diff options
| author | Sean Christopherson <[email protected]> | 2023-11-10 02:28:53 +0000 |
|---|---|---|
| committer | Sean Christopherson <[email protected]> | 2024-02-01 17:35:48 +0000 |
| commit | d2b321ea9380564510d281d45ccd2b424da14e7f (patch) | |
| tree | 8f2e98b5310b214113728440196d7dc3ed12dc80 /drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c | |
| parent | KVM: x86/pmu: Add macros to iterate over all PMCs given a bitmap (diff) | |
| download | kernel-d2b321ea9380564510d281d45ccd2b424da14e7f.tar.gz kernel-d2b321ea9380564510d281d45ccd2b424da14e7f.zip | |
KVM: x86/pmu: Process only enabled PMCs when emulating events in software
Mask off disabled counters based on PERF_GLOBAL_CTRL *before* iterating
over PMCs to emulate (branch) instruction required events in software. In
the common case where the guest isn't utilizing the PMU, pre-checking for
enabled counters turns a relatively expensive search into a few AND uops
and a Jcc.
Sadly, PMUs without PERF_GLOBAL_CTRL, e.g. most existing AMD CPUs, are out
of luck as there is no way to check that a PMC isn't being used without
checking the PMC's event selector.
Cc: Konstantin Khorenko <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sean Christopherson <[email protected]>
Diffstat (limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c')
0 files changed, 0 insertions, 0 deletions