pkg/libcontainer/cgroups/fs/utils.go
Vishnu Kannan 8610e96a03 Adding percpu usage to cgroup stats reported by libcontainer.
Docker-DCO-1.1-Signed-off-by: Vishnu Kannan <vishnuk@google.com> (github: vishh)
2014-06-02 06:56:15 +00:00

40 lines
1 KiB
Go

package fs
import (
"errors"
"fmt"
"io/ioutil"
"path/filepath"
"strconv"
"strings"
)
var (
ErrNotSupportStat = errors.New("stats are not supported for subsystem")
ErrNotValidFormat = errors.New("line is not a valid key value format")
)
// Parses a cgroup param and returns as name, value
// i.e. "io_service_bytes 1234" will return as io_service_bytes, 1234
func getCgroupParamKeyValue(t string) (string, uint64, error) {
parts := strings.Fields(t)
switch len(parts) {
case 2:
value, err := strconv.ParseUint(parts[1], 10, 64)
if err != nil {
return "", 0, fmt.Errorf("Unable to convert param value to uint64: %s", err)
}
return parts[0], value, nil
default:
return "", 0, ErrNotValidFormat
}
}
// Gets a single int64 value from the specified cgroup file.
func getCgroupParamInt(cgroupPath, cgroupFile string) (uint64, error) {
contents, err := ioutil.ReadFile(filepath.Join(cgroupPath, cgroupFile))
if err != nil {
return 0, err
}
return strconv.ParseUint(strings.TrimSpace(string(contents)), 10, 64)
}