containerd/vendor/github.com/opencontainers/runc/libcontainer/cgroups/fs/pids.go
Markus Lehtonen ed47d6ba76 cri: implement RuntimeConfig rpc
The rpc only reports one field, i.e. the cgroup driver, to kubelet.
Containerd determines the effective cgroup driver by looking at all
runtime handlers, starting from the default runtime handler (the rest in
alphabetical order), and returning the cgroup driver setting of the
first runtime handler that supports one. If no runtime handler supports
cgroup driver (i.e. has a config option for it) containerd falls back to
auto-detection, returning systemd if systemd is running and cgroupfs
otherwise.

This patch implements the CRI server side of Kubernetes KEP-4033:
https://github.com/kubernetes/enhancements/tree/master/keps/sig-node/4033-group-driver-detection-over-cri

Signed-off-by: Markus Lehtonen <markus.lehtonen@intel.com>
2023-07-28 13:50:43 +03:00

63 lines
1.3 KiB
Go

package fs
import (
"math"
"strconv"
"github.com/opencontainers/runc/libcontainer/cgroups"
"github.com/opencontainers/runc/libcontainer/cgroups/fscommon"
"github.com/opencontainers/runc/libcontainer/configs"
)
type PidsGroup struct{}
func (s *PidsGroup) Name() string {
return "pids"
}
func (s *PidsGroup) Apply(path string, _ *configs.Resources, pid int) error {
return apply(path, pid)
}
func (s *PidsGroup) Set(path string, r *configs.Resources) error {
if r.PidsLimit != 0 {
// "max" is the fallback value.
limit := "max"
if r.PidsLimit > 0 {
limit = strconv.FormatInt(r.PidsLimit, 10)
}
if err := cgroups.WriteFile(path, "pids.max", limit); err != nil {
return err
}
}
return nil
}
func (s *PidsGroup) GetStats(path string, stats *cgroups.Stats) error {
if !cgroups.PathExists(path) {
return nil
}
current, err := fscommon.GetCgroupParamUint(path, "pids.current")
if err != nil {
return err
}
max, err := fscommon.GetCgroupParamUint(path, "pids.max")
if err != nil {
return err
}
// If no limit is set, read from pids.max returns "max", which is
// converted to MaxUint64 by GetCgroupParamUint. Historically, we
// represent "no limit" for pids as 0, thus this conversion.
if max == math.MaxUint64 {
max = 0
}
stats.PidsStats.Current = current
stats.PidsStats.Limit = max
return nil
}