diff options
author | RĂ©mi Verschelde <remi@verschelde.fr> | 2022-07-22 13:25:31 +0200 |
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committer | GitHub <noreply@github.com> | 2022-07-22 13:25:31 +0200 |
commit | d2fa9cbdfd43c75cd76917d2c4db26f2489d2717 (patch) | |
tree | bb6d9e828c1dfcab7ff102e388a0182702b7a35f /core/object | |
parent | 653f95282ccd31a4e38a157bb7845405079de371 (diff) | |
parent | 67a260d63f971a6dca2b8716a220831928661085 (diff) |
Merge pull request #63141 from reduz/implement-thread-runner
Diffstat (limited to 'core/object')
-rw-r--r-- | core/object/worker_thread_pool.cpp | 463 | ||||
-rw-r--r-- | core/object/worker_thread_pool.h | 146 |
2 files changed, 609 insertions, 0 deletions
diff --git a/core/object/worker_thread_pool.cpp b/core/object/worker_thread_pool.cpp new file mode 100644 index 0000000000..c276802f99 --- /dev/null +++ b/core/object/worker_thread_pool.cpp @@ -0,0 +1,463 @@ +/*************************************************************************/ +/* worker_thread_pool.cpp */ +/*************************************************************************/ +/* This file is part of: */ +/* GODOT ENGINE */ +/* https://godotengine.org */ +/*************************************************************************/ +/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur. */ +/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md). */ +/* */ +/* Permission is hereby granted, free of charge, to any person obtaining */ +/* a copy of this software and associated documentation files (the */ +/* "Software"), to deal in the Software without restriction, including */ +/* without limitation the rights to use, copy, modify, merge, publish, */ +/* distribute, sublicense, and/or sell copies of the Software, and to */ +/* permit persons to whom the Software is furnished to do so, subject to */ +/* the following conditions: */ +/* */ +/* The above copyright notice and this permission notice shall be */ +/* included in all copies or substantial portions of the Software. */ +/* */ +/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */ +/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */ +/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/ +/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */ +/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */ +/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */ +/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ +/*************************************************************************/ + +#include "worker_thread_pool.h" + +#include "core/os/os.h" + +WorkerThreadPool *WorkerThreadPool::singleton = nullptr; + +void WorkerThreadPool::_process_task_queue() { + task_mutex.lock(); + Task *task = task_queue.first()->self(); + task_queue.remove(task_queue.first()); + task_mutex.unlock(); + _process_task(task); +} + +void WorkerThreadPool::_process_task(Task *p_task) { + bool low_priority = p_task->low_priority; + + if (p_task->group) { + // Handling a group + bool do_post = false; + if (p_task->native_group_func) { + while (true) { + uint32_t work_index = p_task->group->index.postincrement(); + if (work_index >= p_task->group->max) { + do_post = work_index == p_task->group->max; // First one reaching max handles semaphore and clean-up. + break; + } + p_task->native_group_func(p_task->native_func_userdata, work_index); + } + + } else { + Callable::CallError ce; + Variant ret; + Variant arg; + Variant *argptr = &arg; + while (true) { + uint32_t work_index = p_task->group->index.postincrement(); + if (work_index >= p_task->group->max) { + do_post = work_index == p_task->group->max; // First one reaching max handles semaphore and clean-up. + break; + } + arg = work_index; + p_task->callable.call((const Variant **)&argptr, 1, ret, ce); + } + } + + if (low_priority && use_native_low_priority_threads) { + p_task->completed = true; + p_task->done_semaphore.post(); + if (do_post) { + p_task->group->completed.set_to(true); + } + } else { + if (do_post) { + p_task->group->done_semaphore.post(); + p_task->group->completed.set_to(true); + } + uint32_t max_users = p_task->group->tasks_used + 1; // Add 1 because the thread waiting for it is also user. Read before to avoid