Subject: Re: [PATCH v2 3/5] perf: Rename perf_event_read_value

From: Peter Zijlstra <[email-masked]>
Date: Wed, 8 Apr 2015 14:24:59 +0200

On Tue, Apr 07, 2015 at 05:34:57PM -0700, Sukadev Bhattiprolu wrote:
> perf_event_read_value() is mostly computing the event count and enabled/
> running times. Move the perf_event_read() into caller and rename
> perf_event_read_value() to perf_event_compute_values().
> 
> Changelog[v2]
> 	Export symbol perf_event_read() since x86/kvm needs it now.

FWIW these changed since last things go below the --- since they're
pointless for the permanent record.

> Signed-off-by: Sukadev Bhattiprolu <[email-masked]>
> ---
>  arch/x86/kvm/pmu.c         |    6 ++++--
>  include/linux/perf_event.h |    3 ++-
>  kernel/events/core.c       |   18 +++++++++++-------
>  3 files changed, 17 insertions(+), 10 deletions(-)
> 
> diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
> index 8e6b7d8..5896cb1 100644
> --- a/arch/x86/kvm/pmu.c
> +++ b/arch/x86/kvm/pmu.c
> @@ -144,9 +144,11 @@ static u64 read_pmc(struct kvm_pmc *pmc)
>  
>  	counter = pmc->counter;
>  
> -	if (pmc->perf_event)
> -		counter += perf_event_read_value(pmc->perf_event,
> +	if (pmc->perf_event) {
> +		perf_event_read(pmc->perf_event);
> +		counter += perf_event_compute_values(pmc->perf_event,
>  						 &enabled, &running);
> +	}

That's more than a rename, that's a functionality split just like the
previous patch.