From: marc.zyngier@arm.com (Marc Zyngier)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2 13/17] arm64: KVM: vgic-v3: Avoid accessing ICH registers
Date: Wed, 17 Feb 2016 16:40:45 +0000 [thread overview]
Message-ID: <1455727249-24752-14-git-send-email-marc.zyngier@arm.com> (raw)
In-Reply-To: <1455727249-24752-1-git-send-email-marc.zyngier@arm.com>
Just like on GICv2, we're a bit hammer-happy with GICv3, and access
them more often than we should.
Adopt a policy similar to what we do for GICv2, only save/restoring
the minimal set of registers. As we don't access the registers
linearly anymore (we may skip some), the convoluted accessors become
slightly simpler, and we can drop the ugly indexing macro that
tended to confuse the reviewers.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/kvm/hyp/vgic-v3-sr.c | 294 +++++++++++++++++++++++++---------------
include/kvm/arm_vgic.h | 6 -
virt/kvm/arm/vgic-v3.c | 4 +-
3 files changed, 183 insertions(+), 121 deletions(-)
diff --git a/arch/arm64/kvm/hyp/vgic-v3-sr.c b/arch/arm64/kvm/hyp/vgic-v3-sr.c
index 93f6c5c..b62c923 100644
--- a/arch/arm64/kvm/hyp/vgic-v3-sr.c
+++ b/arch/arm64/kvm/hyp/vgic-v3-sr.c
@@ -39,12 +39,104 @@
asm volatile("msr_s " __stringify(r) ", %0" : : "r" (__val));\
} while (0)
-/* vcpu is already in the HYP VA space */
+static u64 __hyp_text __gic_v3_get_lr(unsigned int lr)
+{
+ switch (lr & 0xf) {
+ case 0:
+ return read_gicreg(ICH_LR0_EL2);
+ case 1:
+ return read_gicreg(ICH_LR1_EL2);
+ case 2:
+ return read_gicreg(ICH_LR2_EL2);
+ case 3:
+ return read_gicreg(ICH_LR3_EL2);
+ case 4:
+ return read_gicreg(ICH_LR4_EL2);
+ case 5:
+ return read_gicreg(ICH_LR5_EL2);
+ case 6:
+ return read_gicreg(ICH_LR6_EL2);
+ case 7:
+ return read_gicreg(ICH_LR7_EL2);
+ case 8:
+ return read_gicreg(ICH_LR8_EL2);
+ case 9:
+ return read_gicreg(ICH_LR9_EL2);
+ case 10:
+ return read_gicreg(ICH_LR10_EL2);
+ case 11:
+ return read_gicreg(ICH_LR11_EL2);
+ case 12:
+ return read_gicreg(ICH_LR12_EL2);
+ case 13:
+ return read_gicreg(ICH_LR13_EL2);
+ case 14:
+ return read_gicreg(ICH_LR14_EL2);
+ case 15:
+ return read_gicreg(ICH_LR15_EL2);
+ }
+
+ unreachable();
+}
+
+static void __hyp_text __gic_v3_set_lr(u64 val, int lr)
+{
+ switch (lr & 0xf) {
+ case 0:
+ write_gicreg(val, ICH_LR0_EL2);
+ break;
+ case 1:
+ write_gicreg(val, ICH_LR1_EL2);
+ break;
+ case 2:
+ write_gicreg(val, ICH_LR2_EL2);
+ break;
+ case 3:
+ write_gicreg(val, ICH_LR3_EL2);
+ break;
+ case 4:
+ write_gicreg(val, ICH_LR4_EL2);
+ break;
+ case 5:
+ write_gicreg(val, ICH_LR5_EL2);
+ break;
+ case 6:
+ write_gicreg(val, ICH_LR6_EL2);
+ break;
+ case 7:
+ write_gicreg(val, ICH_LR7_EL2);
+ break;
+ case 8:
+ write_gicreg(val, ICH_LR8_EL2);
+ break;
+ case 9:
+ write_gicreg(val, ICH_LR9_EL2);
+ break;
+ case 10:
+ write_gicreg(val, ICH_LR10_EL2);
+ break;
+ case 11:
