diff --git a/common/common.go b/common/common.go
index 99119ff61df534b6d1d0785b6a57b495919a378c..28936240bde6ed9b0273d8593aeaa0d223e5458a 100644
--- a/common/common.go
+++ b/common/common.go
@@ -94,7 +94,7 @@ func mustParseFloat64(val string) float64 {
 }
 
 // Check the target string slice containes src or not
-func stringContains(target []string, src string) bool {
+func StringContains(target []string, src string) bool {
 	for _, t := range target {
 		if t == src {
 			return true
@@ -126,7 +126,7 @@ func attributes(m interface{}) map[string]reflect.Type {
 	return attrs
 }
 
-func pathExists(filename string) bool {
+func PathExists(filename string) bool {
 	if _, err := os.Stat(filename); err == nil {
 		return true
 	}
diff --git a/docker/docker_linux.go b/docker/docker_linux.go
index 0845837ef6404e4190f46952126245f6e956bb57..c7a10a80228a9ccec088ecfd9149b098f9c08fb1 100644
--- a/docker/docker_linux.go
+++ b/docker/docker_linux.go
@@ -10,6 +10,7 @@ import (
 	"strings"
 
 	common "github.com/shirou/gopsutil/common"
+	cpu "github.com/shirou/gopsutil/cpu"
 )
 
 type CgroupMemStat struct {
@@ -64,7 +65,7 @@ func GetDockerIDList() ([]string, error) {
 // containerid is same as docker id if you use docker.
 // If you use container via systemd.slice, you could use
 // containerid = docker-<container id>.scope and base=/sys/fs/cgroup/cpuacct/system.slice/
-func CgroupCPU(containerid string, base string) (*CPUTimesStat, error) {
+func CgroupCPU(containerid string, base string) (*cpu.CPUTimesStat, error) {
 	if len(base) == 0 {
 		base = "/sys/fs/cgroup/cpuacct/docker"
 	}
@@ -75,7 +76,7 @@ func CgroupCPU(containerid string, base string) (*CPUTimesStat, error) {
 	if len(containerid) == 0 {
 		containerid = "all"
 	}
-	ret := &CPUTimesStat{CPU: containerid}
+	ret := &cpu.CPUTimesStat{CPU: containerid}
 	for _, line := range lines {
 		fields := strings.Split(line, " ")
 		if fields[0] == "user" {
@@ -95,7 +96,7 @@ func CgroupCPU(containerid string, base string) (*CPUTimesStat, error) {
 	return ret, nil
 }
 
-func CgroupCPUDocker(containerid string) (*CPUTimesStat, error) {
+func CgroupCPUDocker(containerid string) (*cpu.CPUTimesStat, error) {
 	return CgroupCPU(containerid, "/sys/fs/cgroup/cpuacct/docker")
 }
 
diff --git a/host/host_linux.go b/host/host_linux.go
index 46480055fe01f9e17b610c3003740619882937bb..ebd0c0ca2d9c8f810cb674f051b7575ebce72c46 100644
--- a/host/host_linux.go
+++ b/host/host_linux.go
@@ -105,7 +105,7 @@ func Users() ([]UserStat, error) {
 
 func getLSB() (*LSB, error) {
 	ret := &LSB{}
-	if pathExists("/etc/lsb-release") {
+	if common.PathExists("/etc/lsb-release") {
 		contents, err := common.ReadLines("/etc/lsb-release")
 		if err != nil {
 			return ret, err // return empty
@@ -126,7 +126,7 @@ func getLSB() (*LSB, error) {
 				ret.Description = field[1]
 			}
 		}
-	} else if pathExists("/usr/bin/lsb_release") {
+	} else if common.PathExists("/usr/bin/lsb_release") {
 		out, err := exec.Command("/usr/bin/lsb_release").Output()
 		if err != nil {
 			return ret, err
@@ -160,19 +160,19 @@ func GetPlatformInformation() (platform string, family string, version string, e
 		lsb = &LSB{}
 	}
 
-	if pathExists("/etc/oracle-release") {
+	if common.PathExists("/etc/oracle-release") {
 		platform = "oracle"
 		contents, err := common.ReadLines("/etc/oracle-release")
 		if err == nil {
 			version = getRedhatishVersion(contents)
 		}
-	} else if pathExists("/etc/enterprise-release") {
+	} else if common.PathExists("/etc/enterprise-release") {
 		platform = "oracle"
 		contents, err := common.ReadLines("/etc/enterprise-release")
 		if err == nil {
 			version = getRedhatishVersion(contents)
 		}
-	} else if pathExists("/etc/debian_version") {
+	} else if common.PathExists("/etc/debian_version") {
 		if lsb.ID == "Ubuntu" {
 			platform = "ubuntu"
 			version = lsb.Release
@@ -180,7 +180,7 @@ func GetPlatformInformation() (platform string, family string, version string, e
 			platform = "linuxmint"
 			version = lsb.Release
 		} else {
-			if pathExists("/usr/bin/raspi-config") {
+			if common.PathExists("/usr/bin/raspi-config") {
 				platform = "raspbian"
 			} else {
 				platform = "debian"
@@ -190,19 +190,19 @@ func GetPlatformInformation() (platform string, family string, version string, e
 				version = contents[0]
 			}
 		}
-	} else if pathExists("/etc/redhat-release") {
+	} else if common.PathExists("/etc/redhat-release") {
 		contents, err := common.ReadLines("/etc/redhat-release")
 		if err == nil {
 			version = getRedhatishVersion(contents)
 			platform = getRedhatishPlatform(contents)
 		}
-	} else if pathExists("/etc/system-release") {
+	} else if common.PathExists("/etc/system-release") {
 		contents, err := common.ReadLines("/etc/system-release")
 		if err == nil {
 			version = getRedhatishVersion(contents)
 			platform = getRedhatishPlatform(contents)
 		}
-	} else if pathExists("/etc/gentoo-release") {
+	} else if common.PathExists("/etc/gentoo-release") {
 		platform = "gentoo"
 		contents, err := common.ReadLines("/etc/gentoo-release")
 		if err == nil {
@@ -210,7 +210,7 @@ func GetPlatformInformation() (platform string, family string, version string, e
 		}
 		// TODO: suse detection
 		// TODO: slackware detecion
-	} else if pathExists("/etc/arch-release") {
+	} else if common.PathExists("/etc/arch-release") {
 		platform = "arch"
 		// TODO: exherbo detection
 	} else if lsb.ID == "RedHat" {
@@ -280,78 +280,78 @@ func GetVirtualization() (string, string, error) {
 	var system string
 	var role string
 
