mirrors/Odin
1
0
Fork 0
mirror of https://github.com/odin-lang/Odin.git synced 2025-12-30 18:02:02 +00:00
Code Issues Packages Projects Releases Wiki Activity

Rewrite thread_pool.cpp

Browse Source
This commit is contained in:
nakst
2021-08-22 21:13:41 +01:00
parent 2e921c88fb
commit 1f25f60a68
3 changed files with 73 additions and 142 deletions
Download Patch File Download Diff File Expand all files Collapse all files

209
src/thread_pool.cpp
View File

@@ -1,168 +1,101 @@
// worker_queue.cpp
// thread_pool.cpp
#define WORKER_TASK_PROC(name) isize name(void *data)
typedef WORKER_TASK_PROC(WorkerTaskProc);
#if defined(GB_SYSTEM_WINDOWS)
#define THREAD_POOL_SYNC_FETCH_AND_ADD InterlockedAdd
#else
#define THREAD_POOL_SYNC_FETCH_AND_ADD __sync_fetch_and_add
#endif
struct WorkerTask {
WorkerTask *next_task;
WorkerTaskProc *do_work;
void *data;
isize result;
};
struct ThreadPool {
BlockingMutex mutex;
Semaphore sem_available;
std::atomic<i32> processing_work_count;
std::atomic<bool> is_running;
gbAllocator allocator;
MPMCQueue<WorkerTask> tasks;
Thread *threads;
isize thread_count;
char worker_prefix[10];
i32 worker_prefix_len;
volatile i32 outstanding_task_count;
WorkerTask *next_task;
BlockingMutex task_list_mutex;
};
void thread_pool_init(ThreadPool *pool, gbAllocator const &a, isize thread_count, char const *worker_prefix = nullptr);
void thread_pool_destroy(ThreadPool *pool);
void thread_pool_start(ThreadPool *pool);
void thread_pool_join(ThreadPool *pool);
void thread_pool_wait(ThreadPool *pool);
void thread_pool_add_task(ThreadPool *pool, WorkerTaskProc *proc, void *data);
THREAD_PROC(worker_thread_internal);
void worker_thread_internal();
void thread_pool_thread_entry(ThreadPool *pool) {
while (pool->outstanding_task_count) {
mutex_lock(&pool->task_list_mutex);
if (pool->next_task) {
WorkerTask *task = pool->next_task;
pool->next_task = task->next_task;
mutex_unlock(&pool->task_list_mutex);
task->do_work(task->data);
THREAD_POOL_SYNC_FETCH_AND_ADD(&pool->outstanding_task_count, -1);
free(task);
} else {
mutex_unlock(&pool->task_list_mutex);
yield();
}
}
}
#if defined(GB_SYSTEM_WINDOWS)
DWORD __stdcall thread_pool_thread_entry_platform(void *arg) {
thread_pool_thread_entry((ThreadPool *) arg);
return 0;
}
void thread_pool_start_thread(ThreadPool *pool) {
CloseHandle(CreateThread(NULL, 0, thread_pool_thread_entry_platform, pool, 0, NULL));
}
#else
void *thread_pool_thread_entry_platform(void *arg) {
thread_pool_thread_entry((ThreadPool *) arg);
return NULL;
}
void thread_pool_start_thread(ThreadPool *pool) {
pthread_t handle;
pthread_create(&handle, NULL, thread_pool_thread_entry_platform, pool);
pthread_detach(handle);
}
#endif
void thread_pool_init(ThreadPool *pool, gbAllocator const &a, isize thread_count, char const *worker_prefix) {
pool->allocator = a;
mpmc_init(&pool->tasks, a, 1024);
pool->thread_count = gb_max(thread_count, 0);
pool->threads = gb_alloc_array(a, Thread, pool->thread_count);
mutex_init(&pool->mutex);
semaphore_init(&pool->sem_available);
pool->is_running = true;
memset(pool, 0, sizeof(ThreadPool));
mutex_init(&pool->task_list_mutex);
pool->outstanding_task_count = 1;
pool->worker_prefix_len = 0;
if (worker_prefix) {
i32 worker_prefix_len = cast(i32)gb_strlen(worker_prefix);
worker_prefix_len = gb_min(worker_prefix_len, 10);
gb_memmove(pool->worker_prefix, worker_prefix, worker_prefix_len);
pool->worker_prefix_len = worker_prefix_len;