+ write_gicreg(val, ICH_LR11_EL2);
+ break;
+ case 12:
+ write_gicreg(val, ICH_LR12_EL2);
+ break;
+ case 13:
+ write_gicreg(val, ICH_LR13_EL2);
+ break;
+ case 14:
+ write_gicreg(val, ICH_LR14_EL2);
+ break;
+ case 15:
+ write_gicreg(val, ICH_LR15_EL2);
+ break;
+ }
+}
+
void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu)
{
struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
u64 val;
- u32 max_lr_idx, nr_pri_bits;
/*
* Make sure stores to the GIC via the memory mapped interface
@@ -53,68 +145,58 @@ void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu)
dsb(st);
cpu_if->vgic_vmcr = read_gicreg(ICH_VMCR_EL2);
- cpu_if->vgic_misr = read_gicreg(ICH_MISR_EL2);
- cpu_if->vgic_eisr = read_gicreg(ICH_EISR_EL2);
- cpu_if->vgic_elrsr = read_gicreg(ICH_ELSR_EL2);
- write_gicreg(0, ICH_HCR_EL2);
- val = read_gicreg(ICH_VTR_EL2);
- max_lr_idx = vtr_to_max_lr_idx(val);
- nr_pri_bits = vtr_to_nr_pri_bits(val);
+ if (vcpu->arch.vgic_cpu.live_lrs) {
+ int i;
+ u32 max_lr_idx, nr_pri_bits;
- switch (max_lr_idx) {
- case 15:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(15)] = read_gicreg(ICH_LR15_EL2);
- case 14:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(14)] = read_gicreg(ICH_LR14_EL2);
- case 13:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(13)] = read_gicreg(ICH_LR13_EL2);
- case 12:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(12)] = read_gicreg(ICH_LR12_EL2);
- case 11:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(11)] = read_gicreg(ICH_LR11_EL2);
- case 10:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(10)] = read_gicreg(ICH_LR10_EL2);
- case 9:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(9)] = read_gicreg(ICH_LR9_EL2);
- case 8:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(8)] = read_gicreg(ICH_LR8_EL2);
- case 7:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(7)] = read_gicreg(ICH_LR7_EL2);
- case 6:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(6)] = read_gicreg(ICH_LR6_EL2);
- case 5:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(5)] = read_gicreg(ICH_LR5_EL2);
- case 4:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(4)] = read_gicreg(ICH_LR4_EL2);
- case 3:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(3)] = read_gicreg(ICH_LR3_EL2);
- case 2:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(2)] = read_gicreg(ICH_LR2_EL2);
- case 1:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(1)] = read_gicreg(ICH_LR1_EL2);
- case 0:
- cpu_if->vgic_lr[VGIC_V3_LR_INDEX(0)] = read_gicreg(ICH_LR0_EL2);
- }
+ cpu_if->vgic_misr = read_gicreg(ICH_MISR_EL2);
+ cpu_if->vgic_eisr = read_gicreg(ICH_EISR_EL2);
+ cpu_if->vgic_elrsr = read_gicreg(ICH_ELSR_EL2);
- switch (nr_pri_bits) {
- case 7:
- cpu_if->vgic_ap0r[3] = read_gicreg(ICH_AP0R3_EL2);
