config-linux: clarify the handling of ClosID RDT parameter

An attempt to make the spec easier to interpret by grouping all ClosID
related contraints in one place.

Signed-off-by: Markus Lehtonen <[email protected]>

Author: marquiz

config-linux.md

@@ -530,7 +530,6 @@ If `intelRdt` is not set, the runtime MUST NOT manipulate any `resctrl` pseudo-f
 The following parameters can be specified for the container:
 
 * **`closID`** *(string, OPTIONAL)* - specifies the identity for RDT Class of Service (CLOS).
-    If `closID` is set, runtimes MUST create `closID` directory in a mounted `resctrl` pseudo-filesystem if it doesn't exist. If not set, runtimes MUST use the container ID from [`start`](runtime.md#start) and create the `<container-id>` directory.
 
 * **`l3CacheSchema`** *(string, OPTIONAL)* - specifies the schema for L3 cache id and capacity bitmask (CBM).
     The value SHOULD start with `L3:` and SHOULD NOT contain newlines.
@@ -547,7 +546,11 @@ The following rules on parameters MUST be applied:
 
 * If neither `l3CacheSchema` nor `memBwSchema` is set, runtimes MUST NOT write to `schemata` files in any `resctrl` pseudo-filesystems.
 
-* If `closID` is set, `l3CacheSchema` and/or `memBwSchema` is set, runtimes MUST compare `l3CacheSchema` and/or `memBwSchema` value with `schemata` file, and [generate an error](runtime.md#errors) if doesn't match.
+* If `closID` is not set, runtimes MUST use the container ID from [`start`](runtime.md#start) and create the `<container-id>` directory.
+
+* If `closID` is set, `l3CacheSchema` and/or `memBwSchema` is set
+  * if `closID` directory in a mounted `resctrl` pseudo-filesystem doesn't exist, the runtimes MUST create it.
+  * if `closID` directory in a mounted `resctrl` pseudo-filesystem exists, runtimes MUST compare `l3CacheSchema` and/or `memBwSchema` value with `schemata` file, and [generate an error](runtime.md#errors) if doesn't match.
 
 * If `closID` is set, and neither of `l3CacheSchema` and `memBwSchema` are set, runtime MUST check if corresponding pre-configured directory `closID` is present in mounted `resctrl`. If such pre-configured directory `closID` exists, runtime MUST assign container to this `closID` and [generate an error](runtime.md#errors) if directory does not exist.