Provide a config option to enable the steal_governor driver. Since the feature targets paravirtualized environments and requires SMP, enforce those dependencies. The driver selects CONFIG_PREFERRED_CPU for the core scheduler mechanisms to work.
It is recommended to build the driver as a module (m) instead of built-in (y) due to the following reasons: - Module parameters are read-only after initialization. Building as a module allows updating these parameters by simply reloading the module. Default module parameters cannot work in all configurations. - The driver can be completely disabled by unloading the module. - This feature works best when all VMs operate in a cooperative manner. Requiring an explicit module load ensures intentional deployment across all VMs by the system administrator. Suggested-by: Yury Norov <[email protected]> Signed-off-by: Shrikanth Hegde <[email protected]> --- drivers/virt/Kconfig | 18 ++++++++++++++++++ drivers/virt/Makefile | 1 + 2 files changed, 19 insertions(+) diff --git a/drivers/virt/Kconfig b/drivers/virt/Kconfig index 52eb7e4ba71f..6681d06363f9 100644 --- a/drivers/virt/Kconfig +++ b/drivers/virt/Kconfig @@ -41,6 +41,24 @@ config FSL_HV_MANAGER 4) A kernel interface for receiving callbacks when a managed partition shuts down. +config STEAL_GOVERNOR + tristate "Dynamic vCPU management based on steal time" + depends on PARAVIRT && SMP + select PREFERRED_CPU + default m + help + This driver helps to reduce the steal time in paravirtualized + environments, thereby reducing vCPU preemption. Reducing vCPU + preemption provides improved lock holder preemption and reduces + cost of vCPU preemption in the host. + + By default preferred CPUs will be same as active CPUs. Depending + on the steal time when steal_governor driver is enabled, + preferred CPUs could become subset of active CPUs. + + It is recommended to build it as module and load the module + to enable it. + source "drivers/virt/vboxguest/Kconfig" source "drivers/virt/nitro_enclaves/Kconfig" diff --git a/drivers/virt/Makefile b/drivers/virt/Makefile index f29901bd7820..05fb075ef5b8 100644 --- a/drivers/virt/Makefile +++ b/drivers/virt/Makefile @@ -5,6 +5,7 @@ obj-$(CONFIG_FSL_HV_MANAGER) += fsl_hypervisor.o obj-$(CONFIG_VMGENID) += vmgenid.o +obj-$(CONFIG_STEAL_GOVERNOR) += steal_governor.o obj-y += vboxguest/ obj-$(CONFIG_NITRO_ENCLAVES) += nitro_enclaves/ -- 2.47.3