another thread freeing task after increment. + uint32_t finished_users = p_task->group->finished.increment(); + + if (finished_users == max_users) { + // Get rid of the group, because nobody else is using it. + task_mutex.lock(); + group_allocator.free(p_task->group); + task_mutex.unlock(); + } + + // For groups, tasks get rid of themselves. + + task_mutex.lock(); + task_allocator.free(p_task); + task_mutex.unlock(); + } + } else { + if (p_task->native_func) { + p_task->native_func(p_task->native_func_userdata); + } else { + Callable::CallError ce; + Variant ret; + p_task->callable.call(nullptr, 0, ret, ce); + } + + p_task->completed = true; + p_task->done_semaphore.post(); + } + + if (!use_native_low_priority_threads && low_priority) { + // A low prioriry task was freed, so see if we can move a pending one to the high priority queue. + bool post = false; + task_mutex.lock(); + if (low_priority_task_queue.first()) { + Task *low_prio_task = low_priority_task_queue.first()->self(); + low_priority_task_queue.remove(low_priority_task_queue.first()); + task_queue.add_last(&low_prio_task->task_elem); + post = true; + } else { + low_priority_threads_used.decrement(); + } + task_mutex.lock(); + if (post) { + task_available_semaphore.post(); + } + } +} + +void WorkerThreadPool::_thread_function(void *p_user) { + while (true) { + singleton->task_available_semaphore.wait(); + if (singleton->exit_threads.is_set()) { + break; + } + singleton->_process_task_queue(); + } +} + +void WorkerThreadPool::_native_low_priority_thread_function(void *p_user) { + Task *task = (Task *)p_user; + singleton->_process_task(task); +} + +void WorkerThreadPool::_post_task(Task *p_task, bool p_high_priority) { + task_mutex.lock(); + p_task->low_priority = !p_high_priority; + if (!p_high_priority && use_native_low_priority_threads) { + task_mutex.unlock(); + p_task->low_priority_thread = native_thread_allocator.alloc(); + p_task->low_priority_thread->start(_native_low_priority_thread_function, p_task); // Pask task directly to thread. + + } else if (p_high_priority || low_priority_threads_used.get() < max_low_priority_threads) { + task_queue.add_last(&p_task->task_elem); + if (!p_high_priority) { + low_priority_threads_used.increment(); + } + task_mutex.unlock(); + task_available_semaphore.post(); + } else { + // Too many threads using low priority, must go to queue. + low_priority_task_queue.add_last(&p_task->task_elem); + task_mutex.unlock(); + } +} + +WorkerThreadPool::TaskID WorkerThreadPool::add_native_task(void (*p_func)(void *), void *p_userdata, bool p_high_priority, const String &p_description) { + task_mutex.lock(); + // Get a free task + Task *task = task_allocator.alloc(); + TaskID id = last_task++; + task->native_func = p_func; + task->native_func_userdata = p_userdata; + task->description = p_description; + tasks.insert(id, task); + task_mutex.unlock(); + + _post_task(task, p_high_priority); + + return id; +} + +WorkerThreadPool::TaskID WorkerThreadPool::add_task(const Callable &p_action, bool p_high_priority, const String &p_description) { + task_mutex.lock(); + // Get a free task + Task *task = task_allocator.alloc(); + TaskID id = last_task++; + task->callable = p_action; + task->description = p_description; + tasks.insert(id, task); + task_mutex.unlock(); + + _post_task(task, p_high_priority); + + return id; +} + +bool WorkerThreadPool::is_task_completed(TaskID p_task_id) const { + task_mutex.lock(); + const Task *const *taskp = tasks.getptr(p_task_id); + if (!taskp) { + task_mutex.unlock(); + ERR_FAIL_V_MSG(false, "Invalid Task ID"); // Invalid task + } + + bool completed = (*taskp)->completed; + task_mutex.unlock(); + + return completed; +} + +void WorkerThreadPool::wait_for_task_completion(TaskID p_task_id) { + task_mutex.lock(); + Task **taskp = tasks.getptr(p_task_id); + if (!taskp) { + task_mutex.unlock(); + ERR_FAIL_MSG("Invalid Task ID"); // Invalid task + } + Task *task = *taskp; + + if (task->waiting) { + String description = task->description; + task_mutex.unlock(); + if (description.is_empty()) { + ERR_FAIL_MSG("Another thread is waiting on this task: " + itos(p_task_id)); // Invalid task + } else { + ERR_FAIL_MSG("Another thread is waiting