//============================================================
//
// sdlwork.c - SDL OSD core work item functions
//
// Copyright (c) 1996-2010, Nicola Salmoria and the MAME Team.
// Visit http://mamedev.org for licensing and usage restrictions.
//
// SDLMAME by Olivier Galibert and R. Belmont
//
//============================================================
#if defined(SDLMAME_NOASM)
/* must be exported
* FIXME: NOASM should be taken care of in sdlsync.c
* This is not really a sound solution.
*/
int osd_num_processors = 0;
#include "../osdmini/miniwork.c"
#else
#include "osdcore.h"
#include "osinline.h"
#include "sdlsync.h"
#include "sdlos.h"
#include "eminline.h"
#if defined(SDLMAME_MACOSX)
#include "osxutils.h"
#endif
//============================================================
// DEBUGGING
//============================================================
#define KEEP_STATISTICS (0)
//============================================================
// PARAMETERS
//============================================================
#define SDLENV_PROCESSORS "OSDPROCESSORS"
#define SDLENV_CPUMASKS "OSDCPUMASKS"
#define INFINITE (osd_ticks_per_second() * (osd_ticks_t) 10000)
#define SPIN_LOOP_TIME (osd_ticks_per_second() / 10000)
//============================================================
// MACROS
//============================================================
#if KEEP_STATISTICS
#define add_to_stat(v,x) do { atomic_add32((v), (x)); } while (0)
#define begin_timing(v) do { (v) -= get_profile_ticks(); } while (0)
#define end_timing(v) do { (v) += get_profile_ticks(); } while (0)
#else
#define add_to_stat(v,x) do { } while (0)
#define begin_timing(v) do { } while (0)
#define end_timing(v) do { } while (0)
#endif
//============================================================
// TYPE DEFINITIONS
//============================================================
struct work_thread_info
{
osd_work_queue * queue; // pointer back to the queue
osd_thread * handle; // handle to the thread
osd_event * wakeevent; // wake event for the thread
volatile INT32 active; // are we actively processing work?
#if KEEP_STATISTICS
INT32 itemsdone;
osd_ticks_t actruntime;
osd_ticks_t runtime;
osd_ticks_t spintime;
osd_ticks_t waittime;
#endif
};
struct osd_work_queue
{
osd_scalable_lock * lock; // lock for protecting the queue
osd_work_item * volatile list; // list of items in the queue
osd_work_item ** volatile tailptr; // pointer to the tail pointer of work items in the queue
osd_work_item * volatile free; // free list of work items
volatile INT32 items; // items in the queue
volatile INT32 livethreads; // number of live threads
volatile INT32 waiting; // is someone waiting on the queue to complete?
volatile UINT8 exiting; // should the threads exit on their next opportunity?
UINT32 threads; // number of threads in this queue
UINT32 flags; // creation flags
work_thread_info * thread; // array of thread information
osd_event * doneevent; // event signalled when work is complete
#if KEEP_STATISTICS
volatile INT32 itemsqueued; // total items queued
volatile INT32 setevents; // number of times we called SetEvent
volatile INT32 extraitems; // how many extra items we got after the first in the queue loop
volatile INT32 spinloops; // how many times spinning bought us more items
#endif
};
struct osd_work_item
{
osd_work_item * next; // pointer to next item
osd_work_queue * queue; // pointer back to the owning queue
osd_work_callback callback; // callback function
void * param; // callback parameter
void * result; // callback result
osd_event * event; // event signalled when complete
UINT32 flags; // creation flags
volatile INT32 done; // is the item done?
