 +0100 | [diff] [blame] | 1240 | bool "Enable deprecated sysfs features to support old userspace tools" |
Daniel Lezcano | 7af37be | 2010-10-27 15:34:41 -0700 | [diff] [blame] | 1241 | depends on SYSFS |
| 1242 | default n |
| 1243 | help |
| 1244 | This option adds code that switches the layout of the "block" class |
| 1245 | devices, to not show up in /sys/class/block/, but only in |
| 1246 | /sys/block/. |
| 1247 | |
| 1248 | This switch is only active when the sysfs.deprecated=1 boot option is |
| 1249 | passed or the SYSFS_DEPRECATED_V2 option is set. |
| 1250 | |
| 1251 | This option allows new kernels to run on old distributions and tools, |
| 1252 | which might get confused by /sys/class/block/. Since 2007/2008 all |
| 1253 | major distributions and tools handle this just fine. |
| 1254 | |
| 1255 | Recent distributions and userspace tools after 2009/2010 depend on |
| 1256 | the existence of /sys/class/block/, and will not work with this |
| 1257 | option enabled. |
| 1258 | |
| 1259 | Only if you are using a new kernel on an old distribution, you might |
| 1260 | need to say Y here. |
| 1261 | |
| 1262 | config SYSFS_DEPRECATED_V2 |
Ferenc Wagner | 5d6a4ea | 2011-01-10 19:04:22 +0100 | [diff] [blame] | 1263 | bool "Enable deprecated sysfs features by default" |
Daniel Lezcano | 7af37be | 2010-10-27 15:34:41 -0700 | [diff] [blame] | 1264 | default n |
| 1265 | depends on SYSFS |
| 1266 | depends on SYSFS_DEPRECATED |
| 1267 | help |
| 1268 | Enable deprecated sysfs by default. |
| 1269 | |
| 1270 | See the CONFIG_SYSFS_DEPRECATED option for more details about this |
| 1271 | option. |
| 1272 | |
| 1273 | Only if you are using a new kernel on an old distribution, you might |
| 1274 | need to say Y here. Even then, odds are you would not need it |
| 1275 | enabled, you can always pass the boot option if absolutely necessary. |
| 1276 | |
| 1277 | config RELAY |
| 1278 | bool "Kernel->user space relay support (formerly relayfs)" |
| 1279 | help |
| 1280 | This option enables support for relay interface support in |
| 1281 | certain file systems (such as debugfs). |
| 1282 | It is designed to provide an efficient mechanism for tools and |
| 1283 | facilities to relay large amounts of data from kernel space to |
| 1284 | user space. |
| 1285 | |
| 1286 | If unsure, say N. |
| 1287 | |
Dimitri Gorokhovik | f991633 | 2007-03-06 01:42:17 -0800 | [diff] [blame] | 1288 | config BLK_DEV_INITRD |
| 1289 | bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support" |
| 1290 | depends on BROKEN || !FRV |
| 1291 | help |
| 1292 | The initial RAM filesystem is a ramfs which is loaded by the |
| 1293 | boot loader (loadlin or lilo) and that is mounted as root |
| 1294 | before the normal boot procedure. It is typically used to |
| 1295 | load modules needed to mount the "real" root file system, |
| 1296 | etc. See <file:Documentation/initrd.txt> for details. |
| 1297 | |
| 1298 | If RAM disk support (BLK_DEV_RAM) is also included, this |
| 1299 | also enables initial RAM disk (initrd) support and adds |
| 1300 | 15 Kbytes (more on some other architectures) to the kernel size. |
| 1301 | |
| 1302 | If unsure say Y. |
| 1303 | |
Jean-Paul Saman | c33df4e | 2007-02-10 01:44:43 -0800 | [diff] [blame] | 1304 | if BLK_DEV_INITRD |
| 1305 | |
Sam Ravnborg | dbec486 | 2005-08-10 20:44:50 +0200 | [diff] [blame] | 1306 | source "usr/Kconfig" |
| 1307 | |
Jean-Paul Saman | c33df4e | 2007-02-10 01:44:43 -0800 | [diff] [blame] | 1308 | endif |
| 1309 | |
Arnd Bergmann | 877417e | 2016-04-25 17:35:27 +0200 | [diff] [blame] | 1310 | choice |
| 1311 | prompt "Compiler optimization level" |
| 1312 | default CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE |
| 1313 | |
| 1314 | config CC_OPTIMIZE_FOR_PERFORMANCE |
| 1315 | bool "Optimize for performance" |
| 1316 | help |
| 1317 | This is the default optimization level for the kernel, building |
| 1318 | with the "-O2" compiler flag for best performance and most |
| 1319 | helpful compile-time warnings. |
| 1320 | |
Linus Torvalds | c45b4f1 | 2005-12-14 18:52:21 -0800 | [diff] [blame] | 1321 | config CC_OPTIMIZE_FOR_SIZE |
Ingo Molnar | 96fffeb | 2008-04-28 01:39:43 +0200 | [diff] [blame] | 1322 | bool "Optimize for size" |
Linus Torvalds | c45b4f1 | 2005-12-14 18:52:21 -0800 | [diff] [blame] | 1323 | help |
Masahiro Yamada | 31a4af7 | 2014-08-05 14:43:07 +0900 | [diff] [blame] | 1324 | Enabling this option will pass "-Os" instead of "-O2" to |
| 1325 | your compiler resulting in a smaller kernel. |
Linus Torvalds | c45b4f1 | 2005-12-14 18:52:21 -0800 | [diff] [blame] | 1326 | |
Kirill Smelkov | 3a55fb0 | 2012-11-02 15:41:01 +0400 | [diff] [blame] | 1327 | If unsure, say N. |
Linus Torvalds | c45b4f1 | 2005-12-14 18:52:21 -0800 | [diff] [blame] | 1328 | |
Arnd Bergmann | 877417e | 2016-04-25 17:35:27 +0200 | [diff] [blame] | 1329 | endchoice |
| 1330 | |
Randy Dunlap | 0847062 | 2006-09-30 23:28:13 -0700 | [diff] [blame] | 1331 | config SYSCTL |
| 1332 | bool |
| 1333 | |
Randy Dunlap | b943c46 | 2009-03-10 12:55:46 -0700 | [diff] [blame] | 1334 | config ANON_INODES |
| 1335 | bool |
| 1336 | |
Mike Frysinger | 657a520 | 2013-04-30 15:28:45 -0700 | [diff] [blame] | 1337 | config HAVE_UID16 |
| 1338 | bool |
| 1339 | |
| 1340 | config SYSCTL_EXCEPTION_TRACE |
| 1341 | bool |
| 1342 | help |
| 1343 | Enable support for /proc/sys/debug/exception-trace. |
| 1344 | |
| 1345 | config SYSCTL_ARCH_UNALIGN_NO_WARN |
| 1346 | bool |
| 1347 | help |
| 1348 | Enable support for /proc/sys/kernel/ignore-unaligned-usertrap |
| 1349 | Allows arch to define/use @no_unaligned_warning to possibly warn |
| 1350 | about unaligned access emulation going on under the hood. |
| 1351 | |
| 1352 | config SYSCTL_ARCH_UNALIGN_ALLOW |
| 1353 | bool |
| 1354 | help |
| 1355 | Enable support for /proc/sys/kernel/unaligned-trap |
| 1356 | Allows arches to define/use @unaligned_enabled to runtime toggle |
| 1357 | the unaligned access emulation. |
| 1358 | see arch/parisc/kernel/unaligned.c for reference |
| 1359 | |
Mike Frysinger | 657a520 | 2013-04-30 15:28:45 -0700 | [diff] [blame] | 1360 | config HAVE_PCSPKR_PLATFORM |
| 1361 | bool |
| 1362 | |
Alexei Starovoitov | f89b775 | 2014-10-23 18:41:08 -0700 | [diff] [blame] | 1363 | # interpreter that classic socket filters depend on |
| 1364 | config BPF |
| 1365 | bool |
| 1366 | |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1367 | menuconfig EXPERT |
| 1368 | bool "Configure standard kernel features (expert users)" |
