Re: [PATCH v7 5/8] perf: imx_perf: fix counter start and config sequence

[Frank Li]

On Fri, Mar 15, 2024 at 05:55:52PM +0800, Xu Yang wrote:
> In current driver, the counter will start firstly and then be configured.
> This sequence is not correct for AXI filter events since the correct
> AXI_MASK and AXI_ID are not set yet. Then the results may be inaccurate.
> 
> Signed-off-by: Xu Yang <xu.yang_2@xxxxxxx>

This one should be bug fix. Can you add fixes tag?

> 
> ---
> Changes in v5:
>  - new patch
> Changes in v6:
>  - no changes
> Changes in v7:
>  - no changes
> ---
>  drivers/perf/fsl_imx9_ddr_perf.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/perf/fsl_imx9_ddr_perf.c b/drivers/perf/fsl_imx9_ddr_perf.c
> index 5537f4e07852..c99c43b214cb 100644
> --- a/drivers/perf/fsl_imx9_ddr_perf.c
> +++ b/drivers/perf/fsl_imx9_ddr_perf.c
> @@ -523,12 +523,12 @@ static int ddr_perf_event_add(struct perf_event *event, int flags)
>  	hwc->idx = counter;
>  	hwc->state |= PERF_HES_STOPPED;
>  
> -	if (flags & PERF_EF_START)
> -		ddr_perf_event_start(event, flags);
> -
>  	/* read trans, write trans, read beat */
>  	imx93_ddr_perf_monitor_config(pmu, event_id, counter, cfg1, cfg2);
>  
> +	if (flags & PERF_EF_START)
> +		ddr_perf_event_start(event, flags);
> +
>  	return 0;
>  }
>  
> -- 
> 2.34.1
>