static tid_t allocate_tid (void);
/* Initializes the threading system by transforming the code
- that's currently running into a thread. Note that this is
- possible only because the loader was careful to put the bottom
- of the stack at a page boundary; it won't work in general.
- Also initializes the run queue.
+ that's currently running into a thread. This can't work in
+ general and it is possible in this case only because loader.S
+ was careful to put the bottom of the stack at a page boundary.
+
+ Also initializes the run queue and the tid lock.
After calling this function, be sure to initialize the page
allocator before trying to create any threads with
| |
| |
+---------------------------------+
- | magic |
- | : |
- | : |
- | name |
- | status |
+ | magic |
+ | : |
+ | : |
+ | name |
+ | status |
0 kB +---------------------------------+
The upshot of this is twofold:
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()
+ dynamic allocation with malloc() or palloc_get_page()
instead.
The first symptom of either of these problems will probably be
uint32_t *pagedir; /* Page directory. */
#endif
- /* Owned by thread.c */
+ /* Owned by thread.c. */
unsigned magic; /* Detects stack overflow. */
};
struct thread *thread_current (void);
tid_t thread_tid (void);
const char *thread_name (void);
+
void thread_exit (void) NO_RETURN;
void thread_yield (void);
void thread_block (void);