Merge pull request #5511 from greatroar/atomic

ui/progress: Restore atomics in Counter

internal/ui/progress/counter.go

@@ -1,7 +1,7 @@
 package progress
 
 import (
-	"sync"
+	"sync/atomic"
 	"time"
 )
 
@@ -17,17 +17,13 @@ type Func func(value uint64, total uint64, runtime time.Duration, final bool)
 // The Func is also called when SIGUSR1 (or SIGINFO, on BSD) is received.
 type Counter struct {
 	Updater
-
-	valueMutex sync.Mutex
-	value      uint64
-	max        uint64
+	value, max atomic.Uint64
 }
 
 // NewCounter starts a new Counter.
 func NewCounter(interval time.Duration, total uint64, report Func) *Counter {
-	c := &Counter{
-		max: total,
-	}
+	c := new(Counter)
+	c.max.Store(total)
 	c.Updater = *NewUpdater(interval, func(runtime time.Duration, final bool) {
 		v, maxV := c.Get()
 		report(v, maxV, runtime, final)
@@ -37,33 +33,22 @@ func NewCounter(interval time.Duration, total uint64, report Func) *Counter {
 
 // Add v to the Counter. This method is concurrency-safe.
 func (c *Counter) Add(v uint64) {
-	if c == nil {
-		return
+	if c != nil {
+		c.value.Add(v)
 	}
-
-	c.valueMutex.Lock()
-	c.value += v
-	c.valueMutex.Unlock()
 }
 
 // SetMax sets the maximum expected counter value. This method is concurrency-safe.
 func (c *Counter) SetMax(max uint64) {
-	if c == nil {
-		return
+	if c != nil {
+		c.max.Store(max)
 	}
-	c.valueMutex.Lock()
-	c.max = max
-	c.valueMutex.Unlock()
 }
 
 // Get returns the current value and the maximum of c.
 // This method is concurrency-safe.
 func (c *Counter) Get() (v, max uint64) {
-	c.valueMutex.Lock()
-	v, max = c.value, c.max
-	c.valueMutex.Unlock()
-
-	return v, max
+	return c.value.Load(), c.max.Load()
 }
 
 func (c *Counter) Done() {

internal/ui/progress/updater.go

@@ -57,17 +57,13 @@ func (c *Updater) Done() {
 
 func (c *Updater) run() {
 	defer close(c.stopped)
-	defer func() {
-		// Must be a func so that time.Since isn't called at defer time.
-		c.report(time.Since(c.start), true)
-	}()
 
 	var tick <-chan time.Time
 	if c.tick != nil {
 		tick = c.tick.C
 	}
 	signalsCh := signals.GetProgressChannel()
-	for {
+	for final := false; !final; {
 		var now time.Time
 
 		select {
@@ -76,9 +72,9 @@ func (c *Updater) run() {
 			debug.Log("Signal received: %v\n", sig)
 			now = time.Now()
 		case <-c.stop:
-			return
+			final, now = true, time.Now()
 		}
 
-		c.report(now.Sub(c.start), false)
+		c.report(now.Sub(c.start), final)
 	}
 }

internal/ui/progress/updater_test.go

@@ -9,13 +9,17 @@ import (
 )
 
 func TestUpdater(t *testing.T) {
-	finalSeen := false
-	var ncalls int
+	var (
+		finalSeen = false
+		ncalls    = 0
+		dur       time.Duration
+	)
 
 	report := func(d time.Duration, final bool) {
 		if final {
 			finalSeen = true
 		}
+		dur = d
 		ncalls++
 	}
 	c := progress.NewUpdater(10*time.Millisecond, report)
@@ -24,6 +28,7 @@ func TestUpdater(t *testing.T) {
 
 	test.Assert(t, finalSeen, "final call did not happen")
 	test.Assert(t, ncalls > 0, "no progress was reported")
+	test.Assert(t, dur > 0, "duration must be positive")
 }
 
 func TestUpdaterStopTwice(_ *testing.T) {