void mpmcq_push(mpmcq_t* q, void* data)
{
mpmcq_node_t* node = POOL_ALLOC(mpmcq_node_t);
node->data = data;
node->next = NULL;
mpmcq_node_t* prev = (mpmcq_node_t*)_atomic_exchange(&q->head, node);
_atomic_store(&prev->next, node);
}
bool ponyint_messageq_push(messageq_t* q, pony_msg_t* m)
{
m->next = NULL;
pony_msg_t* prev = (pony_msg_t*)_atomic_exchange(&q->head, m);
bool was_empty = ((uintptr_t)prev & 1) != 0;
prev = (pony_msg_t*)((uintptr_t)prev & ~(uintptr_t)1);
_atomic_store(&prev->next, m);
return was_empty;
}
static void
_freed_pool_put (freed_pool_t *pool, void *ptr)
{
int i = pool->top;
if (_atomic_store (&pool->pool[i], ptr)) {
pool->top = i + 1;
return;
}
/* either full or contended */
for (i = 0; i < ARRAY_LENGTH (pool->pool); i++) {
if (_atomic_store (&pool->pool[i], ptr)) {
pool->top = i + 1;
return;
}
}
/* full */
pool->top = ARRAY_LENGTH (pool->pool);
free (ptr);
}
void
_freed_pool_put_search (freed_pool_t *pool, void *ptr)
{
int i;
for (i = 0; i < ARRAY_LENGTH (pool->pool); i++) {
if (_atomic_store (&pool->pool[i], ptr)) {
_cairo_atomic_int_set_relaxed (&pool->top, i + 1);
return;
}
}
/* full */
_cairo_atomic_int_set_relaxed (&pool->top, i);
free (ptr);
}
void* ponyint_mpmcq_pop(mpmcq_t* q)
{
mpmcq_dwcas_t cmp, xchg;
mpmcq_node_t* next;
cmp.aba = q->tail.aba;
cmp.node = q->tail.node;
do
{
// Get the next node rather than the tail. The tail is either a stub or has
// already been consumed.
next = _atomic_load(&cmp.node->next);
// Bailout if we have no next node.
if(next == NULL)
return NULL;
// Make the next node the tail, incrementing the aba counter. If this
// fails, cmp becomes the new tail and we retry the loop.
xchg.aba = cmp.aba + 1;
xchg.node = next;
} while(!_atomic_dwcas(&q->tail.dw, &cmp.dw, xchg.dw));
// We'll return the data pointer from the next node.
void* data = _atomic_load(&next->data);
// Since we will be freeing the old tail, we need to be sure no other
// consumer is still reading the old tail. To do this, we set the data
// pointer of our new tail to NULL, and we wait until the data pointer of
// the old tail is NULL.
_atomic_store(&next->data, NULL);
while(_atomic_load(&cmp.node->data) != NULL)
ponyint_cpu_relax();
// Free the old tail. The new tail is the next node.
POOL_FREE(mpmcq_node_t, cmp.node);
return data;
}
void pony_exitcode(int code)
{
_atomic_store(&exit_code, code);
}
void pony_exitcode(int code)
{
_atomic_store(&exit_code, code, __ATOMIC_RELEASE);
}
