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-rw-r--r--Documentation/virt/kvm/devices/vcpu.rst36
1 files changed, 34 insertions, 2 deletions
diff --git a/Documentation/virt/kvm/devices/vcpu.rst b/Documentation/virt/kvm/devices/vcpu.rst
index 60a29972d3f1..716aa3edae14 100644
--- a/Documentation/virt/kvm/devices/vcpu.rst
+++ b/Documentation/virt/kvm/devices/vcpu.rst
@@ -70,7 +70,7 @@ irqchip.
-ENODEV PMUv3 not supported or GIC not initialized
-ENXIO PMUv3 not properly configured or in-kernel irqchip not
configured as required prior to calling this attribute
- -EBUSY PMUv3 already initialized
+ -EBUSY PMUv3 already initialized or a VCPU has already run
-EINVAL Invalid filter range
======= ======================================================
@@ -104,11 +104,43 @@ hardware event. Filtering event 0x1E (CHAIN) has no effect either, as it
isn't strictly speaking an event. Filtering the cycle counter is possible
using event 0x11 (CPU_CYCLES).
+1.4 ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_SET_PMU
+------------------------------------------
+
+:Parameters: in kvm_device_attr.addr the address to an int representing the PMU
+ identifier.
+
+:Returns:
+
+ ======= ====================================================
+ -EBUSY PMUv3 already initialized, a VCPU has already run or
+ an event filter has already been set
+ -EFAULT Error accessing the PMU identifier
+ -ENXIO PMU not found
+ -ENODEV PMUv3 not supported or GIC not initialized
+ -ENOMEM Could not allocate memory
+ ======= ====================================================
+
+Request that the VCPU uses the specified hardware PMU when creating guest events
+for the purpose of PMU emulation. The PMU identifier can be read from the "type"
+file for the desired PMU instance under /sys/devices (or, equivalent,
+/sys/bus/even_source). This attribute is particularly useful on heterogeneous
+systems where there are at least two CPU PMUs on the system. The PMU that is set
+for one VCPU will be used by all the other VCPUs. It isn't possible to set a PMU
+if a PMU event filter is already present.
+
+Note that KVM will not make any attempts to run the VCPU on the physical CPUs
+associated with the PMU specified by this attribute. This is entirely left to
+userspace. However, attempting to run the VCPU on a physical CPU not supported
+by the PMU will fail and KVM_RUN will return with
+exit_reason = KVM_EXIT_FAIL_ENTRY and populate the fail_entry struct by setting
+hardare_entry_failure_reason field to KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED and
+the cpu field to the processor id.
2. GROUP: KVM_ARM_VCPU_TIMER_CTRL
=================================
-:Architectures: ARM, ARM64
+:Architectures: ARM64
2.1. ATTRIBUTES: KVM_ARM_VCPU_TIMER_IRQ_VTIMER, KVM_ARM_VCPU_TIMER_IRQ_PTIMER
-----------------------------------------------------------------------------