linux-kernel - Re: [PATCH v12 18/26] x86/resctrl: Add default MBM event configurations for mbm_cntr

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Message-ID: <5cbd73c9-421c-4147-9922-29123f011882@intel.com>
Date: Wed, 16 Apr 2025 09:18:14 -0700
From: Reinette Chatre <reinette.chatre@...el.com>
To: <babu.moger@....com>, <tony.luck@...el.com>, <peternewman@...gle.com>
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Subject: Re: [PATCH v12 18/26] x86/resctrl: Add default MBM event
 configurations for mbm_cntr_assign mode

Hi Babu,

On 4/15/25 11:48 AM, Moger, Babu wrote:
> Hi Reinette,
> 
> On 4/11/25 16:44, Reinette Chatre wrote:
>> Hi Babu,
>>
>> On 4/3/25 5:18 PM, Babu Moger wrote:
>>> By default, each resctrl group supports two MBM events: mbm_total_bytes
>>> and mbm_local_bytes. To maintain the same level of support, two default
>>> MBM configurations are added. These configurations will initially be used
>>> to set up the counters upon mounting, while users will have the option to
>>> modify them as needed.
>>
>> This jumps in quite fast by stating that MBM configurations are added but
>> there is no definition of what an MBM configuration is.
> 
> How about this?
> 
> 
> By default, each resctrl group supports two MBM events: mbm_total_bytes
> and mbm_local_bytes. These represent total and local memory bandwidth
> monitoring, respectively. Each event corresponds to a specific MBM
> configuration. Use these default configurations to set up the counters
> during mount. Allow users to modify the configurations as needed after
> initialization.

I am still missing a definition of "MBM configuration". How about:

"Each event corresponds to a specific MBM configuration." -> "Each event
corresponds to an MBM configuration that specifies the bandwidth sources
tracked by the event."

...

>>
>> There seems more and more overlap with Tony's RMID work. Did you get a
>> chance to look at that?
> 
> Looked little bit. Will have look bit closer again.

I'll study that series next to catch up with Tony's plans.

Reinette