Josh Triplett | f505c55 | 2011-06-05 18:23:58 -0700 | [diff] [blame] | 1369 | # Unhide debug options, to make the on-by-default options visible |
| 1370 | select DEBUG_KERNEL |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1371 | help |
| 1372 | This option allows certain base kernel options and settings |
| 1373 | to be disabled or tweaked. This is for specialized |
| 1374 | environments which can tolerate a "non-standard" kernel. |
| 1375 | Only use this if you really know what you are doing. |
| 1376 | |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 1377 | config UID16 |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1378 | bool "Enable 16-bit UID system calls" if EXPERT |
Iulia Manda | 2813893 | 2015-04-15 16:16:41 -0700 | [diff] [blame] | 1379 | depends on HAVE_UID16 && MULTIUSER |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 1380 | default y |
| 1381 | help |
| 1382 | This enables the legacy 16-bit UID syscall wrappers. |
| 1383 | |
Iulia Manda | 2813893 | 2015-04-15 16:16:41 -0700 | [diff] [blame] | 1384 | config MULTIUSER |
| 1385 | bool "Multiple users, groups and capabilities support" if EXPERT |
| 1386 | default y |
| 1387 | help |
| 1388 | This option enables support for non-root users, groups and |
| 1389 | capabilities. |
| 1390 | |
| 1391 | If you say N here, all processes will run with UID 0, GID 0, and all |
| 1392 | possible capabilities. Saying N here also compiles out support for |
| 1393 | system calls related to UIDs, GIDs, and capabilities, such as setuid, |
| 1394 | setgid, and capset. |
| 1395 | |
| 1396 | If unsure, say Y here. |
| 1397 | |
Fabian Frederick | f618776 | 2014-06-04 16:11:12 -0700 | [diff] [blame] | 1398 | config SGETMASK_SYSCALL |
| 1399 | bool "sgetmask/ssetmask syscalls support" if EXPERT |
| 1400 | def_bool PARISC || MN10300 || BLACKFIN || M68K || PPC || MIPS || X86 || SPARC || CRIS || MICROBLAZE || SUPERH |
| 1401 | ---help--- |
| 1402 | sys_sgetmask and sys_ssetmask are obsolete system calls |
| 1403 | no longer supported in libc but still enabled by default in some |
| 1404 | architectures. |
| 1405 | |
| 1406 | If unsure, leave the default option here. |
| 1407 | |
Fabian Frederick | 6af9f7b | 2014-04-03 14:48:25 -0700 | [diff] [blame] | 1408 | config SYSFS_SYSCALL |
| 1409 | bool "Sysfs syscall support" if EXPERT |
| 1410 | default y |
| 1411 | ---help--- |
| 1412 | sys_sysfs is an obsolete system call no longer supported in libc. |
| 1413 | Note that disabling this option is more secure but might break |
| 1414 | compatibility with some systems. |
| 1415 | |
| 1416 | If unsure say Y here. |
| 1417 | |
Eric W. Biederman | b89a817 | 2006-09-27 01:51:04 -0700 | [diff] [blame] | 1418 | config SYSCTL_SYSCALL |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1419 | bool "Sysctl syscall support" if EXPERT |
Eric W. Biederman | 26a7034 | 2009-11-05 05:26:41 -0800 | [diff] [blame] | 1420 | depends on PROC_SYSCTL |
WANG Cong | c736de6 | 2011-11-02 13:39:25 -0700 | [diff] [blame] | 1421 | default n |
Eric W. Biederman | b89a817 | 2006-09-27 01:51:04 -0700 | [diff] [blame] | 1422 | select SYSCTL |
| 1423 | ---help--- |
Eric W. Biederman | 13bb7e3 | 2006-11-08 17:44:51 -0800 | [diff] [blame] | 1424 | sys_sysctl uses binary paths that have been found challenging |
| 1425 | to properly maintain and use. The interface in /proc/sys |
| 1426 | using paths with ascii names is now the primary path to this |
| 1427 | information. |
Eric W. Biederman | b89a817 | 2006-09-27 01:51:04 -0700 | [diff] [blame] | 1428 | |
Eric W. Biederman | 13bb7e3 | 2006-11-08 17:44:51 -0800 | [diff] [blame] | 1429 | Almost nothing using the binary sysctl interface so if you are |
| 1430 | trying to save some space it is probably safe to disable this, |
| 1431 | making your kernel marginally smaller. |
Eric W. Biederman | b89a817 | 2006-09-27 01:51:04 -0700 | [diff] [blame] | 1432 | |
WANG Cong | c736de6 | 2011-11-02 13:39:25 -0700 | [diff] [blame] | 1433 | If unsure say N here. |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 1434 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1435 | config KALLSYMS |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1436 | bool "Load all symbols for debugging/ksymoops" if EXPERT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1437 | default y |
| 1438 | help |
| 1439 | Say Y here to let the kernel print out symbolic crash information and |
| 1440 | symbolic stack backtraces. This increases the size of the kernel |
| 1441 | somewhat, as all symbols have to be loaded into the kernel image. |
| 1442 | |
| 1443 | config KALLSYMS_ALL |
| 1444 | bool "Include all symbols in kallsyms" |
| 1445 | depends on DEBUG_KERNEL && KALLSYMS |
| 1446 | help |
Artem Bityutskiy | 71a83ec | 2011-04-05 13:24:57 +0300 | [diff] [blame] | 1447 | Normally kallsyms only contains the symbols of functions for nicer |
| 1448 | OOPS messages and backtraces (i.e., symbols from the text and inittext |
| 1449 | sections). This is sufficient for most cases. And only in very rare |
| 1450 | cases (e.g., when a debugger is used) all symbols are required (e.g., |
| 1451 | names of variables from the data sections, etc). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1452 | |
Artem Bityutskiy | 71a83ec | 2011-04-05 13:24:57 +0300 | [diff] [blame] | 1453 | This option makes sure that all symbols are loaded into the kernel |
| 1454 | image (i.e., symbols from all sections) in cost of increased kernel |
| 1455 | size (depending on the kernel configuration, it may be 300KiB or |
| 1456 | something like this). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1457 | |
Artem Bityutskiy | 71a83ec | 2011-04-05 13:24:57 +0300 | [diff] [blame] | 1458 | Say N unless you really need all symbols. |
Matt Mackall | d59745c | 2005-05-01 08:59:02 -0700 | [diff] [blame] | 1459 | |
Ard Biesheuvel | 4d5d566 | 2016-03-15 14:58:12 -0700 | [diff] [blame] | 1460 | config KALLSYMS_ABSOLUTE_PERCPU |
| 1461 | bool |
| 1462 | default X86_64 && SMP |
| 1463 | |
Ard Biesheuvel | 2213e9a | 2016-03-15 14:58:19 -0700 | [diff] [blame] | 1464 | config KALLSYMS_BASE_RELATIVE |
| 1465 | bool |
| 1466 | depends on KALLSYMS |
| 1467 | default !IA64 && !(TILE && 64BIT) |
| 1468 | help |
| 1469 | Instead of emitting them as absolute values in the native word size, |
| 1470 | emit the symbol references in the kallsyms table as 32-bit entries, |
| 1471 | each containing a relative value in the range [base, base + U32_MAX] |
| 1472 | or, when KALLSYMS_ABSOLUTE_PERCPU is in effect, each containing either |
| 1473 | an absolute value in the range [0, S32_MAX] or a relative value in the |
| 1474 | range [base, base + S32_MAX], where base is the lowest relative symbol |
| 1475 | address encountered in the image. |
| 1476 | |
| 1477 | On 64-bit builds, this reduces the size of the address table by 50%, |
| 1478 | but more importantly, it results in entries whose values are build |
| 1479 | time constants, and no relocation pass is required at runtime to fix |
| 1480 | up the entries based on the runtime load address of the kernel. |
| 1481 | |
Matt Mackall | d59745c | 2005-05-01 08:59:02 -0700 | [diff] [blame] | 1482 | config PRINTK |
| 1483 | default y |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1484 | bool "Enable support for printk" if EXPERT |
Frederic Weisbecker | 74876a9 | 2012-10-12 18:00:23 +0200 | [diff] [blame] | 1485 | select IRQ_WORK |
Matt Mackall | d59745c | 2005-05-01 08:59:02 -0700 | [diff] [blame] | 1486 | help |
| 1487 | This option enables normal printk support. Removing it |
| 1488 | eliminates most of the message strings from the kernel image |
| 1489 | and makes the kernel more or less silent. As this makes it |
| 1490 | very difficult to diagnose system problems, saying N here is |
| 1491 | strongly discouraged. |
| 1492 | |
Petr Mladek | 42a0bb3 | 2016-05-20 17:00:33 -0700 | [diff] [blame] | 1493 | config PRINTK_NMI |
| 1494 | def_bool y |
| 1495 | depends on PRINTK |
| 1496 | depends on HAVE_NMI |
| 1497 | |
Matt Mackall | c8538a7 | 2005-05-01 08:59:01 -0700 | [diff] [blame] | 1498 | config BUG |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1499 | bool "BUG() support" if EXPERT |
Matt Mackall | c8538a7 | 2005-05-01 08:59:01 -0700 | [diff] [blame] | 1500 | default y |
| 1501 | help |
| 1502 | Disabling this option eliminates support for BUG and WARN, reducing |
| 1503 | the size of your kernel image and potentially quietly ignoring |
| 1504 | numerous fatal conditions. You should only consider disabling this |
| 1505 | option for embedded systems with no facilities for reporting errors. |
| 1506 | Just say Y. |
| 1507 | |
Matt Mackall | 708e9a7 | 2006-01-08 01:05:25 -0800 | [diff] [blame] | 1508 | config ELF_CORE |
Alex Kelly | 046d662 | 2012-10-04 17:15:23 -0700 | [diff] [blame] | 1509 | depends on COREDUMP |
Matt Mackall | 708e9a7 | 2006-01-08 01:05:25 -0800 | [diff] [blame] | 1510 | default y |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1511 | bool "Enable ELF core dumps" if EXPERT |
Matt Mackall | 708e9a7 | 2006-01-08 01:05:25 -0800 | [diff] [blame] | 1512 | help |
| 1513 | Enable support for generating core dumps. Disabling saves about 4k. |
| 1514 | |
Ralf Baechle | 8761f1a | 2011-06-01 19:05:09 +0100 | [diff] [blame] | 1515 | |
Stas Sergeev | e5e1d3c | 2008-05-07 12:39:56 +0200 | [diff] [blame] | 1516 | config PCSPKR_PLATFORM |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1517 | bool "Enable PC-Speaker support" if EXPERT |
Ralf Baechle | 8761f1a | 2011-06-01 19:05:09 +0100 | [diff] [blame] | 1518 | depends on HAVE_PCSPKR_PLATFORM |
Ralf Baechle | 15f304b | 2011-06-01 19:04:59 +0100 | [diff] [blame] | 1519 | select I8253_LOCK |
Stas Sergeev | e5e1d3c | 2008-05-07 12:39:56 +0200 | [diff] [blame] | 1520 | default y |
| 1521 | help |
| 1522 | This option allows to disable the internal PC-Speaker |
| 1523 | support, saving some memory. |
| 1524 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1525 | config BASE_FULL |
| 1526 | default y |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1527 | bool "Enable full-sized data structures for core" if EXPERT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1528 | help |
| 1529 | Disabling this option reduces the size of miscellaneous core |
| 1530 | kernel data structures. This saves memory on small machines, |
| 1531 | but may reduce performance. |
| 1532 | |
| 1533 | config FUTEX |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1534 | bool "Enable futex support" if EXPERT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1535 | default y |
Ingo Molnar | 23f78d4a | 2006-06-27 02:54:53 -0700 | [diff] [blame] | 1536 | select RT_MUTEXES |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1537 | help |
| 1538 | Disabling this option will cause the kernel to be built without |
| 1539 | support for "fast userspace mutexes". The resulting kernel may not |
| 1540 | run glibc-based applications correctly. |
| 1541 | |
Heiko Carstens | 03b8c7b | 2014-03-02 13:09:47 +0100 | [diff] [blame] | 1542 | config HAVE_FUTEX_CMPXCHG |
| 1543 | bool |
Josh Triplett | 62b4d20 | 2014-10-03 16:19:24 -0700 | [diff] [blame] | 1544 | depends on FUTEX |
Heiko Carstens | 03b8c7b | 2014-03-02 13:09:47 +0100 | [diff] [blame] | 1545 | help |
| 1546 | Architectures should select this if futex_atomic_cmpxchg_inatomic() |
| 1547 | is implemented and always working. This removes a couple of runtime |
| 1548 | checks. |
| 1549 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1550 | config EPOLL |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1551 | bool "Enable eventpoll support" if EXPERT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1552 | default y |
Adrian Bunk | 448e3ce | 2007-07-31 00:39:10 -0700 | [diff] [blame] | 1553 | select ANON_INODES |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1554 | help |
| 1555 | Disabling this option will cause the kernel to be built without |
| 1556 | support for epoll family of system calls. |
| 1557 | |
Davide Libenzi | fba2afa | 2007-05-10 22:23:13 -0700 | [diff] [blame] | 1558 | config SIGNALFD |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1559 | bool "Enable signalfd() system call" if EXPERT |
Adrian Bunk | 448e3ce | 2007-07-31 00:39:10 -0700 | [diff] [blame] | 1560 | select ANON_INODES |
Davide Libenzi | fba2afa | 2007-05-10 22:23:13 -0700 | [diff] [blame] | 1561 | default y |
| 1562 | help |
| 1563 | Enable the signalfd() system call that allows to receive signals |
| 1564 | on a file descriptor. |
| 1565 | |
| 1566 | If unsure, say Y. |
| 1567 | |
Davide Libenzi | b215e28 | 2007-05-10 22:23:16 -0700 | [diff] [blame] | 1568 | config TIMERFD |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1569 | bool "Enable timerfd() system call" if EXPERT |
Adrian Bunk | 448e3ce | 2007-07-31 00:39:10 -0700 | [diff] [blame] | 1570 | select ANON_INODES |
Davide Libenzi | b215e28 | 2007-05-10 22:23:16 -0700 | [diff] [blame] | 1571 | default y |
