config DEFCONFIG_LIST
string
+ depends on !UML
option defconfig_list
default "/lib/modules/$UNAME_RELEASE/.config"
default "/etc/kernel-config"
default "/boot/config-$UNAME_RELEASE"
default "arch/$ARCH/defconfig"
-menu "Code maturity level options"
+menu "General setup"
config EXPERIMENTAL
bool "Prompt for development and/or incomplete code/drivers"
Maximum of each of the number of arguments and environment
variables passed to init from the kernel command line.
-endmenu
-
-menu "General setup"
config LOCALVERSION
string "Local version - append to kernel release"
default y
help
This will try to automatically determine if the current tree is a
- release tree by looking for git tags that
- belong to the current top of tree revision.
+ release tree by looking for git tags that belong to the current
+ top of tree revision.
A string of the format -gxxxxxxxx will be added to the localversion
- if a git based tree is found. The string generated by this will be
+ if a git-based tree is found. The string generated by this will be
appended after any matching localversion* files, and after the value
- set in CONFIG_LOCALVERSION
+ set in CONFIG_LOCALVERSION.
+
+ (The actual string used here is the first eight characters produced
+ by running the command:
- Note: This requires Perl, and a git repository, but not necessarily
- the git or cogito tools to be installed.
+ $ git rev-parse --verify HEAD
+
+ which is done within the script "scripts/setlocalversion".)
config SWAP
bool "Support for paging of anonymous memory (swap)"
- depends on MMU
+ depends on MMU && BLOCK
default y
help
This option allows you to choose whether you want to have support
section 6.4 of the Linux Programmer's Guide, available from
<http://www.tldp.org/guides.html>.
+config SYSVIPC_SYSCTL
+ bool
+ depends on SYSVIPC
+ depends on SYSCTL
+ default y
+
config POSIX_MQUEUE
bool "POSIX Message Queues"
depends on NET && EXPERIMENTAL
queues every message has a priority which decides about succession
of receiving it by a process. If you want to compile and run
programs written e.g. for Solaris with use of its POSIX message
- queues (functions mq_*) say Y here. To use this feature you will
- also need mqueue library, available from
- <http://www.mat.uni.torun.pl/~wrona/posix_ipc/>
+ queues (functions mq_*) say Y here.
POSIX message queues are visible as a filesystem called 'mqueue'
and can be mounted somewhere if you want to do filesystem
config TASK_DELAY_ACCT
bool "Enable per-task delay accounting (EXPERIMENTAL)"
+ depends on TASKSTATS
help
Collect information on time spent by a task waiting for system
resources like cpu, synchronous block I/O completion and swapping
Say N if unsure.
-config SYSCTL
- bool "Sysctl support" if EMBEDDED
- default y
- ---help---
- The sysctl interface provides a means of dynamically changing
- certain kernel parameters and variables on the fly without requiring
- a recompile of the kernel or reboot of the system. The primary
- interface consists of a system call, but if you say Y to "/proc
- file system support", a tree of modifiable sysctl entries will be
- generated beneath the /proc/sys directory. They are explained in the
- files in <file:Documentation/sysctl/>. Note that enabling this
- option will enlarge the kernel by at least 8 KB.
-
- As it is generally a good thing, you should say Y here unless
- building a kernel for install/rescue disks or your system is very
- limited in memory.
+config TASK_XACCT
+ bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
+ depends on TASKSTATS
+ help
+ Collect extended task accounting data and send the data
+ to userland for processing over the taskstats interface.
+
+ Say N if unsure.
+
+config TASK_IO_ACCOUNTING
+ bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
+ depends on TASK_XACCT
+ help
+ Collect information on the number of bytes of storage I/O which this
+ task has caused.
+
+ Say N if unsure.
+
+config USER_NS
+ bool "User Namespaces (EXPERIMENTAL)"
+ default n
+ depends on EXPERIMENTAL
+ help
+ Support user namespaces. This allows containers, i.e.
+ vservers, to use user namespaces to provide different
+ user info for different servers. If unsure, say N.
config AUDIT
bool "Auditing support"
ensure that INOTIFY is configured.
config IKCONFIG
- bool "Kernel .config support"
+ tristate "Kernel .config support"
---help---
This option enables the complete Linux kernel ".config" file
contents to be saved in the kernel. It provides documentation
This option enables access to the kernel configuration file
through /proc/config.gz.
