Re: [PATCH v5 16/25] PM / devfreq: rockchip-dfi: Add perf support

[Sascha Hauer]

On Wed, May 24, 2023 at 10:31:44AM +0200, Sascha Hauer wrote:
> +static int rockchip_ddr_perf_event_add(struct perf_event *event, int flags)
> +{
> +	struct rockchip_dfi *dfi = container_of(event->pmu, struct rockchip_dfi, pmu);
> +
> +	dfi->active_events++;
> +
> +	if (dfi->active_events == 1)

We need to initialize dfi->last_perf_count here:

		rockchip_dfi_read_counters(dfi, &dfi->last_perf_count);

dfi->last_perf_count contains the start values for the counters and
without initializing this the u32 counter overflows are not correctly
handled.

Sascha


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