[PATCH 09/37] KVM: arm64: Move debug dirty flag calculation out of world switch

Christoffer Dall christoffer.dall at linaro.org
Thu Oct 12 03:41:13 PDT 2017


There is no need to figure out inside the world-switch if we should
save/restore the debug registers or not, we can might as well do that in
the higher level debug setup code, making it easier to optimize down the
line.

Signed-off-by: Christoffer Dall <christoffer.dall at linaro.org>
---
 arch/arm64/kvm/debug.c        | 9 +++++++++
 arch/arm64/kvm/hyp/debug-sr.c | 6 ------
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c
index dbadfaf..62550de19 100644
--- a/arch/arm64/kvm/debug.c
+++ b/arch/arm64/kvm/debug.c
@@ -193,6 +193,15 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu)
 	if (trap_debug)
 		vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA;
 
+	/*
+	 * If any of KDE, MDE or KVM_ARM64_DEBUG_DIRTY is set, perform
+	 * a full save/restore cycle.
+	 */
+	if ((vcpu_sys_reg(vcpu, MDSCR_EL1) & DBG_MDSCR_KDE) ||
+	    (vcpu_sys_reg(vcpu, MDSCR_EL1) & DBG_MDSCR_MDE))
+		vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY;
+
+
 	trace_kvm_arm_set_dreg32("MDCR_EL2", vcpu->arch.mdcr_el2);
 	trace_kvm_arm_set_dreg32("MDSCR_EL1", vcpu_sys_reg(vcpu, MDSCR_EL1));
 }
diff --git a/arch/arm64/kvm/hyp/debug-sr.c b/arch/arm64/kvm/hyp/debug-sr.c
index f5154ed..0fc0758 100644
--- a/arch/arm64/kvm/hyp/debug-sr.c
+++ b/arch/arm64/kvm/hyp/debug-sr.c
@@ -172,12 +172,6 @@ void __hyp_text __debug_restore_state(struct kvm_vcpu *vcpu,
 
 void __hyp_text __debug_cond_save_host_state(struct kvm_vcpu *vcpu)
 {
-	/* If any of KDE, MDE or KVM_ARM64_DEBUG_DIRTY is set, perform
-	 * a full save/restore cycle. */
-	if ((vcpu->arch.ctxt.sys_regs[MDSCR_EL1] & DBG_MDSCR_KDE) ||
-	    (vcpu->arch.ctxt.sys_regs[MDSCR_EL1] & DBG_MDSCR_MDE))
-		vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY;
-
 	__debug_save_state(vcpu, &vcpu->arch.host_debug_state.regs,
 			   kern_hyp_va(vcpu->arch.host_cpu_context));
 	__debug_save_spe()(&vcpu->arch.host_debug_state.pmscr_el1);
-- 
2.9.0




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