[PATCH v4 00/16] KVM: arm64: PMU: Fixing chained events, and PMUv3p5 support

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Ricardo reported[0] that our PMU emulation was busted when it comes to
chained events, as we cannot expose the overflow on a 32bit boundary
(which the architecture requires).

This series aims at fixing this (by deleting a lot of code), and as a
bonus adds support for PMUv3p5, as this requires us to fix a few more
things.

Tested on A53 (PMUv3) and QEMU (PMUv3p5).

* From v3 [3]:
  - Independent tracking of unimplemented and implemented revisions
  - Simplified counter enable/disable
  - Simplified the vcpu address computation on overflow notification
  - Added one patch to move from vcpu+index to pmc
  - Rebased on 6.1-rc3

* From v2 [2]:
  - Some tightening of userspace access to ID_{AA64,}DFR0_EL1

* From v1 [1]:
  - Rebased on 6.1-rc2
  - New patch advertising that we always support the CHAIN event
  - Plenty of bug fixes (idreg handling, AArch32, overflow narrowing)
  - Tons of cleanups
  - All kudos to Oliver and Reiji for spending the time to review this
    mess, and Ricardo for finding more bugs!

[0] https://lore.kernel.org/r/20220805004139.990531-1-ricarkol@xxxxxxxxxx
[1] https://lore.kernel.org/r/20220805135813.2102034-1-maz@xxxxxxxxxx
[2] https://lore.kernel.org/r/20221028105402.2030192-1-maz@xxxxxxxxxx
[3] https://lore.kernel.org/r/20221107085435.2581641-1-maz@xxxxxxxxxx

Marc Zyngier (16):
  arm64: Add ID_DFR0_EL1.PerfMon values for PMUv3p7 and IMP_DEF
  KVM: arm64: PMU: Align chained counter implementation with
    architecture pseudocode
  KVM: arm64: PMU: Always advertise the CHAIN event
  KVM: arm64: PMU: Distinguish between 64bit counter and 64bit overflow
  KVM: arm64: PMU: Narrow the overflow checking when required
  KVM: arm64: PMU: Only narrow counters that are not 64bit wide
  KVM: arm64: PMU: Add counter_index_to_*reg() helpers
  KVM: arm64: PMU: Simplify setting a counter to a specific value
  KVM: arm64: PMU: Do not let AArch32 change the counters' top 32 bits
  KVM: arm64: PMU: Move the ID_AA64DFR0_EL1.PMUver limit to VM creation
  KVM: arm64: PMU: Allow ID_AA64DFR0_EL1.PMUver to be set from userspace
  KVM: arm64: PMU: Allow ID_DFR0_EL1.PerfMon to be set from userspace
  KVM: arm64: PMU: Implement PMUv3p5 long counter support
  KVM: arm64: PMU: Allow PMUv3p5 to be exposed to the guest
  KVM: arm64: PMU: Simplify vcpu computation on perf overflow
    notification
  KVM: arm64: PMU: Make kvm_pmc the main data structure

 arch/arm64/include/asm/kvm_host.h |   4 +
 arch/arm64/include/asm/sysreg.h   |   2 +
 arch/arm64/kvm/arm.c              |   6 +
 arch/arm64/kvm/pmu-emul.c         | 475 ++++++++++++------------------
 arch/arm64/kvm/sys_regs.c         | 139 ++++++++-
 include/kvm/arm_pmu.h             |  15 +-
 6 files changed, 345 insertions(+), 296 deletions(-)

-- 
2.34.1




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