thousands of CPUs. It also scales down nicely to
smaller systems.
-config TREE_PREEMPT_RCU
+config PREEMPT_RCU
bool "Preemptible tree-based hierarchical RCU"
depends on PREEMPT
select IRQ_WORK
endchoice
-config PREEMPT_RCU
- def_bool TREE_PREEMPT_RCU
- help
- This option enables preemptible-RCU code that is common between
- TREE_PREEMPT_RCU and, in the old days, TINY_PREEMPT_RCU.
-
config TASKS_RCU
bool "Task_based RCU implementation using voluntary context switch"
default n
If unsure, say N.
config RCU_STALL_COMMON
- def_bool ( TREE_RCU || TREE_PREEMPT_RCU || RCU_TRACE )
+ def_bool ( TREE_RCU || PREEMPT_RCU || RCU_TRACE )
help
This option enables RCU CPU stall code that is common between
the TINY and TREE variants of RCU. The purpose is to allow
int "Tree-based hierarchical RCU fanout value"
range 2 64 if 64BIT
range 2 32 if !64BIT
- depends on TREE_RCU || TREE_PREEMPT_RCU
+ depends on TREE_RCU || PREEMPT_RCU
default 64 if 64BIT
default 32 if !64BIT
help
int "Tree-based hierarchical RCU leaf-level fanout value"
range 2 RCU_FANOUT if 64BIT
range 2 RCU_FANOUT if !64BIT
- depends on TREE_RCU || TREE_PREEMPT_RCU
+ depends on TREE_RCU || PREEMPT_RCU
default 16
help
This option controls the leaf-level fanout of hierarchical
config RCU_FANOUT_EXACT
bool "Disable tree-based hierarchical RCU auto-balancing"
- depends on TREE_RCU || TREE_PREEMPT_RCU
+ depends on TREE_RCU || PREEMPT_RCU
default n
help
This option forces use of the exact RCU_FANOUT value specified,
Say N if you are unsure.
config TREE_RCU_TRACE
- def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
+ def_bool RCU_TRACE && ( TREE_RCU || PREEMPT_RCU )
select DEBUG_FS
help
This option provides tracing for the TREE_RCU and
- TREE_PREEMPT_RCU implementations, permitting Makefile to
+ PREEMPT_RCU implementations, permitting Makefile to
trivially select kernel/rcutree_trace.c.
config RCU_BOOST
Say Y here if you are working with real-time apps or heavy loads
Say N here if you are unsure.
-config RCU_BOOST_PRIO
- int "Real-time priority to boost RCU readers to"
+config RCU_KTHREAD_PRIO
+ int "Real-time priority to use for RCU worker threads"
range 1 99
depends on RCU_BOOST
default 1
help
- This option specifies the real-time priority to which long-term
- preempted RCU readers are to be boosted. If you are working
- with a real-time application that has one or more CPU-bound
- threads running at a real-time priority level, you should set
- RCU_BOOST_PRIO to a priority higher then the highest-priority
- real-time CPU-bound thread. The default RCU_BOOST_PRIO value
- of 1 is appropriate in the common case, which is real-time
+ This option specifies the SCHED_FIFO priority value that will be
+ assigned to the rcuc/n and rcub/n threads and is also the value
+ used for RCU_BOOST (if enabled). If you are working with a
+ real-time application that has one or more CPU-bound threads
+ running at a real-time priority level, you should set
+ RCU_KTHREAD_PRIO to a priority higher than the highest-priority
+ real-time CPU-bound application thread. The default RCU_KTHREAD_PRIO
+ value of 1 is appropriate in the common case, which is real-time
applications that do not have any CPU-bound threads.
Some real-time applications might not have a single real-time
thread that saturates a given CPU, but instead might have
multiple real-time threads that, taken together, fully utilize
- that CPU. In this case, you should set RCU_BOOST_PRIO to
+ that CPU. In this case, you should set RCU_KTHREAD_PRIO to
a priority higher than the lowest-priority thread that is
conspiring to prevent the CPU from running any non-real-time
tasks. For example, if one thread at priority 10 and another
thread at priority 5 are between themselves fully consuming
- the CPU time on a given CPU, then RCU_BOOST_PRIO should be
+ the CPU time on a given CPU, then RCU_KTHREAD_PRIO should be
set to priority 6 or higher.