| 1572 | help |
| 1573 | Enable the timerfd() system call that allows to receive timer |
| 1574 | events on a file descriptor. |
| 1575 | |
| 1576 | If unsure, say Y. |
| 1577 | |
Davide Libenzi | e1ad746 | 2007-05-10 22:23:19 -0700 | [diff] [blame] | 1578 | config EVENTFD |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1579 | bool "Enable eventfd() system call" if EXPERT |
Adrian Bunk | 448e3ce | 2007-07-31 00:39:10 -0700 | [diff] [blame] | 1580 | select ANON_INODES |
Davide Libenzi | e1ad746 | 2007-05-10 22:23:19 -0700 | [diff] [blame] | 1581 | default y |
| 1582 | help |
| 1583 | Enable the eventfd() system call that allows to receive both |
| 1584 | kernel notification (ie. KAIO) or userspace notifications. |
| 1585 | |
| 1586 | If unsure, say Y. |
| 1587 | |
Alexei Starovoitov | f89b775 | 2014-10-23 18:41:08 -0700 | [diff] [blame] | 1588 | # syscall, maps, verifier |
| 1589 | config BPF_SYSCALL |
Ingo Molnar | e1abf2c | 2015-04-02 15:51:39 +0200 | [diff] [blame] | 1590 | bool "Enable bpf() system call" |
Alexei Starovoitov | f89b775 | 2014-10-23 18:41:08 -0700 | [diff] [blame] | 1591 | select ANON_INODES |
| 1592 | select BPF |
| 1593 | default n |
| 1594 | help |
| 1595 | Enable the bpf() system call that allows to manipulate eBPF |
| 1596 | programs and maps via file descriptors. |
| 1597 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1598 | config SHMEM |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1599 | bool "Use full shmem filesystem" if EXPERT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1600 | default y |
| 1601 | depends on MMU |
| 1602 | help |
| 1603 | The shmem is an internal filesystem used to manage shared memory. |
| 1604 | It is backed by swap and manages resource limits. It is also exported |
| 1605 | to userspace as tmpfs if TMPFS is enabled. Disabling this |
| 1606 | option replaces shmem and tmpfs with the much simpler ramfs code, |
| 1607 | which may be appropriate on small systems without swap. |
| 1608 | |
Thomas Petazzoni | ebf3f09 | 2008-10-15 22:05:12 -0700 | [diff] [blame] | 1609 | config AIO |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1610 | bool "Enable AIO support" if EXPERT |
Thomas Petazzoni | ebf3f09 | 2008-10-15 22:05:12 -0700 | [diff] [blame] | 1611 | default y |
| 1612 | help |
| 1613 | This option enables POSIX asynchronous I/O which may by used |
Mike Frysinger | 657a520 | 2013-04-30 15:28:45 -0700 | [diff] [blame] | 1614 | by some high performance threaded applications. Disabling |
| 1615 | this option saves about 7k. |
| 1616 | |
Josh Triplett | d3ac21c | 2014-08-17 19:41:09 -0500 | [diff] [blame] | 1617 | config ADVISE_SYSCALLS |
| 1618 | bool "Enable madvise/fadvise syscalls" if EXPERT |
| 1619 | default y |
| 1620 | help |
| 1621 | This option enables the madvise and fadvise syscalls, used by |
| 1622 | applications to advise the kernel about their future memory or file |
| 1623 | usage, improving performance. If building an embedded system where no |
| 1624 | applications use these syscalls, you can disable this option to save |
| 1625 | space. |
| 1626 | |
Andrea Arcangeli | a14c151 | 2015-09-04 15:46:54 -0700 | [diff] [blame] | 1627 | config USERFAULTFD |
| 1628 | bool "Enable userfaultfd() system call" |
| 1629 | select ANON_INODES |
Andrea Arcangeli | a14c151 | 2015-09-04 15:46:54 -0700 | [diff] [blame] | 1630 | depends on MMU |
| 1631 | help |
| 1632 | Enable the userfaultfd() system call that allows to intercept and |
| 1633 | handle page faults in userland. |
| 1634 | |
Mike Frysinger | 657a520 | 2013-04-30 15:28:45 -0700 | [diff] [blame] | 1635 | config PCI_QUIRKS |
| 1636 | default y |
| 1637 | bool "Enable PCI quirk workarounds" if EXPERT |
| 1638 | depends on PCI |
| 1639 | help |
| 1640 | This enables workarounds for various PCI chipset |
| 1641 | bugs/quirks. Disable this only if your target machine is |
| 1642 | unaffected by PCI quirks. |
Thomas Petazzoni | ebf3f09 | 2008-10-15 22:05:12 -0700 | [diff] [blame] | 1643 | |
Mathieu Desnoyers | 5b25b13 | 2015-09-11 13:07:39 -0700 | [diff] [blame] | 1644 | config MEMBARRIER |
| 1645 | bool "Enable membarrier() system call" if EXPERT |
| 1646 | default y |
| 1647 | help |
| 1648 | Enable the membarrier() system call that allows issuing memory |
| 1649 | barriers across all running threads, which can be used to distribute |
| 1650 | the cost of user-space memory barriers asymmetrically by transforming |
| 1651 | pairs of memory barriers into pairs consisting of membarrier() and a |
| 1652 | compiler barrier. |
| 1653 | |
| 1654 | If unsure, say Y. |
| 1655 | |
Randy Dunlap | 6befe5f | 2011-04-26 12:33:21 -0700 | [diff] [blame] | 1656 | config EMBEDDED |
| 1657 | bool "Embedded system" |
Josh Triplett | 5d2acfc | 2014-04-07 15:39:09 -0700 | [diff] [blame] | 1658 | option allnoconfig_y |
Randy Dunlap | 6befe5f | 2011-04-26 12:33:21 -0700 | [diff] [blame] | 1659 | select EXPERT |
| 1660 | help |
| 1661 | This option should be enabled if compiling the kernel for |
| 1662 | an embedded system so certain expert options are available |
| 1663 | for configuration. |
| 1664 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1665 | config HAVE_PERF_EVENTS |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1666 | bool |
Mike Frysinger | 018df72 | 2009-06-12 13:17:43 -0400 | [diff] [blame] | 1667 | help |
| 1668 | See tools/perf/design.txt for details. |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1669 | |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 1670 | config PERF_USE_VMALLOC |
| 1671 | bool |
| 1672 | help |
| 1673 | See tools/perf/design.txt for details |
| 1674 | |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1675 | menu "Kernel Performance Events And Counters" |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1676 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1677 | config PERF_EVENTS |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1678 | bool "Kernel performance events and counters" |
Robert Richter | 392d65a | 2012-04-05 18:24:44 +0200 | [diff] [blame] | 1679 | default y if PROFILING |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1680 | depends on HAVE_PERF_EVENTS |
Ingo Molnar | 4c59e46 | 2008-12-08 19:38:33 +0100 | [diff] [blame] | 1681 | select ANON_INODES |
Peter Zijlstra | e360adb | 2010-10-14 14:01:34 +0800 | [diff] [blame] | 1682 | select IRQ_WORK |
