diff options
Diffstat (limited to 'extras/mini-os/sched.c')
| -rw-r--r-- | extras/mini-os/sched.c | 198 |
1 files changed, 62 insertions, 136 deletions
diff --git a/extras/mini-os/sched.c b/extras/mini-os/sched.c index ee1adb6549..9b111c28e5 100644 --- a/extras/mini-os/sched.c +++ b/extras/mini-os/sched.c @@ -5,7 +5,7 @@ * * File: sched.c * Author: Grzegorz Milos - * Changes: + * Changes: Robert Kaiser * * Date: Aug 2005 * @@ -54,82 +54,9 @@ #define DEBUG(_f, _a...) ((void)0) #endif - -#define RUNNABLE_FLAG 0x00000001 - -#define is_runnable(_thread) (_thread->flags & RUNNABLE_FLAG) -#define set_runnable(_thread) (_thread->flags |= RUNNABLE_FLAG) -#define clear_runnable(_thread) (_thread->flags &= ~RUNNABLE_FLAG) - - struct thread *idle_thread = NULL; LIST_HEAD(exited_threads); -void idle_thread_fn(void *unused); - -void dump_stack(struct thread *thread) -{ - unsigned long *bottom = (unsigned long *)(thread->stack + 2*4*1024); - unsigned long *pointer = (unsigned long *)thread->sp; - int count; - if(thread == current) - { -#ifdef __i386__ - asm("movl %%esp,%0" - : "=r"(pointer)); -#else - asm("movq %%rsp,%0" - : "=r"(pointer)); -#endif - } - printk("The stack for \"%s\"\n", thread->name); - for(count = 0; count < 25 && pointer < bottom; count ++) - { - printk("[0x%lx] 0x%lx\n", pointer, *pointer); - pointer++; - } - - if(pointer < bottom) printk(" ... continues.\n"); -} - -#ifdef __i386__ -#define switch_threads(prev, next) do { \ - unsigned long esi,edi; \ - __asm__ __volatile__("pushfl\n\t" \ - "pushl %%ebp\n\t" \ - "movl %%esp,%0\n\t" /* save ESP */ \ - "movl %4,%%esp\n\t" /* restore ESP */ \ - "movl $1f,%1\n\t" /* save EIP */ \ - "pushl %5\n\t" /* restore EIP */ \ - "ret\n\t" \ - "1:\t" \ - "popl %%ebp\n\t" \ - "popfl" \ - :"=m" (prev->sp),"=m" (prev->ip), \ - "=S" (esi),"=D" (edi) \ - :"m" (next->sp),"m" (next->ip), \ - "2" (prev), "d" (next)); \ -} while (0) -#elif __x86_64__ -#define switch_threads(prev, next) do { \ - unsigned long rsi,rdi; \ - __asm__ __volatile__("pushfq\n\t" \ - "pushq %%rbp\n\t" \ - "movq %%rsp,%0\n\t" /* save RSP */ \ - "movq %4,%%rsp\n\t" /* restore RSP */ \ - "movq $1f,%1\n\t" /* save RIP */ \ - "pushq %5\n\t" /* restore RIP */ \ - "ret\n\t" \ - "1:\t" \ - "popq %%rbp\n\t" \ - "popfq" \ - :"=m" (prev->sp),"=m" (prev->ip), \ - "=S" (rsi),"=D" (rdi) \ - :"m" (next->sp),"m" (next->ip), \ - "2" (prev), "d" (next)); \ -} while (0) -#endif - void inline print_runqueue(void) { struct list_head *it; @@ -142,6 +69,54 @@ void inline print_runqueue(void) printk("\n"); } +/* Find the time when the next timeout expires. If this is more than + 10 seconds from now, return 10 seconds from now. */ +static s_time_t blocking_time(void) +{ + struct thread *thread; + struct list_head *iterator; + s_time_t min_wakeup_time; + unsigned long flags; + local_irq_save(flags); + /* default-block the domain for 10 seconds: */ + min_wakeup_time = NOW() + SECONDS(10); + + /* Thread list needs to be protected */ + list_for_each(iterator, &idle_thread->thread_list) + { + thread = list_entry(iterator, struct thread, thread_list); + if(!is_runnable(thread) && thread->wakeup_time != 