Re: [PATCH v11 11/13] x86/resctrl: Add interface to write mbm_total_bytes_config

From: Reinette Chatre
Date: Wed Jan 11 2023 - 17:05:36 EST


Hi Babu,

On 1/9/2023 8:44 AM, Babu Moger wrote:
> The event configuration for mbm_total_bytes can be changed by the user by
> writing to the file /sys/fs/resctrl/info/L3_MON/mbm_total_bytes_config.
>
> The event configuration settings are domain specific and affect all the
> CPUs in the domain.
>
> Following are the types of events supported:
>
> ==== ===========================================================
> Bits Description
> ==== ===========================================================
> 6 Dirty Victims from the QOS domain to all types of memory
> 5 Reads to slow memory in the non-local NUMA domain
> 4 Reads to slow memory in the local NUMA domain
> 3 Non-temporal writes to non-local NUMA domain
> 2 Non-temporal writes to local NUMA domain
> 1 Reads to memory in the non-local NUMA domain
> 0 Reads to memory in the local NUMA domain
> ==== ===========================================================
>
> For example:
> To change the mbm_total_bytes to count only reads on domain 0, the bits
> 0, 1, 4 and 5 needs to be set, which is 110011b (in hex 0x33). Run the
> command.
> $echo 0=0x33 > /sys/fs/resctrl/info/L3_MON/mbm_total_bytes_config
>
> To change the mbm_total_bytes to count all the slow memory reads on
> domain 1, the bits 4 and 5 needs to be set which is 110000b (in hex 0x30).
> Run the command.
> $echo 1=0x30 > /sys/fs/resctrl/info/L3_MON/mbm_total_bytes_config
>
> Signed-off-by: Babu Moger <babu.moger@xxxxxxx>

Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>

Thank you

Reinette