Re: [PATCH 3/8] selftests/resctrl: Support multiple events associated with iMC

[Reinette Chatre <reinette.chatre@intel.com>]

Hi Zide,

On 2/11/26 3:37 PM, Chen, Zide wrote:
> 
> 
> On 2/10/2026 8:50 AM, Reinette Chatre wrote:
>> The resctrl selftests discover needed parameters to perf_event_open() via
>> sysfs. The PMU associated with every memory controller (iMC) is discovered
>> via the /sys/bus/event_source/devices/uncore_imc_N/type file while
>> the read memory bandwidth event type and umask is discovered via
>> /sys/bus/event_source/devices/uncore_imc_N/events/cas_count_read.
>>
>> Newer systems may have multiple events that expose read memory bandwidth.
>> For example,
>>  /sys/bus/event_source/devices/uncore_imc_N/events/cas_count_read_sch0
>>  /sys/bus/event_source/devices/uncore_imc_N/events/cas_count_read_sch1
>>
>> Support parsing of iMC PMU properties when the PMU may have multiple events
>> to measure read memory bandwidth. The PMU only needs to be discovered once.
>> Split the parsing of event details from actual PMU discovery in order to
>> loop over all events associated with the PMU. Match all events with the
>> cas_count_read prefix instead of requiring there to be one file with that
>> name.
>>
>> Make the parsing code more robust. With strings passed around to create
>> needed paths, use snprintf() instead of sprintf() to ensure there is
>> always enough space to create the path. Ensure there is enough room in
>> imc_counters_config[] before attempting to add an entry.
>>
>> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
> 
> Reviewed-by: Zide Chen <zide.chen@intel.com>

Thank you very much for taking a look at this work and especially thanks
for creating the perf changes that they depend on to fix these tests.

Reinette