Do not set -1 for swappiness

Do not set a default value for swappiness as the default value should be
`nil`

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

daemon/daemon.go

@@ -1243,3 +1243,11 @@ func (daemon *Daemon) checkpointAndSave(container *container.Container) error {
 	}
 	return nil
 }
+
+// because the CLI sends a -1 when it wants to unset the swappiness value
+// we need to clear it on the server side
+func fixMemorySwappiness(resources *containertypes.Resources) {
+	if resources.MemorySwappiness != nil && *resources.MemorySwappiness == -1 {
+		resources.MemorySwappiness = nil
+	}
+}

daemon/daemon_solaris.go

@@ -143,6 +143,7 @@ func UsingSystemd(config *Config) bool {
 // verifyPlatformContainerSettings performs platform-specific validation of the
 // hostconfig and config structures.
 func verifyPlatformContainerSettings(daemon *Daemon, hostConfig *containertypes.HostConfig, config *containertypes.Config, update bool) ([]string, error) {
+	fixMemorySwappiness(resources)
 	warnings := []string{}
 	sysInfo := sysinfo.New(true)
 	// NOTE: We do not enforce a minimum value for swap limits for zones on Solaris and
@@ -163,7 +164,7 @@ func verifyPlatformContainerSettings(daemon *Daemon, hostConfig *containertypes.
 	}
 	// Solaris NOTE: We allow and encourage setting the swap without setting the memory limit.
 
-	if hostConfig.MemorySwappiness != nil && *hostConfig.MemorySwappiness != -1 && !sysInfo.MemorySwappiness {
+	if hostConfig.MemorySwappiness != nil && !sysInfo.MemorySwappiness {
 		warnings = append(warnings, "Your kernel does not support memory swappiness capabilities, memory swappiness discarded.")
 		logrus.Warnf("Your kernel does not support memory swappiness capabilities, memory swappiness discarded.")
 		hostConfig.MemorySwappiness = nil

daemon/daemon_unix.go

@@ -282,10 +282,6 @@ func (daemon *Daemon) adaptContainerSettings(hostConfig *containertypes.HostConf
 		return err
 	}
 	hostConfig.SecurityOpt = append(hostConfig.SecurityOpt, opts...)
-	if hostConfig.MemorySwappiness == nil {
-		defaultSwappiness := int64(-1)
-		hostConfig.MemorySwappiness = &defaultSwappiness
-	}
 	if hostConfig.OomKillDisable == nil {
 		defaultOomKillDisable := false
 		hostConfig.OomKillDisable = &defaultOomKillDisable
@@ -296,6 +292,7 @@ func (daemon *Daemon) adaptContainerSettings(hostConfig *containertypes.HostConf
 
 func verifyContainerResources(resources *containertypes.Resources, sysInfo *sysinfo.SysInfo, update bool) ([]string, error) {
 	warnings := []string{}
+	fixMemorySwappiness(resources)
 
 	// memory subsystem checks and adjustments
 	if resources.Memory != 0 && resources.Memory < linuxMinMemory {
@@ -318,14 +315,14 @@ func verifyContainerResources(resources *containertypes.Resources, sysInfo *sysi
 	if resources.Memory == 0 && resources.MemorySwap > 0 && !update {
 		return warnings, fmt.Errorf("You should always set the Memory limit when using Memoryswap limit, see usage")
 	}
-	if resources.MemorySwappiness != nil && *resources.MemorySwappiness != -1 && !sysInfo.MemorySwappiness {
+	if resources.MemorySwappiness != nil && !sysInfo.MemorySwappiness {
 		warnings = append(warnings, "Your kernel does not support memory swappiness capabilities or the cgroup is not mounted. Memory swappiness discarded.")
 		logrus.Warn("Your kernel does not support memory swappiness capabilities, or the cgroup is not mounted. Memory swappiness discarded.")
 		resources.MemorySwappiness = nil
 	}
 	if resources.MemorySwappiness != nil {
 		swappiness := *resources.MemorySwappiness
-		if swappiness < -1 || swappiness > 100 {
+		if swappiness < 0 || swappiness > 100 {
 			return warnings, fmt.Errorf("Invalid value: %v, valid memory swappiness range is 0-100", swappiness)
 		}
 	}

daemon/daemon_windows.go

@@ -100,7 +100,7 @@ func (daemon *Daemon) adaptContainerSettings(hostConfig *containertypes.HostConf
 
 func verifyContainerResources(resources *containertypes.Resources, isHyperv bool) ([]string, error) {
 	warnings := []string{}
-
+	fixMemorySwappiness(resources)
 	if !isHyperv {
 		// The processor resource controls are mutually exclusive on
 		// Windows Server Containers, the order of precedence is
@@ -197,7 +197,7 @@ func verifyContainerResources(resources *containertypes.Resources, isHyperv bool
 	if resources.MemorySwap != 0 {
 		return warnings, fmt.Errorf("invalid option: Windows does not support MemorySwap")
 	}
-	if resources.MemorySwappiness != nil && *resources.MemorySwappiness != -1 {
+	if resources.MemorySwappiness != nil {
 		return warnings, fmt.Errorf("invalid option: Windows does not support MemorySwappiness")
 	}
 	if resources.OomKillDisable != nil && *resources.OomKillDisable {

integration-cli/docker_api_containers_test.go

@@ -1448,7 +1448,7 @@ func (s *DockerSuite) TestPostContainersCreateMemorySwappinessHostConfigOmitted(
 	var containerJSON types.ContainerJSON
 	c.Assert(json.Unmarshal(body, &containerJSON), check.IsNil)
 
-	c.Assert(*containerJSON.HostConfig.MemorySwappiness, check.Equals, int64(-1))
+	c.Assert(containerJSON.HostConfig.MemorySwappiness, check.IsNil)
 }
 
 // check validation is done daemon side and not only in cli