RE: [PATCH 3/7] x86/resctrl: Add a new node-scoped resource to rdt_resources_all[]

["Luck, Tony" <tony.luck@intel.com>]

>> +	[RDT_RESOURCE_NODE] =
>> +	{
>> +		.r_resctrl = {
>> +			.rid			= RDT_RESOURCE_NODE,
>> +			.name			= "L3",

> "L3" was named as RDT_RESOURCE_L3 already. The duplicate name here may
> cause duplicate file names in info dir. Maybe rename it as "L3_NODE"?

I thought the same, and my first implementation used a different string here (I picked
"NODE" rather than "L3_NODE").

But my testers complained that this broke all their existing infrastructure that reads
cache occupancy and memory bandwidth. This string is not just used in the info/
directory, it is also the basis for the directory names in mon_data/

$ tree /sys/fs/resctrl/mon_data
/sys/fs/resctrl/mon_data
├── mon_L3_00
│   ├── llc_occupancy
│   ├── mbm_local_bytes
│   └── mbm_total_bytes
├── mon_L3_01
│   ├── llc_occupancy
│   ├── mbm_local_bytes
│   └── mbm_total_bytes
├── mon_L3_02
│   ├── llc_occupancy
│   ├── mbm_local_bytes
│   └── mbm_total_bytes
└── mon_L3_03
    ├── llc_occupancy
    ├── mbm_local_bytes
    └── mbm_total_bytes

The name using "L3" is still appropriate and accurate.

There isn't a "duplicate file names" problem in the info/ directory because a system
either has SNC disabled, and uses the L3-scoped resource, or has SNC enabled and
uses the node-scoped resource.

-Tony