Hi Daniel,
On 4/16/24 01:29, Daniel P. Berrangé wrote:
On Mon, Apr 08, 2024 at 10:49:40PM -0400, Shaoqin Huang wrote:
The KVM_ARM_VCPU_PMU_V3_FILTER provides the ability to let the VMM decide
which PMU events are provided to the guest. Add a new option
`kvm-pmu-filter` as -cpu sub-option to set the PMU Event Filtering.
Without the filter, all PMU events are exposed from host to guest by
default. The usage of the new sub-option can be found from the updated
document (docs/system/arm/cpu-features.rst).
Here is an example which shows how to use the PMU Event Filtering, when
we launch a guest by use kvm, add such command line:
# qemu-system-aarch64 \
-accel kvm \
-cpu host,kvm-pmu-filter="D:0x11-0x11"
I'm still against implementing this one-off custom parsed syntax
for kvm-pmu-filter values. Once this syntax exists, we're locked
into back-compatibility for multiple releases, and it will make
a conversion to QAPI/JSON harder.
Thanks for your effort of reviewing my patch. I think if I need cost
more time about the QAPI, that's outside my initial idea and deviate
from supporting the PMU Filter.
So I decide to not update this patch now. And wait until I have time to
look into the QAPI or the -cpu option has been transformed to QAPI format.
Thanks,
Shaoqin
With regards,
Daniel
--
Shaoqin