Re: [PATCH v2 12/17] coresight: trbe: Add a helper to fetch cpudata from perf handle

From: Mathieu Poirier
Date: Mon Oct 04 2021 - 13:42:45 EST


On Tue, Sep 21, 2021 at 02:41:16PM +0100, Suzuki K Poulose wrote:
> Add a helper to get the CPU specific data for TRBE instance, from
> a given perf handle. This also adds extra checks to make sure that
> the event associated with the handle is "bound" to the CPU and is
> active on the TRBE.
>
> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
> Cc: Mike Leach <mike.leach@xxxxxxxxxx>
> Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> Cc: Leo Yan <leo.yan@xxxxxxxxxx>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> ---
> drivers/hwtracing/coresight/coresight-trbe.c | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c
> index 983dd5039e52..797d978f9fa7 100644
> --- a/drivers/hwtracing/coresight/coresight-trbe.c
> +++ b/drivers/hwtracing/coresight/coresight-trbe.c
> @@ -268,6 +268,15 @@ static unsigned long trbe_snapshot_offset(struct perf_output_handle *handle)
> return buf->nr_pages * PAGE_SIZE;
> }
>
> +static inline struct trbe_cpudata *
> +trbe_handle_to_cpudata(struct perf_output_handle *handle)
> +{
> + struct trbe_buf *buf = etm_perf_sink_config(handle);
> +
> + BUG_ON(!buf || !buf->cpudata);
> + return buf->cpudata;
> +}
> +
> /*
> * TRBE Limit Calculation
> *
> @@ -533,8 +542,7 @@ static enum trbe_fault_action trbe_get_fault_act(struct perf_output_handle *hand
> {
> int ec = get_trbe_ec(trbsr);
> int bsc = get_trbe_bsc(trbsr);
> - struct trbe_buf *buf = etm_perf_sink_config(handle);
> - struct trbe_cpudata *cpudata = buf->cpudata;
> + struct trbe_cpudata *cpudata = trbe_handle_to_cpudata(handle);

There is two other places where this pattern is present: is_perf_trbe() and
__trbe_normal_offset().

I have to stop here for today. More comments tomorrow.

Thanks,
Mathieu

>
> WARN_ON(is_trbe_running(trbsr));
> if (is_trbe_trg(trbsr) || is_trbe_abort(trbsr))
> --
> 2.24.1
>