This option enables preemptible-RCU code that is common between
the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations.
+config CONTEXT_TRACKING
+ bool
+
config RCU_USER_QS
bool "Consider userspace as in RCU extended quiescent state"
- depends on HAVE_RCU_USER_QS && SMP
+ depends on HAVE_CONTEXT_TRACKING && SMP
+ select CONTEXT_TRACKING
help
This option sets hooks on kernel / userspace boundaries and
puts RCU in extended quiescent state when the CPU runs in
userspace. It means that when a CPU runs in userspace, it is
excluded from the global RCU state machine and thus doesn't
- to keep the timer tick on for RCU.
+ try to keep the timer tick on for RCU.
Unless you want to hack and help the development of the full
- tickless feature, you shouldn't enable this option. It adds
- unnecessary overhead.
+ dynticks mode, you shouldn't enable this option. It also
+ adds unnecessary overhead.
If unsure say N
-config RCU_USER_QS_FORCE
- bool "Force userspace extended QS by default"
- depends on RCU_USER_QS
+config CONTEXT_TRACKING_FORCE
+ bool "Force context tracking"
+ depends on CONTEXT_TRACKING
help
- Set the hooks in user/kernel boundaries by default in order to
- test this feature that treats userspace as an extended quiescent
- state until we have a real user like a full adaptive nohz option.
-
- Unless you want to hack and help the development of the full
- tickless feature, you shouldn't enable this option. It adds
- unnecessary overhead.
-
- If unsure say N
+ Probe on user/kernel boundaries by default in order to
+ test the features that rely on it such as userspace RCU extended
+ quiescent states.
+ This test is there for debugging until we have a real user like the
+ full dynticks mode.
config RCU_FANOUT
int "Tree-based hierarchical RCU fanout value"
depends on NO_HZ && SMP
default n
help
- This option causes RCU to attempt to accelerate grace periods
- in order to allow CPUs to enter dynticks-idle state more
- quickly. On the other hand, this option increases the overhead
- of the dynticks-idle checking, particularly on systems with
- large numbers of CPUs.
+ This option causes RCU to attempt to accelerate grace periods in
+ order to allow CPUs to enter dynticks-idle state more quickly.
+ On the other hand, this option increases the overhead of the
+ dynticks-idle checking, thus degrading scheduling latency.
- Say Y if energy efficiency is critically important, particularly
- if you have relatively few CPUs.
+ Say Y if energy efficiency is critically important, and you don't
+ care about real-time response.
Say N if you are unsure.
Accept the default if unsure.
+config RCU_NOCB_CPU
+ bool "Offload RCU callback processing from boot-selected CPUs"
+ depends on TREE_RCU || TREE_PREEMPT_RCU
+ default n
+ help
+ Use this option to reduce OS jitter for aggressive HPC or
+ real-time workloads. It can also be used to offload RCU
+ callback invocation to energy-efficient CPUs in battery-powered
+ asymmetric multiprocessors.
+
+ This option offloads callback invocation from the set of
+ CPUs specified at boot time by the rcu_nocbs parameter.
+ For each such CPU, a kthread ("rcuoN") will be created to
+ invoke callbacks, where the "N" is the CPU being offloaded.
+ Nothing prevents this kthread from running on the specified
+ CPUs, but (1) the kthreads may be preempted between each
+ callback, and (2) affinity or cgroups can be used to force
+ the kthreads to run on whatever set of CPUs is desired.
+
+ Say Y here if you want reduced OS jitter on selected CPUs.
+ Say N here if you are unsure.
+
endmenu # "RCU Subsystem"
config IKCONFIG
config HAVE_UNSTABLE_SCHED_CLOCK
bool
+#
+# For architectures that want to enable the support for NUMA-affine scheduler
+# balancing logic:
+#
+config ARCH_SUPPORTS_NUMA_BALANCING
+ bool
+
+# For architectures that (ab)use NUMA to represent different memory regions
+# all cpu-local but of different latencies, such as SuperH.
+#
+config ARCH_WANT_NUMA_VARIABLE_LOCALITY
+ bool
+
+#
+# For architectures that are willing to define _PAGE_NUMA as _PAGE_PROTNONE
+config ARCH_WANTS_PROT_NUMA_PROT_NONE
+ bool
+
+config ARCH_USES_NUMA_PROT_NONE
+ bool
+ default y
+ depends on ARCH_WANTS_PROT_NUMA_PROT_NONE
+ depends on NUMA_BALANCING
+
+config NUMA_BALANCING_DEFAULT_ENABLED
+ bool "Automatically enable NUMA aware memory/task placement"
+ default y
+ depends on NUMA_BALANCING
+ help
+ If set, autonumic 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
+ depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY
+ depends on SMP && NUMA && MIGRATION
+ help
+ This option adds support for automatic NUMA aware memory/task placement.
+ The mechanism is quite primitive and is based on migrating memory when
+ it is references to the node the task is running on.
+
+ This system will be inactive on UMA systems.
+
menuconfig CGROUPS
boolean "Control Group support"
depends on EVENTFD
config MEMCG_KMEM
bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
depends on MEMCG && EXPERIMENTAL
- default n
+ depends on SLUB || SLAB
help
The Kernel Memory extension for Memory Resource Controller can limit
the amount of memory used by kernel objects in the system. Those are
# Filesystems
depends on 9P_FS = n
depends on AFS_FS = n
- depends on AUTOFS4_FS = n
depends on CEPH_FS = n
depends on CIFS = n
depends on CODA_FS = n
- depends on FUSE_FS = n
depends on GFS2_FS = n
depends on NCP_FS = n
depends on NFSD = n
Enabling this option will pass "-Os" instead of "-O2" to gcc
resulting in a smaller kernel.
- If unsure, say Y.
+ If unsure, say N.
config SYSCTL
bool
projects / GitHub / mt8127 / android_kernel_alcatel_ttab.git / blobdiff