清华大学操作系统课程实验 作业.zip

#include <proc.h> #include <kmalloc.h> #include <string.h> #include <sync.h> #include <pmm.h> #include <error.h> #include <sched.h> #include <elf.h> #include <vmm.h> #include <trap.h> #include <stdio.h> #include <stdlib.h> #include <assert.h> #include <unistd.h> #include <fs.h> #include <vfs.h> #include <sysfile.h> /* ------------- process/thread mechanism design&implementation ------------- (an simplified Linux process/thread mechanism ) introduction: ucore implements a simple process/thread mechanism. process contains the independent memory sapce, at least one threads for execution, the kernel data(for management), processor state (for context switch), files(in lab6), etc. ucore needs to manage all these details efficiently. In ucore, a thread is just a special kind of process(share process's memory). ------------------------------ process state : meaning -- reason PROC_UNINIT : uninitialized -- alloc_proc PROC_SLEEPING : sleeping -- try_free_pages, do_wait, do_sleep PROC_RUNNABLE : runnable(maybe running) -- proc_init, wakeup_proc, PROC_ZOMBIE : almost dead -- do_exit ----------------------------- process state changing: alloc_proc RUNNING + +--<----<--+ + + proc_run + V +-->---->--+ PROC_UNINIT -- proc_init/wakeup_proc --> PROC_RUNNABLE -- try_free_pages/do_wait/do_sleep --> PROC_SLEEPING -- A + + | +--- do_exit --> PROC_ZOMBIE + + + -----------------------wakeup_proc---------------------------------- ----------------------------- process relations parent: proc->parent (proc is children) children: proc->cptr (proc is parent) older sibling: proc->optr (proc is younger sibling) younger sibling: proc->yptr (proc is older sibling) ----------------------------- related syscall for process: SYS_exit : process exit, -->do_exit SYS_fork : create child process, dup mm -->do_fork-->wakeup_proc SYS_wait : wait process -->do_wait SYS_exec : after fork, process execute a program -->load a program and refresh the mm SYS_clone : create child thread -->do_fork-->wakeup_proc SYS_yield : process flag itself need resecheduling, -- proc->need_sched=1, then scheduler will rescheule this process SYS_sleep : process sleep -->do_sleep SYS_kill : kill process -->do_kill-->proc->flags |= PF_EXITING -->wakeup_proc-->do_wait-->do_exit SYS_getpid : get the process's pid */ // the process set's list list_entry_t proc_list; #define HASH_SHIFT 10 #define HASH_LIST_SIZE (1 << HASH_SHIFT) #define pid_hashfn(x) (hash32(x, HASH_SHIFT)) // has list for process set based on pid static list_entry_t hash_list[HASH_LIST_SIZE]; // idle proc struct proc_struct *idleproc = NULL; // init proc struct proc_struct *initproc = NULL; // current proc struct proc_struct *current = NULL; static int nr_process = 0; void kernel_thread_entry(void); void forkrets(struct trapframe *tf); // 调用 trap/trapentry.S 中的 forkrets: void switch_to(struct context *from, struct context *to); // 调用switch.S // alloc_proc - alloc a proc_struct and init all fields of proc_struct static struct proc_struct * alloc_proc(void) { struct proc_struct *proc = kmalloc(sizeof(struct proc_struct)); if (proc != NULL) { //LAB4:EXERCISE1 YOUR CODE /* * below fields in proc_struct need to be initialized * enum proc_state state; // Process state * int pid; // Process ID * int runs; // the running times of Proces * uintptr_t kstack; // Process kernel stack * volatile bool need_resched; // bool value: need to be rescheduled to release CPU? * struct proc_struct *parent; // the parent process * struct mm_struct *mm; // Process's memory management field * struct context context; // Switch here to run process * struct trapframe *tf; // Trap frame for current interrupt * uintptr_t cr3; // CR3 register: the base addr of Page Directroy Table(PDT) * uint32_t flags; // Process flag * char name[PROC_NAME_LEN + 1]; // Process name */ //LAB5 YOUR CODE : (update LAB4 steps) /* * below fields(add in LAB5) in proc_struct need to be initialized * uint32_t wait_state; // waiting state * struct proc_struct *cptr, *yptr, *optr; // relations between processes */ //LAB6 YOUR CODE : (update LAB5 steps) /* * below fields（以下字段）(add in LAB6) in proc_struct need to be initialized（初始化） * 当然，这些字段都在 proc.h 头文件中的 proc_struct 结构体中定义过了。 * struct run_queue *rq; // running queue contains Process（运行队列） * list_entry_t run_link; // the entry linked in run queue（运行队列指针） * int time_slice; // time slice for occupying the CPU（时间片） * skew_heap_entry_t lab6_run_pool; // FOR LAB6 ONLY: the entry in the run pool * uint32_t lab6_stride; // FOR LAB6 ONLY: the current stride of the process * uint32_t lab6_priority; // FOR LAB6 ONLY: the priority of process, set by lab6_set_priority(uint32_t) */ //LAB8:EXERCISE2 YOUR CODE HINT:need add some code to init fs in proc_struct, ... /* * 执行的是第一步初始化工作 */ proc->state = PROC_UNINIT; // 设置了进程的状态为“初始”态，这表示进程已经 “出生”了，正在获取资源茁壮成长中； proc->pid = -1; // 未分配的进程pid是-1 先设置pid为无效值-1，用户调完alloc_proc函数后再根据实际情况设置pid。 // 设置了进程的pid为-1，这表示进程的“身份证号”还没有办好； proc->cr3 = boot_cr3; // boot_cr3指向了uCore启动时建立好的内核虚拟空间的页目录表首地址 // 表明由于该内核线程在内核中运行，故采用为uCore内核已经建立的页表，即设置为在uCore内核页表的起始地址boot_cr3。 proc->runs = 0; proc->kstack = 0; // 记录了分配给该进程/线程的内核栈的位置 proc->need_resched = 0; // 是否需要调度 proc->parent = NULL; // 父进程 proc->mm = 0; // 虚拟内存结构体（lab4实验可忽略） /* * void *memset(void *s, int c, unsigned long n) * 函数解释：将s中当前位置后面的n个字节 （typedef unsigned int size_t ）用 ch 替换并返回 s * 该函数用于清空一个结构体中所有的成员变量，下面解释三个参数： * 第一个参数：位置指针，例如数组名、结构体首地址 * 第二个参数：替换为什么 * memset 函数的第