linux-kernel - Re: [PATCH v2 32/45] arm_mpam: resctrl: Add resctrl_arch_config

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20260106143349.000007f3@huawei.com>
Date: Tue, 6 Jan 2026 14:33:49 +0000
From: Jonathan Cameron <jonathan.cameron@...wei.com>
To: Ben Horgan <ben.horgan@....com>
CC: <amitsinght@...vell.com>, <baisheng.gao@...soc.com>,
	<baolin.wang@...ux.alibaba.com>, <carl@...amperecomputing.com>,
	<dave.martin@....com>, <david@...nel.org>, <dfustini@...libre.com>,
	<fenghuay@...dia.com>, <gshan@...hat.com>, <james.morse@....com>,
	<kobak@...dia.com>, <lcherian@...vell.com>,
	<linux-arm-kernel@...ts.infradead.org>, <linux-kernel@...r.kernel.org>,
	<peternewman@...gle.com>, <punit.agrawal@....qualcomm.com>,
	<quic_jiles@...cinc.com>, <reinette.chatre@...el.com>,
	<rohit.mathew@....com>, <scott@...amperecomputing.com>,
	<sdonthineni@...dia.com>, <tan.shaopeng@...itsu.com>,
	<xhao@...ux.alibaba.com>, <catalin.marinas@....com>, <will@...nel.org>,
	<corbet@....net>, <maz@...nel.org>, <oupton@...nel.org>,
	<joey.gouly@....com>, <suzuki.poulose@....com>, <kvmarm@...ts.linux.dev>
Subject: Re: [PATCH v2 32/45] arm_mpam: resctrl: Add
 resctrl_arch_config_cntr() for ABMC use

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

> From: James Morse <james.morse@....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@....com>
> Signed-off-by: Ben Horgan <ben.horgan@....com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@...wei.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;
> +}