context: kubernetes/kubernetes#68478
The inotify code was removed from golang.org/x/exp several years ago. Therefore
importing it from that path prevents downstream consumers from using any module
that makes use of more recent features of golang.org/x/exp.
Given that this code is by definition frozen and that the long term path should
be to migrate to fsnotify, replacing the current code by an identical standalone
copy doesn't have maintenance cost, and will unlock other activities for
kubernetes for example.
PerDiskStats reported from cgroups were not being surfaced into
prometheus. In order to properly correlate the metrics, we need to
assign a device label to each metric (which is the FS or device path).
Since blkio cgroup tracks devices, we create a synthetic device
`/dev/NAME` for the metric.
Assign a Device label to each PerDiskStat for the handlers up front, and
then surface the PerDiskStat values into the prometheus metrics. Report
two new metrics - total bytes read and total bytes written.
- Pull out the root container cases, since they're only relevant in the
raw container handler
- Pass parameters rather than depending on AbstractContainerInterface