on this task: " + description + " (" + itos(p_task_id) + ")"); // Invalid task + } + } + + task->waiting = true; + + task_mutex.unlock(); + + if (use_native_low_priority_threads && task->low_priority) { + task->low_priority_thread->wait_to_finish(); + native_thread_allocator.free(task->low_priority_thread); + } else { + int *index = thread_ids.getptr(Thread::get_caller_id()); + + if (index) { + // We are an actual process thread, we must not be blocked so continue processing stuff if available. + while (true) { + if (task->done_semaphore.try_wait()) { + // If done, exit + break; + } + if (task_available_semaphore.try_wait()) { + // Solve tasks while they are around. + _process_task_queue(); + continue; + } + OS::get_singleton()->delay_usec(1); // Microsleep, this could be converted to waiting for multiple objects in supported platforms for a bit more performance. + } + } else { + task->done_semaphore.wait(); + } + } + + task_mutex.lock(); + tasks.erase(p_task_id); + task_allocator.free(task); + task_mutex.unlock(); +} + +WorkerThreadPool::GroupID WorkerThreadPool::add_native_group_task(void (*p_func)(void *, uint32_t), void *p_userdata, int p_elements, int p_tasks, bool p_high_priority, const String &p_description) { + ERR_FAIL_COND_V(p_elements <= 0, INVALID_TASK_ID); + if (p_tasks < 0) { + p_tasks = threads.size(); + } + + task_mutex.lock(); + Group *group = group_allocator.alloc(); + GroupID id = last_task++; + group->max = p_elements; + group->self = id; + group->tasks_used = p_tasks; + Task **tasks_posted = (Task **)alloca(sizeof(Task *) * p_tasks); + for (int i = 0; i < p_tasks; i++) { + Task *task = task_allocator.alloc(); + task->native_group_func = p_func; + task->native_func_userdata = p_userdata; + task->description = p_description; + task->group = group; + tasks_posted[i] = task; + // No task ID is used. + } + groups[id] = group; + task_mutex.unlock(); + + if (!p_high_priority && use_native_low_priority_threads) { + group->low_priority_native_tasks.resize(p_tasks); + } + + for (int i = 0; i < p_tasks; i++) { + _post_task(tasks_posted[i], p_high_priority); + if (!p_high_priority && use_native_low_priority_threads) { + group->low_priority_native_tasks[i] = tasks_posted[i]; + } + } + + return id; +} + +WorkerThreadPool::GroupID WorkerThreadPool::add_group_task(const Callable &p_action, int p_elements, int p_tasks, bool p_high_priority, const String &p_description) { + ERR_FAIL_COND_V(p_elements <= 0, INVALID_TASK_ID); + if (p_tasks < 0) { + p_tasks = threads.size(); + } + + task_mutex.lock(); + Group *group = group_allocator.alloc(); + GroupID id = last_task++; + group->max = p_elements; + group->self = id; + group->tasks_used = p_tasks; + Task **tasks_posted = (Task **)alloca(sizeof(Task *) * p_tasks); + for (int i = 0; i < p_tasks; i++) { + Task *task = task_allocator.alloc(); + task->callable = p_action; + task->description = p_description; + task->group = group; + tasks_posted[i] = task; + // No task ID is used. + } + groups[id] = group; + task_mutex.unlock(); + + if (!p_high_priority && use_native_low_priority_threads) { + group->low_priority_native_tasks.resize(p_tasks); + } + + for (int i = 0; i < p_tasks; i++) { + _post_task(tasks_posted[i], p_high_priority); + if (!p_high_priority && use_native_low_priority_threads) { + group->low_priority_native_tasks[i] = tasks_posted[i]; + } + } + return id; +} + +bool WorkerThreadPool::is_group_task_completed(GroupID p_group) const { + task_mutex.lock(); + const Group *const *groupp = groups.getptr(p_group); + if (!groupp) { + task_mutex.unlock(); + ERR_FAIL_V_MSG(false, "Invalid Group ID"); + } + bool completed = (*groupp)->completed.is_set(); + task_mutex.unlock(); + return completed; +} + +void WorkerThreadPool::wait_for_group_task_completion(GroupID p_group) { + task_mutex.lock(); + Group **groupp = groups.getptr(p_group); + task_mutex.unlock(); + if (!groupp) { + ERR_FAIL_MSG("Invalid Group ID"); + } + Group *group = *groupp; + + if (group->low_priority_native_tasks.size() > 0) { + for (uint32_t i = 0; i < group->low_priority_native_tasks.size(); i++) { + group->low_priority_native_tasks[i]->low_priority_thread->wait_to_finish(); + native_thread_allocator.free(group->low_priority_native_tasks[i]->low_priority_thread); + task_mutex.lock(); + task_allocator.free(group->low_priority_native_tasks[i]); + task_mutex.unlock(); + } + + task_mutex.lock(); + group_allocator.free(group); + task_mutex.unlock(); + } else { + group->done_semaphore.wait(); + + uint32_t max_users = group->tasks_used + 1; // Add 1 because the thread waiting for it is also user. Read before to avoid another thread freeing task after increment. + uint32_t finished_users = group->finished.increment(); // fetch happens before inc, so increment later. + + if (finished_users == max_users) { + // All tasks using this group are gone (finished before the group), so clear the gorup too. + task_mutex.lock(); + group_allocator.free(group); + task_mutex.unlock(); + } + } + + groups.erase(p_group); // Threads do not access this, so safe to erase here. +} + +void WorkerThreadPool::init(int p_thread_count, bool p_use_native_threads_low_priority, float p_low_priority_task_ratio) { + ERR_FAIL_COND(threads.size() > 0); + if (p_thread_count < 0) { + p_thread_count = OS::get_singleton()->get_default_thread_pool_size(); + } + + if (p_use_native_threads_low_priority) { + max_low_priority_threads = 0; + } else { + max_low_priority_threads = CLAMP(p_thread_count * p_low_priority_task_ratio, 1, p_thread_count); + } + + use_native_low_priority_threads = p_use_native_threads_low_priority; + + threads.resize(p_thread_count); + + for (uint32_t i = 0; i < threads.size(); i++) { + threads[i].index = i; + threads[i].thread.start(&WorkerThreadPool::_thread_function, &threads[i]); + thread_ids.insert(threads[i].thread.get_id(), i); + } +} + +void WorkerThreadPool::finish() { + if (threads.size() == 0) { + return; + } + + task_mutex.lock(); + SelfList<Task> *E = low_priority_task_queue.first(); + while (E) { + print_error("Task waiting was never re-claimed: " + E->self()->description); + E = E->next(); + } + task_mutex.unlock(); + + exit_threads.set_to(true); + + for (uint32_t i = 0; i < threads.size(); i++) { + task_available_semaphore.post(); + } + + for (uint32_t i = 0; i < threads.size(); i++) { + threads[i].thread.wait_to_finish(); + } + + threads.clear(); +} + +void WorkerThreadPool::_bind_methods() { + ClassDB::bind_method(D_METHOD("add_task", "action", "high_priority", "description"), &WorkerThreadPool::add_task, DEFVAL(false), DEFVAL(String())); + ClassDB::bind_method(D_METHOD("is_task_completed", "task_id"), &WorkerThreadPool::is_task_completed); + ClassDB::bind_method(D_METHOD("wait_for_task_completion", "task_id"), &WorkerThreadPool::wait_for_task_completion); + + ClassDB::bind_method(D_METHOD("add_group_task", "action", "elements", "tasks_needed", "high_priority", "description"), &WorkerThreadPool::add_group_task, DEFVAL(-1), DEFVAL(false), DEFVAL(String())); + ClassDB::bind_method(D_METHOD("is_group_task_completed", "group_id"), &WorkerThreadPool::is_group_task_completed); + ClassDB::bind_method(D_METHOD("wait_for_group_task_completion", "group_id"), &WorkerThreadPool::wait_for_group_task_completion); +} + +WorkerThreadPool::WorkerThreadPool() { + singleton = this; +} + +WorkerThreadPool::~WorkerThreadPool() { + finish(); +} diff --git a/core/object/worker_thread_pool.h b/core/object/worker_thread_pool.h new file mode 100644 index 0000000000..dfb0050605 --- /dev/null +++ b/core/object/worker_thread_pool.h @@ -0,0 +1,146 @@ +/*************************************************************************/ +/* worker_thread_pool.h */ +/*************************************************************************/ +/* This file is part of: */ +/* GODOT ENGINE */ +/* https://godotengine.org */ +/*************************************************************************/ +/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur. */ +/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md). */ +/* */ +/* Permission is hereby granted, free of charge, to any person obtaining */ +/* a copy of this software and associated documentation files (the */ +/* "Software"), to deal in the Software without restriction, including */ +/* without limitation the rights to use, copy, modify, merge, publish, */ +/* distribute, sublicense, and/or sell copies of the Software, and to */ +/* permit persons to whom the Software is furnished to do so, subject to */ +/* the following conditions: */ +/* */ +/* The above copyright notice and this permission notice shall be */ +/* included in all copies or substantial portions of the Software. */ +/* */ +/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */ +/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */ +/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/ +/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */ +/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */ +/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */ +/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ +/*************************************************************************/ + +#ifndef WORKER_THREAD_POOL_H +#define WORKER_THREAD_POOL_H + +#include "core/os/memory.h" +#include "core/os/os.h" +#include "core/os/semaphore.h" +#include "core/os/thread.h" +#include "core/templates/local_vector.h" +#include "core/templates/paged_allocator.h" +#include "core/templates/rid.h" +#include "core/templates/safe_refcount.h" + +class WorkerThreadPool : public Object { + GDCLASS(WorkerThreadPool, Object) +public: + enum { + INVALID_TASK_ID = -1 + }; + + typedef int64_t TaskID; + typedef int64_t GroupID; + +private: + struct Task; + + struct Group { + GroupID self; + SafeNumeric<uint32_t> index; + uint32_t max = 0; + Semaphore done_semaphore; + SafeFlag completed; + SafeNumeric<uint32_t> finished; + uint32_t tasks_used = 0; + TightLocalVector<Task *> low_priority_native_tasks; + }; + + struct Task { + Callable callable; + void (*native_func)(void *) = nullptr; + void (*native_group_func)(void *, uint32_t) = nullptr; + void *native_func_userdata = nullptr; + String description; + Semaphore done_semaphore; + bool completed = false; + Group *group = nullptr; + SelfList<Task> task_elem; + bool waiting = false; // Waiting for completion + bool low_priority = false; + Thread *low_priority_thread = nullptr; + Task() : + task_elem(this) {} + }; + + PagedAllocator<Task> task_allocator; + PagedAllocator<Group> group_allocator; + PagedAllocator<Thread> native_thread_allocator; + + SelfList<Task>::List low_priority_task_queue; + SelfList<Task>::List task_queue; + + Mutex task_mutex; + Semaphore task_available_semaphore; + + struct ThreadData { + uint32_t index; + Thread thread; + }; + + TightLocalVector<ThreadData> threads; + SafeFlag exit_threads; + + HashMap<Thread::ID, int> thread_ids; + HashMap<TaskID, Task *> tasks; + HashMap<GroupID, Group *> groups; + + bool use_native_low_priority_threads = false; + uint32_t max_low_priority_threads = 0; + SafeNumeric<uint32_t> low_priority_threads_used; + + uint64_t last_task = 1; + + static void _thread_function(void *p_user); + static void _native_low_priority_thread_function(void *p_user); + + void _process_task_queue(); + void _process_task(Task *task); + + void _post_task(Task *p_task, bool p_high_priority); + + static WorkerThreadPool *singleton; + +protected: + static void _bind_methods(); + +public: + TaskID add_native_task(void (*p_func)(void *), void *p_userdata, bool p_high_priority = false, const String &p_description = String()); + TaskID add_task(const Callable &p_action, bool p_high_priority = false, const String &p_description = String()); + + bool is_task_completed(TaskID p_task_id) const; + void wait_for_task_completion(TaskID p_task_id); + + GroupID add_native_group_task(void (*p_func)(void *, uint32_t), void *p_userdata, int p_elements, int p_tasks = -1, bool p_high_priority = false, const String &p_description = String()); + GroupID add_group_task(const Callable &p_action, int p_elements, int p_tasks = -1, bool p_high_priority = false, const String &p_description = String()); + bool is_group_task_completed(GroupID p_group) const; + void wait_for_group_task_completion(GroupID p_group); + + _FORCE_INLINE_ int get_thread_count() const { return threads.size(); } + + static WorkerThreadPool *get_singleton() { return singleton; } + void init(int p_thread_count = -1, bool p_use_native_threads_low_priority = true, float p_low_priority_task_ratio = 0.3); + void finish(); + WorkerThreadPool(); + ~WorkerThreadPool(); +}; + +#endif // WORKER_THREAD_POOL_H |