cli/command/container: calculateCPUPercentUnix: simplify

Pass the whole CPUStats struct instead of deconstructing it to separate
variables.

Signed-off-by: Sebastiaan van Stijn <[email protected]>

Author: thaJeztah

cli/command/container/stats_helpers.go

@@ -49,13 +49,8 @@ func (s *stats) isKnownContainer(cid string) (int, bool) {
 	return -1, false
 }
 
-func collect(ctx context.Context, s *Stats, cli client.ContainerAPIClient, streamStats bool, waitFirst *sync.WaitGroup) { //nolint:gocyclo
-	var (
-		getFirst       bool
-		previousCPU    uint64
-		previousSystem uint64
-		u              = make(chan error, 1)
-	)
+func collect(ctx context.Context, s *Stats, cli client.ContainerAPIClient, streamStats bool, waitFirst *sync.WaitGroup) {
+	var getFirst bool
 
 	defer func() {
 		// if error happens and we get nothing of stats, release wait group whatever
@@ -71,6 +66,7 @@ func collect(ctx context.Context, s *Stats, cli client.ContainerAPIClient, strea
 		return
 	}
 
+	u := make(chan error, 1)
 	go func() {
 		defer response.Body.Close()
 		dec := json.NewDecoder(response.Body)
@@ -97,9 +93,7 @@ func collect(ctx context.Context, s *Stats, cli client.ContainerAPIClient, strea
 			}
 
 			if daemonOSType != "windows" {
-				previousCPU = v.PreCPUStats.CPUUsage.TotalUsage
-				previousSystem = v.PreCPUStats.SystemUsage
-				cpuPercent = calculateCPUPercentUnix(previousCPU, previousSystem, v)
+				cpuPercent = calculateCPUPercentUnix(v.PreCPUStats, v.CPUStats)
 				blkRead, blkWrite = calculateBlockIO(v.BlkioStats)
 				mem = calculateMemUsageUnixNoCache(v.MemoryStats)
 				memLimit = float64(v.MemoryStats.Limit)
@@ -165,18 +159,18 @@ func collect(ctx context.Context, s *Stats, cli client.ContainerAPIClient, strea
 	}
 }
 
-func calculateCPUPercentUnix(previousCPU, previousSystem uint64, v *container.StatsResponse) float64 {
+func calculateCPUPercentUnix(previousCPU container.CPUStats, curCPUStats container.CPUStats) float64 {
 	var (
 		cpuPercent = 0.0
 		// calculate the change for the cpu usage of the container in between readings
-		cpuDelta = float64(v.CPUStats.CPUUsage.TotalUsage) - float64(previousCPU)
+		cpuDelta = float64(curCPUStats.CPUUsage.TotalUsage) - float64(previousCPU.CPUUsage.TotalUsage)
 		// calculate the change for the entire system between readings
-		systemDelta = float64(v.CPUStats.SystemUsage) - float64(previousSystem)
-		onlineCPUs  = float64(v.CPUStats.OnlineCPUs)
+		systemDelta = float64(curCPUStats.SystemUsage) - float64(previousCPU.SystemUsage)
+		onlineCPUs  = float64(curCPUStats.OnlineCPUs)
 	)
 
 	if onlineCPUs == 0.0 {
-		onlineCPUs = float64(len(v.CPUStats.CPUUsage.PercpuUsage))
+		onlineCPUs = float64(len(curCPUStats.CPUUsage.PercpuUsage))
 	}
 	if systemDelta > 0.0 && cpuDelta > 0.0 {
 		cpuPercent = (cpuDelta / systemDelta) * onlineCPUs * 100.0