KVM: x86/pmu: Adjust precise_ip to emulate Ice Lake guest PDIR counter

Browse source

The PEBS-PDIR facility on Ice Lake server is supported on IA31_FIXED0 only.
If the guest configures counter 32 and PEBS is enabled, the PEBS-PDIR
facility is supposed to be used, in which case KVM adjusts attr.precise_ip
to 3 and request host perf to assign the exactly requested counter or fail.

The CPU model check is also required since some platforms may place the
PEBS-PDIR facility in another counter index.

Signed-off-by: Like Xu <like.xu@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Message-Id: <20220411101946.20262-10-likexu@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

...

This commit is contained in:

Like Xu 2022-04-11 18:19:38 +08:00 • committed by Paolo Bonzini

parent 79f3e3b583

commit 6ebe44366b

3 changed files with 11 additions and 1 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

2

arch/x86/events/intel/core.c

View file

2

arch/x86/kvm/pmu.c

View file

8

arch/x86/kvm/pmu.h

View file