Commit ca3c34da authored by Marc Zyngier's avatar Marc Zyngier Committed by Oliver Upton
Browse files

KVM: arm64: GICv3: Handle in-LR deactivation when possible 



Even when we have either an LR overflow or SPIs in flight, it is
extremely likely that the interrupt being deactivated is still in
the LRs, and that going all the way back to the the generic trap
handling code is a waste of time.

Instead, try and deactivate in place when possible, and only if
this fails, perform a full exit.

Tested-by: default avatarFuad Tabba <tabba@google.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Tested-by: default avatarMark Brown <broonie@kernel.org>
Link: https://msgid.link/20251120172540.2267180-33-maz@kernel.org


Signed-off-by: default avatarOliver Upton <oupton@kernel.org>
parent 1c3b3cad

arch/arm64/kvm/hyp/vgic-v3-sr.c

+28 −10
Original line number Diff line number Diff line
@@ -792,7 +792,7 @@ static void __vgic_v3_bump_eoicount(void) 
	write_gicreg(hcr, ICH_HCR_EL2);

}



static void __vgic_v3_write_dir(struct kvm_vcpu *vcpu, u32 vmcr, int rt)

static int ___vgic_v3_write_dir(struct kvm_vcpu *vcpu, u32 vmcr, int rt)

{

	u32 vid = vcpu_get_reg(vcpu, rt);

	u64 lr_val;
@@ -800,19 +800,25 @@ static void __vgic_v3_write_dir(struct kvm_vcpu *vcpu, u32 vmcr, int rt) 


	/* EOImode == 0, nothing to be done here */

	if (!(vmcr & ICH_VMCR_EOIM_MASK))

		return;

		return 1;



	/* No deactivate to be performed on an LPI */

	if (vid >= VGIC_MIN_LPI)

		return;

		return 1;



	lr = __vgic_v3_find_active_lr(vcpu, vid, &lr_val);

	if (lr == -1) {

		__vgic_v3_bump_eoicount();

		return;

	if (lr != -1) {

		__vgic_v3_clear_active_lr(lr, lr_val);

		return 1;

	}



	__vgic_v3_clear_active_lr(lr, lr_val);

	return 0;

}



static void __vgic_v3_write_dir(struct kvm_vcpu *vcpu, u32 vmcr, int rt)

{

	if (!___vgic_v3_write_dir(vcpu, vmcr, rt))

		__vgic_v3_bump_eoicount();

}



static void __vgic_v3_write_eoir(struct kvm_vcpu *vcpu, u32 vmcr, int rt)
@@ -1247,9 +1253,21 @@ int __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu) 
	case SYS_ICC_DIR_EL1:

		if (unlikely(is_read))

			return 0;

		/* Full exit if required to handle overflow deactivation... */

		if (vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr & ICH_HCR_EL2_TDIR)

			return 0;

		/*

		 * Full exit if required to handle overflow deactivation,

		 * unless we can emulate it in the LRs (likely the majority

		 * of the cases).

		 */

		if (vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr & ICH_HCR_EL2_TDIR) {

			int ret;



			ret = ___vgic_v3_write_dir(vcpu, __vgic_v3_read_vmcr(),

						   kvm_vcpu_sys_get_rt(vcpu));

			if (ret)

				__kvm_skip_instr(vcpu);



			return ret;

		}

		fn = __vgic_v3_write_dir;

		break;

	case SYS_ICC_RPR_EL1: