Re: [PATCH 17/33] arm_mpam: Merge supported features during mpam_enable() into mpam_class

Gavin Shan
2025-11-09T21:59:50Z

On 11/7/25 10:34 PM, Ben Horgan wrote:
> From: James Morse <james.morse@arm.com>
>
> To make a decision about whether to expose an mpam class as
> a resctrl resource we need to know its overall supported
> features and properties.
>
> Once we've probed all the resources, we can walk the tree
> and produce overall values by merging the bitmaps. This
> eliminates features that are only supported by some MSC
> that make up a component or class.
>
> If bitmap properties are mismatched within a component we
> cannot support the mismatched feature.
>
> Care has to be taken as vMSC may hold mismatched RIS.
>
> Signed-off-by: James Morse <james.morse@arm.com>
> Reviewed-by: Ben Horgan <ben.horgan@arm.com>
> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
> Tested-by: Fenghua Yu <fenghuay@nvidia.com>
> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
> Tested-by: Peter Newman <peternewman@google.com>
> Signed-off-by: Ben Horgan <ben.horgan@arm.com>
> ---
> drivers/resctrl/mpam_devices.c | 214 ++++++++++++++++++++++++++++++++
> drivers/resctrl/mpam_internal.h | 3 +
> 2 files changed, 217 insertions(+)
>

Reviewed-by: Gavin Shan <gshan@redhat.com>