Pranith Kumar | 83fe27e | 2014-12-05 11:24:45 -0500 | [diff] [blame] | 1683 | select SRCU |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1684 | help |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1685 | Enable kernel support for various performance events provided |
| 1686 | by software and hardware. |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1687 | |
Thadeu Lima de Souza Cascardo | dd77038 | 2009-10-30 19:32:25 -0200 | [diff] [blame] | 1688 | Software events are supported either built-in or via the |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1689 | use of generic tracepoints. |
| 1690 | |
| 1691 | Most modern CPUs support performance events via performance |
| 1692 | counter registers. These registers count the number of certain |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1693 | types of hw events: such as instructions executed, cachemisses |
| 1694 | suffered, or branches mis-predicted - without slowing down the |
| 1695 | kernel or applications. These registers can also trigger interrupts |
| 1696 | when a threshold number of events have passed - and can thus be |
| 1697 | used to profile the code that runs on that CPU. |
| 1698 | |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1699 | The Linux Performance Event subsystem provides an abstraction of |
Thadeu Lima de Souza Cascardo | dd77038 | 2009-10-30 19:32:25 -0200 | [diff] [blame] | 1700 | these software and hardware event capabilities, available via a |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 1701 | system call and used by the "perf" utility in tools/perf/. It |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1702 | provides per task and per CPU counters, and it provides event |
| 1703 | capabilities on top of those. |
| 1704 | |
| 1705 | Say Y if unsure. |
| 1706 | |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 1707 | config DEBUG_PERF_USE_VMALLOC |
| 1708 | default n |
| 1709 | bool "Debug: use vmalloc to back perf mmap() buffers" |
Michael Ellerman | cb30711 | 2015-05-04 16:26:39 +1000 | [diff] [blame] | 1710 | depends on PERF_EVENTS && DEBUG_KERNEL && !PPC |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 1711 | select PERF_USE_VMALLOC |
| 1712 | help |
| 1713 | Use vmalloc memory to back perf mmap() buffers. |
| 1714 | |
| 1715 | Mostly useful for debugging the vmalloc code on platforms |
| 1716 | that don't require it. |
| 1717 | |
| 1718 | Say N if unsure. |
| 1719 | |
Thomas Gleixner | 0793a61 | 2008-12-04 20:12:29 +0100 | [diff] [blame] | 1720 | endmenu |
| 1721 | |
Christoph Lameter | f8891e5 | 2006-06-30 01:55:45 -0700 | [diff] [blame] | 1722 | config VM_EVENT_COUNTERS |
| 1723 | default y |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1724 | bool "Enable VM event counters for /proc/vmstat" if EXPERT |
Christoph Lameter | f8891e5 | 2006-06-30 01:55:45 -0700 | [diff] [blame] | 1725 | help |
Paul Jackson | 2aea4fb | 2006-12-22 01:06:10 -0800 | [diff] [blame] | 1726 | VM event counters are needed for event counts to be shown. |
| 1727 | This option allows the disabling of the VM event counters |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1728 | on EXPERT systems. /proc/vmstat will only show page counts |
Paul Jackson | 2aea4fb | 2006-12-22 01:06:10 -0800 | [diff] [blame] | 1729 | if VM event counters are disabled. |
Christoph Lameter | f8891e5 | 2006-06-30 01:55:45 -0700 | [diff] [blame] | 1730 | |
Christoph Lameter | 41ecc55 | 2007-05-09 02:32:44 -0700 | [diff] [blame] | 1731 | config SLUB_DEBUG |
| 1732 | default y |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1733 | bool "Enable SLUB debugging support" if EXPERT |
Christoph Lameter | f6acb63 | 2008-04-29 16:16:06 -0700 | [diff] [blame] | 1734 | depends on SLUB && SYSFS |
Christoph Lameter | 41ecc55 | 2007-05-09 02:32:44 -0700 | [diff] [blame] | 1735 | help |
| 1736 | SLUB has extensive debug support features. Disabling these can |
| 1737 | result in significant savings in code size. This also disables |
| 1738 | SLUB sysfs support. /sys/slab will not exist and there will be |
| 1739 | no support for cache validation etc. |
| 1740 | |
Randy Dunlap | b943c46 | 2009-03-10 12:55:46 -0700 | [diff] [blame] | 1741 | config COMPAT_BRK |
| 1742 | bool "Disable heap randomization" |
| 1743 | default y |
| 1744 | help |
| 1745 | Randomizing heap placement makes heap exploits harder, but it |
| 1746 | also breaks ancient binaries (including anything libc5 based). |
| 1747 | This option changes the bootup default to heap randomization |
Matt LaPlante | 692105b | 2009-01-26 11:12:25 +0100 | [diff] [blame] | 1748 | disabled, and can be overridden at runtime by setting |
Randy Dunlap | b943c46 | 2009-03-10 12:55:46 -0700 | [diff] [blame] | 1749 | /proc/sys/kernel/randomize_va_space to 2. |
| 1750 | |
| 1751 | On non-ancient distros (post-2000 ones) N is usually a safe choice. |
| 1752 | |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1753 | choice |
| 1754 | prompt "Choose SLAB allocator" |
Christoph Lameter | a0acd82 | 2007-07-17 04:03:32 -0700 | [diff] [blame] | 1755 | default SLUB |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1756 | help |
| 1757 | This option allows to select a slab allocator. |
| 1758 | |
| 1759 | config SLAB |
| 1760 | bool "SLAB" |
| 1761 | help |
| 1762 | The regular slab allocator that is established and known to work |
Christoph Lameter | 3401388 | 2007-05-09 02:32:47 -0700 | [diff] [blame] | 1763 | well in all environments. It organizes cache hot objects in |
Simon Arlott | 02f5621 | 2008-11-05 22:18:19 +0000 | [diff] [blame] | 1764 | per cpu and per node queues. |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1765 | |
| 1766 | config SLUB |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1767 | bool "SLUB (Unqueued Allocator)" |
| 1768 | help |
| 1769 | SLUB is a slab allocator that minimizes cache line usage |
| 1770 | instead of managing queues of cached objects (SLAB approach). |
| 1771 | Per cpu caching is realized using slabs of objects instead |
| 1772 | of queues of objects. SLUB can use memory efficiently |
Simon Arlott | 02f5621 | 2008-11-05 22:18:19 +0000 | [diff] [blame] | 1773 | and has enhanced diagnostics. SLUB is the default choice for |
| 1774 | a slab allocator. |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1775 | |
| 1776 | config SLOB |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1777 | depends on EXPERT |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1778 | bool "SLOB (Simple Allocator)" |
| 1779 | help |
