| Message ID | 20230307141400.1486314-3-aaronlewis@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix "Instructions Retired" from incorrectly counting | expand |
LOL, the shortlog is hilariously generic. I realize it's annoying to have to clarify what test is affected, but it's not exactly hard, e.g. KVM: selftests: Add a common helper for the PMU event filter guest code On Tue, Mar 07, 2023, Aaron Lewis wrote: > Split out the common parts of the Intel and AMD guest code into a > helper function. This is in preparation for adding > additional counters to the test. Similar whining here Split out the common parts of the Intel and AMD guest code in the PMU event filter test into a helper function. This is in preparation for adding additional counters to the test. > > No functional changes intended. > > Signed-off-by: Aaron Lewis <aaronlewis@google.com> > --- > .../kvm/x86_64/pmu_event_filter_test.c | 31 ++++++++++++------- > 1 file changed, 20 insertions(+), 11 deletions(-) > > diff --git a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c > index bad7ef8c5b92..f33079fc552b 100644 > --- a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c > +++ b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c > @@ -100,6 +100,17 @@ static void check_msr(uint32_t msr, uint64_t bits_to_flip) > GUEST_SYNC(0); > } > > +static uint64_t test_guest(uint32_t msr_base) test_guest() is again too generic, and arguably inaccurate, e.g. it's not really testing anything, just running code and capturing event counts. How about run_and_measure_loop()?
diff --git a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c index bad7ef8c5b92..f33079fc552b 100644 --- a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c +++ b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c @@ -100,6 +100,17 @@ static void check_msr(uint32_t msr, uint64_t bits_to_flip) GUEST_SYNC(0); } +static uint64_t test_guest(uint32_t msr_base) +{ + uint64_t br0, br1; + + br0 = rdmsr(msr_base + 0); + __asm__ __volatile__("loop ." : "+c"((int){NUM_BRANCHES})); + br1 = rdmsr(msr_base + 0); + + return br1 - br0; +} + static void intel_guest_code(void) { check_msr(MSR_CORE_PERF_GLOBAL_CTRL, 1); @@ -108,16 +119,15 @@ static void intel_guest_code(void) GUEST_SYNC(1); for (;;) { - uint64_t br0, br1; + uint64_t count; wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, 0); wrmsr(MSR_P6_EVNTSEL0, ARCH_PERFMON_EVENTSEL_ENABLE | ARCH_PERFMON_EVENTSEL_OS | INTEL_BR_RETIRED); - wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, 1); - br0 = rdmsr(MSR_IA32_PMC0); - __asm__ __volatile__("loop ." : "+c"((int){NUM_BRANCHES})); - br1 = rdmsr(MSR_IA32_PMC0); - GUEST_SYNC(br1 - br0); + wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, 0x1); + + count = test_guest(MSR_IA32_PMC0); + GUEST_SYNC(count); } } @@ -133,15 +143,14 @@ static void amd_guest_code(void) GUEST_SYNC(1); for (;;) { - uint64_t br0, br1; + uint64_t count; wrmsr(MSR_K7_EVNTSEL0, 0); wrmsr(MSR_K7_EVNTSEL0, ARCH_PERFMON_EVENTSEL_ENABLE | ARCH_PERFMON_EVENTSEL_OS | AMD_ZEN_BR_RETIRED); - br0 = rdmsr(MSR_K7_PERFCTR0); - __asm__ __volatile__("loop ." : "+c"((int){NUM_BRANCHES})); - br1 = rdmsr(MSR_K7_PERFCTR0); - GUEST_SYNC(br1 - br0); + + count = test_guest(MSR_K7_PERFCTR0); + GUEST_SYNC(count); } }
Split out the common parts of the Intel and AMD guest code into a helper function. This is in preparation for adding additional counters to the test. No functional changes intended. Signed-off-by: Aaron Lewis <aaronlewis@google.com> --- .../kvm/x86_64/pmu_event_filter_test.c | 31 ++++++++++++------- 1 file changed, 20 insertions(+), 11 deletions(-)