Merge pull request #14 from alitto/bug/fix-waiting-count

Prevent WaitingTasks counter to wrap around and upgrade to Go v1.16

.travis.yml

@@ -11,6 +11,7 @@ go:
   - 1.13.x
   - 1.14.x
   - 1.15.x
+  - 1.16.x
 
 # Enable Go Modules
 env:

examples/dynamic_size/go.mod

@@ -1,9 +1,9 @@
 module github.com/alitto/pond/examples/dynamic_size
 
-go 1.15
+go 1.16
 
 require (
-	github.com/alitto/pond v1.5.0
+	github.com/alitto/pond v1.5.1
 )
 
 replace github.com/alitto/pond => ../../

examples/fixed_size/go.mod

@@ -1,9 +1,9 @@
 module github.com/alitto/pond/examples/fixed_size
 
-go 1.15
+go 1.16
 
 require (
-	github.com/alitto/pond v1.5.0
+	github.com/alitto/pond v1.5.1
 )
 
 replace github.com/alitto/pond => ../../

examples/prometheus/go.mod

@@ -1,9 +1,9 @@
 module github.com/alitto/pond/examples/fixed_size
 
-go 1.15
+go 1.16
 
 require (
-	github.com/alitto/pond v1.5.0
+	github.com/alitto/pond v1.5.1
 	github.com/prometheus/client_golang v1.9.0
 )
 

examples/task_group/go.mod

@@ -1,9 +1,9 @@
 module github.com/alitto/pond/examples/task_group
 
-go 1.15
+go 1.16
 
 require (
-	github.com/alitto/pond v1.5.0
+	github.com/alitto/pond v1.5.1
 )
 
 replace github.com/alitto/pond => ../../

go.mod

@@ -1,3 +1,3 @@
 module github.com/alitto/pond
 
-go 1.15
+go 1.16

pond.go

@@ -211,13 +211,15 @@ func (p *WorkerPool) submit(task func(), canWaitForIdleWorker bool) (submitted b
 		return false
 	}
 
-	defer func() {
-		if submitted {
-			// Increment submitted task count
-			atomic.AddUint64(&p.submittedTaskCount, 1)
+	// Increment submitted and waiting task counters as soon as we receive a task
+	atomic.AddUint64(&p.submittedTaskCount, 1)
+	atomic.AddUint64(&p.waitingTaskCount, 1)
 
-			// Increment waiting task count
-			atomic.AddUint64(&p.waitingTaskCount, 1)
+	defer func() {
+		if !submitted {
+			// Task was not sumitted to the pool, decrement submitted and waiting task counters
+			atomic.AddUint64(&p.submittedTaskCount, ^uint64(0))
+			atomic.AddUint64(&p.waitingTaskCount, ^uint64(0))
 		}
 	}()