thread.h

https://github.com/wookayin/pintos/blob/master/src/threads/thread.h

 

ifndef THREADS_THREAD_H
	THREADS_THREAD_H
	>
	>
	>
	ifdef VM
	endif
	*/
	enum thread_status
	{
	*/
	*/
	*/
	*/
	};
	/* Thread identifier type.
	*/
	tid_t;
	*/
	*/
	*/
	*/
	*/
	/* A kernel thread or user process.
	Each thread structure is stored in its own 4 kB page. The
	thread structure itself sits at the very bottom of the page
	(at offset 0). The rest of the page is reserved for the
	thread's kernel stack, which grows downward from the top of
	the page (at offset 4 kB). Here's an illustration:
	4 kB +---------------------------------+
	| kernel stack |
	| | |
	| | |
	| V |
	| grows downward |
	| |
	| |
	| |
	| |
	| |
	| |
	| |
	| |
	+---------------------------------+
	| magic |
	| : |
	| : |
	| name |
	| status |
	0 kB +---------------------------------+
	The upshot of this is twofold:
	1. First, `struct thread' must not be allowed to grow too
	big. If it does, then there will not be enough room for
	the kernel stack. Our base `struct thread' is only a
	few bytes in size. It probably should stay well under 1
	kB.
	2. Second, kernel stacks must not be allowed to grow too
	large. If a stack overflows, it will corrupt the thread
	state. Thus, kernel functions should not allocate large
	structures or arrays as non-static local variables. Use
	dynamic allocation with malloc() or palloc_get_page()
	instead.
	The first symptom of either of these problems will probably be
	an assertion failure in thread_current(), which checks that
	the `magic' member of the running thread's `struct thread' is
	set to THREAD_MAGIC. Stack overflow will normally change this
	*/
	/* The `elem' member has a dual purpose. It can be an element in
	the run queue (thread.c), or it can be an element in a
	semaphore wait list (synch.c). It can be used these two ways
	only because they are mutually exclusive: only a thread in the
	ready state is on the run queue, whereas only a thread in the
	*/
	struct thread
	{
	*/
	*/
	*/
	*/
	*/
	*/
	*/
	*/
	*/
	*/
	*/
	*/
	// needed for priority donations
	*/
	*/
	ifdef USERPROG
	*/
	*/
	// Project 2: file descriptors and process table
	*/
	*/
	/* List of children processes of this thread,
	*/
	*/
	*/
	/* The current value of the user program’s stack pointer.
	A page fault might occur in the kernel, so we might
	*/
	endif
	ifdef VM
	// Project 3: Supplemental page table.
	*/
	// Project 3: Memory Mapped Files.
	*/
	endif
	// Project 4: CWD.
	struct dir *cwd;
	*/
	*/
	};
	/* If false (default), use round-robin scheduler.
	If true, use multi-level feedback queue scheduler.
	*/
	bool thread_mlfqs;
	void);
	void);
	int64_t tick);
	void);
	void *aux);
	void *);
	void);
	struct thread *);
	int64_t wake_tick);
	void);
	void);
	void);
	void) NO_RETURN;
	void);
	*/
	void *aux);
	void *);
	void);
	int);
	int priority);
	void);
	int);
	void);
	void);
	*/