[PATCH] coresight: etm4x: Don't bother the user with nonessential log message

[James Clark]

On 03/08/2023 07:22, Tian Tao wrote:
> Each cpu will print the following log when initializing
> ETM "coresight etm1: CPU1: etm v4.5 initialized", if there are a lot
> of cpus, e.g. 128. there will be a screen full of this log. replace
> dev_info with dev_dbg prints only when needed.
> 
> Signed-off-by: Tian Tao <tiantao6 at hisilicon.com>
> ---
>  drivers/hwtracing/coresight/coresight-etm4x-core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> index 7e307022303a..7b51e8594fd5 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> @@ -2033,7 +2033,7 @@ static int etm4_add_coresight_dev(struct etm4_init_arg *init_arg)
>  
>  	etmdrvdata[drvdata->cpu] = drvdata;
>  
> -	dev_info(&drvdata->csdev->dev, "CPU%d: %s v%d.%d initialized\n",
> +	dev_dbg(&drvdata->csdev->dev, "CPU%d: %s v%d.%d initialized\n",
>  		 drvdata->cpu, type_name, major, minor);
>  
>  	if (boot_enable) {

Hi Tian,

Do you think it's worth keeping a single info printout as well as the
per-cpu dbg one? I'm thinking that the only way to get these messages
now is to boot with debug printing on, and that is quite noisy. Because
it's too late to use debugfs to enable just coresight debug messages
after booting. So something like this:

  dev_info_once(&drvdata->csdev->dev, "%s v%d.%d initialized\n",

Also I still get this printed out per-cpu, which is from
coresight-syscfg.c. Do you not see this? Might be worth doing the same
change there.

  CSCFG registered etm0
  CSCFG registered etm1
  CSCFG registered etm2
  CSCFG registered etm3

Thanks
James