146 lines
4.4 KiB
C++
146 lines
4.4 KiB
C++
// Copyright 2019 The MediaPipe Authors.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
// Consider this file an implementation detail. None of this is part of the
|
|
// public API.
|
|
|
|
#ifndef MEDIAPIPE_GPU_REUSABLE_POOL_H_
|
|
#define MEDIAPIPE_GPU_REUSABLE_POOL_H_
|
|
|
|
#include <utility>
|
|
#include <vector>
|
|
|
|
#include "absl/functional/any_invocable.h"
|
|
#include "absl/synchronization/mutex.h"
|
|
#include "mediapipe/gpu/multi_pool.h"
|
|
|
|
namespace mediapipe {
|
|
|
|
template <class Item>
|
|
class ReusablePool : public std::enable_shared_from_this<ReusablePool<Item>> {
|
|
public:
|
|
using ItemFactory = absl::AnyInvocable<std::unique_ptr<Item>() const>;
|
|
|
|
// Creates a pool. This pool will manage buffers of the specified dimensions,
|
|
// and will keep keep_count buffers around for reuse.
|
|
// We enforce creation as a shared_ptr so that we can use a weak reference in
|
|
// the buffers' deleters.
|
|
static std::shared_ptr<ReusablePool<Item>> Create(
|
|
ItemFactory item_factory, const MultiPoolOptions& options) {
|
|
return std::shared_ptr<ReusablePool<Item>>(
|
|
new ReusablePool<Item>(std::move(item_factory), options));
|
|
}
|
|
|
|
// Obtains a buffer. May either be reused or created anew.
|
|
// A GlContext must be current when this is called.
|
|
std::shared_ptr<Item> GetBuffer();
|
|
|
|
// This method is meant for testing.
|
|
std::pair<int, int> GetInUseAndAvailableCounts();
|
|
|
|
protected:
|
|
ReusablePool(ItemFactory item_factory, const MultiPoolOptions& options)
|
|
: item_factory_(std::move(item_factory)),
|
|
keep_count_(options.keep_count) {}
|
|
|
|
private:
|
|
// Return a buffer to the pool.
|
|
void Return(std::unique_ptr<Item> buf);
|
|
|
|
// If the total number of buffers is greater than keep_count, destroys any
|
|
// surplus buffers that are no longer in use.
|
|
void TrimAvailable(std::vector<std::unique_ptr<Item>>* trimmed)
|
|
ABSL_EXCLUSIVE_LOCKS_REQUIRED(mutex_);
|
|
|
|
const ItemFactory item_factory_;
|
|
const int keep_count_;
|
|
|
|
absl::Mutex mutex_;
|
|
int in_use_count_ ABSL_GUARDED_BY(mutex_) = 0;
|
|
std::vector<std::unique_ptr<Item>> available_ ABSL_GUARDED_BY(mutex_);
|
|
};
|
|
|
|
template <class Item>
|
|
inline std::shared_ptr<Item> ReusablePool<Item>::GetBuffer() {
|
|
std::unique_ptr<Item> buffer;
|
|
bool reuse = false;
|
|
|
|
{
|
|
absl::MutexLock lock(&mutex_);
|
|
if (available_.empty()) {
|
|
buffer = item_factory_();
|
|
if (!buffer) return nullptr;
|
|
} else {
|
|
buffer = std::move(available_.back());
|
|
available_.pop_back();
|
|
reuse = true;
|
|
}
|
|
|
|
++in_use_count_;
|
|
}
|
|
|
|
// This needs to wait on consumer sync points, therefore it should not be
|
|
// done while holding the mutex.
|
|
if (reuse) {
|
|
buffer->Reuse();
|
|
}
|
|
|
|
// Return a shared_ptr with a custom deleter that adds the buffer back
|
|
// to our available list.
|
|
std::weak_ptr<ReusablePool<Item>> weak_pool(this->shared_from_this());
|
|
return std::shared_ptr<Item>(buffer.release(), [weak_pool](Item* buf) {
|
|
auto pool = weak_pool.lock();
|
|
if (pool) {
|
|
pool->Return(absl::WrapUnique(buf));
|
|
} else {
|
|
delete buf;
|
|
}
|
|
});
|
|
}
|
|
|
|
template <class Item>
|
|
inline std::pair<int, int> ReusablePool<Item>::GetInUseAndAvailableCounts() {
|
|
absl::MutexLock lock(&mutex_);
|
|
return {in_use_count_, available_.size()};
|
|
}
|
|
|
|
template <class Item>
|
|
void ReusablePool<Item>::Return(std::unique_ptr<Item> buf) {
|
|
std::vector<std::unique_ptr<Item>> trimmed;
|
|
{
|
|
absl::MutexLock lock(&mutex_);
|
|
--in_use_count_;
|
|
available_.emplace_back(std::move(buf));
|
|
TrimAvailable(&trimmed);
|
|
}
|
|
// The trimmed buffers will be released without holding the lock.
|
|
}
|
|
|
|
template <class Item>
|
|
void ReusablePool<Item>::TrimAvailable(
|
|
std::vector<std::unique_ptr<Item>>* trimmed) {
|
|
int keep = std::max(keep_count_ - in_use_count_, 0);
|
|
if (available_.size() > keep) {
|
|
auto trim_it = std::next(available_.begin(), keep);
|
|
if (trimmed) {
|
|
std::move(trim_it, available_.end(), std::back_inserter(*trimmed));
|
|
}
|
|
available_.erase(trim_it, available_.end());
|
|
}
|
|
}
|
|
|
|
} // namespace mediapipe
|
|
|
|
#endif // MEDIAPIPE_GPU_REUSABLE_POOL_H_
|