Allow for adjustable OOM score on instances

[SpiffyEight77]

Description

• Allow for adjustable OOM score on instances
• close Allow for adjustable OOM score on instances #2116

Test

Restricted project

incus project create restricted-project --config restricted=true
incus project switch restricted-project
incus launch images:ubuntu/22.04 restricted-vm --vm
incus list
+---------------+---------+------+------+-----------------+-----------+
|     NAME      |  STATE  | IPV4 | IPV6 |      TYPE       | SNAPSHOTS |
+---------------+---------+------+------+-----------------+-----------+
| restricted-vm | RUNNING |      |      | VIRTUAL-MACHINE | 0         |
+---------------+---------+------+------+-----------------+-----------+

incus config set restricted-vm limits.memory.oom_priority=100
Error: Failed checking if instance update allowed: Use of low-level config "limits.memory.oom_priority" on virtual-machine "restricted-vm" of project "restricted-project" is forbidden

Normal project

incus launch images:ubuntu/22.04 normal-container
Launching normal-container
incus launch images:ubuntu/22.04 normal-vm --vm
Launching normal-vm
incus ls
+------------------+---------+----------------------+------------------------------------------------+-----------------+-----------+
|       NAME       |  STATE  |         IPV4         |                      IPV6                      |      TYPE       | SNAPSHOTS |
+------------------+---------+----------------------+------------------------------------------------+-----------------+-----------+
| normal-container | RUNNING | 10.222.75.245 (eth0) | fd42:7a1c:a30e:915e:1266:6aff:fe45:893f (eth0) | CONTAINER       | 0         |
+------------------+---------+----------------------+------------------------------------------------+-----------------+-----------+
| normal-vm        | RUNNING |                      | fd42:7a1c:a30e:915e:1266:6aff:fe55:73fb (eth0) | VIRTUAL-MACHINE | 0         |
+------------------+---------+----------------------+------------------------------------------------+-----------------+-----------+

incus config set normal-container limits.memory.oom_priority=100
cat /proc/$(incus info normal-container | grep -i "pid:" | awk '{print $2}')/oom_score_adj
100

incus config set normal-container limits.memory.oom_priority=1000
cat /proc/$(incus info normal-container | grep -i "pid:" | awk '{print $2}')/oom_score_adj
1000

incus config set normal-vm limits.memory.oom_priority=100
cat /proc/$(incus info normal-vm | grep -i "pid:" | awk '{print $2}')/oom_score_adj
100

incus config set normal-vm limits.memory.oom_priority=1000
cat /proc/$(incus info normal-vm | grep -i "pid:" | awk '{print $2}')/oom_score_adj
1000

[stgraber]

Sorry for the delay, had a busy couple of weeks, going to be reviewing this one now.