default "/lib/modules/$UNAME_RELEASE/.config"
default "/etc/kernel-config"
default "/boot/config-$UNAME_RELEASE"
+ default "$ARCH_DEFCONFIG"
default "arch/$ARCH/defconfig"
menu "General setup"
process and it's parent. Note that this file format is incompatible
with previous v0/v1/v2 file formats, so you will need updated tools
for processing it. A preliminary version of these tools is available
- at <http://www.physik3.uni-rostock.de/tim/kernel/utils/acct/>.
+ at <http://www.gnu.org/software/acct/>.
config TASKSTATS
bool "Export task/process statistics through netlink (EXPERIMENTAL)"
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 PID_NS
- bool "PID Namespaces (EXPERIMENTAL)"
- default n
- depends on EXPERIMENTAL
- help
- Suport process id namespaces. This allows having multiple
- process with the same pid as long as they are in different
- pid namespaces. This is a building block of containers.
-
- Unless you want to work with an experimental feature
- say N here.
-
config AUDIT
bool "Auditing support"
depends on NET
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
+ default 17
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
+ Examples:
+ 17 => 128 KB
+ 16 => 64 KB
+ 15 => 32 KB
+ 14 => 16 KB
13 => 8 KB
12 => 4 KB
config CGROUP_DEBUG
bool "Example debug cgroup subsystem"
depends on CGROUPS
+ default n
help
This option enables a simple cgroup subsystem that
exports useful debugging information about the cgroups
for instance virtual servers and checkpoint/restart
jobs.
+config CGROUP_FREEZER
+ bool "control group freezer subsystem"
+ depends on CGROUPS
+ help
+ Provides a way to freeze and unfreeze all tasks in a
+ cgroup.
+
+config CGROUP_DEVICE
+ bool "Device controller for cgroups"
+ depends on CGROUPS && EXPERIMENTAL
+ help
+ Provides a cgroup implementing whitelists for devices which
+ a process in the cgroup can mknod or open.
+
config CPUSETS
bool "Cpuset support"
depends on SMP && CGROUPS
Say N if unsure.
-config FAIR_GROUP_SCHED
- bool "Fair group CPU scheduler"
- default y
+#
+# Architectures with an unreliable sched_clock() should select this:
+#
+config HAVE_UNSTABLE_SCHED_CLOCK
+ bool
+
+config GROUP_SCHED
+ bool "Group CPU scheduler"
+ depends on EXPERIMENTAL
+ default n
help
This feature lets CPU scheduler recognize task groups and control CPU
bandwidth allocation to such task groups.
+config FAIR_GROUP_SCHED
+ bool "Group scheduling for SCHED_OTHER"
+ depends on GROUP_SCHED
+ default GROUP_SCHED
+
+config RT_GROUP_SCHED
+ bool "Group scheduling for SCHED_RR/FIFO"
+ depends on EXPERIMENTAL
+ depends on GROUP_SCHED
+ default n
+ help
+ This feature lets you explicitly allocate real CPU bandwidth
+ to users or control groups (depending on the "Basis for grouping tasks"
+ setting below. If enabled, it will also make it impossible to
+ schedule realtime tasks for non-root users until you allocate
+ realtime bandwidth for them.
+ See Documentation/sched-rt-group.txt for more information.
+
choice
- depends on FAIR_GROUP_SCHED
+ depends on GROUP_SCHED
prompt "Basis for grouping tasks"
- default FAIR_USER_SCHED
+ default USER_SCHED
-config FAIR_USER_SCHED
+config USER_SCHED
bool "user id"
help
This option will choose userid as the basis for grouping
tasks, thus providing equal CPU bandwidth to each user.
-config FAIR_CGROUP_SCHED
+config CGROUP_SCHED
bool "Control groups"
depends on CGROUPS
help
infrastructure that works with cgroups
depends on CGROUPS
+config MM_OWNER
+ bool
+
+config CGROUP_MEM_RES_CTLR
+ bool "Memory Resource Controller for Control Groups"
+ depends on CGROUPS && RESOURCE_COUNTERS
+ select MM_OWNER
+ help
+ Provides a memory resource controller that manages both page cache and
+ RSS memory.
