[PATCH v6 32/40] arm_mpam: resctrl: Add empty definitions for assorted resctrl functions

[Gavin Shan]

On 3/14/26 12:46 AM, Ben Horgan wrote:
> From: James Morse <james.morse at arm.com>
> 
> A few resctrl features and hooks need to be provided, but aren't needed or
> supported on MPAM platforms.
> 
> resctrl has individual hooks to separately enable and disable the
> closid/partid and rmid/pmg context switching code. For MPAM this is all the
> same thing, as the value in struct task_struct is used to cache the value
> that should be written to hardware. arm64's context switching code is
> enabled once MPAM is usable, but doesn't touch the hardware unless the
> value has changed.
> 
> For now event configuration is not supported, and can be turned off by
> returning 'false' from resctrl_arch_is_evt_configurable().
> 
> The new io_alloc feature is not supported either, always return false from
> the enable helper to indicate and fail the enable.
> 
> Add this, and empty definitions for the other hooks.
> 
> Tested-by: Gavin Shan <gshan at redhat.com>
> Tested-by: Shaopeng Tan <tan.shaopeng at jp.fujitsu.com>
> Tested-by: Peter Newman <peternewman at google.com>
> Tested-by: Zeng Heng <zengheng4 at huawei.com>
> Tested-by: Punit Agrawal <punit.agrawal at oss.qualcomm.com>
> Reviewed-by: Zeng Heng <zengheng4 at huawei.com>
> Reviewed-by: Shaopeng Tan <tan.shaopeng at jp.fujitsu.com>
> Reviewed-by: Jonathan Cameron <jonathan.cameron at huawei.com>
> Signed-off-by: James Morse <james.morse at arm.com>
> Signed-off-by: Ben Horgan <ben.horgan at arm.com>
> ---
> Changes since v3:
> Add resctrl_arch_pre_mount() {}
> resctrl_arch_reset_rmid_all() signature update
> add stubs for abmc
> keep empty definitions together
> 
> Changes since v5:
> Add resctrl_arch_reset_rmid() since mbwu will always use abmc
> ---
>   drivers/resctrl/mpam_resctrl.c | 65 ++++++++++++++++++++++++++++++++++
>   include/linux/arm_mpam.h       |  9 +++++
>   2 files changed, 74 insertions(+)
> 
Reviewed-by: Gavin Shan <gshan at redhat.com>