rocksdb/util/concurrent_task_limiter_impl.h
Peter Dillinger 84eef260de Remove TaskLimiterToken::ReleaseOnce for fix (#8567)
Summary:
Rare TSAN and valgrind failures are caused by unnecessary
reading of a field on the TaskLimiterToken::limiter_ for an assertion
after the token has been released and the limiter destroyed. To simplify
we can simply destroy the token before triggering DB shutdown
(potentially destroying the limiter). This makes the ReleaseOnce logic
unnecessary.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8567

Test Plan: watch for more failures in CI

Reviewed By: ajkr

Differential Revision: D29811795

Pulled By: pdillinger

fbshipit-source-id: 135549ebb98fe4f176d1542ed85d5bd6350a40b3
2021-07-21 17:37:53 -07:00

68 lines
2.0 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
//
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#pragma once
#include <atomic>
#include <memory>
#include "rocksdb/env.h"
#include "rocksdb/concurrent_task_limiter.h"
namespace ROCKSDB_NAMESPACE {
class TaskLimiterToken;
class ConcurrentTaskLimiterImpl : public ConcurrentTaskLimiter {
public:
explicit ConcurrentTaskLimiterImpl(const std::string& name,
int32_t max_outstanding_task);
// No copying allowed
ConcurrentTaskLimiterImpl(const ConcurrentTaskLimiterImpl&) = delete;
ConcurrentTaskLimiterImpl& operator=(const ConcurrentTaskLimiterImpl&) =
delete;
virtual ~ConcurrentTaskLimiterImpl();
virtual const std::string& GetName() const override;
virtual void SetMaxOutstandingTask(int32_t limit) override;
virtual void ResetMaxOutstandingTask() override;
virtual int32_t GetOutstandingTask() const override;
// Request token for adding a new task.
// If force == true, it requests a token bypassing throttle.
// Returns nullptr if it got throttled.
virtual std::unique_ptr<TaskLimiterToken> GetToken(bool force);
private:
friend class TaskLimiterToken;
std::string name_;
std::atomic<int32_t> max_outstanding_tasks_;
std::atomic<int32_t> outstanding_tasks_;
};
class TaskLimiterToken {
public:
explicit TaskLimiterToken(ConcurrentTaskLimiterImpl* limiter)
: limiter_(limiter) {}
~TaskLimiterToken();
private:
ConcurrentTaskLimiterImpl* limiter_;
// no copying allowed
TaskLimiterToken(const TaskLimiterToken&) = delete;
void operator=(const TaskLimiterToken&) = delete;
};
} // namespace ROCKSDB_NAMESPACE