rocksdb/util/sync_point.h

124 lines
4.4 KiB
C
Raw Normal View History

// Copyright (c) 2014, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
#pragma once
#include <assert.h>
#include <condition_variable>
#include <mutex>
#include <string>
#include <unordered_set>
#include <unordered_map>
#include <vector>
// 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 {
// Kill the process with probablity 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
#endif
#ifdef NDEBUG
#define TEST_SYNC_POINT(x)
#define TEST_SYNC_POINT_CALLBACK(x, y)
#else
2014-04-17 23:29:06 +02:00
namespace rocksdb {
// 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 exmaple use case.
class SyncPoint {
public:
static SyncPoint* GetInstance();
struct Dependency {
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<Dependency>& dependencies);
// Set up a call back function in sync point.
void SetCallBack(const std::string point,
std::function<void(void*)> callback);
// 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 functionn, 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.
private:
bool PredecessorsAllCleared(const std::string& point);
// successor/predecessor map loaded from LoadDependency
std::unordered_map<std::string, std::vector<std::string>> successors_;
std::unordered_map<std::string, std::vector<std::string>> predecessors_;
std::unordered_map<std::string, std::function<void(void*)> > callbacks_;
std::mutex mutex_;
std::condition_variable cv_;
// sync points that have been passed through
std::unordered_set<std::string> cleared_points_;
bool enabled_ = false;
int num_callbacks_running_ = 0;
};
} // namespace rocksdb
// 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::SyncPoint::GetInstance()->Process(x)
#define TEST_SYNC_POINT_CALLBACK(x, y) \
rocksdb::SyncPoint::GetInstance()->Process(x, y)
#endif // NDEBUG