Subversion Repositories freemyipod

//

//

//    Copyright 2010 TheSeven

//

//

//    This file is part of emCORE.

//

//    emCORE is free software: you can redistribute it and/or

//    modify it under the terms of the GNU General Public License as

//    published by the Free Software Foundation, either version 2 of the

//    License, or (at your option) any later version.

//

//    emCORE is distributed in the hope that it will be useful,

//    but WITHOUT ANY WARRANTY; without even the implied warranty of

//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

//    See the GNU General Public License for more details.

//

//    You should have received a copy of the GNU General Public License along

//    with emCORE.  If not, see <http://www.gnu.org/licenses/>.

//

//

#include "global.h"

#include "thread.h"

#include "timer.h"

#include "panic.h"

#include "util.h"

#include "malloc.h"

#ifdef HAVE_STORAGE

#include "dir.h"

#include "file.h"

#endif

#ifdef HAVE_BUTTON

#include "button.h"

#endif

struct scheduler_thread* head_thread IBSS_ATTR;

struct scheduler_thread* current_thread IBSS_ATTR;

struct scheduler_thread idle_thread IBSS_ATTR;

uint32_t last_tick IBSS_ATTR;

bool scheduler_frozen IBSS_ATTR;

extern struct wakeup dbgwakeup;

void mutex_init(struct mutex* obj)

{

    memset(obj, 0, sizeof(struct mutex));

}

void mutex_add_to_queue(struct mutex* obj, struct scheduler_thread* thread)

{

    struct scheduler_thread* t;

    if (!obj->waiters || obj->waiters->priority <= thread->priority)

    {

        thread->queue_next = obj->waiters;

        obj->waiters = thread;

    }

    else

    {

        t = obj->waiters;

        while (t->queue_next && t->queue_next->priority > thread->priority)

            t = t->queue_next;

        thread->queue_next = t->queue_next;

        t->queue_next = thread;

    }

}

void mutex_remove_from_queue(struct mutex* obj, struct scheduler_thread* thread)

{

    struct scheduler_thread* t;

    if (!obj->waiters) return;

    if (obj->waiters == thread) obj->waiters = thread->queue_next;

    else

    {

        t = obj->waiters;

        while (t->queue_next)

        {

            if (t->queue_next == thread) t->queue_next = thread->queue_next;

            t = t->queue_next;

        }

    }

}

int mutex_lock(struct mutex* obj, int timeout)

{

    int ret = THREAD_OK;

    uint32_t mode = enter_critical_section();

    if (!obj->count)

    {

        obj->count = 1;

        obj->owner = current_thread;

    }

    else if (obj->owner == current_thread) obj->count++;

    else

    {

        if (timeout)

        {

            current_thread->state = THREAD_BLOCKED;

            current_thread->block_type = THREAD_BLOCK_MUTEX;

            current_thread->blocked_by = obj;

            current_thread->timeout = timeout;

            current_thread->blocked_since = USEC_TIMER;

            mutex_add_to_queue(obj, current_thread);

            leave_critical_section(mode);

            context_switch();

            if (obj->owner != current_thread) return THREAD_TIMEOUT;

            return THREAD_OK;

        }

        else ret = THREAD_TIMEOUT;

    }

    leave_critical_section(mode);

    return ret;

}

int mutex_unlock(struct mutex* obj)

{

    int ret = THREAD_OK;

    uint32_t mode = enter_critical_section();

    if (!obj->count)

    {

        leave_critical_section(mode);

        panicf(PANIC_KILLTHREAD, "Trying to unlock non-owned mutex! (%08X)", obj);

    }

    if (obj->owner != current_thread)

    {

        leave_critical_section(mode);

        panicf(PANIC_KILLTHREAD, "Trying to unlock mutex owned by different thread! (%08X)", obj);

    }

    if (--(obj->count)) ret = obj->count;

    else if (obj->waiters)

    {

        obj->count = 1;

        obj->owner = obj->waiters;

        obj->waiters->state = THREAD_READY;

        obj->waiters->block_type = THREAD_NOT_BLOCKED;

        obj->waiters->blocked_by = NULL;

        obj->waiters->timeout = 0;

        obj->waiters = obj->waiters->queue_next;

    }

    leave_critical_section(mode);

    return ret;

}

void wakeup_init(struct wakeup* obj)

{

    memset(obj, 0, sizeof(struct wakeup));

}

int wakeup_wait(struct wakeup* obj, int timeout)

{

    int ret = THREAD_OK;

    uint32_t mode = enter_critical_section();

    if (obj->waiter)

    {

        leave_critical_section(mode);

        panicf(PANIC_KILLTHREAD, "Multiple threads waiting single wakeup! (%08X)", obj);

    }

    if (obj->signalled) obj->signalled = false;

    else

    {

        if (timeout)

        {

            current_thread->state = THREAD_BLOCKED;

            current_thread->block_type = THREAD_BLOCK_WAKEUP;

            current_thread->blocked_by = obj;

            current_thread->timeout = timeout;

            current_thread->blocked_since = USEC_TIMER;

            obj->waiter = current_thread;

            leave_critical_section(mode);

            context_switch();

            obj->waiter = NULL;

            if (!obj->signalled) return THREAD_TIMEOUT;

            obj->signalled = false;

            return THREAD_OK;

