[PATCH v12 09/21] KVM: ARM64: Add access handler for event counter register
Shannon Zhao
zhaoshenglong at huawei.com
Mon Feb 22 01:37:45 PST 2016
From: Shannon Zhao <shannon.zhao at linaro.org>
These kind of registers include PMEVCNTRn, PMCCNTR and PMXEVCNTR which
is mapped to PMEVCNTRn.
The access handler translates all aarch32 register offsets to aarch64
ones and uses vcpu_sys_reg() to access their values to avoid taking care
of big endian.
When reading these registers, return the sum of register value and the
value perf event counts.
Signed-off-by: Shannon Zhao <shannon.zhao at linaro.org>
Reviewed-by: Andrew Jones <drjones at redhat.com>
---
arch/arm64/kvm/sys_regs.c | 125 ++++++++++++++++++++++++++++++++++++++++++++--
include/kvm/arm_pmu.h | 3 ++
virt/kvm/arm/pmu.c | 15 ++++++
3 files changed, 139 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 7c6212a..70a47a9 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -561,6 +561,44 @@ static bool access_pmu_evtyper(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
return true;
}
+static bool access_pmu_evcntr(struct kvm_vcpu *vcpu,
+ struct sys_reg_params *p,
+ const struct sys_reg_desc *r)
+{
+ u64 idx;
+
+ if (!kvm_arm_pmu_v3_ready(vcpu))
+ return trap_raz_wi(vcpu, p, r);
+
+ if (r->CRn == 9 && r->CRm == 13) {
+ if (r->Op2 == 2) {
+ /* PMXEVCNTR_EL0 */
+ idx = vcpu_sys_reg(vcpu, PMSELR_EL0)
+ & ARMV8_PMU_COUNTER_MASK;
+ } else if (r->Op2 == 0) {
+ /* PMCCNTR_EL0 */
+ idx = ARMV8_PMU_CYCLE_IDX;
+ } else {
+ BUG();
+ }
+ } else if (r->CRn == 14 && (r->CRm & 12) == 8) {
+ /* PMEVCNTRn_EL0 */
+ idx = ((r->CRm & 3) << 3) | (r->Op2 & 7);
+ } else {
+ BUG();
+ }
+
+ if (!pmu_counter_idx_valid(vcpu, idx))
+ return false;
+
+ if (p->is_write)
+ kvm_pmu_set_counter_value(vcpu, idx, p->regval);
+ else
+ p->regval = kvm_pmu_get_counter_value(vcpu, idx);
+
+ return true;
+}
+
/* Silly macro to expand the DBG{BCR,BVR,WVR,WCR}n_EL1 registers in one go */
#define DBG_BCR_BVR_WCR_WVR_EL1(n) \
/* DBGBVRn_EL1 */ \
@@ -576,6 +614,13 @@ static bool access_pmu_evtyper(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b111), \
trap_wcr, reset_wcr, n, 0, get_wcr, set_wcr }
+/* Macro to expand the PMEVCNTRn_EL0 register */
+#define PMU_PMEVCNTR_EL0(n) \
+ /* PMEVCNTRn_EL0 */ \
+ { Op0(0b11), Op1(0b011), CRn(0b1110), \
+ CRm((0b1000 | (((n) >> 3) & 0x3))), Op2(((n) & 0x7)), \
+ access_pmu_evcntr, reset_unknown, (PMEVCNTR0_EL0 + n), }
+
/* Macro to expand the PMEVTYPERn_EL0 register */
#define PMU_PMEVTYPER_EL0(n) \
/* PMEVTYPERn_EL0 */ \
@@ -776,13 +821,13 @@ static const struct sys_reg_desc sys_reg_descs[] = {
access_pmceid },
/* PMCCNTR_EL0 */