+
+ Note that setting this option increases fixed memory overhead
+ associated with each page of memory in the system by 4/8 bytes
+ and also increases cache misses because struct page on many 64bit
+ systems will not fit into a single cache line anymore.
+
+ Only enable when you're ok with these trade offs and really
+ sure you need the memory resource controller.
+
+ This config option also selects MM_OWNER config option, which
+ could in turn add some fork/exit overhead.
+
config SYSFS_DEPRECATED
+ bool
+
+config SYSFS_DEPRECATED_V2
bool "Create deprecated sysfs files"
depends on SYSFS
default y
+ select SYSFS_DEPRECATED
help
This option creates deprecated symlinks such as the
"device"-link, the <subsystem>:<name>-link, and the
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.
+ order to support older versions of udev and some userspace
+ programs.
- If you are using a distro that was released in 2006 or later,
- it should be safe to say N here.
-
-config CGROUP_MEM_CONT
- bool "Memory controller for cgroups"
- depends on CGROUPS && RESOURCE_COUNTERS
- help
- Provides a memory controller that manages both page cache and
- RSS memory.
+ If you are using a distro with the most recent userspace
+ packages, it should be safe to say N here.
config PROC_PID_CPUSET
bool "Include legacy /proc/<pid>/cpuset file"
In this namespace tasks see different info provided with the
uname() system call
+config IPC_NS
+ bool "IPC namespace"
+ depends on NAMESPACES && SYSVIPC
+ help
+ In this namespace tasks work with IPC ids which correspond to
+ different IPC objects in different namespaces
+
+config USER_NS
+ bool "User namespace (EXPERIMENTAL)"
+ depends on NAMESPACES && EXPERIMENTAL
+ help
+ This allows containers, i.e. vservers, to use user namespaces
+ to provide different user info for different servers.
+ If unsure, say N.
+
+config PID_NS
+ bool "PID Namespaces (EXPERIMENTAL)"
+ default n
+ depends on NAMESPACES && EXPERIMENTAL
+ help
+ Support process id namespaces. This allows having multiple
+ process with the same pid as long as they are in different
+ pid namespaces. This is a building block of containers.
+
+ Unless you want to work with an experimental feature
+ say N here.
+
config BLK_DEV_INITRD
bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
depends on BROKEN || !FRV
endif
config CC_OPTIMIZE_FOR_SIZE
- bool "Optimize for size (Look out for broken compilers!)"
+ bool "Optimize for size"
default y
- depends on ARM || H8300 || SUPERH || EXPERIMENTAL
help
Enabling this option will pass "-Os" instead of "-O2" to gcc
resulting in a smaller kernel.
- WARNING: some versions of gcc may generate incorrect code with this
- option. If problems are observed, a gcc upgrade may be needed.
-
- If unsure, say N.
+ If unsure, say Y.
config SYSCTL
bool
config UID16
bool "Enable 16-bit UID system calls" if EMBEDDED
- depends on ARM || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && SPARC32_COMPAT) || UML || (X86_64 && IA32_EMULATION)
+ depends on ARM || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && COMPAT) || UML || (X86_64 && IA32_EMULATION)
default y
help
This enables the legacy 16-bit UID syscall wrappers.
help
Enable support for generating core dumps. Disabling saves about 4k.
+config PCSPKR_PLATFORM
+ bool "Enable PC-Speaker support" if EMBEDDED
+ depends on ALPHA || X86 || MIPS || PPC_PREP || PPC_CHRP || PPC_PSERIES
+ default y
+ help
+ This option allows to disable the internal PC-Speaker
+ support, saving some memory.
+
config COMPAT_BRK
bool "Disable heap randomization"
default y
disabled, and can be overriden runtime by setting
/proc/sys/kernel/randomize_va_space to 2.
- On non-ancient distros (post-2000 ones) Y is usually a safe choice.
+ On non-ancient distros (post-2000 ones) N is usually a safe choice.
config BASE_FULL
default y
option replaces shmem and tmpfs with the much simpler ramfs code,
which may be appropriate on small systems without swap.
+config AIO
+ bool "Enable AIO support" if EMBEDDED
+ default y
+ help
+ This option enables POSIX asynchronous I/O which may by used
+ by some high performance threaded applications. Disabling
+ this option saves about 7k.