        }

        else ret = THREAD_TIMEOUT;

    }

    leave_critical_section(mode);

    return ret;

}

int wakeup_signal(struct wakeup* obj)

{

    int ret = THREAD_OK;

    uint32_t mode = enter_critical_section();

    obj->signalled = true;

    if (obj->waiter)

    {

        obj->waiter->state = THREAD_READY;

        obj->waiter->block_type = THREAD_NOT_BLOCKED;

        obj->waiter->blocked_by = NULL;

        obj->waiter->timeout = 0;

        ret = THREAD_FOUND;

    }

    leave_critical_section(mode);

    return ret;

}

void sleep(int usecs)

{

    if (usecs)

    {

        uint32_t mode = enter_critical_section();

        current_thread->state = THREAD_BLOCKED;

        current_thread->block_type = THREAD_BLOCK_SLEEP;

        current_thread->timeout = usecs;

        current_thread->blocked_since = USEC_TIMER;

        leave_critical_section(mode);

    }

    context_switch();

}

void scheduler_init(void)

{

    last_tick = USEC_TIMER;

    scheduler_frozen = false;

    head_thread = &idle_thread;

    current_thread = &idle_thread;

    memset(&idle_thread, 0, sizeof(idle_thread));

    idle_thread.state = THREAD_RUNNING;

    idle_thread.startusec = last_tick;

    idle_thread.name = "idle thread";

    idle_thread.stack = (uint32_t*)-1;

    setup_tick();

}

bool scheduler_freeze(bool value)

{

    bool old = scheduler_frozen;

    scheduler_frozen = value;

    return old;

}

void scheduler_pause_accounting()

{

    uint32_t usec = USEC_TIMER;

    current_thread->cputime_total += usec - current_thread->startusec;

    current_thread->cputime_current += usec - current_thread->startusec;

}

void scheduler_resume_accounting()

{

    current_thread->startusec = USEC_TIMER;

}

void scheduler_switch(struct scheduler_thread* thread)

{

    struct scheduler_thread* t;

    uint32_t score, best;

    uint32_t usec = USEC_TIMER;

    if (current_thread->state == THREAD_RUNNING) current_thread->state = THREAD_READY;

    if ((int)current_thread->stack != -1 && *current_thread->stack != 0xaffebeaf)

    {

        for (t = head_thread; t; t = t->thread_next)

            if (t->type == USER_THREAD)

                t->state = THREAD_SUSPENDED;

        current_thread->state = THREAD_DEFUNCT;

        current_thread->block_type = THREAD_DEFUNCT_STKOV;

        wakeup_signal(&dbgwakeup);

    }

    if (usec - last_tick > SCHEDULER_TICK)

    {

        uint32_t diff = usec - last_tick;

        last_tick = usec;

        for (t = head_thread; t; t = t->thread_next)

        {

            t->cpuload = 255 * t->cputime_current / diff;

            t->cputime_current = 0;

        }

    }

    if (scheduler_frozen) thread = &idle_thread;

    else

    {

        for (t = head_thread; t; t = t->thread_next)

            if (t->state == THREAD_BLOCKED && t->timeout != -1

             && TIME_AFTER(usec, t->blocked_since + t->timeout))

            {

                if (t->block_type == THREAD_BLOCK_MUTEX)

                    mutex_remove_from_queue((struct mutex*)t->blocked_by, t);

                t->state = THREAD_READY;

                t->block_type = THREAD_NOT_BLOCKED;

                t->blocked_by = NULL;

                t->timeout = 0;

            }

        if (thread && thread->state == THREAD_READY) current_thread = thread;

        else

        {

            thread = &idle_thread;

            best = 0xffffffff;

            for (t = head_thread; t; t = t->thread_next)

                if (t->state == THREAD_READY && t->priority)

                {

                    score = t->cputime_current / t->priority;

                    if (score < best)

                    {

                        best = score;

                        thread = t;

                    }

                }

        }

    }

    current_thread = thread;

    current_thread->state = THREAD_RUNNING;

}

struct scheduler_thread* thread_create(struct scheduler_thread* thread, const char* name,

                                       const void* code, void* stack, int stacksize,

                                       enum thread_type type, int priority, bool run)

{

    bool stack_alloced = false;

    bool thread_alloced = false;

    if (!stack)

    {

        stack = malloc(stacksize);

        stack_alloced = true;

    }

    if (!stack) return NULL;

    if (!thread)

    {

        thread = (struct scheduler_thread*)malloc(sizeof(struct scheduler_thread));

        thread_alloced = true;

    }

    if (!thread)

    {

        if (stack_alloced) free(stack);

        return NULL;

    }

    if (thread_alloced) reownalloc(thread, thread);

    if (stack_alloced) reownalloc(stack, thread);

    int i;

    for (i = 0; i < stacksize >> 2; i ++) ((uint32_t*)stack)[i] = 0xaffebeaf;

    memset(thread, 0, sizeof(struct scheduler_thread));

    thread->state = run ? THREAD_READY : THREAD_SUSPENDED;

    thread->type = type;

    thread->name = name;

    thread->priority = priority;

    thread->cpsr = 0x1f;

    thread->regs[15] = (uint32_t)code;

    thread->regs[14] = (uint32_t)thread_exit;

    thread->regs[13] = (uint32_t)stack + stacksize;

    thread->stack = stack;

    uint32_t mode = enter_critical_section();

    thread->thread_next = head_thread;

    head_thread = thread;

    leave_critical_section(mode);

    return thread;

}

int thread_suspend(struct scheduler_thread* thread)

{

    int ret = THREAD_OK;

    bool needsswitch = false;

    uint32_t mode = enter_critical_section();

    if (!thread) thread = current_thread;

    if (thread->state == THREAD_SUSPENDED) ret = ALREADY_SUSPENDED;

    if (ret == THREAD_OK)

    {

        if (thread->state == THREAD_RUNNING) needsswitch = true;

        else if (thread->state == THREAD_BLOCKED)

        {

            if (thread->block_type == THREAD_BLOCK_SLEEP)

            {

                if (thread->timeout != -1) thread->timeout -= USEC_TIMER - thread->blocked_since;

            }

            else if (thread->block_type == THREAD_BLOCK_MUTEX)

            {

                mutex_remove_from_queue((struct mutex*)thread->blocked_by, thread);

                if (thread->timeout != -1) thread->timeout -= USEC_TIMER - thread->blocked_since;

            }

            else if (thread->block_type == THREAD_BLOCK_WAKEUP)

            {

                if (thread->timeout != -1) thread->timeout -= USEC_TIMER - thread->blocked_since;

            }

        }

        thread->state = THREAD_SUSPENDED;

    }

    leave_critical_section(mode);

    if (needsswitch) context_switch();

    return ret;

}

int thread_resume(struct scheduler_thread* thread)

{

    int ret = THREAD_OK;

    bool needsswitch = false;

    uint32_t mode = enter_critical_section();

    if (!thread) thread = current_thread;

    if (thread->state != THREAD_SUSPENDED) ret = ALREADY_RESUMED;

    if (ret == THREAD_OK)

    {

        if (thread->block_type == THREAD_BLOCK_SLEEP)

            thread->blocked_since = USEC_TIMER;

        else if (thread->block_type == THREAD_BLOCK_MUTEX)

        {

            mutex_add_to_queue((struct mutex*)thread->blocked_by, thread);

            thread->blocked_since = USEC_TIMER;

            thread->state = THREAD_BLOCKED;

        }

        else if (thread->block_type == THREAD_BLOCK_WAKEUP)

        {

            thread->blocked_since = USEC_TIMER;

            thread->state = THREAD_BLOCKED;

        }

        else thread->state = THREAD_READY;

    }

    leave_critical_section(mode);

    return ret;

}

void thread_set_name(struct scheduler_thread* thread, char* name)

{

    uint32_t mode = enter_critical_section();

    if (!thread) thread = current_thread;

    thread->name = name;

    leave_critical_section(mode);

}

void thread_set_priority(struct scheduler_thread* thread, int priority)

{

    uint32_t mode = enter_critical_section();

    if (!thread) thread = current_thread;

    thread->priority = priority;

    leave_critical_section(mode);

}

int thread_terminate(struct scheduler_thread* thread)

{

    struct scheduler_thread* t;

    bool needsswitch = false;

    uint32_t mode = enter_critical_section();

    if (!thread) thread = current_thread;

    if (thread->state == THREAD_RUNNING) needsswitch = true;

    else if (thread->state == THREAD_BLOCKED)

    {

        if (thread->block_type == THREAD_BLOCK_MUTEX)

            mutex_remove_from_queue((struct mutex*)t->blocked_by, thread);

        else if (thread->block_type == THREAD_BLOCK_WAKEUP)

            ((struct wakeup*)thread->blocked_by)->waiter = NULL;

    }

    for (t = head_thread; t && t->thread_next != thread; t = t->thread_next);

    if (t) t->thread_next = thread->thread_next;

    leave_critical_section(mode);

#ifdef HAVE_STORAGE

    close_all_of_process(thread);

    closedir_all_of_process(thread);

#endif

#ifdef HAVE_BUTTON

    button_unregister_all_of_thread(thread);

#endif

    free_all_of_thread(thread);

    if (needsswitch) context_switch();

    return THREAD_OK;

}

int thread_killlevel(enum thread_type type, bool killself)

{

    struct scheduler_thread* t;

    int count = 0;

    uint32_t mode = enter_critical_section();

    for (t = head_thread; t; t = t->thread_next);

        if (t->type <= type && (killself || current_thread != t))

        {

            thread_terminate(t);

            count++;

        }

    leave_critical_section(mode);

    return count;

}

enum thread_state thread_get_state(struct scheduler_thread* thread)

{

    return thread->state;

}

void thread_exit()

{

    thread_terminate(NULL);

}

int* __errno()

{

    return &current_thread->err_no;

}