[PATCH 15/18] KVM: ARM64: Add reset and access handlers for PMSWINC_EL0 register
From: shannon.zhao at linaro.org <hidden>
Date: 2015-07-06 02:17:45
Also in:
kvm, kvmarm
Subsystem:
arm64 port (aarch64 architecture), kernel virtual machine (kvm), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Paolo Bonzini, Marc Zyngier, Oliver Upton, Linus Torvalds
From: Shannon Zhao <redacted> Add access handler which emulates writing and reading PMSWINC_EL0 register and add support for creating software increment event. Signed-off-by: Shannon Zhao <redacted> --- arch/arm64/kvm/sys_regs.c | 15 ++++++++++++++- include/kvm/arm_pmu.h | 2 ++ virt/kvm/arm/pmu.c | 20 ++++++++++++++++++++ 3 files changed, 36 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index d5984d0..70afcba 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c@@ -535,6 +535,19 @@ static bool access_pmuserenr(struct kvm_vcpu *vcpu, return true; } +/* PMSWINC_EL0 accessor. */ +static bool access_pmswinc(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + const struct sys_reg_desc *r) +{ + if (p->is_write) + kvm_pmu_software_increment(vcpu, *vcpu_reg(vcpu, p->Rt)); + else + return read_zero(vcpu, p); + + 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 */ \
@@ -738,7 +751,7 @@ static const struct sys_reg_desc sys_reg_descs[] = { access_pmovsclr, reset_unknown, PMOVSCLR_EL0 }, /* PMSWINC_EL0 */ { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b100), - trap_raz_wi }, + access_pmswinc, reset_unknown, PMSWINC_EL0 }, /* PMSELR_EL0 */ { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b101), access_pmselr, reset_unknown, PMSELR_EL0 },
diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
index 4f3d8a6..6985809 100644
--- a/include/kvm/arm_pmu.h
+++ b/include/kvm/arm_pmu.h@@ -54,6 +54,7 @@ void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, unsigned long val); void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, unsigned long val); void kvm_pmu_disable_interrupt(struct kvm_vcpu *vcpu, unsigned long val); void kvm_pmu_enable_interrupt(struct kvm_vcpu *vcpu, unsigned long val); +void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, unsigned long val); void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, unsigned long data, unsigned long select_idx); void kvm_pmu_init(struct kvm_vcpu *vcpu);
@@ -70,6 +71,7 @@ void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, unsigned long val) {} void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, unsigned long val) {} void kvm_pmu_disable_interrupt(struct kvm_vcpu *vcpu, unsigned long val) {} void kvm_pmu_enable_interrupt(struct kvm_vcpu *vcpu, unsigned long val) {} +void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, unsigned long val) {} void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, unsigned long data, unsigned long select_idx) {} static inline void kvm_pmu_init(struct kvm_vcpu *vcpu) {}
diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c
index 7023ad5..e655426 100644
--- a/virt/kvm/arm/pmu.c
+++ b/virt/kvm/arm/pmu.c@@ -203,6 +203,22 @@ void kvm_pmu_disable_interrupt(struct kvm_vcpu *vcpu, unsigned long val) } /** + * kvm_pmu_software_increment - do software increment + * @vcpu: The vcpu pointer + * @val: the value guest writes to PMSWINC_EL0 register + */ +void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, unsigned long val) +{ + int select_idx = find_first_bit(&val, 31); + struct kvm_pmu *pmu = &vcpu->arch.pmu; + struct kvm_pmc *pmc = &pmu->pmc[select_idx]; + + if (pmu->user_enable & 0x3) + if ((pmc->eventsel == 0) && (pmc->enable == true)) + pmc->counter++; +} + +/** * kvm_pmu_find_hw_event - find hardware event * @pmu: The pmu pointer * @event_select: The number of selected event type
@@ -280,6 +296,10 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, unsigned long data, kvm_pmu_stop_counter(vcpu, select_idx); pmc->eventsel = data & ARMV8_EVTYPE_EVENT; + /* For software increment event we don't need to create perf event */ + if (pmc->eventsel == 0) + return; + config = kvm_pmu_find_hw_event(pmu, pmc->eventsel); if (config != PERF_COUNT_HW_MAX) { type = PERF_TYPE_HARDWARE;
--
2.1.0