+
config VM_EVENT_COUNTERS
default y
bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
config SLUB_DEBUG
default y
bool "Enable SLUB debugging support" if EMBEDDED
- depends on SLUB
+ depends on SLUB && SYSFS
help
SLUB has extensive debug support features. Disabling these can
result in significant savings in code size. This also disables
source "arch/Kconfig"
-config PROC_PAGE_MONITOR
- default y
- depends on PROC_FS && MMU
- bool "Enable /proc page monitoring" if EMBEDDED
- help
- Various /proc files exist to monitor process memory utilization:
- /proc/pid/smaps, /proc/pid/clear_refs, /proc/pid/pagemap,
- /proc/kpagecount, and /proc/kpageflags. Disabling these
- interfaces will reduce the size of the kernel by approximately 4kb.
-
endmenu # General setup
+config HAVE_GENERIC_DMA_COHERENT
+ bool
+ default n
+
config SLABINFO
bool
depends on PROC_FS
- depends on SLAB || SLUB
+ depends on SLAB || SLUB_DEBUG
default y
config RT_MUTEXES
If unsure, say Y.
+if MODULES
+
+config MODULE_FORCE_LOAD
+ bool "Forced module loading"
+ default n
+ help
+ Allow loading of modules without version information (ie. modprobe
+ --force). Forced module loading sets the 'F' (forced) taint flag and
+ is usually a really bad idea.
+
config MODULE_UNLOAD
bool "Module unloading"
- depends on MODULES
help
Without this option you will not be able to unload any
modules (note that some modules may not be unloadable
- anyway), which makes your kernel slightly smaller and
- simpler. If unsure, say Y.
+ anyway), which makes your kernel smaller, faster
+ and simpler. If unsure, say Y.
config MODULE_FORCE_UNLOAD
bool "Forced module unloading"
config MODVERSIONS
bool "Module versioning support"
- depends on MODULES
help
Usually, you have to use modules compiled with your kernel.
Saying Y here makes it sometimes possible to use modules
config MODULE_SRCVERSION_ALL
bool "Source checksum for all modules"
- depends on MODULES
help
Modules which contain a MODULE_VERSION get an extra "srcversion"
field inserted into their modinfo section, which contains a
will be created for all modules. If unsure, say N.
config KMOD
- bool "Automatic kernel module loading"
- depends on MODULES
+ def_bool y
help
- Normally when you have selected some parts of the kernel to
- be created as kernel modules, you must load them (using the
- "modprobe" command) before you can use them. If you say Y
- here, some parts of the kernel will be able to load modules
- automatically: when a part of the kernel needs a module, it
- runs modprobe with the appropriate arguments, thereby
- loading the module if it is available. If unsure, say Y.
+ This is being removed soon. These days, CONFIG_MODULES
+ implies CONFIG_KMOD, so use that instead.
+
+endif # MODULES
config STOP_MACHINE
bool
config PREEMPT_NOTIFIERS
bool
-choice
- prompt "RCU implementation type:"
- default CLASSIC_RCU
- help
- This allows you to choose either the classic RCU implementation
- that is designed for best read-side performance on non-realtime
- systems, or the preemptible RCU implementation for best latency
- on realtime systems. Note that some kernel preemption modes
- will restrict your choice.
-
- Select the default if you are unsure.
-
config CLASSIC_RCU
- bool "Classic RCU"
+ def_bool !PREEMPT_RCU
help
This option selects the classic RCU implementation that is
designed for best read-side performance on non-realtime
- systems.
-
- Say Y if you are unsure.
-
-config PREEMPT_RCU
- bool "Preemptible RCU"
- depends on PREEMPT
- help
- This option reduces the latency of the kernel by making certain
- RCU sections preemptible. Normally RCU code is non-preemptible, if
- this option is selected then read-only RCU sections become
- preemptible. This helps latency, but may expose bugs due to
- now-naive assumptions about each RCU read-side critical section
- remaining on a given CPU through its execution.
-
- Say N if you are unsure.
-
-endchoice
+ systems. Classic RCU is the default. Note that the
+ PREEMPT_RCU symbol is used to select/deselect this option.