{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b000),
- trap_raz_wi },
+ access_pmu_evcntr, reset_unknown, PMCCNTR_EL0 },
/* PMXEVTYPER_EL0 */
{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b001),
access_pmu_evtyper },
/* PMXEVCNTR_EL0 */
{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b010),
- trap_raz_wi },
+ access_pmu_evcntr },
/* PMUSERENR_EL0 */
{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1110), Op2(0b000),
trap_raz_wi },
@@ -797,6 +842,38 @@ static const struct sys_reg_desc sys_reg_descs[] = {
{ Op0(0b11), Op1(0b011), CRn(0b1101), CRm(0b0000), Op2(0b011),
NULL, reset_unknown, TPIDRRO_EL0 },
+ /* PMEVCNTRn_EL0 */
+ PMU_PMEVCNTR_EL0(0),
+ PMU_PMEVCNTR_EL0(1),
+ PMU_PMEVCNTR_EL0(2),
+ PMU_PMEVCNTR_EL0(3),
+ PMU_PMEVCNTR_EL0(4),
+ PMU_PMEVCNTR_EL0(5),
+ PMU_PMEVCNTR_EL0(6),
+ PMU_PMEVCNTR_EL0(7),
+ PMU_PMEVCNTR_EL0(8),
+ PMU_PMEVCNTR_EL0(9),
+ PMU_PMEVCNTR_EL0(10),
+ PMU_PMEVCNTR_EL0(11),
+ PMU_PMEVCNTR_EL0(12),
+ PMU_PMEVCNTR_EL0(13),
+ PMU_PMEVCNTR_EL0(14),
+ PMU_PMEVCNTR_EL0(15),
+ PMU_PMEVCNTR_EL0(16),
+ PMU_PMEVCNTR_EL0(17),
+ PMU_PMEVCNTR_EL0(18),
+ PMU_PMEVCNTR_EL0(19),
+ PMU_PMEVCNTR_EL0(20),
+ PMU_PMEVCNTR_EL0(21),
+ PMU_PMEVCNTR_EL0(22),
+ PMU_PMEVCNTR_EL0(23),
+ PMU_PMEVCNTR_EL0(24),
+ PMU_PMEVCNTR_EL0(25),
+ PMU_PMEVCNTR_EL0(26),
+ PMU_PMEVCNTR_EL0(27),
+ PMU_PMEVCNTR_EL0(28),
+ PMU_PMEVCNTR_EL0(29),
+ PMU_PMEVCNTR_EL0(30),
/* PMEVTYPERn_EL0 */
PMU_PMEVTYPER_EL0(0),
PMU_PMEVTYPER_EL0(1),
@@ -1025,6 +1102,13 @@ static const struct sys_reg_desc cp14_64_regs[] = {
{ Op1( 0), CRm( 2), .access = trap_raz_wi },
};
+/* Macro to expand the PMEVCNTRn register */
+#define PMU_PMEVCNTR(n) \
+ /* PMEVCNTRn */ \
+ { Op1(0), CRn(0b1110), \
+ CRm((0b1000 | (((n) >> 3) & 0x3))), Op2(((n) & 0x7)), \
+ access_pmu_evcntr }
+
/* Macro to expand the PMEVTYPERn register */
#define PMU_PMEVTYPER(n) \
/* PMEVTYPERn */ \
@@ -1067,9 +1151,9 @@ static const struct sys_reg_desc cp15_regs[] = {
{ Op1( 0), CRn( 9), CRm(12), Op2( 5), access_pmselr },
{ Op1( 0), CRn( 9), CRm(12), Op2( 6), access_pmceid },
{ Op1( 0), CRn( 9), CRm(12), Op2( 7), access_pmceid },
- { Op1( 0), CRn( 9), CRm(13), Op2( 0), trap_raz_wi },
+ { Op1( 0), CRn( 9), CRm(13), Op2( 0), access_pmu_evcntr },
{ Op1( 0), CRn( 9), CRm(13), Op2( 1), access_pmu_evtyper },
- { Op1( 0), CRn( 9), CRm(13), Op2( 2), trap_raz_wi },
+ { Op1( 0), CRn( 9), CRm(13), Op2( 2), access_pmu_evcntr },
{ Op1( 0), CRn( 9), CRm(14), Op2( 0), trap_raz_wi },
{ Op1( 0), CRn( 9), CRm(14), Op2( 1), trap_raz_wi },
{ Op1( 0), CRn( 9), CRm(14), Op2( 2), trap_raz_wi },
@@ -1084,6 +1168,38 @@ static const struct sys_reg_desc cp15_regs[] = {
{ Op1( 0), CRn(13), CRm( 0), Op2( 1), access_vm_reg, NULL, c13_CID },