};
typedef void *PVOID;
//============================================================
// GLOBAL VARIABLES
//============================================================
int osd_num_processors = 0;
//============================================================
// FUNCTION PROTOTYPES
//============================================================
static int effective_num_processors(void);
static UINT32 effective_cpu_mask(int index);
static void * worker_thread_entry(void *param);
static void worker_thread_process(osd_work_queue *queue, work_thread_info *thread);
//============================================================
// osd_work_queue_alloc
//============================================================
osd_work_queue *osd_work_queue_alloc(int flags)
{
int numprocs = effective_num_processors();
osd_work_queue *queue;
int threadnum;
// allocate a new queue
queue = (osd_work_queue *)osd_malloc(sizeof(*queue));
if (queue == NULL)
goto error;
memset(queue, 0, sizeof(*queue));
// initialize basic queue members
queue->tailptr = (osd_work_item **)&queue->list;
queue->flags = flags;
// allocate events for the queue
queue->doneevent = osd_event_alloc(TRUE, TRUE); // manual reset, signalled
if (queue->doneevent == NULL)
goto error;
// initialize the critical section
queue->lock = osd_scalable_lock_alloc();
if (queue->lock == NULL)
goto error;
// determine how many threads to create...
// on a single-CPU system, create 1 thread for I/O queues, and 0 threads for everything else
if (numprocs == 1)
queue->threads = (flags & WORK_QUEUE_FLAG_IO) ? 1 : 0;
// on an n-CPU system, create (n-1) threads for multi queues, and 1 thread for everything else
else
queue->threads = (flags & WORK_QUEUE_FLAG_MULTI) ? (numprocs - 1) : 1;
// clamp to the maximum
queue->threads = MIN(queue->threads, WORK_MAX_THREADS);
// allocate memory for thread array (+1 to count the calling thread)
queue->thread = (work_thread_info *)osd_malloc_array((queue->threads + 1) * sizeof(queue->thread[0]));
if (queue->thread == NULL)
goto error;
memset(queue->thread, 0, (queue->threads + 1) * sizeof(queue->thread[0]));
// iterate over threads
for (threadnum = 0; threadnum < queue->threads; threadnum++)
{
work_thread_info *thread = &queue->thread[threadnum];
// set a pointer back to the queue
thread->queue = queue;
// create the per-thread wake event
thread->wakeevent = osd_event_alloc(FALSE, FALSE); // auto-reset, not signalled
if (thread->wakeevent == NULL)
goto error;
// create the thread
thread->handle = osd_thread_create(worker_thread_entry, thread);
if (thread->handle == NULL)
goto error;
// set its priority: I/O threads get high priority because they are assumed to be
// blocked most of the time; other threads just match the creator's priority
if (flags & WORK_QUEUE_FLAG_IO)
osd_thread_adjust_priority(thread->handle, 1);
else
osd_thread_adjust_priority(thread->handle, 0);
// Bind main thread to cpu 0
osd_thread_cpu_affinity(NULL, effective_cpu_mask(0));
if (flags & WORK_QUEUE_FLAG_IO)
osd_thread_cpu_affinity(thread->handle, effective_cpu_mask(1));
else
osd_thread_cpu_affinity(thread->handle, effective_cpu_mask(2+threadnum) );
}
// start a timer going for "waittime" on the main thread
begin_timing(queue->thread[queue->threads].waittime);
return queue;
error:
osd_work_queue_free(queue);
return NULL;
}
//============================================================
// osd_work_queue_items
//============================================================
int osd_work_queue_items(osd_work_queue *queue)
{
// return the number of items currently in the queue
return queue->items;
}
//============================================================
// osd_work_queue_wait
//============================================================
int osd_work_queue_wait(osd_work_queue *queue, osd_ticks_t timeout)
{
// if no threads, no waiting
if (queue->threads == 0)
return TRUE;
// if no items, we're done
if (queue->items == 0)
return TRUE;
// if this is a multi queue, help out rather than doing nothing
if (queue->flags & WORK_QUEUE_FLAG_MULTI)
{
work_thread_info *thread = &queue->thread[queue->threads];