Matt Mackall | 3729145 | 2008-02-04 22:29:38 -0800 | [diff] [blame] | 1780 | SLOB replaces the stock allocator with a drastically simpler |
| 1781 | allocator. SLOB is generally more space efficient but |
| 1782 | does not perform as well on large systems. |
Christoph Lameter | 81819f0 | 2007-05-06 14:49:36 -0700 | [diff] [blame] | 1783 | |
| 1784 | endchoice |
| 1785 | |
Thomas Garnier | c7ce4f60 | 2016-05-19 17:10:37 -0700 | [diff] [blame] | 1786 | config SLAB_FREELIST_RANDOM |
| 1787 | default n |
| 1788 | depends on SLAB |
| 1789 | bool "SLAB freelist randomization" |
| 1790 | help |
| 1791 | Randomizes the freelist order used on creating new SLABs. This |
| 1792 | security feature reduces the predictability of the kernel slab |
| 1793 | allocator against heap overflows. |
| 1794 | |
Joonsoo Kim | 345c905 | 2013-06-19 14:05:52 +0900 | [diff] [blame] | 1795 | config SLUB_CPU_PARTIAL |
| 1796 | default y |
Uwe Kleine-König | b39ffbf | 2013-07-17 16:54:59 +0200 | [diff] [blame] | 1797 | depends on SLUB && SMP |
Joonsoo Kim | 345c905 | 2013-06-19 14:05:52 +0900 | [diff] [blame] | 1798 | bool "SLUB per cpu partial cache" |
| 1799 | help |
| 1800 | Per cpu partial caches accellerate objects allocation and freeing |
| 1801 | that is local to a processor at the price of more indeterminism |
| 1802 | in the latency of the free. On overflow these caches will be cleared |
| 1803 | which requires the taking of locks that may cause latency spikes. |
| 1804 | Typically one would choose no for a realtime system. |
| 1805 | |
Jie Zhang | ea63763 | 2009-12-14 18:00:02 -0800 | [diff] [blame] | 1806 | config MMAP_ALLOW_UNINITIALIZED |
| 1807 | bool "Allow mmapped anonymous memory to be uninitialized" |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1808 | depends on EXPERT && !MMU |
Jie Zhang | ea63763 | 2009-12-14 18:00:02 -0800 | [diff] [blame] | 1809 | default n |
| 1810 | help |
| 1811 | Normally, and according to the Linux spec, anonymous memory obtained |
| 1812 | from mmap() has it's contents cleared before it is passed to |
| 1813 | userspace. Enabling this config option allows you to request that |
| 1814 | mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus |
| 1815 | providing a huge performance boost. If this option is not enabled, |
| 1816 | then the flag will be ignored. |
| 1817 | |
| 1818 | This is taken advantage of by uClibc's malloc(), and also by |
| 1819 | ELF-FDPIC binfmt's brk and stack allocator. |
| 1820 | |
| 1821 | Because of the obvious security issues, this option should only be |
| 1822 | enabled on embedded devices where you control what is run in |
| 1823 | userspace. Since that isn't generally a problem on no-MMU systems, |
| 1824 | it is normally safe to say Y here. |
| 1825 | |
| 1826 | See Documentation/nommu-mmap.txt for more information. |
| 1827 | |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 1828 | config SYSTEM_DATA_VERIFICATION |
| 1829 | def_bool n |
| 1830 | select SYSTEM_TRUSTED_KEYRING |
| 1831 | select KEYS |
| 1832 | select CRYPTO |
David Howells | d43de6c | 2016-03-03 21:49:27 +0000 | [diff] [blame] | 1833 | select CRYPTO_RSA |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 1834 | select ASYMMETRIC_KEY_TYPE |
| 1835 | select ASYMMETRIC_PUBLIC_KEY_SUBTYPE |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 1836 | select ASN1 |
| 1837 | select OID_REGISTRY |
| 1838 | select X509_CERTIFICATE_PARSER |
| 1839 | select PKCS7_MESSAGE_PARSER |
Peter Foley | 82c04ff | 2014-04-18 15:07:11 -0700 | [diff] [blame] | 1840 | help |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 1841 | Provide PKCS#7 message verification using the contents of the system |
| 1842 | trusted keyring to provide public keys. This then can be used for |
| 1843 | module verification, kexec image verification and firmware blob |
| 1844 | verification. |
Peter Foley | 82c04ff | 2014-04-18 15:07:11 -0700 | [diff] [blame] | 1845 | |
Mathieu Desnoyers | 125e564 | 2008-02-02 15:10:36 -0500 | [diff] [blame] | 1846 | config PROFILING |
Robert Richter | b309a29 | 2010-02-26 15:01:23 +0100 | [diff] [blame] | 1847 | bool "Profiling support" |
Mathieu Desnoyers | 125e564 | 2008-02-02 15:10:36 -0500 | [diff] [blame] | 1848 | help |
| 1849 | Say Y here to enable the extended profiling support mechanisms used |
| 1850 | by profilers such as OProfile. |
| 1851 | |
Ingo Molnar | 5f87f11 | 2008-07-23 14:15:22 +0200 | [diff] [blame] | 1852 | # |
| 1853 | # Place an empty function call at each tracepoint site. Can be |
| 1854 | # dynamically changed for a probe function. |
| 1855 | # |
Mathieu Desnoyers | 97e1c18 | 2008-07-18 12:16:16 -0400 | [diff] [blame] | 1856 | config TRACEPOINTS |
Ingo Molnar | 5f87f11 | 2008-07-23 14:15:22 +0200 | [diff] [blame] | 1857 | bool |
Mathieu Desnoyers | 97e1c18 | 2008-07-18 12:16:16 -0400 | [diff] [blame] | 1858 | |
Mathieu Desnoyers | fb32e03 | 2008-02-02 15:10:33 -0500 | [diff] [blame] | 1859 | source "arch/Kconfig" |
| 1860 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1861 | endmenu # General setup |
| 1862 | |
Dmitry Baryshkov | ee7e551 | 2008-06-29 14:18:46 +0400 | [diff] [blame] | 1863 | config HAVE_GENERIC_DMA_COHERENT |
| 1864 | bool |
| 1865 | default n |
| 1866 | |
Linus Torvalds | 158a962 | 2008-01-02 13:04:48 -0800 | [diff] [blame] | 1867 | config SLABINFO |
| 1868 | bool |
| 1869 | depends on PROC_FS |
Christoph Lameter | 0f389ec | 2008-04-14 18:53:02 +0300 | [diff] [blame] | 1870 | depends on SLAB || SLUB_DEBUG |
Linus Torvalds | 158a962 | 2008-01-02 13:04:48 -0800 | [diff] [blame] | 1871 | default y |
| 1872 | |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 1873 | config RT_MUTEXES |
Christoph Jaeger | 6341e62 | 2014-12-20 15:41:11 -0500 | [diff] [blame] | 1874 | bool |
Chuck Ebbert | ae81f9e | 2006-09-16 12:15:53 -0700 | [diff] [blame] | 1875 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1876 | config BASE_SMALL |
| 1877 | int |
| 1878 | default 0 if BASE_FULL |
| 1879 | default 1 if !BASE_FULL |
| 1880 | |
Jan Engelhardt | 66da573 | 2007-07-15 23:39:29 -0700 | [diff] [blame] | 1881 | menuconfig MODULES |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1882 | bool "Enable loadable module support" |
Yann E. MORIN | 11097a0 | 2013-08-11 16:07:50 +0200 | [diff] [blame] | 1883 | option modules |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1884 | help |
| 1885 | Kernel modules are small pieces of compiled code which can |
| 1886 | be inserted in the running kernel, rather than being |
