This patchset adds a pmu=[on/off] option to enable/disable vPMU support
for guest VM. There are several reasons to justify this option. First,
vPMU can be problematic for cross-migration between different SoC as perf
counters are architecture-dependent. It is more flexible to have an option
to turn it on/off. Secondly Secondly this option matches the "pmu" option
as supported in libvirt. To make sure backward compatible, a PMU property
is added to mach-virt machine types.
V1->V2:
* keep the original field name as "has_pmu"
* add a warning message when PMU is turned on without KVM
* use the feature bit to check PMU availability, instead of using has_pmu
* add PMU compat support to mach-virt machine type
RFC->V1:
* set default pmu=off
* change struct ARMCPU field name "has_pmu" ==> "has_host_pmu"
* like el3, add a new feature ARM_FEATURE_HOST_PMU
* "pmu" property becomes CPU dependent. Only cortex-a53/cortex-a57/host
running on kvm supports this option.
-Wei
Wei Huang (2):
arm64: Add an option to turn on/off vPMU support
arm: virt: add PMU property to machvirt machine type
hw/arm/virt-acpi-build.c | 2 +-
hw/arm/virt.c | 14 +++++++++++++-
target-arm/cpu.c | 22 ++++++++++++++++++++++
target-arm/cpu.h | 1 +
target-arm/cpu64.c | 2 ++
target-arm/kvm64.c | 17 +++++++++++++----
6 files changed, 52 insertions(+), 6 deletions(-)
--
1.8.3.1