}
for (isize i = 0; i < pool->thread_count; i++) {
Thread *t = &pool->threads[i];
thread_init(t);
t->user_index = i;
#if 0
// TODO(bill): Fix this on Linux as it causes a seg-fault
if (pool->worker_prefix_len > 0) {
char worker_name[16] = {};
gb_snprintf(worker_name, gb_size_of(worker_name), "%.*s%u", pool->worker_prefix_len, pool->worker_prefix, cast(u16)i);
thread_set_name(t, worker_name);
}
#endif
for (int i = 0; i < thread_count; i++) {
thread_pool_start_thread(pool);
}
}
void thread_pool_start(ThreadPool *pool) {
for (isize i = 0; i < pool->thread_count; i++) {
Thread *t = &pool->threads[i];
thread_start(t, worker_thread_internal, pool);
}
}
void thread_pool_join(ThreadPool *pool) {
pool->is_running.store(false);
semaphore_post(&pool->sem_available, cast(i32)pool->thread_count);
yield();
for (isize i = 0; i < pool->thread_count; i++) {
Thread *t = &pool->threads[i];
thread_join(t);
}
}
void thread_pool_destroy(ThreadPool *pool) {
thread_pool_join(pool);
semaphore_destroy(&pool->sem_available);
mutex_destroy(&pool->mutex);
gb_free(pool->allocator, pool->threads);
pool->thread_count = 0;
mpmc_destroy(&pool->tasks);
mutex_destroy(&pool->task_list_mutex);
}
void thread_pool_wait(ThreadPool *pool) {
THREAD_POOL_SYNC_FETCH_AND_ADD(&pool->outstanding_task_count, -1);
void thread_pool_add_task(ThreadPool *pool, WorkerTaskProc *proc, void *data) {
mutex_lock(&pool->mutex);
WorkerTask task = {};
task.do_work = proc;
task.data = data;
mpmc_enqueue(&pool->tasks, task);
semaphore_post(&pool->sem_available, 1);
mutex_unlock(&pool->mutex);
}
bool thread_pool_try_and_pop_task(ThreadPool *pool, WorkerTask *task) {
bool got_task = false;
if (mpmc_dequeue(&pool->tasks, task)) {
pool->processing_work_count.fetch_add(1);
got_task = true;
}
return got_task;
}
void thread_pool_do_work(ThreadPool *pool, WorkerTask *task) {
task->result = task->do_work(task->data);
pool->processing_work_count.fetch_sub(1);
}
void thread_pool_wait_to_process(ThreadPool *pool) {
if (pool->thread_count == 0) {
WorkerTask task = {};
while (thread_pool_try_and_pop_task(pool, &task)) {
thread_pool_do_work(pool, &task);
}
return;
}
while (pool->tasks.count.load(std::memory_order_relaxed) > 0 || pool->processing_work_count.load() != 0) {
WorkerTask task = {};
if (thread_pool_try_and_pop_task(pool, &task)) {
thread_pool_do_work(pool, &task);
}
// Safety-kick
while (pool->tasks.count.load(std::memory_order_relaxed) > 0 && pool->processing_work_count.load() == 0) {
mutex_lock(&pool->mutex);
semaphore_post(&pool->sem_available, cast(i32)pool->tasks.count.load(std::memory_order_relaxed));
mutex_unlock(&pool->mutex);
}
while (pool->outstanding_task_count) {
yield();
}
thread_pool_join(pool);
}
THREAD_PROC(worker_thread_internal) {
ThreadPool *pool = cast(ThreadPool *)thread->user_data;
while (pool->is_running.load()) {
semaphore_wait(&pool->sem_available);
WorkerTask task = {};
if (thread_pool_try_and_pop_task(pool, &task)) {
thread_pool_do_work(pool, &task);
}
}
// Cascade
semaphore_release(&pool->sem_available);
return 0;
void thread_pool_add_task(ThreadPool *pool, WorkerTaskProc *proc, void *data) {
WorkerTask *task = (WorkerTask *) calloc(1, sizeof(WorkerTask));
task->do_work = proc;
task->data = data;
mutex_lock(&pool->task_list_mutex);
task->next_task = pool->next_task;
pool->next_task = task;
THREAD_POOL_SYNC_FETCH_AND_ADD(&pool->outstanding_task_count, 1);
mutex_unlock(&pool->task_list_mutex);
}