[PATCH v7 02/19] KVM: ARM64: Define PMU data structure for each vcpu

Shannon Zhao
2015-12-15T08:49:22Z

From: Shannon Zhao <shannon.zhao@linaro.org>

Here we plan to support virtual PMU for guest by full software
emulation, so define some basic structs and functions preparing for
futher steps. Define struct kvm_pmc for performance monitor counter and
struct kvm_pmu for performance monitor unit for each vcpu. According to
ARMv8 spec, the PMU contains at most 32(ARMV8_MAX_COUNTERS) counters.

Since this only supports ARM64 (or PMUv3), add a separate config symbol
for it.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
---
arch/arm64/include/asm/kvm_host.h | 2 ++
arch/arm64/kvm/Kconfig | 7 +++++++
include/kvm/arm_pmu.h | 42 +++++++++++++++++++++++++++++++++++++++
3 files changed, 51 insertions(+)
create mode 100644 include/kvm/arm_pmu.h

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index a35ce72..42e15bb 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -37,6 +37,7 @@

#include <kvm/arm_vgic.h>
#include <kvm/arm_arch_timer.h>
+#include <kvm/arm_pmu.h>

#define KVM_MAX_VCPUS VGIC_V3_MAX_CPUS

@@ -132,6 +133,7 @@ struct kvm_vcpu_arch {
/* VGIC state */
struct vgic_cpu vgic_cpu;
struct arch_timer_cpu timer_cpu;
+ struct kvm_pmu pmu;

/*
* Anything that is not used directly from assembly code goes
diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index a5272c0..de7450d 100644
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -36,6 +36,7 @@ config KVM
select HAVE_KVM_EVENTFD
select HAVE_KVM_IRQFD
select KVM_ARM_VGIC_V3
+ select KVM_ARM_PMU if HW_PERF_EVENTS
---help---
Support hosting virtualized guest machines.
We don't support KVM with 16K page tables yet, due to the multiple
@@ -48,6 +49,12 @@ config KVM_ARM_HOST
---help---
Provides host support for ARM processors.

+config KVM_ARM_PMU
+ bool
+ ---help---
+ Adds support for a virtual Performance Monitoring Unit (PMU) in
+ virtual machines.
+
source drivers/vhost/Kconfig

endif # VIRTUALIZATION
diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
new file mode 100644
index 0000000..ddcb5b2
--- /dev/null
+++ b/include/kvm/arm_pmu.h
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2015 Linaro Ltd.
+ * Author: Shannon Zhao <shannon.zhao@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __ASM_ARM_KVM_PMU_H
+#define __ASM_ARM_KVM_PMU_H
+
+#ifdef CONFIG_KVM_ARM_PMU
+
+#include <linux/perf_event.h>
+#include <asm/pmu.h>
+
+struct kvm_pmc {
+ u8 idx;/* index into the pmu->pmc array */
+ struct perf_event *perf_event;
+ u64 bitmask;
+};
+
+struct kvm_pmu {
+ /* PMU IRQ Number per VCPU */
+ int irq_num;
+ struct kvm_pmc pmc[ARMV8_MAX_COUNTERS];
+};
+#else
+struct kvm_pmu {
+};
+#endif
+
+#endif
--
2.0.4