config: Add Memory slots configuration.

Add configuration to decide the amount of slots that will be used in a VM

- This will limit the amount of times that memory can be hotplugged.
- Use memory slots provided by user.
- tests: aling struct

cli: kata-env: Add memory slots info.

- Show the slots to be added to the VM.

```diff
[Hypervisor]
  MachineType = "pc"
  Version = "QEMU ..."
  Path = "/opt/kata/bin/qemu-system-x86_64"
  BlockDeviceDriver = "virtio-scsi"
  Msize9p = 8192
+  MemorySlots = 10
  Debug = false
  UseVSock = false
```

Fixes: #751

Signed-off-by: Jose Carlos Venegas Munoz <jose.carlos.venegas.munoz@intel.com>

Makefile

@@ -125,6 +125,13 @@ DEFVCPUS := 1
 DEFMAXVCPUS := 0
 # Default memory size in MiB
 DEFMEMSZ := 2048
+# Default memory slots
+# Cases to consider :
+# - nvdimm rootfs image
+# - preallocated memory
+# - vm template memory
+# - hugepage memory
+DEFMEMSLOTS := 10
 #Default number of bridges
 DEFBRIDGES := 1
 #Default network model
@@ -202,6 +209,7 @@ USER_VARS += SYSCONFDIR
 USER_VARS += DEFVCPUS
 USER_VARS += DEFMAXVCPUS
 USER_VARS += DEFMEMSZ
+USER_VARS += DEFMEMSLOTS
 USER_VARS += DEFBRIDGES
 USER_VARS += DEFNETWORKMODEL
 USER_VARS += DEFDISABLEBLOCK
@@ -302,6 +310,7 @@ const defaultRootDirectory = "$(PKGRUNDIR)"
 const defaultVCPUCount uint32 = $(DEFVCPUS)
 const defaultMaxVCPUCount uint32 = $(DEFMAXVCPUS)
 const defaultMemSize uint32 = $(DEFMEMSZ) // MiB
+const defaultMemSlots uint32 = $(DEFMEMSLOTS)
 const defaultBridgesCount uint32 = $(DEFBRIDGES)
 const defaultInterNetworkingModel = "$(DEFNETWORKMODEL)"
 const defaultDisableBlockDeviceUse bool = $(DEFDISABLEBLOCK)
@@ -391,6 +400,7 @@ $(GENERATED_FILES): %: %.in Makefile VERSION
 		-e "s|@DEFVCPUS@|$(DEFVCPUS)|g" \
 		-e "s|@DEFMAXVCPUS@|$(DEFMAXVCPUS)|g" \
 		-e "s|@DEFMEMSZ@|$(DEFMEMSZ)|g" \
+		-e "s|@DEFMEMSLOTS@|$(DEFMEMSLOTS)|g" \
 		-e "s|@DEFBRIDGES@|$(DEFBRIDGES)|g" \
 		-e "s|@DEFNETWORKMODEL@|$(DEFNETWORKMODEL)|g" \
 		-e "s|@DEFDISABLEBLOCK@|$(DEFDISABLEBLOCK)|g" \

cli/config.go

@@ -84,6 +84,7 @@ type hypervisor struct {
 	NumVCPUs              int32  `toml:"default_vcpus"`
 	DefaultMaxVCPUs       uint32 `toml:"default_maxvcpus"`
 	MemorySize            uint32 `toml:"default_memory"`
+	MemSlots              uint32 `toml:"memory_slots"`
 	DefaultBridges        uint32 `toml:"default_bridges"`
 	Msize9p               uint32 `toml:"msize_9p"`
 	DisableBlockDeviceUse bool   `toml:"disable_block_device_use"`
@@ -247,6 +248,15 @@ func (h hypervisor) defaultMemSz() uint32 {
 	return h.MemorySize
 }
 
+func (h hypervisor) defaultMemSlots() uint32 {
+	slots := h.MemSlots
+	if slots == 0 {
+		slots = defaultMemSlots
+	}
+
+	return slots
+}
+
 func (h hypervisor) defaultBridges() uint32 {
 	if h.DefaultBridges == 0 {
 		return defaultBridgesCount
@@ -392,6 +402,7 @@ func newQemuHypervisorConfig(h hypervisor) (vc.HypervisorConfig, error) {
 		NumVCPUs:              h.defaultVCPUs(),
 		DefaultMaxVCPUs:       h.defaultMaxVCPUs(),
 		MemorySize:            h.defaultMemSz(),
+		MemSlots:              h.defaultMemSlots(),
 		DefaultBridges:        h.defaultBridges(),
 		DisableBlockDeviceUse: h.DisableBlockDeviceUse,
 		MemPrealloc:           h.MemPrealloc,

cli/config/configuration.toml.in

@@ -76,6 +76,11 @@ default_bridges = @DEFBRIDGES@
 # Default memory size in MiB for SB/VM.
 # If unspecified then it will be set @DEFMEMSZ@ MiB.
 #default_memory = @DEFMEMSZ@
+#
+# Default memory slots per SB/VM.
+# If unspecified then it will be set @DEFMEMSLOTS@.
+# This is will determine the times that memory will be hotadded to sandbox/VM.
+#memory_slots = @DEFMEMSLOTS@
 
 # Disable block device from being used for a container's rootfs.
 # In case of a storage driver like devicemapper where a container's 

cli/config_test.go

@@ -159,6 +159,7 @@ func createAllRuntimeConfigFiles(dir, hypervisor string) (config testRuntimeConf
 		EnableIOThreads:       enableIOThreads,
 		HotplugVFIOOnRootBus:  hotplugVFIOOnRootBus,
 		Msize9p:               defaultMsize9p,
+		MemSlots:              defaultMemSlots,
 	}
 
 	agentConfig := vc.KataAgentConfig{}

cli/kata-env.go

@@ -25,7 +25,7 @@ import (
 //
 // XXX: Increment for every change to the output format
 // (meaning any change to the EnvInfo type).
-const formatVersion = "1.0.16"
+const formatVersion = "1.0.17"
 
 // MetaInfo stores information on the format of the output itself
 type MetaInfo struct {
@@ -82,6 +82,7 @@ type HypervisorInfo struct {
 	Path              string
 	BlockDeviceDriver string
 	Msize9p           uint32
+	MemorySlots       uint32
 	Debug             bool
 	UseVSock          bool
 }
@@ -317,6 +318,7 @@ func getHypervisorInfo(config oci.RuntimeConfig) HypervisorInfo {
 		BlockDeviceDriver: config.HypervisorConfig.BlockDeviceDriver,
 		Msize9p:           config.HypervisorConfig.Msize9p,
 		UseVSock:          config.HypervisorConfig.UseVSock,
+		MemorySlots:       config.HypervisorConfig.MemSlots,
 	}
 }
 

cli/kata-env_test.go

@@ -262,6 +262,7 @@ func getExpectedHypervisor(config oci.RuntimeConfig) HypervisorInfo {
 		MachineType:       config.HypervisorConfig.HypervisorMachineType,
 		BlockDeviceDriver: config.HypervisorConfig.BlockDeviceDriver,
 		Msize9p:           config.HypervisorConfig.Msize9p,
+		MemorySlots:       config.HypervisorConfig.MemSlots,
 		Debug:             config.HypervisorConfig.Debug,
 	}
 }

virtcontainers/hypervisor.go

@@ -136,6 +136,25 @@ type Param struct {
 
 // HypervisorConfig is the hypervisor configuration.
 type HypervisorConfig struct {
+	// NumVCPUs specifies default number of vCPUs for the VM.
+	NumVCPUs uint32
+
+	//DefaultMaxVCPUs specifies the maximum number of vCPUs for the VM.
+	DefaultMaxVCPUs uint32
+
+	// DefaultMem specifies default memory size in MiB for the VM.
+	MemorySize uint32
+
+	// DefaultBridges specifies default number of bridges for the VM.
+	// Bridges can be used to hot plug devices
+	DefaultBridges uint32
+
+	// Msize9p is used as the msize for 9p shares
+	Msize9p uint32
+
+	// MemSlots specifies default memory slots the VM.
+	MemSlots uint32
+
 	// KernelParams are additional guest kernel parameters.
 	KernelParams []Param
 
@@ -169,25 +188,20 @@ type HypervisorConfig struct {
 	// emulated.
 	HypervisorMachineType string
 
+	// MemoryPath is the memory file path of VM memory. Used when either BootToBeTemplate or
+	// BootFromTemplate is true.
+	MemoryPath string
+
+	// DevicesStatePath is the VM device state file path. Used when either BootToBeTemplate or
+	// BootFromTemplate is true.
+	DevicesStatePath string
+
 	// customAssets is a map of assets.
 	// Each value in that map takes precedence over the configured assets.
 	// For example, if there is a value for the "kernel" key in this map,
 	// it will be used for the sandbox's kernel path instead of KernelPath.
 	customAssets map[assetType]*asset
 
-	// NumVCPUs specifies default number of vCPUs for the VM.
-	NumVCPUs uint32
-
-	//DefaultMaxVCPUs specifies the maximum number of vCPUs for the VM.
-	DefaultMaxVCPUs uint32
-
-	// DefaultMem specifies default memory size in MiB for the VM.
-	MemorySize uint32
-
-	// DefaultBridges specifies default number of bridges for the VM.
-	// Bridges can be used to hot plug devices
-	DefaultBridges uint32
-
 	// DisableBlockDeviceUse disallows a block device from being used.
 	DisableBlockDeviceUse bool
 
