Re: [PATCH v2 2/6] KVM: x86/pmu: Refactoring find_arch_event() to pmc_perf_hw_id()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 14/2/2022 6:14 pm, Ravi Bangoria wrote:


On 11-Feb-22 11:46 PM, Jim Mattson wrote:
On Fri, Feb 11, 2022 at 1:56 AM Ravi Bangoria <ravi.bangoria@xxxxxxx> wrote:



On 10-Feb-22 4:58 PM, Like Xu wrote:
cc Kim and Ravi to help confirm more details about this change.

On 10/2/2022 3:30 am, Jim Mattson wrote:
By the way, the following events from amd_event_mapping[] are not
listed in the Milan PPR:
{ 0x7d, 0x07, PERF_COUNT_HW_CACHE_REFERENCES }
{ 0x7e, 0x07, PERF_COUNT_HW_CACHE_MISSES }
{ 0xd0, 0x00, PERF_COUNT_HW_STALLED_CYCLES_FRONTEND }
{ 0xd1, 0x00, PERF_COUNT_HW_STALLED_CYCLES_BACKEND }

Perhaps we should build a table based on amd_f17h_perfmon_event_map[]
for newer AMD processors?

So do we need another amd_f19h_perfmon_event_map[] in the host perf code ?


I think Like's other patch series to unify event mapping across kvm
and host will fix it. No?
https://lore.kernel.org/lkml/20220117085307.93030-4-likexu@xxxxxxxxxxx

Yes, that should fix it. But why do we even bother? What is the
downside of using PERF_TYPE_RAW all of the time?

There are few places where PERF_TYPE_HARDWARE and PERF_TYPE_RAW are treated
differently. Ex, x86_pmu_event_init(), perf_init_event(). So I think it makes
sense to keep using PERF_TYPE_HARDWARE for generalized events?

Ravi



[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux