Re: [PATCH] kvm-unit-tests: x86: pmu: call measure for every counter in check_counters_many

[Paolo Bonzini <pbonzini@redhat.com>]

Il 14/08/2014 22:58, Chris J Arges ha scritto:
> In the check_counters_many function measure was only being called on the last
> counter, causing the pmu test to fail.

I don't understand.  measure loops on all N counters and calls
start_event (which in turn calls global_enable) and stop_event (which
calls global_disable) on all counters.

> This ensures that measure is called for
> each counter in the array before calling verify_counter.

Actually the point of this test is to run the loop while all the
counters are active, so this patch is just masking another bug.

Paolo

> Signed-off-by: Chris J Arges <chris.j.arges@canonical.com>
> ---
>  x86/pmu.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/x86/pmu.c b/x86/pmu.c
> index 5c85146..3402d1e 100644
> --- a/x86/pmu.c
> +++ b/x86/pmu.c
> @@ -287,11 +287,11 @@ static void check_counters_many(void)
>  		n++;
>  	}
>  
> -	measure(cnt, n);
> -
> -	for (i = 0; i < n; i++)
> +	for (i = 0; i < n; i++) {
> +		measure(&cnt[i], 1);
>  		if (!verify_counter(&cnt[i]))
>  			break;
> +	}
>  
>  	report("all counters", i == n);
>  }
>