chromium/third_party/abseil-cpp/absl/profiling/internal/sample_recorder.h

// Copyright 2018 The Abseil 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
//
//      https://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.
//
// -----------------------------------------------------------------------------
// File: sample_recorder.h
// -----------------------------------------------------------------------------
//
// This header file defines a lock-free linked list for recording samples
// collected from a random/stochastic process.
//
// This utility is internal-only. Use at your own risk.

#ifndef ABSL_PROFILING_INTERNAL_SAMPLE_RECORDER_H_
#define ABSL_PROFILING_INTERNAL_SAMPLE_RECORDER_H_

#include <atomic>
#include <cstddef>
#include <functional>

#include "absl/base/config.h"
#include "absl/base/thread_annotations.h"
#include "absl/synchronization/mutex.h"
#include "absl/time/time.h"

namespace absl {
ABSL_NAMESPACE_BEGIN
namespace profiling_internal {

// Sample<T> that has members required for linking samples in the linked list of
// samples maintained by the SampleRecorder.  Type T defines the sampled data.
template <typename T>
struct Sample { … };

// Holds samples and their associated stack traces with a soft limit of
// `SetHashtablezMaxSamples()`.
//
// Thread safe.
template <typename T>
class SampleRecorder { … };

template <typename T>
typename SampleRecorder<T>::DisposeCallback
SampleRecorder<T>::SetDisposeCallback(DisposeCallback f) { … }

template <typename T>
SampleRecorder<T>::SampleRecorder()
    : … { … }

template <typename T>
SampleRecorder<T>::~SampleRecorder() { … }

template <typename T>
void SampleRecorder<T>::PushNew(T* sample) { … }

template <typename T>
void SampleRecorder<T>::PushDead(T* sample) { … }

template <typename T>
template <typename... Targs>
T* SampleRecorder<T>::PopDead(Targs... args) { … }

template <typename T>
template <typename... Targs>
T* SampleRecorder<T>::Register(Targs&&... args) { … }

template <typename T>
void SampleRecorder<T>::Unregister(T* sample) { … }

template <typename T>
int64_t SampleRecorder<T>::Iterate(
    const std::function<void(const T& stack)>& f) { … }

template <typename T>
void SampleRecorder<T>::SetMaxSamples(size_t max) { … }

template <typename T>
size_t SampleRecorder<T>::GetMaxSamples() const { … }

}  // namespace profiling_internal
ABSL_NAMESPACE_END
}  // namespace absl

#endif  // ABSL_PROFILING_INTERNAL_SAMPLE_RECORDER_H_