+config LOG_BUF_SHIFT
+ int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
+ range 12 21
+ default 17 if S390 || LOCKDEP
+ default 16 if X86_NUMAQ || IA64
+ default 15 if SMP
+ default 14
+ help
+ Select kernel log buffer size as a power of 2.
+ Defaults and Examples:
+ 17 => 128 KB for S/390
+ 16 => 64 KB for x86 NUMAQ or IA-64
+ 15 => 32 KB for SMP
+ 14 => 16 KB for uniprocessor
+ 13 => 8 KB
+ 12 => 4 KB
+
config CPUSETS
bool "Cpuset support"
depends on SMP
Say N if unsure.
+config SYSFS_DEPRECATED
+ bool "Create deprecated sysfs files"
+ default y
+ help
+ This option creates deprecated symlinks such as the
+ "device"-link, the <subsystem>:<name>-link, and the
+ "bus"-link. It may also add deprecated key in the
+ uevent environment.
+ None of these features or values should be used today, as
+ they export driver core implementation details to userspace
+ or export properties which can't be kept stable across kernel
+ releases.
+
+ If enabled, this option will also move any device structures
+ that belong to a class, back into the /sys/class hierarchy, in
+ order to support older versions of udev.
+
+ If you are using a distro that was released in 2006 or later,
+ it should be safe to say N here.
+
config RELAY
bool "Kernel->user space relay support (formerly relayfs)"
help
If unsure, say N.
+config BLK_DEV_INITRD
+ bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
+ depends on BROKEN || !FRV
+ help
+ The initial RAM filesystem is a ramfs which is loaded by the
+ boot loader (loadlin or lilo) and that is mounted as root
+ before the normal boot procedure. It is typically used to
+ load modules needed to mount the "real" root file system,
+ etc. See <file:Documentation/initrd.txt> for details.
+
+ If RAM disk support (BLK_DEV_RAM) is also included, this
+ also enables initial RAM disk (initrd) support and adds
+ 15 Kbytes (more on some other architectures) to the kernel size.
+
+ If unsure say Y.
+
+if BLK_DEV_INITRD
+
source "usr/Kconfig"
-config UID16
- bool "Enable 16-bit UID system calls" if EMBEDDED
- depends on ARM || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && SPARC32_COMPAT) || UML || (X86_64 && IA32_EMULATION)
- default y
- help
- This enables the legacy 16-bit UID syscall wrappers.
+endif
config CC_OPTIMIZE_FOR_SIZE
bool "Optimize for size (Look out for broken compilers!)"
default y
- depends on ARM || H8300 || EXPERIMENTAL
+ depends on ARM || H8300 || SUPERH || EXPERIMENTAL
help
Enabling this option will pass "-Os" instead of "-O2" to gcc
resulting in a smaller kernel.
If unsure, say N.
+config SYSCTL
+ bool
+
menuconfig EMBEDDED
bool "Configure standard kernel features (for small systems)"
help
environments which can tolerate a "non-standard" kernel.
Only use this if you really know what you are doing.
+config UID16
+ bool "Enable 16-bit UID system calls" if EMBEDDED
+ depends on ARM || BFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && SPARC32_COMPAT) || UML || (X86_64 && IA32_EMULATION)
+ default y
+ help
+ This enables the legacy 16-bit UID syscall wrappers.
+
+config SYSCTL_SYSCALL
+ bool "Sysctl syscall support" if EMBEDDED
+ default y
+ select SYSCTL
+ ---help---
+ sys_sysctl uses binary paths that have been found challenging
+ to properly maintain and use. The interface in /proc/sys
+ using paths with ascii names is now the primary path to this
+ information.
+
+ Almost nothing using the binary sysctl interface so if you are
+ trying to save some space it is probably safe to disable this,
+ making your kernel marginally smaller.
+
+ If unsure say Y here.
+
config KALLSYMS
- bool "Load all symbols for debugging/kksymoops" if EMBEDDED
+ bool "Load all symbols for debugging/ksymoops" if EMBEDDED
default y
help
Say Y here to let the kernel print out symbolic crash information and
kernel data structures. This saves memory on small machines,
but may reduce performance.