| 1887 | permanently built into the kernel. You use the "modprobe" |
| 1888 | tool to add (and sometimes remove) them. If you say Y here, |
| 1889 | many parts of the kernel can be built as modules (by |
| 1890 | answering M instead of Y where indicated): this is most |
| 1891 | useful for infrequently used options which are not required |
| 1892 | for booting. For more information, see the man pages for |
| 1893 | modprobe, lsmod, modinfo, insmod and rmmod. |
| 1894 | |
| 1895 | If you say Y here, you will need to run "make |
| 1896 | modules_install" to put the modules under /lib/modules/ |
| 1897 | where modprobe can find them (you may need to be root to do |
| 1898 | this). |
| 1899 | |
| 1900 | If unsure, say Y. |
| 1901 | |
Robert P. J. Day | 0b0de14 | 2008-08-04 13:31:32 -0400 | [diff] [blame] | 1902 | if MODULES |
| 1903 | |
Linus Torvalds | 826e450 | 2008-05-04 17:04:16 -0700 | [diff] [blame] | 1904 | config MODULE_FORCE_LOAD |
| 1905 | bool "Forced module loading" |
Linus Torvalds | 826e450 | 2008-05-04 17:04:16 -0700 | [diff] [blame] | 1906 | default n |
| 1907 | help |
Rusty Russell | 91e37a7 | 2008-05-09 16:25:28 +1000 | [diff] [blame] | 1908 | Allow loading of modules without version information (ie. modprobe |
| 1909 | --force). Forced module loading sets the 'F' (forced) taint flag and |
| 1910 | is usually a really bad idea. |
Linus Torvalds | 826e450 | 2008-05-04 17:04:16 -0700 | [diff] [blame] | 1911 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1912 | config MODULE_UNLOAD |
| 1913 | bool "Module unloading" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1914 | help |
| 1915 | Without this option you will not be able to unload any |
| 1916 | modules (note that some modules may not be unloadable |
Denys Vlasenko | f7f5b67 | 2008-07-22 19:24:26 -0500 | [diff] [blame] | 1917 | anyway), which makes your kernel smaller, faster |
| 1918 | and simpler. If unsure, say Y. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1919 | |
| 1920 | config MODULE_FORCE_UNLOAD |
| 1921 | bool "Forced module unloading" |
Kees Cook | 19c9239 | 2012-10-02 11:19:29 -0700 | [diff] [blame] | 1922 | depends on MODULE_UNLOAD |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1923 | help |
| 1924 | This option allows you to force a module to unload, even if the |
| 1925 | kernel believes it is unsafe: the kernel will remove the module |
| 1926 | without waiting for anyone to stop using it (using the -f option to |
| 1927 | rmmod). This is mainly for kernel developers and desperate users. |
| 1928 | If unsure, say N. |
| 1929 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1930 | config MODVERSIONS |
Sam Ravnborg | 0d54164 | 2005-12-26 23:04:02 +0100 | [diff] [blame] | 1931 | bool "Module versioning support" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1932 | help |
| 1933 | Usually, you have to use modules compiled with your kernel. |
| 1934 | Saying Y here makes it sometimes possible to use modules |
| 1935 | compiled for different kernels, by adding enough information |
| 1936 | to the modules to (hopefully) spot any changes which would |
| 1937 | make them incompatible with the kernel you are running. If |
| 1938 | unsure, say N. |
| 1939 | |
| 1940 | config MODULE_SRCVERSION_ALL |
| 1941 | bool "Source checksum for all modules" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1942 | help |
| 1943 | Modules which contain a MODULE_VERSION get an extra "srcversion" |
| 1944 | field inserted into their modinfo section, which contains a |
| 1945 | sum of the source files which made it. This helps maintainers |
| 1946 | see exactly which source was used to build a module (since |
| 1947 | others sometimes change the module source without updating |
| 1948 | the version). With this option, such a "srcversion" field |
| 1949 | will be created for all modules. If unsure, say N. |
| 1950 | |
Rusty Russell | 106a4ee | 2012-09-26 10:09:40 +0100 | [diff] [blame] | 1951 | config MODULE_SIG |
| 1952 | bool "Module signature verification" |
| 1953 | depends on MODULES |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 1954 | select SYSTEM_DATA_VERIFICATION |
Rusty Russell | 106a4ee | 2012-09-26 10:09:40 +0100 | [diff] [blame] | 1955 | help |
| 1956 | Check modules for valid signatures upon load: the signature |
| 1957 | is simply appended to the module. For more information see |
| 1958 | Documentation/module-signing.txt. |
| 1959 | |
David Howells | 228c37f | 2015-08-11 12:38:54 +0100 | [diff] [blame] | 1960 | Note that this option adds the OpenSSL development packages as a |
| 1961 | kernel build dependency so that the signing tool can use its crypto |
| 1962 | library. |
| 1963 | |
David Howells | ea0b6dc | 2012-09-26 10:09:50 +0100 | [diff] [blame] | 1964 | !!!WARNING!!! If you enable this option, you MUST make sure that the |
| 1965 | module DOES NOT get stripped after being signed. This includes the |
| 1966 | debuginfo strip done by some packagers (such as rpmbuild) and |
| 1967 | inclusion into an initramfs that wants the module size reduced. |
| 1968 | |
Rusty Russell | 106a4ee | 2012-09-26 10:09:40 +0100 | [diff] [blame] | 1969 | config MODULE_SIG_FORCE |
| 1970 | bool "Require modules to be validly signed" |
| 1971 | depends on MODULE_SIG |
| 1972 | help |
| 1973 | Reject unsigned modules or signed modules for which we don't have a |
| 1974 | key. Without this, such modules will simply taint the kernel. |
David Howells | ea0b6dc | 2012-09-26 10:09:50 +0100 | [diff] [blame] | 1975 | |
Michal Marek | d9d8d7e | 2013-01-25 13:41:31 +1030 | [diff] [blame] | 1976 | config MODULE_SIG_ALL |
| 1977 | bool "Automatically sign all modules" |
| 1978 | default y |
| 1979 | depends on MODULE_SIG |
| 1980 | help |
| 1981 | Sign all modules during make modules_install. Without this option, |
| 1982 | modules must be signed manually, using the scripts/sign-file tool. |
| 1983 | |
| 1984 | comment "Do not forget to sign required modules with scripts/sign-file" |
| 1985 | depends on MODULE_SIG_FORCE && !MODULE_SIG_ALL |
| 1986 | |
David Howells | ea0b6dc | 2012-09-26 10:09:50 +0100 | [diff] [blame] | 1987 | choice |
| 1988 | prompt "Which hash algorithm should modules be signed with?" |
| 1989 | depends on MODULE_SIG |
| 1990 | help |
| 1991 | This determines which sort of hashing algorithm will be used during |
| 1992 | signature generation. This algorithm _must_ be built into the kernel |
| 1993 | directly so that signature verification can take place. It is not |
