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Diffstat (limited to '')
-rw-r--r-- | storage/rocksdb/rocksdb/util/concurrent_task_limiter_impl.cc | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/storage/rocksdb/rocksdb/util/concurrent_task_limiter_impl.cc b/storage/rocksdb/rocksdb/util/concurrent_task_limiter_impl.cc new file mode 100644 index 00000000..2342677d --- /dev/null +++ b/storage/rocksdb/rocksdb/util/concurrent_task_limiter_impl.cc @@ -0,0 +1,67 @@ +// 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. + +#include "util/concurrent_task_limiter_impl.h" +#include "rocksdb/concurrent_task_limiter.h" + +namespace ROCKSDB_NAMESPACE { + +ConcurrentTaskLimiterImpl::ConcurrentTaskLimiterImpl( + const std::string& name, int32_t max_outstanding_task) + : name_(name), + max_outstanding_tasks_{max_outstanding_task}, + outstanding_tasks_{0} { + +} + +ConcurrentTaskLimiterImpl::~ConcurrentTaskLimiterImpl() { + assert(outstanding_tasks_ == 0); +} + +const std::string& ConcurrentTaskLimiterImpl::GetName() const { + return name_; +} + +void ConcurrentTaskLimiterImpl::SetMaxOutstandingTask(int32_t limit) { + max_outstanding_tasks_.store(limit, std::memory_order_relaxed); +} + +void ConcurrentTaskLimiterImpl::ResetMaxOutstandingTask() { + max_outstanding_tasks_.store(-1, std::memory_order_relaxed); +} + +int32_t ConcurrentTaskLimiterImpl::GetOutstandingTask() const { + return outstanding_tasks_.load(std::memory_order_relaxed); +} + +std::unique_ptr<TaskLimiterToken> ConcurrentTaskLimiterImpl::GetToken( + bool force) { + int32_t limit = max_outstanding_tasks_.load(std::memory_order_relaxed); + int32_t tasks = outstanding_tasks_.load(std::memory_order_relaxed); + // force = true, bypass the throttle. + // limit < 0 means unlimited tasks. + while (force || limit < 0 || tasks < limit) { + if (outstanding_tasks_.compare_exchange_weak(tasks, tasks + 1)) { + return std::unique_ptr<TaskLimiterToken>(new TaskLimiterToken(this)); + } + } + return nullptr; +} + +ConcurrentTaskLimiter* NewConcurrentTaskLimiter( + const std::string& name, int32_t limit) { + return new ConcurrentTaskLimiterImpl(name, limit); +} + +TaskLimiterToken::~TaskLimiterToken() { + --limiter_->outstanding_tasks_; + assert(limiter_->outstanding_tasks_ >= 0); +} + +} // namespace ROCKSDB_NAMESPACE |