[v2,2/3] RISC-V: KVM: Update firmware counters for various events

Commit Message

Atish Patra Dec. 24, 2024, 9:04 p.m. UTC

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: Anup Patel <[e-mail]>
Signed-off-by: Atish Patra <[e-mail]>
---
 arch/riscv/kvm/vcpu_exit.c | 31 +++++++++++++++++++++++++++----
 1 file changed, 27 insertions(+), 4 deletions(-)

Patch

diff --git a/arch/riscv/kvm/vcpu_exit.c b/arch/riscv/kvm/vcpu_exit.c
index c9f8b2094554..acdcd619797e 100644
--- a/arch/riscv/kvm/vcpu_exit.c
+++ b/arch/riscv/kvm/vcpu_exit.c
@@ -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)