Commit 2f15b5ea authored by Atish Patra's avatar Atish Patra Committed by Anup Patel
Browse files

RISC-V: KVM: Update firmware counters for various events 



SBI PMU specification defines few firmware counters which can be
used by the guests to collect the statstics about various traps
occurred in the host.

Update these counters whenever a corresponding trap is taken

Reviewed-by: default avatarAnup Patel <anup@brainfault.org>
Signed-off-by: default avatarAtish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20241224-kvm_guest_stat-v2-2-08a77ac36b02@rivosinc.com


Signed-off-by: default avatarAnup Patel <anup@brainfault.org>
parent 51c58956

arch/riscv/kvm/vcpu_exit.c

+27 −4
Original line number Diff line number Diff line
@@ -165,6 +165,17 @@ void kvm_riscv_vcpu_trap_redirect(struct kvm_vcpu *vcpu, 
	vcpu->arch.guest_context.sstatus |= SR_SPP;

}



static inline int vcpu_redirect(struct kvm_vcpu *vcpu, struct kvm_cpu_trap *trap)

{

	int ret = -EFAULT;



	if (vcpu->arch.guest_context.hstatus & HSTATUS_SPV) {

		kvm_riscv_vcpu_trap_redirect(vcpu, trap);

		ret = 1;

	}

	return ret;

}



/*

 * Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on

 * proper exit to userspace.
@@ -183,15 +194,27 @@ int kvm_riscv_vcpu_exit(struct kvm_vcpu *vcpu, struct kvm_run *run, 
	run->exit_reason = KVM_EXIT_UNKNOWN;

	switch (trap->scause) {

	case EXC_INST_ILLEGAL:

		kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_ILLEGAL_INSN);

		ret = vcpu_redirect(vcpu, trap);

		break;

	case EXC_LOAD_MISALIGNED:

		kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_MISALIGNED_LOAD);

		ret = vcpu_redirect(vcpu, trap);

		break;

	case EXC_STORE_MISALIGNED:

		kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_MISALIGNED_STORE);

		ret = vcpu_redirect(vcpu, trap);

		break;

	case EXC_LOAD_ACCESS:

		kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_ACCESS_LOAD);

		ret = vcpu_redirect(vcpu, trap);

		break;

	case EXC_STORE_ACCESS:

		kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_ACCESS_STORE);

		ret = vcpu_redirect(vcpu, trap);

		break;

	case EXC_INST_ACCESS:

		if (vcpu->arch.guest_context.hstatus & HSTATUS_SPV) {

			kvm_riscv_vcpu_trap_redirect(vcpu, trap);

			ret = 1;

		}

		ret = vcpu_redirect(vcpu, trap);

		break;

	case EXC_VIRTUAL_INST_FAULT:

		if (vcpu->arch.guest_context.hstatus & HSTATUS_SPV)