-	if pathExists("/proc/xen") {
+	if common.PathExists("/proc/xen") {
 		system = "xen"
 		role = "guest" // assume guest
 
-		if pathExists("/proc/xen/capabilities") {
+		if common.PathExists("/proc/xen/capabilities") {
 			contents, err := common.ReadLines("/proc/xen/capabilities")
 			if err == nil {
-				if stringContains(contents, "control_d") {
+				if common.StringContains(contents, "control_d") {
 					role = "host"
 				}
 			}
 		}
 	}
-	if pathExists("/proc/modules") {
+	if common.PathExists("/proc/modules") {
 		contents, err := common.ReadLines("/proc/modules")
 		if err == nil {
-			if stringContains(contents, "kvm") {
+			if common.StringContains(contents, "kvm") {
 				system = "kvm"
 				role = "host"
-			} else if stringContains(contents, "vboxdrv") {
+			} else if common.StringContains(contents, "vboxdrv") {
 				system = "vbox"
 				role = "host"
-			} else if stringContains(contents, "vboxguest") {
+			} else if common.StringContains(contents, "vboxguest") {
 				system = "vbox"
 				role = "guest"
 			}
 		}
 	}
 
-	if pathExists("/proc/cpuinfo") {
+	if common.PathExists("/proc/cpuinfo") {
 		contents, err := common.ReadLines("/proc/cpuinfo")
 		if err == nil {
-			if stringContains(contents, "QEMU Virtual CPU") ||
-				stringContains(contents, "Common KVM processor") ||
-				stringContains(contents, "Common 32-bit KVM processor") {
+			if common.StringContains(contents, "QEMU Virtual CPU") ||
+				common.StringContains(contents, "Common KVM processor") ||
+				common.StringContains(contents, "Common 32-bit KVM processor") {
 				system = "kvm"
 				role = "guest"
 			}
 		}
 	}
 
-	if pathExists("/proc/bc/0") {
+	if common.PathExists("/proc/bc/0") {
 		system = "openvz"
 		role = "host"
-	} else if pathExists("/proc/vz") {
+	} else if common.PathExists("/proc/vz") {
 		system = "openvz"
 		role = "guest"
 	}
 
 	// not use dmidecode because it requires root
 
-	if pathExists("/proc/self/status") {
+	if common.PathExists("/proc/self/status") {
 		contents, err := common.ReadLines("/proc/self/status")
 		if err == nil {
 
-			if stringContains(contents, "s_context:") ||
-				stringContains(contents, "VxID:") {
+			if common.StringContains(contents, "s_context:") ||
+				common.StringContains(contents, "VxID:") {
 				system = "linux-vserver"
 			}
 			// TODO: guest or host
 		}
 	}
 
-	if pathExists("/proc/self/cgroup") {
+	if common.PathExists("/proc/self/cgroup") {
 		contents, err := common.ReadLines("/proc/self/cgroup")
 		if err == nil {
 
-			if stringContains(contents, "lxc") ||
-				stringContains(contents, "docker") {
+			if common.StringContains(contents, "lxc") ||
+				common.StringContains(contents, "docker") {
 				system = "lxc"
 				role = "guest"
-			} else if pathExists("/usr/bin/lxc-version") { // TODO: which
+			} else if common.PathExists("/usr/bin/lxc-version") { // TODO: which
 				system = "lxc"
 				role = "host"
 			}
diff --git a/process/process_linux.go b/process/process_linux.go
index ede8f3fb126d1c975cd639810667f3a0047ddebd..e4bd597bee7c81f90cacb7944a570be2815ef810 100644
--- a/process/process_linux.go
+++ b/process/process_linux.go
@@ -13,6 +13,7 @@ import (
 
 	common "github.com/shirou/gopsutil/common"
 	cpu "github.com/shirou/gopsutil/cpu"
+	host "github.com/shirou/gopsutil/host"
 	net "github.com/shirou/gopsutil/net"
 )
 
@@ -555,7 +556,7 @@ func (p *Process) fillFromStat() (string, int32, *cpu.CPUTimesStat, int64, int32
 		System: float32(stime * (1000 / ClockTicks)),
 	}
 
-	bootTime, _ := BootTime()
+	bootTime, _ := host.BootTime()
 	t, err := strconv.ParseUint(fields[21], 10, 64)
 	if err != nil {
 		return "", 0, nil, 0, 0, err