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| author | Sean Christopherson <[email protected]> | 2021-04-12 16:21:35 +1200 |
|---|---|---|
| committer | Paolo Bonzini <[email protected]> | 2021-04-20 04:18:54 -0400 |
| commit | 4e66c0cb79b732b01b82e094b21b8e22a20dff83 (patch) | |
| tree | ae0717a6e670831530c30ff88a54a17b45d80bcb /tools/perf/scripts/python/stackcollapse.py | |
| parent | 00e7646c3563d2f1a46a8fa1824c32373d77a8be (diff) | |
KVM: x86: Add support for reverse CPUID lookup of scattered features
Introduce a scheme that allows KVM's CPUID magic to support features
that are scattered in the kernel's feature words. To advertise and/or
query guest support for CPUID-based features, KVM requires the bit
number of an X86_FEATURE_* to match the bit number in its associated
CPUID entry. For scattered features, this does not hold true.
Add a framework to allow defining KVM-only words, stored in
kvm_cpu_caps after the shared kernel caps, that can be used to gather
the scattered feature bits by translating X86_FEATURE_* flags into their
KVM-defined feature.
Note, because reverse_cpuid_check() effectively forces kvm_cpu_caps
lookups to be resolved at compile time, there is no runtime cost for
translating from kernel-defined to kvm-defined features.
More details here: https://lkml.kernel.org/r/X/[email protected]
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Kai Huang <[email protected]>
Message-Id: <16cad8d00475f67867fb36701fc7fb7c1ec86ce1.1618196135.git.kai.huang@intel.com>
Signed-off-by: Paolo Bonzini <[email protected]>
Diffstat (limited to 'tools/perf/scripts/python/stackcollapse.py')
0 files changed, 0 insertions, 0 deletions