linux-kernel - Re: [PATCH v11 04/13] x86/cpufeatures: Add Bandwidth Monitoring Event Configuration feature flag

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Message-ID: <8e9dfbe4-ae16-5813-379e-7a958c90ab92@intel.com>
Date:   Tue, 24 Jan 2023 11:23:26 -0800
From:   Reinette Chatre <reinette.chatre@...el.com>
To:     <babu.moger@....com>, Borislav Petkov <bp@...en8.de>
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Subject: Re: [PATCH v11 04/13] x86/cpufeatures: Add Bandwidth Monitoring Event
 Configuration feature flag

Hi Babu,

On 1/24/2023 11:03 AM, Moger, Babu wrote:
> 
> Yes. It is available.  But, the feature BMEC is not explicitly available.

I think your addition [1] to the resctrl documentation explains
well how user space can determine which parts of BMEC are available:

		If the system supports Bandwidth Monitoring Event
		Configuration (BMEC), then the bandwidth events will
		be configurable. The output will be::

			# cat /sys/fs/resctrl/info/L3_MON/mon_features
			llc_occupancy
			mbm_total_bytes
			mbm_total_bytes_config
			mbm_local_bytes
			mbm_local_bytes_config


Reinette

[1] https://lore.kernel.org/lkml/20230113152039.770054-14-babu.moger@amd.com/