- cpu_if->vgic_ap0r[2] = read_gicreg(ICH_AP0R2_EL2);
- case 6:
- cpu_if->vgic_ap0r[1] = read_gicreg(ICH_AP0R1_EL2);
- default:
- cpu_if->vgic_ap0r[0] = read_gicreg(ICH_AP0R0_EL2);
- }
+ write_gicreg(0, ICH_HCR_EL2);
+ val = read_gicreg(ICH_VTR_EL2);
+ max_lr_idx = vtr_to_max_lr_idx(val);
+ nr_pri_bits = vtr_to_nr_pri_bits(val);
- switch (nr_pri_bits) {
- case 7:
- cpu_if->vgic_ap1r[3] = read_gicreg(ICH_AP1R3_EL2);
- cpu_if->vgic_ap1r[2] = read_gicreg(ICH_AP1R2_EL2);
- case 6:
- cpu_if->vgic_ap1r[1] = read_gicreg(ICH_AP1R1_EL2);
- default:
- cpu_if->vgic_ap1r[0] = read_gicreg(ICH_AP1R0_EL2);
+ for (i = 0; i <= max_lr_idx; i++) {
+ if (vcpu->arch.vgic_cpu.live_lrs & (1UL << i))
+ cpu_if->vgic_lr[i] = __gic_v3_get_lr(i);
+ }
+
+ switch (nr_pri_bits) {
+ case 7:
+ cpu_if->vgic_ap0r[3] = read_gicreg(ICH_AP0R3_EL2);
+ cpu_if->vgic_ap0r[2] = read_gicreg(ICH_AP0R2_EL2);
+ case 6:
+ cpu_if->vgic_ap0r[1] = read_gicreg(ICH_AP0R1_EL2);
+ default:
+ cpu_if->vgic_ap0r[0] = read_gicreg(ICH_AP0R0_EL2);
+ }
+
+ switch (nr_pri_bits) {
+ case 7:
+ cpu_if->vgic_ap1r[3] = read_gicreg(ICH_AP1R3_EL2);
+ cpu_if->vgic_ap1r[2] = read_gicreg(ICH_AP1R2_EL2);
+ case 6:
+ cpu_if->vgic_ap1r[1] = read_gicreg(ICH_AP1R1_EL2);
+ default:
+ cpu_if->vgic_ap1r[0] = read_gicreg(ICH_AP1R0_EL2);
+ }
+
+ vcpu->arch.vgic_cpu.live_lrs = 0;
+ } else {
+ cpu_if->vgic_misr = 0;
+ cpu_if->vgic_eisr = 0;
+ cpu_if->vgic_elrsr = 0xffff;
+ cpu_if->vgic_ap0r[0] = 0;
+ cpu_if->vgic_ap0r[1] = 0;
+ cpu_if->vgic_ap0r[2] = 0;
+ cpu_if->vgic_ap0r[3] = 0;
+ cpu_if->vgic_ap1r[0] = 0;
+ cpu_if->vgic_ap1r[1] = 0;
+ cpu_if->vgic_ap1r[2] = 0;
+ cpu_if->vgic_ap1r[3] = 0;
}
val = read_gicreg(ICC_SRE_EL2);
@@ -128,6 +210,8 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu)
struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
u64 val;
u32 max_lr_idx, nr_pri_bits;
+ u16 live_lrs = 0;
+ int i;
/*
* VFIQEn is RES1 if ICC_SRE_EL1.SRE is 1. This causes a
@@ -140,68 +224,51 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu)
write_gicreg(cpu_if->vgic_sre, ICC_SRE_EL1);
isb();
- write_gicreg(cpu_if->vgic_hcr, ICH_HCR_EL2);
- write_gicreg(cpu_if->vgic_vmcr, ICH_VMCR_EL2);
-
val = read_gicreg(ICH_VTR_EL2);
max_lr_idx = vtr_to_max_lr_idx(val);
nr_pri_bits = vtr_to_nr_pri_bits(val);
- switch (nr_pri_bits) {
- case 7:
- write_gicreg(cpu_if->vgic_ap0r[3], ICH_AP0R3_EL2);
- write_gicreg(cpu_if->vgic_ap0r[2], ICH_AP0R2_EL2);
- case 6:
- write_gicreg(cpu_if->vgic_ap0r[1], ICH_AP0R1_EL2);
- default:
- write_gicreg(cpu_if->vgic_ap0r[0], ICH_AP0R0_EL2);
+ for (i = 0; i <= max_lr_idx; i++) {
+ if (cpu_if->vgic_lr[i] & ICH_LR_STATE)
+ live_lrs |= (1 << i);
}
- switch (nr_pri_bits) {
- case 7:
- write_gicreg(cpu_if->vgic_ap1r[3], ICH_AP1R3_EL2);
- write_gicreg(cpu_if->vgic_ap1r[2], ICH_AP1R2_EL2);
- case 6:
- write_gicreg(cpu_if->vgic_ap1r[1], ICH_AP1R1_EL2);
- default:
