Re: [RFC PATCH 1/3] fs/resctrl: Add schema_name to struct resctrl_ctrl

[Ben Horgan <ben.horgan@arm.com>]

Hi Drew,

On 22/09/2026 21:15, Drew Fustini wrote:
> On Mon, Sep 21, 2026 at 02:57:00PM +0100, Ben Horgan wrote:
>> In order to properly align the schema in the schemata and size file the
>> maximum of length of all the schema names needs to be
>> known. resctrl_resource_ctrl_max_len() makes this calculation but stops
>> short of actually constructing and storing the schema names. As the schema
>> name is based on the resource name and the schema name with some special
>> cases for legacy controls this leads to a lot of conditional formatting
>> when displaying the schema name.
>>
>> Construct the schema name and save it to struct resctrl when mounting
>> resctrl. This makes displaying the schema name easy whilst control of the
>> naming stays within resctrl.
>>
>> Signed-off-by: Ben Horgan <ben.horgan@arm.com>
>> ---
>>  fs/resctrl/ctrlmondata.c | 51 ++++++-----------------------
>>  fs/resctrl/rdtgroup.c    | 69 +++++++++++++++++++++++++---------------
>>  include/linux/resctrl.h  |  1 +
>>  3 files changed, 55 insertions(+), 66 deletions(-)
>>
>> diff --git a/fs/resctrl/ctrlmondata.c b/fs/resctrl/ctrlmondata.c
> [..]
>> @@ -638,18 +608,17 @@ int rdtgroup_schemata_show(struct kernfs_open_file *of,
>>  	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
>>  		list_for_each_entry(f, &rdt_resource_final_all, list) {
>>  			for_each_enabled_ctrl(ctrl, f->res)
>> -				seq_printf(s, "%s%s%s:uninitialized\n", f->name,
>> -					   resctrl_ctrl_is_default(ctrl) ? "" : "_",
>> -					   resctrl_ctrl_is_default(ctrl) ?
>> -					    "" : resctrl_ctrl_name_str(ctrl->name));
>> +				seq_printf(s, "%*s:uninitialized\n",
>> +					   max_name_width, ctrl->schema_name);
>>  		}
>>  	} else if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
>>  		if (!rdtgrp->plr->d) {
>>  			rdt_last_cmd_puts("Cache domain offline\n");
>>  			ret = -ENODEV;
>>  		} else {
>> -			seq_printf(s, "%s:%d=%x\n",
>> -				   rdtgrp->plr->f->res->name,
>> +			ctrl = resctrl_resource_ctrl_get_default(f->res);
> 
> I think f is only set in the for loops, so should this be
> rdtgrp->plr->f->res instead of f->res?

Yes, it should be. I only ran this on MPAM so didn't encounter this.

Thanks,

Ben

> 
> Thanks,
> Drew