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互斥锁和死锁

#!/usr/bin/env python
# encoding: utf-8  
# Date: 2018/6/18

# # 死锁
# from threading import Thread,Lock
# import time
# mutexA = Lock()
# mutexB = Lock()
#
#
# class MyThread(Thread):
#     def run(self):
#         self.f1()
#         self.f2()
#
#     def f1(self):
#         mutexA.acquire()
#         print('%s 拿到了A锁' % self.name)
#         mutexB.acquire()
#         print('%s 拿到了B锁' % self.name)
#         mutexB.release()
#
#         mutexA.release()
#
#     def f2(self):
#         mutexB.acquire()
#         print('%s 拿到了B锁' % self.name)
#         time.sleep(0.1)
#
#         mutexA.acquire()
#         print('%s 拿到了A锁' % self.name)
#         mutexA.release()
#
#         mutexB.release()
#
#
# if __name__ == '__main__':
#     for i in range(10):
#         t = MyThread()
#         t.start()

# 互斥锁只能acquire一次
# from threading import Thread,Lock
#
# mutexA = Lock()
#
# mutexA.acquire()
# mutexA.release()

# 递归锁:可以连续acquire多次,每一次acuqire一次计数器加1,只有计数为0时,才能被抢到
from threading import Thread,RLock
import time

mutexB = mutexA = RLock()


class MyThread(Thread):
    def run(self):
            self.f1()
            self.f2()

    def f1(self):
        mutexA.acquire()
        print('%s 拿到了A锁' % self.name)
        mutexB.acquire()
        print('%s 拿到了B锁' % self.name)
        mutexB.release()

        mutexA.release()

    def f2(self):
        mutexB.acquire()
        print('%s 拿到了B锁' % self.name)
        time.sleep(0.1)

        mutexA.acquire()
        print('%s 拿到了A锁' % self.name)
        mutexA.release()

        mutexB.release()


if __name__ == '__main__':
    for i in range(10):
        t = MyThread()
        t.start()

posted on 2018-06-18 23:06  风-fmgao  阅读(131)  评论(0编辑  收藏  举报