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diff --git a/src/rocksdb/test_util/sync_point.h b/src/rocksdb/test_util/sync_point.h
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+++ b/src/rocksdb/test_util/sync_point.h
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+//  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).
+#pragma once
+
+#include <assert.h>
+#include <functional>
+#include <mutex>
+#include <string>
+#include <thread>
+#include <vector>
+
+#include "rocksdb/rocksdb_namespace.h"
+
+// This is only set from db_stress.cc and for testing only.
+// If non-zero, kill at various points in source code with probability 1/this
+extern int rocksdb_kill_odds;
+// If kill point has a prefix on this list, will skip killing.
+extern std::vector<std::string> rocksdb_kill_prefix_blacklist;
+
+#ifdef NDEBUG
+// empty in release build
+#define TEST_KILL_RANDOM(kill_point, rocksdb_kill_odds)
+#else
+
+namespace ROCKSDB_NAMESPACE {
+// Kill the process with probability 1/odds for testing.
+extern void TestKillRandom(std::string kill_point, int odds,
+                           const std::string& srcfile, int srcline);
+
+// To avoid crashing always at some frequently executed codepaths (during
+// kill random test), use this factor to reduce odds
+#define REDUCE_ODDS 2
+#define REDUCE_ODDS2 4
+
+#define TEST_KILL_RANDOM(kill_point, rocksdb_kill_odds)                  \
+  {                                                                      \
+    if (rocksdb_kill_odds > 0) {                                         \
+      TestKillRandom(kill_point, rocksdb_kill_odds, __FILE__, __LINE__); \
+    }                                                                    \
+  }
+}  // namespace ROCKSDB_NAMESPACE
+#endif
+
+#ifdef NDEBUG
+#define TEST_SYNC_POINT(x)
+#define TEST_IDX_SYNC_POINT(x, index)
+#define TEST_SYNC_POINT_CALLBACK(x, y)
+#define INIT_SYNC_POINT_SINGLETONS()
+#else
+
+namespace ROCKSDB_NAMESPACE {
+
+// This class provides facility to reproduce race conditions deterministically
+// in unit tests.
+// Developer could specify sync points in the codebase via TEST_SYNC_POINT.
+// Each sync point represents a position in the execution stream of a thread.
+// In the unit test, 'Happens After' relationship among sync points could be
+// setup via SyncPoint::LoadDependency, to reproduce a desired interleave of
+// threads execution.
+// Refer to (DBTest,TransactionLogIteratorRace), for an example use case.
+
+class SyncPoint {
+ public:
+  static SyncPoint* GetInstance();
+
+  SyncPoint(const SyncPoint&) = delete;
+  SyncPoint& operator=(const SyncPoint&) = delete;
+  ~SyncPoint();
+
+  struct SyncPointPair {
+    std::string predecessor;
+    std::string successor;
+  };
+
+  // call once at the beginning of a test to setup the dependency between
+  // sync points
+  void LoadDependency(const std::vector<SyncPointPair>& dependencies);
+
+  // call once at the beginning of a test to setup the dependency between
+  // sync points and setup markers indicating the successor is only enabled
+  // when it is processed on the same thread as the predecessor.
+  // When adding a marker, it implicitly adds a dependency for the marker pair.
+  void LoadDependencyAndMarkers(const std::vector<SyncPointPair>& dependencies,
+                                const std::vector<SyncPointPair>& markers);
+
+  // The argument to the callback is passed through from
+  // TEST_SYNC_POINT_CALLBACK(); nullptr if TEST_SYNC_POINT or
+  // TEST_IDX_SYNC_POINT was used.
+  void SetCallBack(const std::string& point,
+                   const std::function<void(void*)>& callback);
+
+  // Clear callback function by point
+  void ClearCallBack(const std::string& point);
+
+  // Clear all call back functions.
+  void ClearAllCallBacks();
+
+  // enable sync point processing (disabled on startup)
+  void EnableProcessing();
+
+  // disable sync point processing
+  void DisableProcessing();
+
+  // remove the execution trace of all sync points
+  void ClearTrace();
+
+  // triggered by TEST_SYNC_POINT, blocking execution until all predecessors
+  // are executed.
+  // And/or call registered callback function, with argument `cb_arg`
+  void Process(const std::string& point, void* cb_arg = nullptr);
+
+  // TODO: it might be useful to provide a function that blocks until all
+  // sync points are cleared.
+
+  // We want this to be public so we can
+  // subclass the implementation
+  struct Data;
+
+ private:
+   // Singleton
+  SyncPoint();
+  Data*  impl_;
+};
+
+}  // namespace ROCKSDB_NAMESPACE
+
+// Use TEST_SYNC_POINT to specify sync points inside code base.
+// Sync points can have happens-after depedency on other sync points,
+// configured at runtime via SyncPoint::LoadDependency. This could be
+// utilized to re-produce race conditions between threads.
+// See TransactionLogIteratorRace in db_test.cc for an example use case.
+// TEST_SYNC_POINT is no op in release build.
+#define TEST_SYNC_POINT(x) \
+  ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->Process(x)
+#define TEST_IDX_SYNC_POINT(x, index)                      \
+  ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->Process(x + \
+                                                       std::to_string(index))
+#define TEST_SYNC_POINT_CALLBACK(x, y) \
+  ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->Process(x, y)
+#define INIT_SYNC_POINT_SINGLETONS() \
+  (void)ROCKSDB_NAMESPACE::SyncPoint::GetInstance();
+#endif  // NDEBUG