Re: [PATCH v2 32/45] arm_mpam: resctrl: Add resctrl_arch_config_cntr() for ABMC use

Jonathan Cameron
2026-01-06T14:33:57Z

On Fri, 19 Dec 2025 18:11:34 +0000
Ben Horgan <ben.horgan@arm.com> wrote:

> From: James Morse <james.morse@arm.com>
>
> ABMC has a helper resctrl_arch_config_cntr() for changing the mapping
> between 'cntr_id' and a CLOSID/RMID pair.
>
> Add the helper.
>
> For MPAM this is done by updating the mon->mbwu_idx_to_mon[] array, and as
> usual CDP means it needs doing in three different ways.
>
> Signed-off-by: James Morse <james.morse@arm.com>
> Signed-off-by: Ben Horgan <ben.horgan@arm.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

> ---
> drivers/resctrl/mpam_resctrl.c | 37 ++++++++++++++++++++++++++++++++++
> 1 file changed, 37 insertions(+)
>
> diff --git a/drivers/resctrl/mpam_resctrl.c b/drivers/resctrl/mpam_resctrl.c
> index e96d320c219c..328a81ab68b4 100644
> --- a/drivers/resctrl/mpam_resctrl.c
> +++ b/drivers/resctrl/mpam_resctrl.c
> @@ -765,6 +765,43 @@ static void mpam_resctrl_pick_counters(void)
> mpam_resctrl_counters[QOS_L3_MBM_TOTAL_EVENT_ID].class);
> }
>
> +static void __config_cntr(struct mpam_resctrl_mon *mon, u32 cntr_id,
> + enum resctrl_conf_type cdp_type, u32 closid, u32 rmid,
> + bool assign)
> +{
> + u32 mbwu_idx, mon_idx = resctrl_get_config_index(cntr_id, cdp_type);
> +
> + closid = resctrl_get_config_index(closid, cdp_type);
> + mbwu_idx = resctrl_arch_rmid_idx_encode(closid, rmid);
> + WARN_ON_ONCE(mon_idx > l3_num_allocated_mbwu);
> +
> + if (assign)
> + mon->mbwu_idx_to_mon[mbwu_idx] = mon->assigned_counters[mon_idx];
> + else
> + mon->mbwu_idx_to_mon[mbwu_idx] = -1;
> +}