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)"
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
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.
+ See Documentation/scheduler/sched-rt-group.txt for more information.
choice
depends on GROUP_SCHED
depends on CGROUPS && RESOURCE_COUNTERS
select MM_OWNER
help
- Provides a memory resource controller that manages both page cache and
- RSS memory.
+ Provides a memory resource controller that manages both anonymous
+ memory and page cache. (See Documentation/controllers/memory.txt)
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.
+ associated with each page of memory in the system. By this,
+ 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
+ usage tracking struct at boot. Total amount of this is printed out
+ at boot.
Only enable when you're ok with these trade offs and really
- sure you need the memory resource controller.
+ sure you need the memory resource controller. Even when you enable
+ this, you can set "cgroup_disable=memory" at your boot option to
+ disable memory resource controller and you can avoid overheads.
+ (and lose benefits of memory resource contoller)
This config option also selects MM_OWNER config option, which
could in turn add some fork/exit overhead.
default n
depends on NAMESPACES && EXPERIMENTAL
help
- Suport process id namespaces. This allows having multiple
+ 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.
Enabling this option will pass "-Os" instead of "-O2" to gcc
resulting in a smaller kernel.
- If unsure, say N.
+ If unsure, say Y.
config SYSCTL
bool
If unsure say Y here.
-config SYSCTL_SYSCALL_CHECK
- bool "Sysctl checks" if EMBEDDED
- depends on SYSCTL_SYSCALL
- default y
- ---help---
- sys_sysctl uses binary paths that have been found challenging
- to properly maintain and use. This enables checks that help
- you to keep things correct.
-
- If unsure say Y here.
-
config KALLSYMS
bool "Load all symbols for debugging/ksymoops" if EMBEDDED
default y
Say N.
+config KALLSYMS_STRIP_GENERATED
+ bool "Strip machine generated symbols from kallsyms"
+ depends on KALLSYMS_ALL
+ default y
+ help
+ Say N if you want kallsyms to retain even machine generated symbols.
+
config KALLSYMS_EXTRA_PASS
bool "Do an extra kallsyms pass"
depends on KALLSYMS
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
on EMBEDDED systems. /proc/vmstat will only show page counts
if VM event counters are disabled.
+config PCI_QUIRKS
+ default y
+ bool "Enable PCI quirk workarounds" if EMBEDDED
+ depends on PCI
+ help
+ This enables workarounds for various PCI chipset
+ bugs/quirks. Disable this only if your target machine is
+ unaffected by PCI quirks.
+
config SLUB_DEBUG
default y
bool "Enable SLUB debugging support" if EMBEDDED
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.
+ per cpu and per node queues.
config SLUB
bool "SLUB (Unqueued Allocator)"
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.
+ and has enhanced diagnostics. SLUB is the default choice for
+ a slab allocator.
config SLOB
depends on EMBEDDED
Say Y here to enable the extended profiling support mechanisms used
by profilers such as OProfile.
+#
+# Place an empty function call at each tracepoint site. Can be
+# dynamically changed for a probe function.
+#
+config TRACEPOINTS
+ bool
+
config MARKERS
bool "Activate markers"
+ depends on TRACEPOINTS
help
Place an empty function call at each marker site. Can be
dynamically changed for a probe function.
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
If unsure, say Y.
+if MODULES
+
config MODULE_FORCE_LOAD
bool "Forced module loading"
- depends on MODULES
default n
help
Allow loading of modules without version information (ie. modprobe
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
+ This is being removed soon. These days, CONFIG_MODULES
+ implies CONFIG_KMOD, so use that instead.
+
+endif # MODULES
+
+config INIT_ALL_POSSIBLE
+ bool
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.
+ Back when each arch used to define their own cpu_online_map and
+ cpu_possible_map, some of them chose to initialize cpu_possible_map
+ with all 1s, and others with all 0s. When they were centralised,
+ it was better to provide this option than to break all the archs
+ and have several arch maintainers persuing me down dark alleys.
config STOP_MACHINE
bool
config PREEMPT_NOTIFIERS
bool
+choice
+ prompt "RCU Implementation"
+ default CLASSIC_RCU
+
config CLASSIC_RCU
- def_bool !PREEMPT_RCU
+ bool "Classic RCU"
help
This option selects the classic RCU implementation that is
designed for best read-side performance on non-realtime
- systems. Classic RCU is the default. Note that the
- PREEMPT_RCU symbol is used to select/deselect this option.
+ systems.
+
+ Select this option if you are unsure.
+
+config TREE_RCU
+ bool "Tree-based hierarchical RCU"
+ help
+ This option selects the RCU implementation that is
+ designed for very large SMP system with hundreds or
+ thousands of CPUs.
+
+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.
+
+endchoice
+
+config RCU_TRACE
+ bool "Enable tracing for RCU"
+ depends on TREE_RCU || PREEMPT_RCU
+ help
+ This option provides tracing in RCU which presents stats
+ in debugfs for debugging RCU implementation.
+
+ Say Y here if you want to enable RCU tracing
+ Say N if you are unsure.
+
+config RCU_FANOUT
+ int "Tree-based hierarchical RCU fanout value"
+ range 2 64 if 64BIT
+ range 2 32 if !64BIT
+ depends on TREE_RCU
+ default 64 if 64BIT
+ default 32 if !64BIT
+ help
+ This option controls the fanout of hierarchical implementations
+ of RCU, allowing RCU to work efficiently on machines with
+ large numbers of CPUs. This value must be at least the cube
+ root of NR_CPUS, which allows NR_CPUS up to 32,768 for 32-bit
+ systems and up to 262,144 for 64-bit systems.
+
+ Select a specific number if testing RCU itself.
+ Take the default if unsure.
+
+config RCU_FANOUT_EXACT
+ bool "Disable tree-based hierarchical RCU auto-balancing"
+ depends on TREE_RCU
+ default n
+ help
+ This option forces use of the exact RCU_FANOUT value specified,
+ regardless of imbalances in the hierarchy. This is useful for
+ testing RCU itself, and might one day be useful on systems with
+ strong NUMA behavior.
+
+ Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
+
+ Say N if unsure.
+
+config TREE_RCU_TRACE
+ def_bool RCU_TRACE && TREE_RCU
+ select DEBUG_FS
+ help
+ This option provides tracing for the TREE_RCU implementation,
+ permitting Makefile to trivially select kernel/rcutree_trace.c.
+
+config PREEMPT_RCU_TRACE
+ def_bool RCU_TRACE && PREEMPT_RCU
+ select DEBUG_FS
+ help
+ This option provides tracing for the PREEMPT_RCU implementation,
+ permitting Makefile to trivially select kernel/rcupreempt_trace.c.
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff