1/*
2 * Copyright 2014-present Facebook, Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <folly/synchronization/LifoSem.h>
18
19/// Raw node storage is preallocated in a contiguous memory segment,
20/// but we use an anonymous mmap so the physical memory used (RSS) will
21/// only reflect the maximum number of waiters that actually existed
22/// concurrently. For blocked threads the max node count is limited by the
23/// number of threads, so we can conservatively estimate that this will be
24/// < 10k. For LifoEventSem, however, we could potentially have many more.
25///
26/// On a 64-bit architecture each LifoSemRawNode takes 16 bytes. We make
27/// the pool 1 million entries.
28
29LIFOSEM_DECLARE_POOL(std::atomic, 1000000)
30
31namespace folly {
32
33ShutdownSemError::ShutdownSemError(const std::string& msg)
34 : std::runtime_error(msg) {}
35
36ShutdownSemError::~ShutdownSemError() noexcept {}
37
38} // namespace folly
39