1// Copyright 2012 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package sync
6
7import "unsafe"
8
9// defined in package runtime
10
11// Semacquire waits until *s > 0 and then atomically decrements it.
12// It is intended as a simple sleep primitive for use by the synchronization
13// library and should not be used directly.
14func runtime_Semacquire(s *uint32)
15
16// SemacquireMutex is like Semacquire, but for profiling contended Mutexes.
17// If lifo is true, queue waiter at the head of wait queue.
18func runtime_SemacquireMutex(s *uint32, lifo bool)
19
20// Semrelease atomically increments *s and notifies a waiting goroutine
21// if one is blocked in Semacquire.
22// It is intended as a simple wakeup primitive for use by the synchronization
23// library and should not be used directly.
24// If handoff is true, pass count directly to the first waiter.
25func runtime_Semrelease(s *uint32, handoff bool)
26
27// Approximation of notifyList in runtime/sema.go. Size and alignment must
28// agree.
29type notifyList struct {
30	wait   uint32
31	notify uint32
32	lock   uintptr
33	head   unsafe.Pointer
34	tail   unsafe.Pointer
35}
36
37// See runtime/sema.go for documentation.
38func runtime_notifyListAdd(l *notifyList) uint32
39
40// See runtime/sema.go for documentation.
41func runtime_notifyListWait(l *notifyList, t uint32)
42
43// See runtime/sema.go for documentation.
44func runtime_notifyListNotifyAll(l *notifyList)
45
46// See runtime/sema.go for documentation.
47func runtime_notifyListNotifyOne(l *notifyList)
48
49// Ensure that sync and runtime agree on size of notifyList.
50func runtime_notifyListCheck(size uintptr)
51func init() {
52	var n notifyList
53	runtime_notifyListCheck(unsafe.Sizeof(n))
54}
55
56// Active spinning runtime support.
57// runtime_canSpin reports whether spinning makes sense at the moment.
58func runtime_canSpin(i int) bool
59
60// runtime_doSpin does active spinning.
61func runtime_doSpin()
62
63func runtime_nanotime() int64
64