Merge pull request #55188 from mindprince/accelerator-monitoring

Automatic merge from submit-queue (batch tested with PRs 55798, 49579, 54862, 55188, 51990). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Add monitoring support for hardware accelerators

Currently only NVIDIA GPU monitoring is implemented.

Feature repo issue: https://github.com/kubernetes/features/issues/369
cAdvisor PR: https://github.com/google/cadvisor/pull/1762

/kind feature
/sig node
/sig instrumentation
/area hw-accelerators

**Release note**:
```release-note
Kubelet now exposes metrics for NVIDIA GPUs attached to the containers.
```

Kubernetes-commit: 779105673ab2f00af9e02dc9ac3c6413588aeae4

vendor/golang.org/x/sys/unix/syscall_bsd.go

@@ -34,7 +34,7 @@ func Getgroups() (gids []int, err error) {
 		return nil, nil
 	}
 
-	// Sanity check group count.  Max is 16 on BSD.
+	// Sanity check group count. Max is 16 on BSD.
 	if n < 0 || n > 1000 {
 		return nil, EINVAL
 	}
@@ -607,6 +607,15 @@ func Futimes(fd int, tv []Timeval) error {
 
 //sys	fcntl(fd int, cmd int, arg int) (val int, err error)
 
+//sys   poll(fds *PollFd, nfds int, timeout int) (n int, err error)
+
+func Poll(fds []PollFd, timeout int) (n int, err error) {
+	if len(fds) == 0 {
+		return poll(nil, 0, timeout)
+	}
+	return poll(&fds[0], len(fds), timeout)
+}
+
 // TODO: wrap
 //	Acct(name nil-string) (err error)
 //	Gethostuuid(uuid *byte, timeout *Timespec) (err error)