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505accda38
Summary: Scoped anonymous enums seem to be better supported than static constexpr at the moment, so this diff replaces the latter with the former. Also, this diff removes an incorrect inclusion of pthread.h. MSVC build was broken starting with D50439. Test Plan: 1. build 2. observe proper skiplist behavior by absence of pathological slowdown 3. push diff to tmp_try_windows branch to tickle AppVeyor 4. wait for contbuild before committing to master Reviewers: sdong Reviewed By: sdong Subscribers: dhruba Differential Revision: https://reviews.facebook.net/D50517
39 lines
1,002 B
C++
39 lines
1,002 B
C++
// Copyright (c) 2013, Facebook, Inc. All rights reserved.
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// This source code is licensed under the BSD-style license found in the
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// LICENSE file in the root directory of this source tree. An additional grant
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// of patent rights can be found in the PATENTS file in the same directory.
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//
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#include "util/random.h"
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#include <stdint.h>
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#include <string.h>
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#include <thread>
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#include <utility>
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#include "port/likely.h"
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#include "util/thread_local.h"
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#if ROCKSDB_SUPPORT_THREAD_LOCAL
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#define STORAGE_DECL static __thread
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#else
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#define STORAGE_DECL static
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#endif
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namespace rocksdb {
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Random* Random::GetTLSInstance() {
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STORAGE_DECL Random* tls_instance;
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STORAGE_DECL std::aligned_storage<sizeof(Random)>::type tls_instance_bytes;
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auto rv = tls_instance;
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if (UNLIKELY(rv == nullptr)) {
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size_t seed = std::hash<std::thread::id>()(std::this_thread::get_id());
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rv = new (&tls_instance_bytes) Random((uint32_t)seed);
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tls_instance = rv;
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}
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return rv;
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}
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} // namespace rocksdb
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