rockbox/uisimulator/sdl/thread-sdl.c
Michael Sevakis 3a45faa6a8 More Simulator tweaking. Back to the counter but with 0 delay. Forget the semaphore; it makes for too much kernel thread yielding.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@14649 a1c6a512-1295-4272-9138-f99709370657
2007-09-09 08:28:42 +00:00

390 lines
8.8 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 Dan Everton
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <time.h>
#include <SDL.h>
#include <SDL_thread.h>
#include <stdlib.h>
#include <memory.h>
#include "thread-sdl.h"
#include "kernel.h"
#include "thread.h"
#include "debug.h"
/* Define this as 1 to show informational messages that are not errors. */
#define THREAD_SDL_DEBUGF_ENABLED 0
#if THREAD_SDL_DEBUGF_ENABLED
#define THREAD_SDL_DEBUGF(...) DEBUGF(__VA_ARGS__)
static char __name[32];
#define THREAD_SDL_GET_NAME(thread) \
({ thread_get_name(__name, sizeof(__name)/sizeof(__name[0]), thread); __name; })
#else
#define THREAD_SDL_DEBUGF(...)
#define THREAD_SDL_GET_NAME(thread)
#endif
#define THREAD_PANICF(str...) \
({ fprintf(stderr, str); exit(-1); })
struct thread_entry threads[MAXTHREADS]; /* Thread entries as in core */
static SDL_mutex *m;
static struct thread_entry *running;
extern long start_tick;
void kill_sim_threads(void)
{
int i;
SDL_LockMutex(m);
for (i = 0; i < MAXTHREADS; i++)
{
struct thread_entry *thread = &threads[i];
if (thread->context.t != NULL)
{
SDL_LockMutex(m);
if (thread->statearg != STATE_RUNNING)
SDL_CondSignal(thread->context.c);
SDL_Delay(10);
SDL_KillThread(thread->context.t);
SDL_DestroyCond(thread->context.c);
}
}
SDL_DestroyMutex(m);
}
static int find_empty_thread_slot(void)
{
int n;
for (n = 0; n < MAXTHREADS; n++)
{
if (threads[n].name == NULL)
break;
}
return n;
}
static void add_to_list(struct thread_entry **list,
struct thread_entry *thread)
{
if (*list == NULL)
{
/* Insert into unoccupied list */
thread->next = thread;
thread->prev = thread;
*list = thread;
}
else
{
/* Insert last */
thread->next = *list;
thread->prev = (*list)->prev;
thread->prev->next = thread;
(*list)->prev = thread;
}
}
static void remove_from_list(struct thread_entry **list,
struct thread_entry *thread)
{
if (thread == thread->next)
{
/* The only item */
*list = NULL;
return;
}
if (thread == *list)
{
/* List becomes next item */
*list = thread->next;
}
/* Fix links to jump over the removed entry. */
thread->prev->next = thread->next;
thread->next->prev = thread->prev;
}
struct thread_entry *thread_get_current(void)
{
return running;
}
void thread_sdl_lock(void)
{
SDL_LockMutex(m);
}
void thread_sdl_unlock(void)
{
SDL_UnlockMutex(m);
}
void switch_thread(bool save_context, struct thread_entry **blocked_list)
{
static int counter = 0;
struct thread_entry *current = running;
SDL_UnlockMutex(m);
if (counter++ >= 50)
{
SDL_Delay(0);
counter = 0;
}
SDL_LockMutex(m);
running = current;
(void)save_context; (void)blocked_list;
}
void sleep_thread(int ticks)
{
struct thread_entry *current;
int rem;
current = running;
current->statearg = STATE_SLEEPING;
rem = (SDL_GetTicks() - start_tick) % (1000/HZ);
if (rem < 0)
rem = 0;
SDL_UnlockMutex(m);
SDL_Delay((1000/HZ) * ticks + ((1000/HZ)-1) - rem);
SDL_LockMutex(m);
running = current;
current->statearg = STATE_RUNNING;
}
int runthread(void *data)
{
struct thread_entry *current;
/* Cannot access thread variables before locking the mutex as the
data structures may not be filled-in yet. */
SDL_LockMutex(m);
running = (struct thread_entry *)data;
current = running;
current->context.start();
THREAD_SDL_DEBUGF("Thread Done: %d (%s)\n",
current - threads, THREAD_SDL_GET_NAME(current));
