diff --git a/cpu/cpu.go b/cpu/cpu.go
index 049869e2..ceaf77fe 100644
--- a/cpu/cpu.go
+++ b/cpu/cpu.go
@@ -54,10 +54,9 @@ type lastPercent struct {
 }
 
 var lastCPUPercent lastPercent
-var invoke common.Invoker
+var invoke common.Invoker = common.Invoke{}
 
 func init() {
-	invoke = common.Invoke{}
 	lastCPUPercent.Lock()
 	lastCPUPercent.lastCPUTimes, _ = Times(false)
 	lastCPUPercent.lastPerCPUTimes, _ = Times(true)
diff --git a/disk/disk.go b/disk/disk.go
index a2c47204..1c31047d 100644
--- a/disk/disk.go
+++ b/disk/disk.go
@@ -6,11 +6,7 @@ import (
 	"github.com/shirou/gopsutil/internal/common"
 )
 
-var invoke common.Invoker
-
-func init() {
-	invoke = common.Invoke{}
-}
+var invoke common.Invoker = common.Invoke{}
 
 type UsageStat struct {
 	Path              string  `json:"path"`
diff --git a/docker/docker.go b/docker/docker.go
index 83716fdc..76791c2a 100644
--- a/docker/docker.go
+++ b/docker/docker.go
@@ -10,11 +10,7 @@ import (
 var ErrDockerNotAvailable = errors.New("docker not available")
 var ErrCgroupNotAvailable = errors.New("cgroup not available")
 
-var invoke common.Invoker
-
-func init() {
-	invoke = common.Invoke{}
-}
+var invoke common.Invoker = common.Invoke{}
 
 type CgroupMemStat struct {
 	ContainerID             string `json:"containerID"`
diff --git a/host/host.go b/host/host.go
index a256a6c8..1e9e9bb6 100644
--- a/host/host.go
+++ b/host/host.go
@@ -6,11 +6,7 @@ import (
 	"github.com/shirou/gopsutil/internal/common"
 )
 
-var invoke common.Invoker
-
-func init() {
-	invoke = common.Invoke{}
-}
+var invoke common.Invoker = common.Invoke{}
 
 // A HostInfoStat describes the host status.
 // This is not in the psutil but it useful.
diff --git a/load/load.go b/load/load.go
index dfe32a1e..90858895 100644
--- a/load/load.go
+++ b/load/load.go
@@ -6,11 +6,7 @@ import (
 	"github.com/shirou/gopsutil/internal/common"
 )
 
-var invoke common.Invoker
-
-func init() {
-	invoke = common.Invoke{}
-}
+var invoke common.Invoker = common.Invoke{}
 
 type AvgStat struct {
 	Load1  float64 `json:"load1"`
diff --git a/mem/mem.go b/mem/mem.go
index 87dfb53b..bdf15ba5 100644
--- a/mem/mem.go
+++ b/mem/mem.go
@@ -6,11 +6,7 @@ import (
 	"github.com/shirou/gopsutil/internal/common"
 )
 
-var invoke common.Invoker
-
-func init() {
-	invoke = common.Invoke{}
-}
+var invoke common.Invoker = common.Invoke{}
 
 // Memory usage statistics. Total, Available and Used contain numbers of bytes
 // for human consumption.
diff --git a/net/net.go b/net/net.go
index 428e68e1..c31f5124 100644
--- a/net/net.go
+++ b/net/net.go
@@ -12,11 +12,7 @@ import (
 	"github.com/shirou/gopsutil/internal/common"
 )
 
-var invoke common.Invoker
-
-func init() {
-	invoke = common.Invoke{}
-}
+var invoke common.Invoker = common.Invoke{}
 
 type IOCountersStat struct {
 	Name        string `json:"name"`        // interface name
diff --git a/process/process.go b/process/process.go
index e20742a5..29d114ea 100644
--- a/process/process.go
+++ b/process/process.go
@@ -11,11 +11,7 @@ import (
 	"github.com/shirou/gopsutil/mem"
 )
 
-var invoke common.Invoker
-
-func init() {
-	invoke = common.Invoke{}
-}
+var invoke common.Invoker = common.Invoke{}
 
 type Process struct {
 	Pid            int32 `json:"pid"`