diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/pkg/sync/waitgroup.go | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/src/pkg/sync/waitgroup.go b/src/pkg/sync/waitgroup.go index 2a0a94f40..22681115c 100644 --- a/src/pkg/sync/waitgroup.go +++ b/src/pkg/sync/waitgroup.go @@ -95,13 +95,6 @@ func (wg *WaitGroup) Wait() { } wg.m.Lock() w := atomic.AddInt32(&wg.waiters, 1) - if raceenabled && w == 1 { - // Wait's must be synchronized with the first Add. - // Need to model this is as a write to race with the read in Add. - // As the consequence, can do the write only for the first waiter, - // otherwise concurrent Wait's will race with each other. - raceWrite(unsafe.Pointer(&wg.sema)) - } // This code is racing with the unlocked path in Add above. // The code above modifies counter and then reads waiters. // We must modify waiters and then read counter (the opposite order) @@ -119,6 +112,13 @@ func (wg *WaitGroup) Wait() { } return } + if raceenabled && w == 1 { + // Wait must be synchronized with the first Add. + // Need to model this is as a write to race with the read in Add. + // As a consequence, can do the write only for the first waiter, + // otherwise concurrent Waits will race with each other. + raceWrite(unsafe.Pointer(&wg.sema)) + } if wg.sema == nil { wg.sema = new(uint32) } |