end_timing(thread->waittime);
// process what we can as a worker thread
worker_thread_process(queue, thread);
// if we're a high frequency queue, spin until done
if (queue->flags & WORK_QUEUE_FLAG_HIGH_FREQ && queue->items != 0)
{
osd_ticks_t stopspin = osd_ticks() + timeout;
// spin until we're done
begin_timing(thread->spintime);
do {
int spin = 10000;
while (--spin && queue->items != 0)
osd_yield_processor();
} while (queue->items != 0 && osd_ticks() < stopspin);
end_timing(thread->spintime);
begin_timing(thread->waittime);
return (queue->items == 0);
}
begin_timing(thread->waittime);
}
// reset our done event and double-check the items before waiting
osd_event_reset(queue->doneevent);
atomic_exchange32(&queue->waiting, TRUE);
if (queue->items != 0)
osd_event_wait(queue->doneevent, timeout);
atomic_exchange32(&queue->waiting, FALSE);
// return TRUE if we actually hit 0
return (queue->items == 0);
}
//============================================================
// osd_work_queue_free
//============================================================
void osd_work_queue_free(osd_work_queue *queue)
{
// if we have threads, clean them up
if (queue->thread != NULL)
{
int threadnum;
// stop the timer for "waittime" on the main thread
end_timing(queue->thread[queue->threads].waittime);
// signal all the threads to exit
queue->exiting = TRUE;
for (threadnum = 0; threadnum < queue->threads; threadnum++)
{
work_thread_info *thread = &queue->thread[threadnum];
if (thread->wakeevent != NULL)
osd_event_set(thread->wakeevent);
}
// wait for all the threads to go away
for (threadnum = 0; threadnum < queue->threads; threadnum++)
{
work_thread_info *thread = &queue->thread[threadnum];
// block on the thread going away, then close the handle
if (thread->handle != NULL)
{
osd_thread_wait_free(thread->handle);
}
// clean up the wake event
if (thread->wakeevent != NULL)
osd_event_free(thread->wakeevent);
}
#if KEEP_STATISTICS
// output per-thread statistics
for (threadnum = 0; threadnum <= queue->threads; threadnum++)
{
work_thread_info *thread = &queue->thread[threadnum];
osd_ticks_t total = thread->runtime + thread->waittime + thread->spintime;
printf("Thread %d: items=%9d run=%5.2f%% (%5.2f%%) spin=%5.2f%% wait/other=%5.2f%% total=%9d\n",
threadnum, thread->itemsdone,
(double)thread->runtime * 100.0 / (double)total,
(double)thread->actruntime * 100.0 / (double)total,
(double)thread->spintime * 100.0 / (double)total,
(double)thread->waittime * 100.0 / (double)total,
(UINT32) total);
}
#endif
}
// free the list
if (queue->thread != NULL)
osd_free(queue->thread);
// free all the events
if (queue->doneevent != NULL)
osd_event_free(queue->doneevent);
// free all items in the free list
while (queue->free != NULL)
{
osd_work_item *item = (osd_work_item *)queue->free;
queue->free = item->next;
if (item->event != NULL)
osd_event_free(item->event);
osd_free(item);
}
// free all items in the active list
while (queue->list != NULL)
{
osd_work_item *item = (osd_work_item *)queue->list;
queue->list = item->next;
if (item->event != NULL)
osd_event_free(item->event);
osd_free(item);
}
#if KEEP_STATISTICS
printf("Items queued = %9d\n", queue->itemsqueued);
printf("SetEvent calls = %9d\n", queue->setevents);
printf("Extra items = %9d\n", queue->extraitems);
printf("Spin loops = %9d\n", queue->spinloops);
#endif
osd_scalable_lock_free(queue->lock);
// free the queue itself
osd_free(queue);
}
//============================================================
// osd_work_item_queue_multiple
//============================================================
osd_work_item *osd_work_item_queue_multiple(osd_work_queue *queue, osd_work_callback callback, INT32 numitems, void *parambase, INT32 paramstep, UINT32 flags)
{
osd_work_item *itemlist = NULL, *lastitem = NULL;
osd_work_item **item_tailptr = &itemlist;
INT32 lockslot;
int itemnum;
// loop over items, building up a local list of work
for (itemnum = 0; itemnum < numitems; itemnum++)
{
osd_work_item *item;
// first allocate a new work item; try the free list first
do
{
item = (osd_work_item *)queue->free;
