Merge pull request opencontainers#2643 from xiaochenshen/rdt-cmt-check

libcontainer/intelrdt: fix CMT feature check

libcontainer/intelrdt/cmt.go

@@ -12,11 +12,13 @@ func IsCMTEnabled() bool {
 func getCMTNumaNodeStats(numaPath string) (*CMTNumaNodeStats, error) {
  stats := &CMTNumaNodeStats{}
 
- llcOccupancy, err := getIntelRdtParamUint(numaPath, "llc_occupancy")
- if err != nil {
- return nil, err
+ if enabledMonFeatures.llcOccupancy {
+ llcOccupancy, err := getIntelRdtParamUint(numaPath, "llc_occupancy")
+ if err != nil {
+ return nil, err
+ }
+ stats.LLCOccupancy = llcOccupancy
  }
- stats.LLCOccupancy = llcOccupancy
 
  return stats, nil
 }

libcontainer/intelrdt/intelrdt.go

@@ -237,16 +237,20 @@ func init() {
  }
  }
 
- if flagsSet.MBMTotal || flagsSet.MBMLocal {
- if _, err := os.Stat(filepath.Join(intelRdtRoot, "info", "L3_MON")); err == nil {
- mbmEnabled = true
- cmtEnabled = true
+ if flagsSet.MBMTotal || flagsSet.MBMLocal || flagsSet.CMT {
+ if _, err := os.Stat(filepath.Join(intelRdtRoot, "info", "L3_MON")); err != nil {
+ return
  }
-
  enabledMonFeatures, err = getMonFeatures(intelRdtRoot)
  if err != nil {
  return
  }
+ if enabledMonFeatures.mbmTotalBytes || enabledMonFeatures.mbmLocalBytes {
+ mbmEnabled = true
+ }
+ if enabledMonFeatures.llcOccupancy {
+ cmtEnabled = true
+ }
  }
 }
 
@@ -313,6 +317,8 @@ type cpuInfoFlags struct {
  // Memory Bandwidth Monitoring related.
  MBMTotal bool
  MBMLocal bool
+
+ CMT bool // Cache Monitoring Technology
 }
 
 func parseCpuInfoFile(path string) (cpuInfoFlags, error) {
@@ -342,6 +348,8 @@ func parseCpuInfoFile(path string) (cpuInfoFlags, error) {
  infoFlags.MBMTotal = true
  case "cqm_mbm_local":
  infoFlags.MBMLocal = true
+ case "cqm_occup_llc":
+ infoFlags.CMT = true
  }
  }
  return infoFlags, nil
@@ -659,9 +667,11 @@ func (m *intelRdtManager) GetStats() (*Stats, error) {
  }
  }
 
- err = getMonitoringStats(containerPath, stats)
- if err != nil {
- return nil, err
+ if IsMBMEnabled() || IsCMTEnabled() {
+ err = getMonitoringStats(containerPath, stats)
+ if err != nil {
+ return nil, err
+ }
  }
 
  return stats, nil