runc/libcontainer/cgroups/fs2/memory.go

120 lines
3.0 KiB
Go

// +build linux
package fs2
import (
"bufio"
"os"
"path/filepath"
"strconv"
"strings"
"github.com/opencontainers/runc/libcontainer/cgroups"
"github.com/opencontainers/runc/libcontainer/cgroups/fscommon"
"github.com/opencontainers/runc/libcontainer/configs"
"github.com/pkg/errors"
)
// numToStr converts an int64 value to a string for writing to a
// cgroupv2 files with .min, .max, .low, or .high suffix.
// Negative values are converted to "max" for cgroupv1 compatibility
// (which used to write -1 to remove the limit).
func numToStr(value int64) (ret string) {
if value > 0 {
ret = strconv.FormatInt(value, 10)
} else if value < 0 {
ret = "max"
} else {
ret = ""
}
return ret
}
func setMemory(dirPath string, cgroup *configs.Cgroup) error {
if val := numToStr(cgroup.Resources.MemorySwap); val != "" {
if err := fscommon.WriteFile(dirPath, "memory.swap.max", val); err != nil {
return err
}
}
if val := numToStr(cgroup.Resources.Memory); val != "" {
if err := fscommon.WriteFile(dirPath, "memory.max", val); err != nil {
return err
}
}
// cgroup.Resources.KernelMemory is ignored
if val := numToStr(cgroup.Resources.MemoryReservation); val != "" {
if err := fscommon.WriteFile(dirPath, "memory.low", val); err != nil {
return err
}
}
return nil
}
func statMemory(dirPath string, stats *cgroups.Stats) error {
// Set stats from memory.stat.
statsFile, err := os.Open(filepath.Join(dirPath, "memory.stat"))
if err != nil {
return err
}
defer statsFile.Close()
sc := bufio.NewScanner(statsFile)
for sc.Scan() {
t, v, err := fscommon.GetCgroupParamKeyValue(sc.Text())
if err != nil {
return errors.Wrapf(err, "failed to parse memory.stat (%q)", sc.Text())
}
stats.MemoryStats.Stats[t] = v
}
stats.MemoryStats.Cache = stats.MemoryStats.Stats["cache"]
memoryUsage, err := getMemoryDataV2(dirPath, "")
if err != nil {
return err
}
stats.MemoryStats.Usage = memoryUsage
swapUsage, err := getMemoryDataV2(dirPath, "swap")
if err != nil {
return err
}
stats.MemoryStats.SwapUsage = swapUsage
stats.MemoryStats.UseHierarchy = true
return nil
}
func getMemoryDataV2(path, name string) (cgroups.MemoryData, error) {
memoryData := cgroups.MemoryData{}
moduleName := "memory"
if name != "" {
moduleName = strings.Join([]string{"memory", name}, ".")
}
usage := strings.Join([]string{moduleName, "current"}, ".")
limit := strings.Join([]string{moduleName, "max"}, ".")
value, err := fscommon.GetCgroupParamUint(path, usage)
if err != nil {
if moduleName != "memory" && os.IsNotExist(err) {
return cgroups.MemoryData{}, nil
}
return cgroups.MemoryData{}, errors.Wrapf(err, "failed to parse %s", usage)
}
memoryData.Usage = value
value, err = fscommon.GetCgroupParamUint(path, limit)
if err != nil {
if moduleName != "memory" && os.IsNotExist(err) {
return cgroups.MemoryData{}, nil
}
return cgroups.MemoryData{}, errors.Wrapf(err, "failed to parse %s", limit)
}
memoryData.Limit = value
return memoryData, nil
}