Specify the real-time priority, or take the default if unsure.
config RCU_NOCB_CPU
bool "Offload RCU callback processing from boot-selected CPUs"
- depends on TREE_RCU || TREE_PREEMPT_RCU
+ depends on TREE_RCU || PREEMPT_RCU
default n
help
Use this option to reduce OS jitter for aggressive HPC or
choice
prompt "Build-forced no-CBs CPUs"
default RCU_NOCB_CPU_NONE
+ depends on RCU_NOCB_CPU
help
This option allows no-CBs CPUs (whose RCU callbacks are invoked
from kthreads rather than from softirq context) to be specified
config RCU_NOCB_CPU_NONE
bool "No build_forced no-CBs CPUs"
- depends on RCU_NOCB_CPU
help
This option does not force any of the CPUs to be no-CBs CPUs.
Only CPUs designated by the rcu_nocbs= boot parameter will be
config RCU_NOCB_CPU_ZERO
bool "CPU 0 is a build_forced no-CBs CPU"
- depends on RCU_NOCB_CPU
help
This option forces CPU 0 to be a no-CBs CPU, so that its RCU
callbacks are invoked by a per-CPU kthread whose name begins
config RCU_NOCB_CPU_ALL
bool "All CPUs are build_forced no-CBs CPUs"
- depends on RCU_NOCB_CPU
help
This option forces all CPUs to be no-CBs CPUs. The rcu_nocbs=
boot parameter will be ignored. All CPUs' RCU callbacks will
config ARCH_WANT_NUMA_VARIABLE_LOCALITY
bool
-config NUMA_BALANCING_DEFAULT_ENABLED
- bool "Automatically enable NUMA aware memory/task placement"
- default y
- depends on NUMA_BALANCING
- help
- If set, automatic NUMA balancing will be enabled if running on a NUMA
- machine.
-
config NUMA_BALANCING
bool "Memory placement aware NUMA scheduler"
depends on ARCH_SUPPORTS_NUMA_BALANCING
This system will be inactive on UMA systems.
+config NUMA_BALANCING_DEFAULT_ENABLED
+ bool "Automatically enable NUMA aware memory/task placement"
+ default y
+ depends on NUMA_BALANCING
+ help
+ If set, automatic NUMA balancing will be enabled if running on a NUMA
+ machine.
+
menuconfig CGROUPS
boolean "Control Group support"
select KERNFS
Provides a simple Resource Controller for monitoring the
total CPU consumed by the tasks in a cgroup.
-config RESOURCE_COUNTERS
- bool "Resource counters"
- help
- This option enables controller independent resource accounting
- infrastructure that works with cgroups.
+config PAGE_COUNTER
+ bool
config MEMCG
bool "Memory Resource Controller for Control Groups"
- depends on RESOURCE_COUNTERS
+ select PAGE_COUNTER
select EVENTFD
help
Provides a memory resource controller that manages both anonymous
memory and page cache. (See Documentation/cgroups/memory.txt)
- Note that setting this option increases fixed memory overhead
- associated with each page of memory in the system. By this,
- 8(16)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. 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 controller)
-
config MEMCG_SWAP
bool "Memory Resource Controller Swap Extension"
depends on MEMCG && SWAP
config CGROUP_HUGETLB
bool "HugeTLB Resource Controller for Control Groups"
- depends on RESOURCE_COUNTERS && HUGETLB_PAGE
+ depends on HUGETLB_PAGE
+ select PAGE_COUNTER
default n
help
Provides a cgroup Resource Controller for HugeTLB pages.
endif
+config INIT_FALLBACK
+ bool "Fall back to defaults if init= parameter is bad"
+ default y
+ help
+ If enabled, the kernel will try the default init binaries if an
+ explicit request from the init= parameter fails.
+
+ This can have unexpected effects. For example, booting
+ with init=/sbin/kiosk_app will run /sbin/init or even /bin/sh
+ if /sbin/kiosk_app cannot be executed.
+
+ The default value of Y is consistent with historical behavior.
+ Selecting N is likely to be more appropriate for most uses,
+ especially on kiosks and on kernels that are intended to be
+ run under the control of a script.
+
config CC_OPTIMIZE_FOR_SIZE
bool "Optimize for size"
help