1.Lab-3 page tables

Lab: page tables

1.Speed up system calls (easy)

1. 加速getpid()系统调用速度

2. 映射一页在USYSCALL位置，向其中写入一个结构体

   struct usyscall {
     int pid;  // Process ID
   };
   

3. 赋予用户态只读权限

代码：github

Which other xv6 system call(s) could be made faster using this shared page? Explain how.

2.Print a page table (easy)

代码：github

3.Detect which pages have been accessed (hard)

代码：github