Merge pull request #72784 from myaaaaaaaaa/parallel-foreach

Implement parallel `foreach()` for easier multithreading
This commit is contained in:
Yuri Sizov 2023-07-14 18:48:49 +02:00
commit 2a595c26d9
4 changed files with 50 additions and 40 deletions

View File

@ -202,4 +202,25 @@ public:
~WorkerThreadPool();
};
template <typename F>
static _FORCE_INLINE_ void for_range(int i_begin, int i_end, bool parallel, String name, F f) {
if (!parallel) {
for (int i = i_begin; i < i_end; i++) {
f(i);
}
return;
}
auto wrapper = [&](int i, void *unused) {
f(i + i_begin);
};
WorkerThreadPool *wtp = WorkerThreadPool::get_singleton();
WorkerThreadPool::GroupID gid = wtp->add_template_group_task(
&wrapper, &decltype(wrapper)::operator(), nullptr,
i_end - i_begin, -1,
true, name);
wtp->wait_for_group_task_completion(gid);
}
#endif // WORKER_THREAD_POOL_H

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@ -355,41 +355,14 @@ void RaycastOcclusionCull::Scenario::_update_dirty_instance(int p_idx, RID *p_in
// Embree requires the last element to be readable by a 16-byte SSE load instruction, so we add padding to be safe.
occ_inst->xformed_vertices.resize(vertices_size + 1);
const Vector3 *read_ptr = occ->vertices.ptr();
Vector3 *write_ptr = occ_inst->xformed_vertices.ptr();
if (vertices_size > 1024) {
TransformThreadData td;
td.xform = occ_inst->xform;
td.read = read_ptr;
td.write = write_ptr;
td.vertex_count = vertices_size;
td.thread_count = WorkerThreadPool::get_singleton()->get_thread_count();
WorkerThreadPool::GroupID group_task = WorkerThreadPool::get_singleton()->add_template_group_task(this, &Scenario::_transform_vertices_thread, &td, td.thread_count, -1, true, SNAME("RaycastOcclusionCull"));
WorkerThreadPool::get_singleton()->wait_for_group_task_completion(group_task);
} else {
_transform_vertices_range(read_ptr, write_ptr, occ_inst->xform, 0, vertices_size);
}
for_range(0, vertices_size, vertices_size > 1024, SNAME("RaycastOcclusionCull"), [&](const int i) {
occ_inst->xformed_vertices[i] = occ_inst->xform.xform(occ->vertices[i]);
});
occ_inst->indices.resize(occ->indices.size());
memcpy(occ_inst->indices.ptr(), occ->indices.ptr(), occ->indices.size() * sizeof(int32_t));
}
void RaycastOcclusionCull::Scenario::_transform_vertices_thread(uint32_t p_thread, TransformThreadData *p_data) {
uint32_t vertex_total = p_data->vertex_count;
uint32_t total_threads = p_data->thread_count;
uint32_t from = p_thread * vertex_total / total_threads;
uint32_t to = (p_thread + 1 == total_threads) ? vertex_total : ((p_thread + 1) * vertex_total / total_threads);
_transform_vertices_range(p_data->read, p_data->write, p_data->xform, from, to);
}
void RaycastOcclusionCull::Scenario::_transform_vertices_range(const Vector3 *p_read, Vector3 *p_write, const Transform3D &p_xform, int p_from, int p_to) {
for (int i = p_from; i < p_to; i++) {
p_write[i] = p_xform.xform(p_read[i]);
}
}
void RaycastOcclusionCull::Scenario::_commit_scene(void *p_ud) {
Scenario *scenario = (Scenario *)p_ud;
int commit_idx = 1 - (scenario->current_scene_idx);

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@ -121,14 +121,6 @@ private:
const uint32_t *masks;
};
struct TransformThreadData {
uint32_t thread_count;
uint32_t vertex_count;
Transform3D xform;
const Vector3 *read;
Vector3 *write = nullptr;
};
Thread *commit_thread = nullptr;
bool commit_done = true;
bool dirty = false;
@ -144,8 +136,6 @@ private:
void _update_dirty_instance_thread(int p_idx, RID *p_instances);
void _update_dirty_instance(int p_idx, RID *p_instances);
void _transform_vertices_thread(uint32_t p_thread, TransformThreadData *p_data);
void _transform_vertices_range(const Vector3 *p_read, Vector3 *p_write, const Transform3D &p_xform, int p_from, int p_to);
static void _commit_scene(void *p_ud);
bool update();

View File

@ -106,6 +106,32 @@ TEST_CASE("[WorkerThreadPool] Process elements using group tasks") {
}
}
TEST_CASE("[WorkerThreadPool] Parallel foreach") {
const int count_max = 256;
for (int midpoint = 0; midpoint < count_max; midpoint++) {
LocalVector<int> c;
c.resize(count_max);
for_range(0, count_max, true, String(), [&](int i) {
c[i] = 1;
});
c.sort();
CHECK(c[0] == 1);
CHECK(c[0] == c[count_max - 1]);
for_range(0, midpoint, false, String(), [&](int i) {
c[i]++;
});
for_range(midpoint, count_max, true, String(), [&](int i) {
c[i]++;
});
c.sort();
CHECK(c[0] == 2);
CHECK(c[0] == c[count_max - 1]);
}
}
} // namespace TestWorkerThreadPool
#endif // TEST_WORKER_THREAD_POOL_H