- write_gicreg(cpu_if->vgic_ap1r[0], ICH_AP1R0_EL2);
- }
+ write_gicreg(cpu_if->vgic_vmcr, ICH_VMCR_EL2);
+
+ if (live_lrs) {
+ write_gicreg(cpu_if->vgic_hcr, ICH_HCR_EL2);
+
+ switch (nr_pri_bits) {
+ case 7:
+ write_gicreg(cpu_if->vgic_ap0r[3], ICH_AP0R3_EL2);
+ write_gicreg(cpu_if->vgic_ap0r[2], ICH_AP0R2_EL2);
+ case 6:
+ write_gicreg(cpu_if->vgic_ap0r[1], ICH_AP0R1_EL2);
+ default:
+ write_gicreg(cpu_if->vgic_ap0r[0], ICH_AP0R0_EL2);
+ }
+
+ switch (nr_pri_bits) {
+ case 7:
+ write_gicreg(cpu_if->vgic_ap1r[3], ICH_AP1R3_EL2);
+ write_gicreg(cpu_if->vgic_ap1r[2], ICH_AP1R2_EL2);
+ case 6:
+ write_gicreg(cpu_if->vgic_ap1r[1], ICH_AP1R1_EL2);
+ default:
+ write_gicreg(cpu_if->vgic_ap1r[0], ICH_AP1R0_EL2);
+ }
- switch (max_lr_idx) {
- case 15:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(15)], ICH_LR15_EL2);
- case 14:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(14)], ICH_LR14_EL2);
- case 13:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(13)], ICH_LR13_EL2);
- case 12:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(12)], ICH_LR12_EL2);
- case 11:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(11)], ICH_LR11_EL2);
- case 10:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(10)], ICH_LR10_EL2);
- case 9:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(9)], ICH_LR9_EL2);
- case 8:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(8)], ICH_LR8_EL2);
- case 7:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(7)], ICH_LR7_EL2);
- case 6:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(6)], ICH_LR6_EL2);
- case 5:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(5)], ICH_LR5_EL2);
- case 4:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(4)], ICH_LR4_EL2);
- case 3:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(3)], ICH_LR3_EL2);
- case 2:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(2)], ICH_LR2_EL2);
- case 1:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(1)], ICH_LR1_EL2);
- case 0:
- write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(0)], ICH_LR0_EL2);
+ for (i = 0; i <= max_lr_idx; i++) {
+ val = 0;
+
+ if (live_lrs & (1 << i))
+ val = cpu_if->vgic_lr[i];
+
+ __gic_v3_set_lr(val, i);
+ }
}
+
/*
* Ensures that the above will have reached the
* (re)distributors. This ensure the guest will read the
@@ -209,6 +276,7 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu)
*/
isb();
dsb(sy);
+ vcpu->arch.vgic_cpu.live_lrs = live_lrs;
/*
* Prevent the guest from touching the GIC system registers if
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index f473fd6..281caf8 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -279,12 +279,6 @@ struct vgic_v2_cpu_if {
u32 vgic_lr[VGIC_V2_MAX_LRS];
};
-/*
- * LRs are stored in reverse order in memory. make sure we index them
- * correctly.
