[kvm-unit-tests PATCH v3 0/4] arm: pmu: Add support for PMUv3p5

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The first commit fixes the tests when running on PMUv3p5. The issue is that
PMUv3p5 uses 64-bit counters irrespective of whether the PMU is configured
for overflowing at 32 or 64-bits. Tests are currently failing [0] on
PMUv3p5 because of this. They wrongly assume that values will be wrapped
around 32-bits, but they overflow into the other half of the 64-bit
counters.

The second and third commits add new tests for 64-bit overflows, a feature
added with PMUv3p5 (PMCR_EL0.LP == 1). This is done by running all
overflow-related tests in two modes: with 32-bit and 64-bit overflows.
The fourt commit changes the value reporting to use %lx instead of %ld.

This series was tested on PMUv3p5 and PMUv3p4 using the ARM Fast Model and
kvmtool.  All tests pass on both PMUv3p5 and PMUv3p4 when using Marc's
PMUv3p5 series [0], plus the suggestion made at [1]. Didn't test AArch32.

Changes from v2:
- used Oliver's suggestion of using pmevcntr_mask() for masking counters to
  32 or 64 bits, instead of casting to uint32_t or uint64_t.
- removed ALL_SET_AT() in favor of pmevcntr_mask(). (Oliver)
- moved the change to have odd counter overflows at 64-bits from first to
  third commit.
- renamed PRE_OVERFLOW macro to PRE_OVERFLOW_32, and PRE_OVERFLOW_AT() to
  PRE_OVERFLOW().

Changes from v1 (all suggested by Alexandru):
- report counter values in hexadecimal
- s/overflow_at_64bits/unused for all chained tests
- check that odd counters do not increment when using overflow_at_64bits
  (pmcr.LP=1)
- test 64-bit odd counters overflows
- switch confusing var names in test_chained_sw_incr(): cntr0 <-> cntr1

[0] https://lore.kernel.org/kvmarm/20221113163832.3154370-1-maz@xxxxxxxxxx/
[1] https://lore.kernel.org/kvmarm/Y4jasyxvFRNvvmox@xxxxxxxxxx/

Ricardo Koller (4):
  arm: pmu: Fix overflow checks for PMUv3p5 long counters
  arm: pmu: Prepare for testing 64-bit overflows
  arm: pmu: Add tests for 64-bit overflows
  arm: pmu: Print counter values as hexadecimals

 arm/pmu.c | 260 ++++++++++++++++++++++++++++++++++--------------------
 1 file changed, 163 insertions(+), 97 deletions(-)

-- 
2.39.0.314.g84b9a713c41-goog




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