Merge pull request #34385 from m1093782566/m109-kube-proxy-sys
Automatic merge from submit-queue
Generify kube-proxy conntracker setmax() and refactor util/sysctl
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**What this PR does / why we need it**:
Fix Kube-proxy `conntrack.go` **TODO** [here](https://github.com/kubernetes/kubernetes/blob/master/cmd/kube-proxy/app/conntrack.go#L56). This PR consists of two parts:
* Generify kube-proxy `realConntracker.SetMax(int)`
That is, change
`ioutil.WriteFile("/sys/module/nf_conntrack/parameters/hashsize", []byte(strconv.Itoa(max/4)), 0640)`
to
`sysctl.New().WriteValue("/sys/module/nf_conntrack/parameters/hashsize", max/4)`
* Refactor `sysctl.SetSysctl()` and `sysctl.GetSysctl()` to `WriteValue(path string, value string) error` and `GetValue(path value) (error, string)`
c07c73efbb