using a struct for the spinlock and cleaned up the comments a little.

sync/spinlock.go

@@ -8,25 +8,28 @@ import (
 var state = [2]string{"Unlocked", "Locked"}
 
 // SpinLock implements a simple atomic spin lock, the zero value for a SpinLock is an unlocked spinlock.
-type SpinLock uint32
+type SpinLock struct {
+	l uint32
+}
 
-// Lock locks sl. If the lock is already in use, the calling goroutine blocks until the lock is freed.
+// Lock locks sl. If the lock is already in use, the caller blocks until Unlock is called
 func (sl *SpinLock) Lock() {
-	for !atomic.CompareAndSwapUint32((*uint32)(sl), 0, 1) {
+	for !atomic.CompareAndSwapUint32(&sl.l, 0, 1) {
 		runtime.Gosched() //allow other goroutines to do stuff.
 	}
 }
 
-// Unlock unlocks sl, unlike [Mutex.Unlock](http://golang.org/pkg/sync/#Mutex.Unlock), there's no harm calling it on an unlocked SpinLock.
+// Unlock unlocks sl, unlike [Mutex.Unlock](http://golang.org/pkg/sync/#Mutex.Unlock),
+// there's no harm calling it on an unlocked SpinLock
 func (sl *SpinLock) Unlock() {
-	atomic.StoreUint32((*uint32)(sl), 0)
+	atomic.StoreUint32(&sl.l, 0)
 }
 
 // TryLock will try to lock sl and return whether it succeed or not without blocking.
 func (sl *SpinLock) TryLock() bool {
-	return atomic.CompareAndSwapUint32((*uint32)(sl), 0, 1)
+	return atomic.CompareAndSwapUint32(&sl.l, 0, 1)
 }
 
 func (sl *SpinLock) String() string {
-	return state[*sl]
+	return state[sl.l]
 }