remove_thread(NULL);
return 0;
}
struct thread_entry*
create_thread(void (*function)(void), void* stack, int stack_size,
const char *name)
{
/** Avoid compiler warnings */
SDL_Thread* t;
SDL_cond *cond;
int slot;
THREAD_SDL_DEBUGF("Creating thread: (%s)\n", name ? name : "");
slot = find_empty_thread_slot();
if (slot >= MAXTHREADS)
{
DEBUGF("Failed to find thread slot\n");
return NULL;
}
cond = SDL_CreateCond();
if (cond == NULL)
{
DEBUGF("Failed to create condition variable\n");
return NULL;
}
t = SDL_CreateThread(runthread, &threads[slot]);
if (t == NULL)
{
DEBUGF("Failed to create SDL thread\n");
SDL_DestroyCond(cond);
return NULL;
}
threads[slot].stack = stack;
threads[slot].stack_size = stack_size;
threads[slot].name = name;
threads[slot].statearg = STATE_RUNNING;
threads[slot].context.start = function;
threads[slot].context.t = t;
threads[slot].context.c = cond;
THREAD_SDL_DEBUGF("New Thread: %d (%s)\n",
slot, THREAD_SDL_GET_NAME(&threads[slot]));
return &threads[slot];
}
void block_thread(struct thread_entry **list)
{
struct thread_entry *thread = running;
thread->statearg = STATE_BLOCKED;
add_to_list(list, thread);
SDL_CondWait(thread->context.c, m);
running = thread;
}
void block_thread_w_tmo(struct thread_entry **list, int ticks)
{
struct thread_entry *thread = running;
thread->statearg = STATE_BLOCKED_W_TMO;
add_to_list(list, thread);
SDL_CondWaitTimeout(thread->context.c, m, (1000/HZ) * ticks);
running = thread;
if (thread->statearg == STATE_BLOCKED_W_TMO)
{
/* Timed out */
remove_from_list(list, thread);
thread->statearg = STATE_RUNNING;
}
}
void wakeup_thread(struct thread_entry **list)
{
struct thread_entry *thread = *list;
if (thread == NULL)
{
return;
}
switch (thread->statearg)
{
case STATE_BLOCKED:
case STATE_BLOCKED_W_TMO:
remove_from_list(list, thread);
thread->statearg = STATE_RUNNING;
SDL_CondSignal(thread->context.c);
break;
}
}
void init_threads(void)
{
int slot;
m = SDL_CreateMutex();
memset(threads, 0, sizeof(threads));
slot = find_empty_thread_slot();
if (slot >= MAXTHREADS)
{
THREAD_PANICF("Couldn't find slot for main thread.\n");
}
threads[slot].stack = " ";
threads[slot].stack_size = 8;
threads[slot].name = "main";
threads[slot].statearg = STATE_RUNNING;
threads[slot].context.t = gui_thread;
threads[slot].context.c = SDL_CreateCond();
running = &threads[slot];
THREAD_SDL_DEBUGF("First Thread: %d (%s)\n",
slot, THREAD_SDL_GET_NAME(&threads[slot]));
if (SDL_LockMutex(m) == -1) {
THREAD_PANICF("Couldn't lock mutex\n");
}
}
void remove_thread(struct thread_entry *thread)
{
struct thread_entry *current = running;
SDL_Thread *t;
SDL_cond *c;
if (thread == NULL)
{
thread = current;
}
t = thread->context.t;
c = thread->context.c;
thread->context.t = NULL;
if (thread != current)
{
if (thread->statearg != STATE_RUNNING)
SDL_CondSignal(c);
}
THREAD_SDL_DEBUGF("Removing thread: %d (%s)\n",
thread - threads, THREAD_SDL_GET_NAME(thread));
thread->name = NULL;
SDL_DestroyCond(c);
if (thread == current)
{
SDL_UnlockMutex(m);
}
SDL_KillThread(t);
}
int thread_stack_usage(const struct thread_entry *thread)
{
return 50;
(void)thread;
}
int thread_get_status(const struct thread_entry *thread)
{
return thread->statearg;
}
/* Return name if one or ID if none */
void thread_get_name(char *buffer, int size,
struct thread_entry *thread)
{
if (size <= 0)
return;
*buffer = '\0';
if (thread)
{
/* Display thread name if one or ID if none */
bool named = thread->name && *thread->name;
const char *fmt = named ? "%s" : "%08lX";
intptr_t name = named ?
(intptr_t)thread->name : (intptr_t)thread;
snprintf(buffer, size, fmt, name);
}
}