| 1994 | possible to load a signed module containing the algorithm to check |
| 1995 | the signature on that module. |
| 1996 | |
| 1997 | config MODULE_SIG_SHA1 |
| 1998 | bool "Sign modules with SHA-1" |
| 1999 | select CRYPTO_SHA1 |
| 2000 | |
| 2001 | config MODULE_SIG_SHA224 |
| 2002 | bool "Sign modules with SHA-224" |
| 2003 | select CRYPTO_SHA256 |
| 2004 | |
| 2005 | config MODULE_SIG_SHA256 |
| 2006 | bool "Sign modules with SHA-256" |
| 2007 | select CRYPTO_SHA256 |
| 2008 | |
| 2009 | config MODULE_SIG_SHA384 |
| 2010 | bool "Sign modules with SHA-384" |
| 2011 | select CRYPTO_SHA512 |
| 2012 | |
| 2013 | config MODULE_SIG_SHA512 |
| 2014 | bool "Sign modules with SHA-512" |
| 2015 | select CRYPTO_SHA512 |
| 2016 | |
| 2017 | endchoice |
| 2018 | |
Michal Marek | 2275367 | 2013-01-25 13:41:00 +1030 | [diff] [blame] | 2019 | config MODULE_SIG_HASH |
| 2020 | string |
| 2021 | depends on MODULE_SIG |
| 2022 | default "sha1" if MODULE_SIG_SHA1 |
| 2023 | default "sha224" if MODULE_SIG_SHA224 |
| 2024 | default "sha256" if MODULE_SIG_SHA256 |
| 2025 | default "sha384" if MODULE_SIG_SHA384 |
| 2026 | default "sha512" if MODULE_SIG_SHA512 |
| 2027 | |
Bertrand Jacquin | beb50df | 2014-08-27 20:31:56 +0930 | [diff] [blame] | 2028 | config MODULE_COMPRESS |
| 2029 | bool "Compress modules on installation" |
| 2030 | depends on MODULES |
| 2031 | help |
Bertrand Jacquin | beb50df | 2014-08-27 20:31:56 +0930 | [diff] [blame] | 2032 | |
Rusty Russell | b6c09b5 | 2015-06-16 12:16:22 +0930 | [diff] [blame] | 2033 | Compresses kernel modules when 'make modules_install' is run; gzip or |
| 2034 | xz depending on "Compression algorithm" below. |
Bertrand Jacquin | beb50df | 2014-08-27 20:31:56 +0930 | [diff] [blame] | 2035 | |
Rusty Russell | b6c09b5 | 2015-06-16 12:16:22 +0930 | [diff] [blame] | 2036 | module-init-tools MAY support gzip, and kmod MAY support gzip and xz. |
Bertrand Jacquin | beb50df | 2014-08-27 20:31:56 +0930 | [diff] [blame] | 2037 | |
Rusty Russell | b6c09b5 | 2015-06-16 12:16:22 +0930 | [diff] [blame] | 2038 | Out-of-tree kernel modules installed using Kbuild will also be |
| 2039 | compressed upon installation. |
Bertrand Jacquin | beb50df | 2014-08-27 20:31:56 +0930 | [diff] [blame] | 2040 | |
Rusty Russell | b6c09b5 | 2015-06-16 12:16:22 +0930 | [diff] [blame] | 2041 | Note: for modules inside an initrd or initramfs, it's more efficient |
| 2042 | to compress the whole initrd or initramfs instead. |
Bertrand Jacquin | beb50df | 2014-08-27 20:31:56 +0930 | [diff] [blame] | 2043 | |
Rusty Russell | b6c09b5 | 2015-06-16 12:16:22 +0930 | [diff] [blame] | 2044 | Note: This is fully compatible with signed modules. |
| 2045 | |
| 2046 | If in doubt, say N. |
Bertrand Jacquin | beb50df | 2014-08-27 20:31:56 +0930 | [diff] [blame] | 2047 | |
| 2048 | choice |
| 2049 | prompt "Compression algorithm" |
| 2050 | depends on MODULE_COMPRESS |
| 2051 | default MODULE_COMPRESS_GZIP |
| 2052 | help |
| 2053 | This determines which sort of compression will be used during |
| 2054 | 'make modules_install'. |
| 2055 | |
| 2056 | GZIP (default) and XZ are supported. |
| 2057 | |
| 2058 | config MODULE_COMPRESS_GZIP |
| 2059 | bool "GZIP" |
| 2060 | |
| 2061 | config MODULE_COMPRESS_XZ |
| 2062 | bool "XZ" |
| 2063 | |
| 2064 | endchoice |
| 2065 | |
Nicolas Pitre | dbacb0e | 2016-01-26 21:51:05 -0500 | [diff] [blame] | 2066 | config TRIM_UNUSED_KSYMS |
| 2067 | bool "Trim unused exported kernel symbols" |
| 2068 | depends on MODULES && !UNUSED_SYMBOLS |
| 2069 | help |
| 2070 | The kernel and some modules make many symbols available for |
| 2071 | other modules to use via EXPORT_SYMBOL() and variants. Depending |
| 2072 | on the set of modules being selected in your kernel configuration, |
| 2073 | many of those exported symbols might never be used. |
| 2074 | |
| 2075 | This option allows for unused exported symbols to be dropped from |
| 2076 | the build. In turn, this provides the compiler more opportunities |
| 2077 | (especially when using LTO) for optimizing the code and reducing |
| 2078 | binary size. This might have some security advantages as well. |
| 2079 | |
| 2080 | If unsure say N. |
| 2081 | |
Robert P. J. Day | 0b0de14 | 2008-08-04 13:31:32 -0400 | [diff] [blame] | 2082 | endif # MODULES |
| 2083 | |
Peter Zijlstra | 6c9692e | 2015-05-27 11:09:37 +0930 | [diff] [blame] | 2084 | config MODULES_TREE_LOOKUP |
| 2085 | def_bool y |
| 2086 | depends on PERF_EVENTS || TRACING |
| 2087 | |
Rusty Russell | 98a79d6 | 2008-12-13 21:19:41 +1030 | [diff] [blame] | 2088 | config INIT_ALL_POSSIBLE |
| 2089 | bool |
| 2090 | help |
Rusty Russell | 5f054e3 | 2012-03-29 15:38:31 +1030 | [diff] [blame] | 2091 | Back when each arch used to define their own cpu_online_mask and |
| 2092 | cpu_possible_mask, some of them chose to initialize cpu_possible_mask |
Rusty Russell | 98a79d6 | 2008-12-13 21:19:41 +1030 | [diff] [blame] | 2093 | with all 1s, and others with all 0s. When they were centralised, |
| 2094 | 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] | 2095 | and have several arch maintainers pursuing me down dark alleys. |
Rusty Russell | 98a79d6 | 2008-12-13 21:19:41 +1030 | [diff] [blame] | 2096 | |
Jens Axboe | 3a65dfe | 2005-11-04 08:43:35 +0100 | [diff] [blame] | 2097 | source "block/Kconfig" |
Avi Kivity | e98c320 | 2007-10-16 23:27:31 -0700 | [diff] [blame] | 2098 | |
| 2099 | config PREEMPT_NOTIFIERS |
| 2100 | bool |
Paul E. McKenney | e260be6 | 2008-01-25 21:08:24 +0100 | [diff] [blame] | 2101 | |
Steffen Klassert | 16295be | 2010-01-06 19:47:10 +1100 | [diff] [blame] | 2102 | config PADATA |
| 2103 | depends on SMP |
| 2104 | bool |
| 2105 | |
Andi Kleen | 754b7b6 | 2012-10-04 17:11:27 -0700 | [diff] [blame] | 2106 | # Can be selected by architectures with broken toolchains |
| 2107 | # that get confused by correct const<->read_only section |
| 2108 | # mappings |
| 2109 | config BROKEN_RODATA |
| 2110 | bool |
| 2111 | |
David Howells | 4520c6a | 2012-09-21 23:31:13 +0100 | [diff] [blame] | 2112 | config ASN1 |
| 2113 | tristate |
| 2114 | help |
| 2115 | Build a simple ASN.1 grammar compiler that produces a bytecode output |
| 2116 | that can be interpreted by the ASN.1 stream decoder and used to |
| 2117 | inform it as to what tags are to be expected in a stream and what |
| 2118 | functions to call on what tags. |
| 2119 | |
Thomas Gleixner | 6beb000 | 2009-11-09 15:21:34 +0000 | [diff] [blame] | 2120 | source "kernel/Kconfig.locks" |