scx_layered: Add user and group layers

[hodgesds]

Add a layer match based on either the effective user id or the effective group id. This allows for creating layers for individual users or groups.

Test:

$ id
uid=224791(hodgesd) gid=100(users) groups=100(users)

config:

$ cat user.json 
[{
  "name":"hodgesd",
  "comment":"hodgesd user",
  "matches":[
     [{"UIDEquals":224791}]
  ],
  "kind": {
    "Open":{
      "min_exec_us":0,
      "preempt": true,
      "exclusive": true
     }
  }
},
{
  "name":"normal",
  "comment":"the rest",
  "matches":[[]],
  "kind":{
    "Open": {
      "min_exec_us":0,
      "preempt":false,
      "exclusive":false
    }
  }
}]

scx_layered has layers for my user:

18:56:35 [INFO] excl_coll= 0.00 excl_preempt= 0.00 excl_idle= 0.00 excl_wakeup= 0.02
18:56:35 [INFO]   hodgesd: util/frac=    9.8/  5.5 load/frac=      9.6:  3.2 tasks=   355
18:56:35 [INFO]            tot=    621 local=94.85 wake/exp/last/reenq= 3.70/ 0.48/ 0.97/ 0.00
18:56:35 [INFO]            keep/max/busy= 0.97/ 0.00/ 0.00 kick= 0.48 yield/ign= 0.00/    0 
18:56:35 [INFO]            open_idle= 0.00 mig=17.23 affn_viol= 0.00
18:56:35 [INFO]            preempt/first/idle/fail= 0.16/ 0.00/ 3.54/ 0.00 min_exec= 0.00/   0.00ms
18:56:35 [INFO]            cpus=  0 [  0,  0] 00000000 00000000 00000000
18:56:35 [INFO]            excl_coll= 0.00 excl_preempt= 0.00
18:56:35 [INFO]   normal : util/frac=  167.2/ 94.5 load/frac=    288.6: 96.8 tasks=  3203
18:56:35 [INFO]            tot=  26836 local=95.83 wake/exp/last/reenq= 1.79/ 0.56/ 1.82/ 0.01
18:56:35 [INFO]            keep/max/busy= 0.28/ 0.00/ 0.00 kick= 0.57 yield/ign= 1.56/    0 
18:56:35 [INFO]            open_idle= 0.00 mig= 6.58 affn_viol= 0.00
18:56:35 [INFO]            preempt/first/idle/fail= 0.00/ 0.00/ 0.00/ 0.00 min_exec= 0.00/   0.00ms
18:56:35 [INFO]            cpus=  0 [  0,  0] 00000000 00000000 00000000

[hodgesds]

should this be UserIdEquals?

[htejun]

Ah, I guess so. If it were me, I'd just do UIDEquls and GIDEquals but either way is fine.

[hodgesds]

I think that's better, let me update.