Re: [PATCH v5 3/3] perf x86: Exposing an Uncore unit to PMON for Intel Xeon® server platform

[Greg KH]

On Tue, Feb 11, 2020 at 07:15:49PM +0300, roman.sudarikov@xxxxxxxxxxxxxxx wrote:
> +static ssize_t skx_iio_mapping_show(struct device *dev,
> +				struct device_attribute *attr, char *buf)
> +{
> +	struct pmu *pmu = dev_get_drvdata(dev);
> +	struct intel_uncore_pmu *uncore_pmu =
> +		container_of(pmu, struct intel_uncore_pmu, pmu);
> +
> +	struct dev_ext_attribute *ea =
> +		container_of(attr, struct dev_ext_attribute, attr);
> +	long die = (long)ea->var;
> +
> +	return sprintf(buf, "0000:%02x\n", skx_iio_stack(uncore_pmu, die));

If "0000:" is always the "prefix" of the output of this file, why have
it at all as you always know it is there?

What is ever going to cause that to change?

thanks,

greg k-h