// Copyright 2013 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. //go:build plan9 package runtime import "runtime/internal/atomic" var netpollInited atomic.Uint32 var netpollStubLock mutex var netpollNote note // netpollBroken, protected by netpollBrokenLock, avoids a double notewakeup. var netpollBrokenLock mutex var netpollBroken bool func netpollGenericInit() { netpollInited.Store(1) } func netpollBreak() { lock(&netpollBrokenLock) broken := netpollBroken netpollBroken = true if !broken { notewakeup(&netpollNote) } unlock(&netpollBrokenLock) } // Polls for ready network connections. // Returns list of goroutines that become runnable. func netpoll(delay int64) (gList, int32) { // Implementation for platforms that do not support // integrated network poller. if delay != 0 { // This lock ensures that only one goroutine tries to use // the note. It should normally be completely uncontended. lock(&netpollStubLock) lock(&netpollBrokenLock) noteclear(&netpollNote) netpollBroken = false unlock(&netpollBrokenLock) notetsleep(&netpollNote, delay) unlock(&netpollStubLock) // Guard against starvation in case the lock is contended // (eg when running TestNetpollBreak). osyield() } return gList{}, 0 } func netpollinited() bool { return netpollInited.Load() != 0 } func netpollAnyWaiters() bool { return false } func netpollAdjustWaiters(delta int32) { }