qemu: add appendMemoryKnobs helper

To fix travis failure about cyclomatic complexity in appendKnobs().

Signed-off-by: Peng Tao <bergwolf@gmail.com>

qemu/qemu.go

@@ -1468,23 +1468,7 @@ func (config *Config) appendKernel() {
 	}
 }
 
-func (config *Config) appendKnobs() {
+func (config *Config) appendMemoryKnobs() {
-	if config.Knobs.NoUserConfig == true {
-		config.qemuParams = append(config.qemuParams, "-no-user-config")
-	}
-
-	if config.Knobs.NoDefaults == true {
-		config.qemuParams = append(config.qemuParams, "-nodefaults")
-	}
-
-	if config.Knobs.NoGraphic == true {
-		config.qemuParams = append(config.qemuParams, "-nographic")
-	}
-
-	if config.Knobs.Daemonize == true {
-		config.qemuParams = append(config.qemuParams, "-daemonize")
-	}
-
 	if config.Knobs.HugePages == true {
 		if config.Memory.Size != "" {
 			dimmName := "dimm1"
@@ -1525,6 +1509,26 @@ func (config *Config) appendKnobs() {
 			config.qemuParams = append(config.qemuParams, numaMemParam)
 		}
 	}
+}
+
+func (config *Config) appendKnobs() {
+	if config.Knobs.NoUserConfig == true {
+		config.qemuParams = append(config.qemuParams, "-no-user-config")
+	}
+
+	if config.Knobs.NoDefaults == true {
+		config.qemuParams = append(config.qemuParams, "-nodefaults")
+	}
+
+	if config.Knobs.NoGraphic == true {
+		config.qemuParams = append(config.qemuParams, "-nographic")
+	}
+
+	if config.Knobs.Daemonize == true {
+		config.qemuParams = append(config.qemuParams, "-daemonize")
+	}
+
+	config.appendMemoryKnobs()
 
 	if config.Knobs.Realtime == true {
 		config.qemuParams = append(config.qemuParams, "-realtime")

qemu/qemu_test.go

@@ -28,7 +28,12 @@ const volumeUUID = "67d86208-b46c-4465-9018-e14187d4010"
 
 func testAppend(structure interface{}, expected string, t *testing.T) {
 	var config Config
+	testConfigAppend(&config, structure, expected, t)
 
+	return
+}
+
+func testConfigAppend(config *Config, structure interface{}, expected string, t *testing.T) {
 	switch s := structure.(type) {
 	case Machine:
 		config.Machine = s
@@ -425,6 +430,97 @@ func TestAppendKnobsAllFalse(t *testing.T) {
 	testAppend(knobs, knobsString, t)
 }
 
+func TestAppendMemoryHugePages(t *testing.T) {
+	conf := &Config{
+		Memory: Memory{
+			Size:   "1G",
+			Slots:  8,
+			MaxMem: "3G",
+			Path:   "foobar",
+		},
+	}
+	memString := "-m 1G,slots=8,maxmem=3G"
+	testConfigAppend(conf, conf.Memory, memString, t)
+
+	knobs := Knobs{
+		HugePages:           true,
+		MemPrealloc:         true,
+		FileBackedMem:       true,
+		FileBackedMemShared: true,
+	}
+	knobsString := "-object memory-backend-file,id=dimm1,size=1G,mem-path=/dev/hugepages,share=on,prealloc=on -numa node,memdev=dimm1"
+	mlockFalseString := "-realtime mlock=off"
+
+	testConfigAppend(conf, knobs, memString+" "+knobsString+" "+mlockFalseString, t)
+}
+
+func TestAppendMemoryMemPrealloc(t *testing.T) {
+	conf := &Config{
+		Memory: Memory{
+			Size:   "1G",
+			Slots:  8,
+			MaxMem: "3G",
+			Path:   "foobar",
+		},
+	}
+	memString := "-m 1G,slots=8,maxmem=3G"
+	testConfigAppend(conf, conf.Memory, memString, t)
+
+	knobs := Knobs{
+		MemPrealloc:         true,
+		FileBackedMem:       true,
+		FileBackedMemShared: true,
+	}
+	knobsString := "-object memory-backend-ram,id=dimm1,size=1G,prealloc=on -device pc-dimm,id=dimm1,memdev=dimm1"
+	mlockFalseString := "-realtime mlock=off"
+
+	testConfigAppend(conf, knobs, memString+" "+knobsString+" "+mlockFalseString, t)
+}
+
+func TestAppendMemoryFileBackedMemShared(t *testing.T) {
+	conf := &Config{
+		Memory: Memory{
+			Size:   "1G",
+			Slots:  8,
+			MaxMem: "3G",
+			Path:   "foobar",
+		},
+	}
+	memString := "-m 1G,slots=8,maxmem=3G"
+	testConfigAppend(conf, conf.Memory, memString, t)
+
+	knobs := Knobs{
+		FileBackedMem:       true,
+		FileBackedMemShared: true,
+	}
+	knobsString := "-object memory-backend-file,id=dimm1,size=1G,mem-path=foobar,share=on -numa node,memdev=dimm1"
+	mlockFalseString := "-realtime mlock=off"
+
+	testConfigAppend(conf, knobs, memString+" "+knobsString+" "+mlockFalseString, t)
+}
+
+func TestAppendMemoryFileBackedMem(t *testing.T) {
+	conf := &Config{
+		Memory: Memory{
+			Size:   "1G",
+			Slots:  8,
+			MaxMem: "3G",
+			Path:   "foobar",
+		},
+	}
+	memString := "-m 1G,slots=8,maxmem=3G"
+	testConfigAppend(conf, conf.Memory, memString, t)
+
+	knobs := Knobs{
+		FileBackedMem:       true,
+		FileBackedMemShared: false,
+	}
+	knobsString := "-object memory-backend-file,id=dimm1,size=1G,mem-path=foobar -numa node,memdev=dimm1"
+	mlockFalseString := "-realtime mlock=off"
+
+	testConfigAppend(conf, knobs, memString+" "+knobsString+" "+mlockFalseString, t)
+}
+
 var kernelString = "-kernel /opt/vmlinux.container -initrd /opt/initrd.container -append root=/dev/pmem0p1 rootflags=dax,data=ordered,errors=remount-ro rw rootfstype=ext4 tsc=reliable"
 
 func TestAppendKernel(t *testing.T) {