github.com/fenixara/go@v0.0.0-20170127160404-96ea0918e670/src/sync/runtime.go (about)

     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  
     5  package sync
     6  
     7  import "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.
    14  func runtime_Semacquire(s *uint32)
    15  
    16  // SemacquireMutex is like Semacquire, but for profiling contended Mutexes.
    17  func runtime_SemacquireMutex(*uint32)
    18  
    19  // Semrelease atomically increments *s and notifies a waiting goroutine
    20  // if one is blocked in Semacquire.
    21  // It is intended as a simple wakeup primitive for use by the synchronization
    22  // library and should not be used directly.
    23  func runtime_Semrelease(s *uint32)
    24  
    25  // Approximation of notifyList in runtime/sema.go. Size and alignment must
    26  // agree.
    27  type notifyList struct {
    28  	wait   uint32
    29  	notify uint32
    30  	lock   uintptr
    31  	head   unsafe.Pointer
    32  	tail   unsafe.Pointer
    33  }
    34  
    35  // See runtime/sema.go for documentation.
    36  func runtime_notifyListAdd(l *notifyList) uint32
    37  
    38  // See runtime/sema.go for documentation.
    39  func runtime_notifyListWait(l *notifyList, t uint32)
    40  
    41  // See runtime/sema.go for documentation.
    42  func runtime_notifyListNotifyAll(l *notifyList)
    43  
    44  // See runtime/sema.go for documentation.
    45  func runtime_notifyListNotifyOne(l *notifyList)
    46  
    47  // Ensure that sync and runtime agree on size of notifyList.
    48  func runtime_notifyListCheck(size uintptr)
    49  func init() {
    50  	var n notifyList
    51  	runtime_notifyListCheck(unsafe.Sizeof(n))
    52  }
    53  
    54  // Active spinning runtime support.
    55  // runtime_canSpin returns true is spinning makes sense at the moment.
    56  func runtime_canSpin(i int) bool
    57  
    58  // runtime_doSpin does active spinning.
    59  func runtime_doSpin()