On Thu, May 30, 2013 at 07:47:18PM +0200, Paolo Bonzini wrote: > This patch includes two fixes for SB: > > * the 3rd fixed counter ("ref cpu cycles") can sometimes report > less than the number of iterations > > * there is an 8th counter which causes out of bounds accesses > to gp_event or check_counters_many's cnt array > > There is still a bug in KVM, because the "pmu all counters-0" > test fails. (It passes if you use any 6 of the 8 gp counters, > fails if you use 7 or 8). > > Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> Applied, thanks. > --- > x86/pmu.c | 21 +++++++++++++++------ > 1 file changed, 15 insertions(+), 6 deletions(-) > > diff --git a/x86/pmu.c b/x86/pmu.c > index 2c46f31..dca753a 100644 > --- a/x86/pmu.c > +++ b/x86/pmu.c > @@ -88,9 +88,10 @@ struct pmu_event { > }, fixed_events[] = { > {"fixed 1", MSR_CORE_PERF_FIXED_CTR0, 10*N, 10.2*N}, > {"fixed 2", MSR_CORE_PERF_FIXED_CTR0 + 1, 1*N, 30*N}, > - {"fixed 3", MSR_CORE_PERF_FIXED_CTR0 + 2, 1*N, 30*N} > + {"fixed 3", MSR_CORE_PERF_FIXED_CTR0 + 2, 0.1*N, 30*N} > }; > > +static int num_counters; > static int tests, failures; > > char *buf; > @@ -237,7 +238,7 @@ static void check_gp_counter(struct pmu_event *evt) > }; > int i; > > - for (i = 0; i < eax.split.num_counters; i++, cnt.ctr++) { > + for (i = 0; i < num_counters; i++, cnt.ctr++) { > cnt.count = 0; > measure(&cnt, 1); > report(evt->name, i, verify_event(cnt.count, evt)); > @@ -276,7 +277,7 @@ static void check_counters_many(void) > pmu_counter_t cnt[10]; > int i, n; > > - for (i = 0, n = 0; n < eax.split.num_counters; i++) { > + for (i = 0, n = 0; n < num_counters; i++) { > if (ebx.full & (1 << i)) > continue; > > @@ -316,10 +317,10 @@ static void check_counter_overflow(void) > /* clear status before test */ > wrmsr(MSR_CORE_PERF_GLOBAL_OVF_CTRL, rdmsr(MSR_CORE_PERF_GLOBAL_STATUS)); > > - for (i = 0; i < eax.split.num_counters + 1; i++, cnt.ctr++) { > + for (i = 0; i < num_counters + 1; i++, cnt.ctr++) { > uint64_t status; > int idx; > - if (i == eax.split.num_counters) > + if (i == num_counters) > cnt.ctr = fixed_events[0].unit_sel; > if (i % 2) > cnt.config |= EVNTSEL_INT; > @@ -355,7 +356,7 @@ static void check_rdpmc(void) > uint64_t val = 0x1f3456789ull; > int i; > > - for (i = 0; i < eax.split.num_counters; i++) { > + for (i = 0; i < num_counters; i++) { > uint64_t x = (val & 0xffffffff) | > ((1ull << (eax.split.bit_width - 32)) - 1) << 32; > wrmsr(MSR_IA32_PERFCTR0 + i, val); > @@ -395,6 +396,10 @@ int main(int ac, char **av) > printf("Fixed counters: %d\n", edx.split.num_counters_fixed); > printf("Fixed counter width: %d\n", edx.split.bit_width_fixed); > > + num_counters = eax.split.num_counters; > + if (num_counters > ARRAY_SIZE(gp_events)) > + num_counters = ARRAY_SIZE(gp_events); > + > apic_write(APIC_LVTPC, PC_VECTOR); > > check_gp_counters(); > -- > 1.8.2.1 > > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html