Re: [PATCH v3 02/38] x86/resctrl: Add a helper to avoid reaching into the arch code resource list

From: Reinette Chatre
Date: Fri Jun 28 2024 - 12:42:29 EST


Hi James,

On 6/14/24 7:59 AM, James Morse wrote:
Resctrl occasionally wants to know something about a specific resource,
in these cases it reaches into the arch code's rdt_resources_all[]
array.

Once the filesystem parts of resctrl are moved to /fs/, this means it
will need visibility of the architecture specific struct
rdt_hw_resource definition, and the array of all resources. All
architectures would also need a r_resctrl member in this struct.

Instead, abstract this via a helper to allow architectures to do
different things here. Move the level enum to the resctrl header and
add a helper to retrieve the struct rdt_resource by 'rid'.

resctrl_arch_get_resource() should not return NULL for any value in
the enum, it may instead return a dummy resource that is
!alloc_enabled && !mon_enabled.

Co-developed-by: Dave Martin <Dave.Martin@xxxxxxx>
Signed-off-by: Dave Martin <Dave.Martin@xxxxxxx>
Signed-off-by: James Morse <james.morse@xxxxxxx>
Tested-by: Peter Newman <peternewman@xxxxxxxxxx>
Tested-by: Shaopeng Tan <tan.shaopeng@xxxxxxxxxxxxxx>
---

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

Reinette