Go语学习笔记 - 互斥锁 | 从零开始Go语言

学习笔记，写到哪是哪。

同一时刻只有一个协程可以访问该资源，其他线程只能等待，互斥性。互斥锁在工作项目中用的还是比较多的，但是要注意死锁，也就是一定要注意释放锁的过程是否能够执行。

样例代码如下

package main
import (
  "fmt"
  "sync"
  "time"
)
var (
  count  int
  myLock sync.Mutex
  wg1    sync.WaitGroup
)
func GetCount() int {
  myLock.Lock()
  fmt.Println("GetCount lock ")
  defer myLock.Unlock()
  defer fmt.Println("GetCount unlock ")
  return count
}
func IncCount() {
  myLock.Lock()
  fmt.Println("IncCount lock ")
  defer myLock.Unlock()
  defer fmt.Println("IncCount unlock ")
  count += 1
}
func main() {
  wg1.Add(2)
  go func() {
  defer wg1.Done()
  for i := 0; i < 11; i++ {
    fmt.Println("count -> ", GetCount())
    time.Sleep(1 * time.Second)
  }
  }()
  go func() {
  defer wg1.Done()
  for i := 0; i < 10; i++ {
    IncCount()
    fmt.Println("count -> add 1")
    time.Sleep(1 * time.Second)
  }
  }()
  wg1.Wait()
}

执行结果

IncCount lock

IncCount unlock

count -> add 1

GetCount lock

GetCount unlock

count ->  1

GetCount lock

GetCount unlock

count ->  1

IncCount lock

IncCount unlock

count -> add 1

IncCount lock

IncCount unlock

count -> add 1

GetCount lock

GetCount unlock

count ->  3

GetCount lock

GetCount unlock

count ->  3

IncCount lock

IncCount unlock

count -> add 1

IncCount lock

IncCount unlock

count -> add 1

GetCount lock

GetCount unlock

count ->  5

GetCount lock

GetCount unlock

count ->  5

IncCount lock

IncCount unlock

count -> add 1

IncCount lock

IncCount unlock

count -> add 1

GetCount lock

GetCount unlock

count ->  7

GetCount lock

GetCount unlock

count ->  7

IncCount lock

IncCount unlock

count -> add 1

IncCount lock

IncCount unlock

count -> add 1

GetCount lock

GetCount unlock

count ->  9

GetCount lock

GetCount unlock

count ->  9

IncCount lock

IncCount unlock

count -> add 1

GetCount lock

GetCount unlock

count ->  10

Process finished with the exit code 0

注意

1、可以看到两个方法在争抢锁，一旦占用，必须要等到释放才可以使用。

2、这里使用了sync.WaitGroup来对协程进行等待。