+ /* PMEVCNTRn */
+ PMU_PMEVCNTR(0),
+ PMU_PMEVCNTR(1),
+ PMU_PMEVCNTR(2),
+ PMU_PMEVCNTR(3),
+ PMU_PMEVCNTR(4),
+ PMU_PMEVCNTR(5),
+ PMU_PMEVCNTR(6),
+ PMU_PMEVCNTR(7),
+ PMU_PMEVCNTR(8),
+ PMU_PMEVCNTR(9),
+ PMU_PMEVCNTR(10),
+ PMU_PMEVCNTR(11),
+ PMU_PMEVCNTR(12),
+ PMU_PMEVCNTR(13),
+ PMU_PMEVCNTR(14),
+ PMU_PMEVCNTR(15),
+ PMU_PMEVCNTR(16),
+ PMU_PMEVCNTR(17),
+ PMU_PMEVCNTR(18),
+ PMU_PMEVCNTR(19),
+ PMU_PMEVCNTR(20),
+ PMU_PMEVCNTR(21),
+ PMU_PMEVCNTR(22),
+ PMU_PMEVCNTR(23),
+ PMU_PMEVCNTR(24),
+ PMU_PMEVCNTR(25),
+ PMU_PMEVCNTR(26),
+ PMU_PMEVCNTR(27),
+ PMU_PMEVCNTR(28),
+ PMU_PMEVCNTR(29),
+ PMU_PMEVCNTR(30),
/* PMEVTYPERn */
PMU_PMEVTYPER(0),
PMU_PMEVTYPER(1),
@@ -1122,6 +1238,7 @@ static const struct sys_reg_desc cp15_regs[] = {
static const struct sys_reg_desc cp15_64_regs[] = {
{ Op1( 0), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
+ { Op1( 0), CRn( 0), CRm( 9), Op2( 0), access_pmu_evcntr },
{ Op1( 0), CRn( 0), CRm(12), Op2( 0), access_gic_sgi },
{ Op1( 1), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR1 },
};
diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
index 9536a24..7404424 100644
--- a/include/kvm/arm_pmu.h
+++ b/include/kvm/arm_pmu.h
@@ -39,6 +39,7 @@ struct kvm_pmu {
#define kvm_arm_pmu_v3_ready(v) ((v)->arch.pmu.ready)
u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx);
+void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu, u64 select_idx, u64 val);
void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data,
u64 select_idx);
#else
@@ -51,6 +52,8 @@ static inline u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu,
{
return 0;
}
+static inline void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu,
+ u64 select_idx, u64 val) {}
static inline void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu,
u64 data, u64 select_idx) {}
#endif
diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c
index 648c30e..96c8ffc 100644
--- a/virt/kvm/arm/pmu.c
+++ b/virt/kvm/arm/pmu.c
@@ -48,6 +48,21 @@ u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx)
}
/**
+ * kvm_pmu_set_counter_value - set PMU counter value
+ * @vcpu: The vcpu pointer
+ * @select_idx: The counter index
+ * @val: The counter value
+ */
+void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu, u64 select_idx, u64 val)
+{
+ u64 reg;
+
+ reg = (select_idx == ARMV8_PMU_CYCLE_IDX)
+ ? PMCCNTR_EL0 : PMEVCNTR0_EL0 + select_idx;
+ vcpu_sys_reg(vcpu, reg) += (s64)val - kvm_pmu_get_counter_value(vcpu, select_idx);
+}
+
+/**
* kvm_pmu_stop_counter - stop PMU counter
* @pmc: The PMU counter pointer
*
--
2.0.4
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