arm64: KVM: Add Kconfig option for max VCPUs per-Guest (da781470) · Commits · 戴 / test

Current max VCPUs per-Guest is set to 4 which is preventing us from creating a Guest (or VM) with 8 VCPUs on Host (e.g. X-Gene Storm SOC) with 8 Host CPUs. The correct value of max VCPUs per-Guest should be same as the max CPUs supported by GICv2 which is 8 but, increasing value of max VCPUs per-Guest can make things slower hence we add Kconfig option to let KVM users select appropriate max VCPUs per-Guest. Signed-off-by:

Anup Patel <anup.patel@linaro.org> Signed-off-by:

Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Signed-off-by:

Marc Zyngier <marc.zyngier@arm.com>

arch/arm64/include/asm/kvm_host.h

+6 −1

Original line number	Diff line number	Diff line
		@@ -26,7 +26,12 @@
		#include <asm/kvm_asm.h>
		#include <asm/kvm_mmio.h>

		#define KVM_MAX_VCPUS 4
		#if defined(CONFIG_KVM_ARM_MAX_VCPUS)
		#define KVM_MAX_VCPUS CONFIG_KVM_ARM_MAX_VCPUS
		#else
		#define KVM_MAX_VCPUS 0
		#endif

		#define KVM_USER_MEM_SLOTS 32
		#define KVM_PRIVATE_MEM_SLOTS 4
		#define KVM_COALESCED_MMIO_PAGE_OFFSET 1

arch/arm64/kvm/Kconfig

+11 −0

Original line number	Diff line number	Diff line
		@@ -36,6 +36,17 @@ config KVM_ARM_HOST
		---help---
		Provides host support for ARM processors.

		config KVM_ARM_MAX_VCPUS
		int "Number maximum supported virtual CPUs per VM"
		depends on KVM_ARM_HOST
		default 4
		help
		Static number of max supported virtual CPUs per VM.

		If you choose a high number, the vcpu structures will be quite
		large, so only choose a reasonable number that you expect to
		actually use.

		config KVM_ARM_VGIC
		bool
		depends on KVM_ARM_HOST && OF

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