0LL) + { + if(thread->wakeup_time < min_wakeup_time) + { + min_wakeup_time = thread->wakeup_time; + } + } + } + local_irq_restore(flags); + return(min_wakeup_time); +} + +/* Wake up all threads with expired timeouts. */ +static void wake_expired(void) +{ + struct thread *thread; + struct list_head *iterator; + s_time_t now = NOW(); + unsigned long flags; + local_irq_save(flags); + /* Thread list needs to be protected */ + list_for_each(iterator, &idle_thread->thread_list) + { + thread = list_entry(iterator, struct thread, thread_list); + if(!is_runnable(thread) && thread->wakeup_time != 0LL) + { + if(thread->wakeup_time <= now) + wake(thread); + } + } + local_irq_restore(flags); +} void schedule(void) { @@ -202,88 +177,39 @@ void exit_thread(void) schedule(); } -/* Pushes the specified value onto the stack of the specified thread */ -static void stack_push(struct thread *thread, unsigned long value) -{ - thread->sp -= sizeof(unsigned long); - *((unsigned long *)thread->sp) = value; -} - -struct thread* create_thread(char *name, void (*function)(void *), void *data) +void block(struct thread *thread) { - struct thread *thread; - unsigned long flags; - - thread = xmalloc(struct thread); - /* Allocate 2 pages for stack, stack will be 2pages aligned */ - thread->stack = (char *)alloc_pages(1); - thread->name = name; - printk("Thread \"%s\": pointer: 0x%lx, stack: 0x%lx\n", name, thread, - thread->stack); - - thread->sp = (unsigned long)thread->stack + 4096 * 2; - /* Save pointer to the thread on the stack, used by current macro */ - *((unsigned long *)thread->stack) = (unsigned long)thread; - - stack_push(thread, (unsigned long) function); - stack_push(thread, (unsigned long) data); - thread->ip = (unsigned long) thread_starter; - - /* Not runable, not exited */ - thread->flags = 0; - set_runnable(thread); - local_irq_save(flags); - if(idle_thread != NULL) { - list_add_tail(&thread->thread_list, &idle_thread->thread_list); - } else if(function != idle_thread_fn) - { - printk("BUG: Not allowed to create thread before initialising scheduler.\n"); - BUG(); - } - local_irq_restore(flags); - return thread; + thread->wakeup_time = 0LL; + clear_runnable(thread); } - -void block(struct thread *thread) +void sleep(u32 millisecs) { + struct thread *thread = get_current(); + thread->wakeup_time = NOW() + MILLISECS(millisecs); clear_runnable(thread); + schedule(); } void wake(struct thread *thread) { + thread->wakeup_time = 0LL; set_runnable(thread); } void idle_thread_fn(void *unused) { + s_time_t until; for(;;) { schedule(); - block_domain(10000); + /* block until the next timeout expires, or for 10 secs, whichever comes first */ + until = blocking_time(); + block_domain(until); + wake_expired(); } } -void run_idle_thread(void) -{ - /* Switch stacks and run the thread */ -#if defined(__i386__) - __asm__ __volatile__("mov %0,%%esp\n\t" - "push %1\n\t" - "ret" - :"=m" (idle_thread->sp) - :"m" (idle_thread->ip)); -#elif defined(__x86_64__) - __asm__ __volatile__("mov %0,%%rsp\n\t" - "push %1\n\t" - "ret" - :"=m" (idle_thread->sp) - :"m" (idle_thread->ip)); -#endif -} - - - DECLARE_MUTEX(mutex); void th_f1(void *data) |