-config RT_MUTEXES
- boolean
- select PLIST
-
config FUTEX
bool "Enable futex support" if EMBEDDED
default y
support for "fast userspace mutexes". The resulting kernel may not
run glibc-based applications correctly.
+config ANON_INODES
+ bool
+
config EPOLL
bool "Enable eventpoll support" if EMBEDDED
default y
+ select ANON_INODES
help
Disabling this option will cause the kernel to be built without
support for epoll family of system calls.
+config SIGNALFD
+ bool "Enable signalfd() system call" if EMBEDDED
+ select ANON_INODES
+ default y
+ help
+ Enable the signalfd() system call that allows to receive signals
+ on a file descriptor.
+
+ If unsure, say Y.
+
+config TIMERFD
+ bool "Enable timerfd() system call" if EMBEDDED
+ select ANON_INODES
+ depends on BROKEN
+ default y
+ help
+ Enable the timerfd() system call that allows to receive timer
+ events on a file descriptor.
+
+ If unsure, say Y.
+
+config EVENTFD
+ bool "Enable eventfd() system call" if EMBEDDED
+ select ANON_INODES
+ default y
+ help
+ Enable the eventfd() system call that allows to receive both
+ kernel notification (ie. KAIO) or userspace notifications.
+
+ If unsure, say Y.
+
config SHMEM
bool "Use full shmem filesystem" if EMBEDDED
default y
option replaces shmem and tmpfs with the much simpler ramfs code,
which may be appropriate on small systems without swap.
-config SLAB
+config VM_EVENT_COUNTERS
default y
- bool "Use full SLAB allocator" if EMBEDDED
+ bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
help
- Disabling this replaces the advanced SLAB allocator and
- kmalloc support with the drastically simpler SLOB allocator.
- SLOB is more space efficient but does not scale well and is
- more susceptible to fragmentation.
+ VM event counters are needed for event counts to be shown.
+ This option allows the disabling of the VM event counters
+ on EMBEDDED systems. /proc/vmstat will only show page counts
+ if VM event counters are disabled.
-config VM_EVENT_COUNTERS
+config SLUB_DEBUG
default y
- bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
+ bool "Enable SLUB debugging support" if EMBEDDED
+ depends on SLUB
+ help
+ SLUB has extensive debug support features. Disabling these can
+ result in significant savings in code size. This also disables
+ SLUB sysfs support. /sys/slab will not exist and there will be
+ no support for cache validation etc.
+
+choice
+ prompt "Choose SLAB allocator"
+ default SLUB
+ help
+ This option allows to select a slab allocator.
+
+config SLAB
+ bool "SLAB"
+ help
+ The regular slab allocator that is established and known to work
+ well in all environments. It organizes cache hot objects in
+ per cpu and per node queues. SLAB is the default choice for
+ a slab allocator.
+
+config SLUB
+ bool "SLUB (Unqueued Allocator)"
help
- VM event counters are only needed to for event counts to be
- shown. They have no function for the kernel itself. This
- option allows the disabling of the VM event counters.
- /proc/vmstat will only show page counts.
+ SLUB is a slab allocator that minimizes cache line usage
+ instead of managing queues of cached objects (SLAB approach).
+ Per cpu caching is realized using slabs of objects instead
+ of queues of objects. SLUB can use memory efficiently
+ and has enhanced diagnostics.
+
+config SLOB
+ depends on EMBEDDED
+ bool "SLOB (Simple Allocator)"
+ help
+ SLOB replaces the SLAB allocator with a drastically simpler
+ allocator. SLOB is more space efficient than SLAB but does not
+ scale well (single lock for all operations) and is also highly
+ susceptible to fragmentation. SLUB can accomplish a higher object
+ density. It is usually better to use SLUB instead of SLOB.
+
+endchoice
endmenu # General setup
+config RT_MUTEXES
+ boolean
+ select PLIST
+
config TINY_SHMEM
default !SHMEM
bool
default 0 if BASE_FULL
default 1 if !BASE_FULL
-config SLOB
- default !SLAB
- bool
-
-menu "Loadable module support"
-
-config MODULES
+menuconfig MODULES
bool "Enable loadable module support"
help
Kernel modules are small pieces of compiled code which can
depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
help
Need stop_machine() primitive.
-endmenu
-menu "Block layer"
source "block/Kconfig"
-endmenu