feat: add cpu max burst support

Signed-off-by: Lucas Jacques <contact@lucasjacques.com>

Author: lucas-jacques

cgroup2/cpu.go

@@ -32,11 +32,16 @@ func NewCPUMax(quota *int64, period *uint64) CPUMax {
 	return CPUMax(strings.Join([]string{max, strconv.FormatUint(*period, 10)}, " "))
 }
 
+func NewCPUMaxBurst(burst uint64) string {
+	return strconv.FormatUint(burst, 10)
+}
+
 type CPU struct {
-	Weight *uint64
-	Max    CPUMax
-	Cpus   string
-	Mems   string
+	Weight   *uint64
+	Max      CPUMax
+	MaxBurst string
+	Cpus     string
+	Mems     string
 }
 
 func (c CPUMax) extractQuotaAndPeriod() (int64, uint64) {
@@ -79,5 +84,12 @@ func (r *CPU) Values() (o []Value) {
 			value:    r.Mems,
 		})
 	}
+	if r.MaxBurst != "" {
+		o = append(o, Value{
+			filename: "cpu.max.burst",
+			value:    r.MaxBurst,
+		})
+	}
+
 	return o
 }

cgroup2/cpuv2_test.go

@@ -32,17 +32,19 @@ func TestCgroupv2CpuStats(t *testing.T) {
 	group := "/cpu-test-cg"
 	groupPath := fmt.Sprintf("%s-%d", group, os.Getpid())
 	var (
+		burst  uint64 = 1000
 		quota  int64  = 10000
 		period uint64 = 8000
 		weight uint64 = 100
 	)
 
 	c, err := NewManager(defaultCgroup2Path, groupPath, &Resources{
 		CPU: &CPU{
-			Weight: &weight,
-			Max:    NewCPUMax(&quota, &period),
-			Cpus:   "0",
-			Mems:   "0",
+			Weight:   &weight,
+			Max:      NewCPUMax(&quota, &period),
+			Cpus:     "0",
+			Mems:     "0",
+			MaxBurst: NewCPUMaxBurst(burst),
 		},
 	})
 	require.NoError(t, err, "failed to init new cgroup manager")
@@ -54,6 +56,7 @@ func TestCgroupv2CpuStats(t *testing.T) {
 	checkFileContent(t, c.path, "cpu.max", "10000 8000")
 	checkFileContent(t, c.path, "cpuset.cpus", "0")
 	checkFileContent(t, c.path, "cpuset.mems", "0")
+	checkFileContent(t, c.path, "cpu.max.burst", strconv.FormatUint(burst, 10))
 }
 
 func TestSystemdCgroupCpuController(t *testing.T) {

cgroup2/utils.go

@@ -172,6 +172,9 @@ func ToResources(spec *specs.LinuxResources) *Resources {
 		if period := cpu.Period; period != nil {
 			resources.CPU.Max = NewCPUMax(cpu.Quota, period)
 		}
+		if burst := cpu.Burst; burst != nil {
+			resources.CPU.MaxBurst = NewCPUMaxBurst(*burst)
+		}
 	}
 	if mem := spec.Memory; mem != nil {
 		resources.Memory = &Memory{}