我的所有线程都卡在一个点上，此时的跟踪如下：
(gdb) info threads
9 Thread 0x7fa872994700 (LWP 10301) 0x000000327b60e264 in __lll_lock_wait () from /lib64/libpthread.so.0
8 Thread 0x7fa87379c700 (LWP 10302) 0x000000327b2accdd in nanosleep () from /lib64/libc.so.6
7 Thread 0x7fa871b7c700 (LWP 10303) 0x000000327b2db74d in read () from /lib64/libc.so.6
6 Thread 0x7fa87117b700 (LWP 10306) 0x000000327b60e264 in __lll_lock_wait () from /lib64/libpthread.so.0
5 Thread 0x7fa864e14700 (LWP 10307) 0x000000327b60e264 in __lll_lock_wait () from /lib64/libpthread.so.0
4 Thread 0x7fa85ffff700 (LWP 10308) 0x000000327b2db7ad in write () from /lib64/libc.so.6
3 Thread 0x7fa85f5fe700 (LWP 10309) 0x000000327b60e264 in __lll_lock_wait () from …