diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/internal/synctest/synctest_test.go | 26 | ||||
| -rw-r--r-- | src/runtime/synctest.go | 7 |
2 files changed, 33 insertions, 0 deletions
diff --git a/src/internal/synctest/synctest_test.go b/src/internal/synctest/synctest_test.go index 7d1e04e2ba..450d5f5416 100644 --- a/src/internal/synctest/synctest_test.go +++ b/src/internal/synctest/synctest_test.go @@ -433,6 +433,32 @@ func TestWaitGroup(t *testing.T) { }) } +func TestHappensBefore(t *testing.T) { + var v int + synctest.Run(func() { + go func() { + v++ // 1 + }() + // Wait creates a happens-before relationship on the above goroutine exiting. + synctest.Wait() + go func() { + v++ // 2 + }() + }) + // Run exiting creates a happens-before relationship on goroutines started in the bubble. + synctest.Run(func() { + v++ // 3 + // There is a happens-before relationship between the time.AfterFunc call, + // and the func running. + time.AfterFunc(0, func() { + v++ // 4 + }) + }) + if got, want := v, 4; got != want { + t.Errorf("v = %v, want %v", got, want) + } +} + func wantPanic(t *testing.T, want string) { if e := recover(); e != nil { if got := fmt.Sprint(e); got != want { diff --git a/src/runtime/synctest.go b/src/runtime/synctest.go index 498c3b92dd..65bb15dfbb 100644 --- a/src/runtime/synctest.go +++ b/src/runtime/synctest.go @@ -182,6 +182,8 @@ func synctestRun(f func()) { sg.active++ for { if raceenabled { + // Establish a happens-before relationship between a timer being created, + // and the timer running. raceacquireg(gp, gp.syncGroup.raceaddr()) } unlock(&sg.mu) @@ -205,6 +207,11 @@ func synctestRun(f func()) { total := sg.total unlock(&sg.mu) + if raceenabled { + // Establish a happens-before relationship between bubbled goroutines exiting + // and Run returning. + raceacquireg(gp, gp.syncGroup.raceaddr()) + } if total != 1 { panic("deadlock: all goroutines in bubble are blocked") } |