diff options
Diffstat (limited to 'src/pkg/sync/mutex.go')
| -rw-r--r-- | src/pkg/sync/mutex.go | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/src/pkg/sync/mutex.go b/src/pkg/sync/mutex.go index 23691aa33..309970f1e 100644 --- a/src/pkg/sync/mutex.go +++ b/src/pkg/sync/mutex.go @@ -8,23 +8,24 @@ // is better done via channels and communication. package sync -func cas(val *int32, old, new int32) bool -func semacquire(*int32) -func semrelease(*int32) +import "runtime" + +func cas(val *uint32, old, new uint32) bool // A Mutex is a mutual exclusion lock. // Mutexes can be created as part of other structures; // the zero value for a Mutex is an unlocked mutex. type Mutex struct { - key int32; - sema int32; + key uint32; + sema uint32; } -func xadd(val *int32, delta int32) (new int32) { +func xadd(val *uint32, delta int32) (new uint32) { for { v := *val; - if cas(val, v, v+delta) { - return v+delta; + nv := v+uint32(delta); + if cas(val, v, nv) { + return nv; } } panic("unreached"); @@ -38,7 +39,7 @@ func (m *Mutex) Lock() { // changed from 0 to 1; we hold lock return; } - semacquire(&m.sema); + runtime.Semacquire(&m.sema); } // Unlock unlocks m. @@ -52,7 +53,7 @@ func (m *Mutex) Unlock() { // changed from 1 to 0; no contention return; } - semrelease(&m.sema); + runtime.Semrelease(&m.sema); } // Stub implementation of r/w locks. |