path: root/arch/arm64/Kconfig
diff options
Diffstat (limited to 'arch/arm64/Kconfig')
1 files changed, 96 insertions, 0 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 2dc43c58923..19580615279 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -168,6 +168,102 @@ config SCHED_SMT
MultiThreading at a cost of slightly increased overhead in some
places. If unsure say N here.
+ bool "(EXPERIMENTAL) Disable CPU level scheduler load-balancing"
+ help
+ Disables scheduler load-balancing at CPU sched domain level.
+config SCHED_HMP
+ bool "(EXPERIMENTAL) Heterogenous multiprocessor scheduling"
+ help
+ Experimental scheduler optimizations for heterogeneous platforms.
+ Attempts to introspectively select task affinity to optimize power
+ and performance. Basic support for multiple (>2) cpu types is in place,
+ but it has only been tested with two types of cpus.
+ There is currently no support for migration of task groups, hence
+ !SCHED_AUTOGROUP. Furthermore, normal load-balancing must be disabled
+ between cpus of different type (DISABLE_CPU_SCHED_DOMAIN_BALANCE).
+ bool "(EXPERIMENTAL) Filter HMP migrations by task priority"
+ depends on SCHED_HMP
+ help
+ Enables task priority based HMP migration filter. Any task with
+ a NICE value above the threshold will always be on low-power cpus
+ with less compute capacity.
+ int "NICE priority threshold"
+ default 5
+ string "HMP scheduler fast CPU mask"
+ depends on SCHED_HMP
+ help
+ Leave empty to use device tree information.
+ Specify the cpuids of the fast CPUs in the system as a list string,
+ e.g. cpuid 0+1 should be specified as 0-1.
+ string "HMP scheduler slow CPU mask"
+ depends on SCHED_HMP
+ help
+ Leave empty to use device tree information.
+ Specify the cpuids of the slow CPUs in the system as a list string,
+ e.g. cpuid 0+1 should be specified as 0-1.
+ bool "Allows changing the load tracking scale through sysfs"
+ depends on SCHED_HMP
+ help
+ When turned on, this option exports the thresholds and load average
+ period value for the load tracking patches through sysfs.
+ The values can be modified to change the rate of load accumulation
+ and the thresholds used for HMP migration.
+ The load_avg_period_ms is the time in ms to reach a load average of
+ 0.5 for an idle task of 0 load average ratio that start a busy loop.
+ The up_threshold and down_threshold is the value to go to a faster
+ CPU or to go back to a slower cpu.
+ The {up,down}_threshold are devided by 1024 before being compared
+ to the load average.
+ For examples, with load_avg_period_ms = 128 and up_threshold = 512,
+ a running task with a load of 0 will be migrated to a bigger CPU after
+ 128ms, because after 128ms its load_avg_ratio is 0.5 and the real
+ up_threshold is 0.5.
+ This patch has the same behavior as changing the Y of the load
+ average computation to
+ (1002/1024)^(LOAD_AVG_PERIOD/load_avg_period_ms)
+ but it remove intermadiate overflows in computation.
+ bool "(EXPERIMENTAL) Frequency-Invariant Tracked Load for HMP"
+ help
+ Scales the current load contribution in line with the frequency
+ of the CPU that the task was executed on.
+ In this version, we use a simple linear scale derived from the
+ maximum frequency reported by CPUFreq.
+ Restricting tracked load to be scaled by the CPU's frequency
+ represents the consumption of possible compute capacity
+ (rather than consumption of actual instantaneous capacity as
+ normal) and allows the HMP migration's simple threshold
+ migration strategy to interact more predictably with CPUFreq's
+ asynchronous compute capacity changes.
+ bool "Small task packing for HMP"
+ depends on SCHED_HMP
+ default n
+ help
+ Allows the HMP Scheduler to pack small tasks into CPUs in the
+ smallest HMP domain.
+ Controlled by two sysfs files in sys/kernel/hmp.
+ packing_enable: 1 to enable, 0 to disable packing. Default 1.
+ packing_limit: runqueue load ratio where a RQ is considered
+ to be full. Default is NICE_0_LOAD * 9/8.
config NR_CPUS
int "Maximum number of CPUs (2-32)"
range 2 32