Imported Upstream version 4.8.1

[platform/upstream/gcc48.git] / libgo / go / sync / mutex.go

diff --git a/libgo/go/sync/mutex.go b/libgo/go/sync/mutex.go
index 9494cc3..b4629eb 100644 (file)
--- a/libgo/go/sync/mutex.go
+++ b/libgo/go/sync/mutex.go
@@ -10,7 +10,10 @@
 // Values containing the types defined in this package should not be copied.
 package sync
 
-import "sync/atomic"
+import (
+       "sync/atomic"
+       "unsafe"
+)
 
 // A Mutex is a mutual exclusion lock.
 // Mutexes can be created as part of other structures;
@@ -38,6 +41,9 @@ const (
 func (m *Mutex) Lock() {
        // Fast path: grab unlocked mutex.
        if atomic.CompareAndSwapInt32(&m.state, 0, mutexLocked) {
+               if raceenabled {
+                       raceAcquire(unsafe.Pointer(m))
+               }
                return
        }
 
@@ -61,6 +67,10 @@ func (m *Mutex) Lock() {
                        awoke = true
                }
        }
+
+       if raceenabled {
+               raceAcquire(unsafe.Pointer(m))
+       }
 }
 
 // Unlock unlocks m.
@@ -70,6 +80,10 @@ func (m *Mutex) Lock() {
 // It is allowed for one goroutine to lock a Mutex and then
 // arrange for another goroutine to unlock it.
 func (m *Mutex) Unlock() {
+       if raceenabled {
+               raceRelease(unsafe.Pointer(m))
+       }
+
        // Fast path: drop lock bit.
        new := atomic.AddInt32(&m.state, -mutexLocked)
        if (new+mutexLocked)&mutexLocked == 0 {