} while (item != NULL && compare_exchange_ptr((PVOID volatile *)&queue->free, item, item->next) != item);
// if nothing, allocate something new
if (item == NULL)
{
// allocate the item
item = (osd_work_item *)osd_malloc(sizeof(*item));
if (item == NULL)
return NULL;
item->event = NULL;
item->queue = queue;
}
// fill in the basics
item->next = NULL;
item->callback = callback;
item->param = parambase;
item->result = NULL;
item->flags = flags;
item->done = FALSE;
// advance to the next
lastitem = item;
*item_tailptr = item;
item_tailptr = &item->next;
parambase = (UINT8 *)parambase + paramstep;
}
// enqueue the whole thing within the critical section
lockslot = osd_scalable_lock_acquire(queue->lock);
*queue->tailptr = itemlist;
queue->tailptr = item_tailptr;
osd_scalable_lock_release(queue->lock, lockslot);
// increment the number of items in the queue
atomic_add32(&queue->items, numitems);
add_to_stat(&queue->itemsqueued, numitems);
// look for free threads to do the work
if (queue->livethreads < queue->threads)
{
int threadnum;
// iterate over all the threads
for (threadnum = 0; threadnum < queue->threads; threadnum++)
{
work_thread_info *thread = &queue->thread[threadnum];
// if this thread is not active, wake him up
if (!thread->active)
{
osd_event_set(thread->wakeevent);
add_to_stat(&queue->setevents, 1);
// for non-shared, the first one we find is good enough
if (--numitems == 0)
break;
}
}
}
// if no threads, run the queue now on this thread
if (queue->threads == 0)
{
end_timing(queue->thread[0].waittime);
worker_thread_process(queue, &queue->thread[0]);
begin_timing(queue->thread[0].waittime);
}
// only return the item if it won't get released automatically
return (flags & WORK_ITEM_FLAG_AUTO_RELEASE) ? NULL : lastitem;
}
//============================================================
// osd_work_item_wait
//============================================================
int osd_work_item_wait(osd_work_item *item, osd_ticks_t timeout)
{
// if we're done already, just return
if (item->done)
return TRUE;
// if we don't have an event, create one
if (item->event == NULL)
item->event = osd_event_alloc(TRUE, FALSE); // manual reset, not signalled
else
osd_event_reset(item->event);
// if we don't have an event, we need to spin (shouldn't ever really happen)
if (item->event == NULL)
{
osd_ticks_t stopspin = osd_ticks() + timeout;
do {
int spin = 10000;
while (--spin && !item->done)
osd_yield_processor();
} while (!item->done && osd_ticks() < stopspin);
}
// otherwise, block on the event until done
else if (!item->done)
osd_event_wait(item->event, timeout);
// return TRUE if the refcount actually hit 0
return item->done;
}
//============================================================
// osd_work_item_result
//============================================================
void *osd_work_item_result(osd_work_item *item)
{
return item->result;
}
//============================================================
// osd_work_item_release
//============================================================
void osd_work_item_release(osd_work_item *item)
{
osd_work_item *next;
// make sure we're done first
osd_work_item_wait(item, 100 * osd_ticks_per_second());
// add us to the free list on our queue
do
{
next = (osd_work_item *)item->queue->free;
item->next = next;
} while (compare_exchange_ptr((PVOID volatile *)&item->queue->free, next, item) != next);
}
//============================================================
// effective_num_processors
//============================================================
static int effective_num_processors(void)
{
char *procsoverride;
int numprocs = 0;
int physprocs = osd_get_num_processors();
// osd_num_processors == 0 for 'auto'
if (osd_num_processors > 0)
return MIN(4 * physprocs, osd_num_processors);
else
{
// if the OSDPROCESSORS environment variable is set, use that value if valid
procsoverride = osd_getenv(SDLENV_PROCESSORS);
if (procsoverride != NULL && sscanf(procsoverride, "%d", &numprocs) == 1 && numprocs > 0)
return MIN(4 * physprocs, numprocs);
// otherwise, return the info from the system
return physprocs;
}
}
//============================================================
