Re: [PATCH v1 07/10] perf/x86/uncore: allow more than one fixed counter per box

["Yan, Zheng" <zheng.z.yan@intel.com>]

On 02/03/2014 08:55 PM, Stephane Eranian wrote:
> This patch modifies some of the helper functions to support
> more than one fixed counter per uncore PCI PMU box.
> 
> Signed-off-by: Stephane Eranian <eranian@google.com>
> ---
>  arch/x86/kernel/cpu/perf_event_intel_uncore.c |    4 ++--
>  arch/x86/kernel/cpu/perf_event_intel_uncore.h |   22 +++++++++++++---------
>  2 files changed, 15 insertions(+), 11 deletions(-)
> 
> diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.c b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
> index 2980994c..69a4ad0 100644
> --- a/arch/x86/kernel/cpu/perf_event_intel_uncore.c
> +++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
> @@ -2777,8 +2777,8 @@ static void uncore_assign_hw_event(struct intel_uncore_box *box, struct perf_eve
>  	hwc->idx = idx;
>  	hwc->last_tag = ++box->tags[idx];
>  
> -	if (hwc->idx == UNCORE_PMC_IDX_FIXED) {
> -		hwc->event_base = uncore_fixed_ctr(box);
> +	if (hwc->idx >= UNCORE_PMC_IDX_FIXED) {
> +		hwc->event_base = uncore_fixed_ctr(box, idx);
>  		hwc->config_base = uncore_fixed_ctl(box);
>  		return;
>  	}
> diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.h b/arch/x86/kernel/cpu/perf_event_intel_uncore.h
> index 433c180..c63a3ff 100644
> --- a/arch/x86/kernel/cpu/perf_event_intel_uncore.h
> +++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.h
> @@ -538,9 +538,18 @@ static inline unsigned uncore_pci_fixed_ctl(struct intel_uncore_box *box)
>  	return box->pmu->type->fixed_ctl;
>  }
>  
> -static inline unsigned uncore_pci_fixed_ctr(struct intel_uncore_box *box)
> +static inline int uncore_fixed_ctr_bits(struct intel_uncore_box *box)
> +{
> +	return box->pmu->type->fixed_ctr_bits;
> +}
> +
> +static inline unsigned uncore_pci_fixed_ctr(struct intel_uncore_box *box,
> +					    int idx)
>  {
> -	return box->pmu->type->fixed_ctr;
> +	int bits = uncore_fixed_ctr_bits(box);
> +	int bytes = round_up(bits, 8);
> +
> +	return idx * bytes + box->pmu->type->fixed_ctr;
>  }

should this be:
int bytes = round_up(bits, 32) / 8;
return (idx - UNCORE_PMC_IDX_FIXED) * bytes + box->pmu->type->fixed_ctr;
?

Regards
Yan, Zheng

>  
>  static inline
> @@ -554,11 +563,6 @@ static inline int uncore_perf_ctr_bits(struct intel_uncore_box *box)
>  	return box->pmu->type->perf_ctr_bits;
>  }
>  
> -static inline int uncore_fixed_ctr_bits(struct intel_uncore_box *box)
> -{
> -	return box->pmu->type->fixed_ctr_bits;
> -}
> -
>  static inline
>  unsigned uncore_pci_perf_ctr(struct intel_uncore_box *box, int idx)
>  {
> @@ -627,10 +631,10 @@ unsigned uncore_fixed_ctl(struct intel_uncore_box *box)
>  }
>  
>  static inline
> -unsigned uncore_fixed_ctr(struct intel_uncore_box *box)
> +unsigned uncore_fixed_ctr(struct intel_uncore_box *box, int idx)
>  {
>  	if (box->pci_dev)
> -		return uncore_pci_fixed_ctr(box);
> +		return uncore_pci_fixed_ctr(box, idx);
>  	else
>  		return uncore_msr_fixed_ctr(box);
>  }
>