@@ -217,9 +231,6 @@ type HypervisorConfig struct {
 	// when running on top of another VMM.
 	DisableNestingChecks bool
 
-	// Msize9p is used as the msize for 9p shares
-	Msize9p uint32
-
 	// UseVSock use a vsock for agent communication
 	UseVSock bool
 
@@ -233,14 +244,6 @@ type HypervisorConfig struct {
 	// BootFromTemplate used to indicate if the VM should be created from a template VM
 	BootFromTemplate bool
 
-	// MemoryPath is the memory file path of VM memory. Used when either BootToBeTemplate or
-	// BootFromTemplate is true.
-	MemoryPath string
-
-	// DevicesStatePath is the VM device state file path. Used when either BootToBeTemplate or
-	// BootFromTemplate is true.
-	DevicesStatePath string
-
 	// DisableVhostNet is used to indicate if host supports vhost_net
 	DisableVhostNet bool
 }

virtcontainers/qemu.go

@@ -283,7 +283,7 @@ func (q *qemu) memoryTopology() (govmmQemu.Memory, error) {
 
 	memMb := uint64(q.config.MemorySize)
 
-	return q.arch.memoryTopology(memMb, hostMemMb), nil
+	return q.arch.memoryTopology(memMb, hostMemMb, uint8(q.config.MemSlots)), nil
 }
 
 func (q *qemu) qmpSocketPath(id string) (string, error) {
@@ -1236,7 +1236,7 @@ func genericBridges(number uint32, machineType string) []Bridge {
 	return bridges
 }
 
-func genericMemoryTopology(memoryMb, hostMemoryMb uint64) govmmQemu.Memory {
+func genericMemoryTopology(memoryMb, hostMemoryMb uint64, slots uint8) govmmQemu.Memory {
 	// NVDIMM device needs memory space 1024MB
 	// See https://github.com/clearcontainers/runtime/issues/380
 	memoryOffset := 1024
@@ -1248,7 +1248,7 @@ func genericMemoryTopology(memoryMb, hostMemoryMb uint64) govmmQemu.Memory {
 
 	memory := govmmQemu.Memory{
 		Size:   mem,
-		Slots:  defaultMemSlots,
+		Slots:  slots,
 		MaxMem: memMax,
 	}
 

virtcontainers/qemu_amd64.go

@@ -122,8 +122,8 @@ func (q *qemuAmd64) cpuModel() string {
 	return cpuModel
 }
 
-func (q *qemuAmd64) memoryTopology(memoryMb, hostMemoryMb uint64) govmmQemu.Memory {
-	return genericMemoryTopology(memoryMb, hostMemoryMb)
+func (q *qemuAmd64) memoryTopology(memoryMb, hostMemoryMb uint64, slots uint8) govmmQemu.Memory {
+	return genericMemoryTopology(memoryMb, hostMemoryMb, slots)
 }
 
 func (q *qemuAmd64) appendImage(devices []govmmQemu.Device, path string) ([]govmmQemu.Device, error) {

virtcontainers/qemu_amd64_test.go

@@ -86,13 +86,14 @@ func TestQemuAmd64MemoryTopology(t *testing.T) {
 
 	hostMem := uint64(100)
 	mem := uint64(120)
+	slots := uint8(10)
 	expectedMemory := govmmQemu.Memory{
 		Size:   fmt.Sprintf("%dM", mem),
-		Slots:  defaultMemSlots,
+		Slots:  slots,
 		MaxMem: fmt.Sprintf("%dM", hostMem+uint64(memoryOffset)),
 	}
 
-	m := amd64.memoryTopology(mem, hostMem)
+	m := amd64.memoryTopology(mem, hostMem, slots)
 	assert.Equal(expectedMemory, m)
 }
 

virtcontainers/qemu_arch_base.go

@@ -53,7 +53,7 @@ type qemuArch interface {
 	cpuModel() string
 
 	// memoryTopology returns the memory topology using the given amount of memoryMb and hostMemoryMb
-	memoryTopology(memoryMb, hostMemoryMb uint64) govmmQemu.Memory
+	memoryTopology(memoryMb, hostMemoryMb uint64, slots uint8) govmmQemu.Memory
 
 	// appendConsole appends a console to devices
 	appendConsole(devices []govmmQemu.Device, path string) []govmmQemu.Device
@@ -110,7 +110,6 @@ type qemuArchBase struct {
 const (
 	defaultCores     uint32 = 1
 	defaultThreads   uint32 = 1
-	defaultMemSlots  uint8  = 2
 	defaultCPUModel         = "host"
 	defaultBridgeBus        = "pcie.0"
 	maxDevIDSize            = 31
@@ -258,12 +257,12 @@ func (q *qemuArchBase) cpuModel() string {
 	return defaultCPUModel
 }
 