- */
-#define VGIC_V3_LR_INDEX(lr) (VGIC_V3_MAX_LRS - 1 - lr)
-
struct vgic_v3_cpu_if {
#ifdef CONFIG_KVM_ARM_VGIC_V3
u32 vgic_hcr;
diff --git a/virt/kvm/arm/vgic-v3.c b/virt/kvm/arm/vgic-v3.c
index 453eafd..11b5ff6 100644
--- a/virt/kvm/arm/vgic-v3.c
+++ b/virt/kvm/arm/vgic-v3.c
@@ -42,7 +42,7 @@ static u32 ich_vtr_el2;
static struct vgic_lr vgic_v3_get_lr(const struct kvm_vcpu *vcpu, int lr)
{
struct vgic_lr lr_desc;
- u64 val = vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[VGIC_V3_LR_INDEX(lr)];
+ u64 val = vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr];
if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
lr_desc.irq = val & ICH_LR_VIRTUALID_MASK;
@@ -106,7 +106,7 @@ static void vgic_v3_set_lr(struct kvm_vcpu *vcpu, int lr,
lr_val |= ((u64)lr_desc.hwirq) << ICH_LR_PHYS_ID_SHIFT;
}
- vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[VGIC_V3_LR_INDEX(lr)] = lr_val;
+ vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = lr_val;
if (!(lr_desc.state & LR_STATE_MASK))
vcpu->arch.vgic_cpu.vgic_v3.vgic_elrsr |= (1U << lr);
--
2.1.4
next prev parent reply other threads:[~2016-02-17 16:40 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-17 16:40 [PATCH v2 00/17] KVM/ARM: Guest Entry/Exit optimizations Marc Zyngier
2016-02-17 16:40 ` [PATCH v2 01/17] arm64: KVM: Switch the sys_reg search to be a binary search Marc Zyngier
2016-02-17 16:40 ` [PATCH v2 02/17] ARM: KVM: Properly sort the invariant table Marc Zyngier
2016-02-17 16:40 ` [PATCH v2 03/17] ARM: KVM: Enforce sorting of all CP tables Marc Zyngier
2016-02-17 16:40 ` [PATCH v2 04/17] ARM: KVM: Rename struct coproc_reg::is_64 to is_64bit Marc Zyngier
2016-02-17 16:40 ` [PATCH v2 05/17] ARM: KVM: Switch the CP reg search to be a binary search Marc Zyngier
2016-02-17 16:40 ` [PATCH v2 06/17] KVM: arm/arm64: timer: Add active state caching Marc Zyngier
2016-02-17 16:40 ` [PATCH v2 07/17] arm64: KVM: vgic-v2: Avoid accessing GICH registers Marc Zyngier
2016-03-02 23:08 ` Christoffer Dall
2016-02-17 16:40 ` [PATCH v2 08/17] arm64: KVM: vgic-v2: Save maintenance interrupt state only if required Marc Zyngier
2016-03-02 23:08 ` Christoffer Dall
2016-03-03 8:28 ` Marc Zyngier
2016-02-17 16:40 ` [PATCH v2 09/17] arm64: KVM: vgic-v2: Move GICH_ELRSR saving to its own function Marc Zyngier
2016-03-02 23:08 ` Christoffer Dall
2016-02-17 16:40 ` [PATCH v2 10/17] arm64: KVM: vgic-v2: Do not save an LR known to be empty Marc Zyngier
2016-03-02 23:08 ` Christoffer Dall
2016-02-17 16:40 ` [PATCH v2 11/17] arm64: KVM: vgic-v2: Only wipe LRs on vcpu exit Marc Zyngier
2016-03-02 23:08 ` Christoffer Dall
2016-03-03 8:14 ` Marc Zyngier
2016-03-03 15:58 ` Marc Zyngier
2016-03-04 11:36 ` Christoffer Dall
2016-03-04 11:45 ` Marc Zyngier
2016-02-17 16:40 ` [PATCH v2 12/17] arm64: KVM: vgic-v2: Make GICD_SGIR quicker to hit Marc Zyngier
2016-03-02 23:08 ` Christoffer Dall
2016-02-17 16:40 ` Marc Zyngier [this message]
2016-02-17 16:40 ` [PATCH v2 14/17] arm64: KVM: vgic-v3: Save maintenance interrupt state only if required Marc Zyngier
2016-03-03 19:21 ` Christoffer Dall
2016-02-17 16:40 ` [PATCH v2 15/17] arm64: KVM: vgic-v3: Do not save an LR known to be empty Marc Zyngier
2016-03-03 19:21 ` Christoffer Dall
2016-02-17 16:40 ` [PATCH v2 16/17] arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit Marc Zyngier
2016-03-03 19:21 ` Christoffer Dall
2016-02-17 16:40 ` [PATCH v2 17/17] arm64: KVM: vgic-v3: Do not save ICH_AP0Rn_EL2 for GICv2 emulation Marc Zyngier
2016-03-03 19:21 ` Christoffer Dall
2016-03-04 8:54 ` Marc Zyngier
2016-02-29 0:57 ` [PATCH v2 00/17] KVM/ARM: Guest Entry/Exit optimizations Mihai Claudiu Caraman
2016-02-29 8:26 ` Marc Zyngier
2016-02-29 10:43 ` Mihai Claudiu Caraman
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