// effective_cpu_mask
//============================================================
static UINT32 effective_cpu_mask(int index)
{
char *s;
char buf[5];
UINT32 mask = 0xFFFF;
s = osd_getenv(SDLENV_CPUMASKS);
if (s != NULL && strcmp(s,"none"))
{
if (!strcmp(s,"auto"))
{
if (index<2)
mask = 0x01; /* main thread and io threads on cpu #0 */
else
mask = (1 << (((index - 1) % (osd_get_num_processors() - 1)) + 1));
}
else
{
if (strlen(s) % 4 != 0 || strlen(s) < (index+1)*4)
{
fprintf(stderr,"Invalid cpu mask @index %d: %s\n", index, s);
}
else
{
memcpy(buf,s+4*index,4);
buf[4] = 0;
if (sscanf(buf, "%04x", &mask) != 1)
fprintf(stderr,"Invalid cpu mask element %d: %s\n", index, buf);
}
}
}
return mask;
}
//============================================================
// worker_thread_entry
//============================================================
static void *worker_thread_entry(void *param)
{
work_thread_info *thread = (work_thread_info *)param;
osd_work_queue *queue = thread->queue;
#if defined(SDLMAME_MACOSX)
void *arp = NewAutoreleasePool();
#endif
// loop until we exit
for ( ;; )
{
// block waiting for work or exit
// bail on exit, and only wait if there are no pending items in queue
if (!queue->exiting && queue->list == NULL)
{
begin_timing(thread->waittime);
osd_event_wait(thread->wakeevent, INFINITE);
end_timing(thread->waittime);
}
if (queue->exiting)
break;
// indicate that we are live
atomic_exchange32(&thread->active, TRUE);
atomic_increment32(&queue->livethreads);
// process work items
for ( ;; )
{
osd_ticks_t stopspin;
// process as much as we can
worker_thread_process(queue, thread);
// if we're a high frequency queue, spin for a while before giving up
if (queue->flags & WORK_QUEUE_FLAG_HIGH_FREQ && queue->list == NULL)
{
// spin for a while looking for more work
begin_timing(thread->spintime);
stopspin = osd_ticks() + SPIN_LOOP_TIME;
do {
int spin = 10000;
while (--spin && queue->list == NULL)
osd_yield_processor();
} while (queue->list == NULL && osd_ticks() < stopspin);
end_timing(thread->spintime);
}
// if nothing more, release the processor
if (queue->list == NULL)
break;
add_to_stat(&queue->spinloops, 1);
}
// decrement the live thread count
atomic_exchange32(&thread->active, FALSE);
atomic_decrement32(&queue->livethreads);
}
#if defined(SDLMAME_MACOSX)
ReleaseAutoreleasePool(arp);
#endif
return NULL;
}
//============================================================
// worker_thread_process
//============================================================
static void worker_thread_process(osd_work_queue *queue, work_thread_info *thread)
{
int threadid = thread - queue->thread;
begin_timing(thread->runtime);
// loop until everything is processed
while (queue->list != NULL)
{
osd_work_item *item;
INT32 lockslot;
// use a critical section to synchronize the removal of items
lockslot = osd_scalable_lock_acquire(queue->lock);
{
// pull the item from the queue
item = (osd_work_item *)queue->list;
if (item != NULL)
{
queue->list = item->next;
if (queue->list == NULL)
queue->tailptr = (osd_work_item **)&queue->list;
}
}
osd_scalable_lock_release(queue->lock, lockslot);
// process non-NULL items
if (item != NULL)
{
// call the callback and stash the result
begin_timing(thread->actruntime);
item->result = (*item->callback)(item->param, threadid);
end_timing(thread->actruntime);
// decrement the item count after we are done
atomic_decrement32(&queue->items);
atomic_exchange32(&item->done, TRUE);
add_to_stat(&thread->itemsdone, 1);
// if it's an auto-release item, release it
if (item->flags & WORK_ITEM_FLAG_AUTO_RELEASE)
osd_work_item_release(item);
// set the result and signal the event
else if (item->event != NULL)
{
osd_event_set(item->event);
add_to_stat(&item->queue->setevents, 1);
}
// if we removed an item and there's still work to do, bump the stats
if (queue->list != NULL)
add_to_stat(&queue->extraitems, 1);
}
}
// we don't need to set the doneevent for multi queues because they spin
if (queue->waiting)
{
osd_event_set(queue->doneevent);
add_to_stat(&queue->setevents, 1);
}
end_timing(thread->runtime);
}
#endif // SDLMAME_NOASM