-func (q *qemuArchBase) memoryTopology(memoryMb, hostMemoryMb uint64) govmmQemu.Memory {
+func (q *qemuArchBase) memoryTopology(memoryMb, hostMemoryMb uint64, slots uint8) govmmQemu.Memory {
 	memMax := fmt.Sprintf("%dM", hostMemoryMb)
 	mem := fmt.Sprintf("%dM", memoryMb)
 	memory := govmmQemu.Memory{
 		Size:   mem,
-		Slots:  defaultMemSlots,
+		Slots:  slots,
 		MaxMem: memMax,
 	}
 

virtcontainers/qemu_arch_base_test.go

@@ -185,13 +185,14 @@ func TestQemuArchBaseMemoryTopology(t *testing.T) {
 
 	hostMem := uint64(100)
 	mem := uint64(120)
+	slots := uint8(12)
 	expectedMemory := govmmQemu.Memory{
 		Size:   fmt.Sprintf("%dM", mem),
-		Slots:  defaultMemSlots,
+		Slots:  slots,
 		MaxMem: fmt.Sprintf("%dM", hostMem),
 	}
 
-	m := qemuArchBase.memoryTopology(mem, hostMem)
+	m := qemuArchBase.memoryTopology(mem, hostMem, slots)
 	assert.Equal(expectedMemory, m)
 }
 

virtcontainers/qemu_ppc64le.go

@@ -109,7 +109,7 @@ func (q *qemuPPC64le) cpuModel() string {
 	return cpuModel
 }
 
-func (q *qemuPPC64le) memoryTopology(memoryMb, hostMemoryMb uint64) govmmQemu.Memory {
+func (q *qemuPPC64le) memoryTopology(memoryMb, hostMemoryMb uint64, slots uint8) govmmQemu.Memory {
 
 	if qemuMajorVersion >= 2 && qemuMinorVersion >= 10 {
 		q.Logger().Debug("Aligning maxmem to multiples of 256MB. Assumption: Kernel Version >= 4.11")
@@ -119,7 +119,7 @@ func (q *qemuPPC64le) memoryTopology(memoryMb, hostMemoryMb uint64) govmmQemu.Me
 		hostMemoryMb = defaultMemMaxPPC64le
 	}
 
-	return genericMemoryTopology(memoryMb, hostMemoryMb)
+	return genericMemoryTopology(memoryMb, hostMemoryMb, slots)
 }
 
 func (q *qemuPPC64le) appendImage(devices []govmmQemu.Device, path string) ([]govmmQemu.Device, error) {

virtcontainers/qemu_ppc64le_test.go

@@ -41,12 +41,13 @@ func TestQemuPPC64leMemoryTopology(t *testing.T) {
 
 	hostMem := uint64(1024)
 	mem := uint64(120)
+	slots := uint8(10)
 	expectedMemory := govmmQemu.Memory{
 		Size:   fmt.Sprintf("%dM", mem),
-		Slots:  defaultMemSlots,
+		Slots:  slots,
 		MaxMem: fmt.Sprintf("%dM", hostMem+uint64(memoryOffset)),
 	}
 
-	m := ppc64le.memoryTopology(mem, hostMem)
+	m := ppc64le.memoryTopology(mem, hostMem, slots)
 	assert.Equal(expectedMemory, m)
 }

virtcontainers/qemu_test.go

@@ -151,11 +151,13 @@ func TestQemuCPUTopology(t *testing.T) {
 
 func TestQemuMemoryTopology(t *testing.T) {
 	mem := uint32(1000)
+	slots := uint32(8)
 
 	q := &qemu{
 		arch: &qemuArchBase{},
 		config: HypervisorConfig{
 			MemorySize: mem,
+			MemSlots:   slots,
 		},
 	}
 
@@ -167,7 +169,7 @@ func TestQemuMemoryTopology(t *testing.T) {
 
 	expectedOut := govmmQemu.Memory{
 		Size:   fmt.Sprintf("%dM", mem),
-		Slots:  defaultMemSlots,
+		Slots:  uint8(slots),
 		MaxMem: memMax,
 	}
 

virtcontainers/sandbox.go

@@ -293,7 +293,8 @@ type Cmd struct {
 // Resources describes VM resources configuration.
 type Resources struct {
 	// Memory is the amount of available memory in MiB.
-	Memory uint
+	Memory      uint
+	MemorySlots uint8
 }
 
 // SandboxStatus describes a sandbox status.