blob: a0fc7331f535c4e8e94ffbad5e812c03fd828411 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
// 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
|
