citra-shitamoto-network/src/common/thread_queue_list.h
2014-12-20 21:20:24 -08:00

217 lines
5.9 KiB
C++

// Copyright 2014 Citra Emulator Project / PPSSPP Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#pragma once
#include "common/common.h"
namespace Common {
template<class IdType>
struct ThreadQueueList {
// Number of queues (number of priority levels starting at 0.)
static const int NUM_QUEUES = 128;
// Initial number of threads a single queue can handle.
static const int INITIAL_CAPACITY = 32;
struct Queue {
// Next ever-been-used queue (worse priority.)
Queue *next;
// First valid item in data.
int first;
// One after last valid item in data.
int end;
// A too-large array with room on the front and end.
IdType *data;
// Size of data array.
int capacity;
};
ThreadQueueList() {
memset(queues, 0, sizeof(queues));
first = invalid();
}
~ThreadQueueList() {
for (int i = 0; i < NUM_QUEUES; ++i)
{
if (queues[i].data != nullptr)
free(queues[i].data);
}
}
// Only for debugging, returns priority level.
int contains(const IdType uid) {
for (int i = 0; i < NUM_QUEUES; ++i)
{
if (queues[i].data == nullptr)
continue;
Queue *cur = &queues[i];
for (int j = cur->first; j < cur->end; ++j)
{
if (cur->data[j] == uid)
return i;
}
}
return -1;
}
inline IdType pop_first() {
Queue *cur = first;
while (cur != invalid())
{
if (cur->end - cur->first > 0)
return cur->data[cur->first++];
cur = cur->next;
}
//_dbg_assert_msg_(SCEKERNEL, false, "ThreadQueueList should not be empty.");
return 0;
}
inline IdType pop_first_better(u32 priority) {
Queue *cur = first;
Queue *stop = &queues[priority];
while (cur < stop)
{
if (cur->end - cur->first > 0)
return cur->data[cur->first++];
cur = cur->next;
}
return 0;
}
inline void push_front(u32 priority, const IdType threadID) {
Queue *cur = &queues[priority];
cur->data[--cur->first] = threadID;
if (cur->first == 0)
rebalance(priority);
}
inline void push_back(u32 priority, const IdType threadID) {
Queue *cur = &queues[priority];
cur->data[cur->end++] = threadID;
if (cur->end == cur->capacity)
rebalance(priority);
}
inline void remove(u32 priority, const IdType threadID) {
Queue *cur = &queues[priority];
//_dbg_assert_msg_(SCEKERNEL, cur->next != NULL, "ThreadQueueList::Queue should already be linked up.");
for (int i = cur->first; i < cur->end; ++i)
{
if (cur->data[i] == threadID)
{
int remaining = --cur->end - i;
if (remaining > 0)
memmove(&cur->data[i], &cur->data[i + 1], remaining * sizeof(IdType));
return;
}
}
// Wasn't there.
}
inline void rotate(u32 priority) {
Queue *cur = &queues[priority];
//_dbg_assert_msg_(SCEKERNEL, cur->next != NULL, "ThreadQueueList::Queue should already be linked up.");
if (cur->end - cur->first > 1)
{
cur->data[cur->end++] = cur->data[cur->first++];
if (cur->end == cur->capacity)
rebalance(priority);
}
}
inline void clear() {
for (int i = 0; i < NUM_QUEUES; ++i)
{
if (queues[i].data != nullptr)
free(queues[i].data);
}
memset(queues, 0, sizeof(queues));
first = invalid();
}
inline bool empty(u32 priority) const {
const Queue *cur = &queues[priority];
return cur->first == cur->end;
}
inline void prepare(u32 priority) {
Queue *cur = &queues[priority];
if (cur->next == nullptr)
link(priority, INITIAL_CAPACITY);
}
private:
Queue *invalid() const {
return (Queue *) -1;
}
void link(u32 priority, int size) {
//_dbg_assert_msg_(SCEKERNEL, queues[priority].data == NULL, "ThreadQueueList::Queue should only be initialized once.");
if (size <= INITIAL_CAPACITY)
size = INITIAL_CAPACITY;
else
{
int goal = size;
size = INITIAL_CAPACITY;
while (size < goal)
size *= 2;
}
Queue *cur = &queues[priority];
cur->data = (IdType *) malloc(sizeof(IdType) * size);
cur->capacity = size;
cur->first = size / 2;
cur->end = size / 2;
for (int i = (int) priority - 1; i >= 0; --i)
{
if (queues[i].next != nullptr)
{
cur->next = queues[i].next;
queues[i].next = cur;
return;
}
}
cur->next = first;
first = cur;
}
void rebalance(u32 priority) {
Queue *cur = &queues[priority];
int size = cur->end - cur->first;
if (size >= cur->capacity - 2) {
IdType *new_data = (IdType *)realloc(cur->data, cur->capacity * 2 * sizeof(IdType));
if (new_data != nullptr) {
cur->capacity *= 2;
cur->data = new_data;
}
}
int newFirst = (cur->capacity - size) / 2;
if (newFirst != cur->first) {
memmove(&cur->data[newFirst], &cur->data[cur->first], size * sizeof(IdType));
cur->first = newFirst;
cur->end = newFirst + size;
}
}
// The first queue that's ever been used.
Queue *first;
// The priority level queues of thread ids.
Queue queues[NUM_QUEUES];
};
} // namespace