arm64: KVM: Make PSCI_VERSION a fast path

For those CPUs that require PSCI to perform a BP invalidation,
going all the way to the PSCI code for not much is a waste of
precious cycles. Let's terminate that call as early as possible.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Marc Zyngier 2018-01-03 16:38:37 +00:00 committed by Catalin Marinas
parent 6840bdd73d
commit 90348689d5
1 changed files with 13 additions and 0 deletions

View File

@ -17,6 +17,7 @@
#include <linux/types.h> #include <linux/types.h>
#include <linux/jump_label.h> #include <linux/jump_label.h>
#include <uapi/linux/psci.h>
#include <asm/kvm_asm.h> #include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h> #include <asm/kvm_emulate.h>
@ -341,6 +342,18 @@ again:
if (exit_code == ARM_EXCEPTION_TRAP && !__populate_fault_info(vcpu)) if (exit_code == ARM_EXCEPTION_TRAP && !__populate_fault_info(vcpu))
goto again; goto again;
if (exit_code == ARM_EXCEPTION_TRAP &&
(kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_HVC64 ||
kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_HVC32) &&
vcpu_get_reg(vcpu, 0) == PSCI_0_2_FN_PSCI_VERSION) {
u64 val = PSCI_RET_NOT_SUPPORTED;
if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
val = 2;
vcpu_set_reg(vcpu, 0, val);
goto again;
}
if (static_branch_unlikely(&vgic_v2_cpuif_trap) && if (static_branch_unlikely(&vgic_v2_cpuif_trap) &&
exit_code == ARM_EXCEPTION_TRAP) { exit_code == ARM_EXCEPTION_TRAP) {
bool valid; bool valid;