ceph/src/rocksdb/utilities/transactions/optimistic_transaction.h

   1 // Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
   2 //  This source code is licensed under both the GPLv2 (found in the
   3 //  COPYING file in the root directory) and Apache 2.0 License
   4 //  (found in the LICENSE.Apache file in the root directory).
   5
   6 #pragma once
   7
   8 #ifndef ROCKSDB_LITE
   9
  10 #include <stack>
  11 #include <string>
  12 #include <unordered_map>
  13 #include <vector>
  14
  15 #include "db/write_callback.h"
  16 #include "rocksdb/db.h"
  17 #include "rocksdb/slice.h"
  18 #include "rocksdb/snapshot.h"
  19 #include "rocksdb/status.h"
  20 #include "rocksdb/types.h"
  21 #include "rocksdb/utilities/optimistic_transaction_db.h"
  22 #include "rocksdb/utilities/transaction.h"
  23 #include "rocksdb/utilities/write_batch_with_index.h"
  24 #include "utilities/transactions/transaction_base.h"
  25 #include "utilities/transactions/transaction_util.h"
  26
  27 namespace ROCKSDB_NAMESPACE {
  28
  29 class OptimisticTransaction : public TransactionBaseImpl {
  30  public:
  31   OptimisticTransaction(OptimisticTransactionDB* db,
  32                         const WriteOptions& write_options,
  33                         const OptimisticTransactionOptions& txn_options);
  34   // No copying allowed
  35   OptimisticTransaction(const OptimisticTransaction&) = delete;
  36   void operator=(const OptimisticTransaction&) = delete;
  37
  38   virtual ~OptimisticTransaction();
  39
  40   void Reinitialize(OptimisticTransactionDB* txn_db,
  41                     const WriteOptions& write_options,
  42                     const OptimisticTransactionOptions& txn_options);
  43
  44   Status Prepare() override;
  45
  46   Status Commit() override;
  47
  48   Status Rollback() override;
  49
  50   Status SetName(const TransactionName& name) override;
  51
  52  protected:
  53   Status TryLock(ColumnFamilyHandle* column_family, const Slice& key,
  54                  bool read_only, bool exclusive, const bool do_validate = true,
  55                  const bool assume_tracked = false) override;
  56
  57  private:
  58   ROCKSDB_FIELD_UNUSED OptimisticTransactionDB* const txn_db_;
  59
  60   friend class OptimisticTransactionCallback;
  61
  62   void Initialize(const OptimisticTransactionOptions& txn_options);
  63
  64   // Returns OK if it is safe to commit this transaction.  Returns Status::Busy
  65   // if there are read or write conflicts that would prevent us from committing
  66   // OR if we can not determine whether there would be any such conflicts.
  67   //
  68   // Should only be called on writer thread.
  69   Status CheckTransactionForConflicts(DB* db);
  70
  71   void Clear() override;
  72
  73   void UnlockGetForUpdate(ColumnFamilyHandle* /* unused */,
  74                           const Slice& /* unused */) override {
  75     // Nothing to unlock.
  76   }
  77
  78   Status CommitWithSerialValidate();
  79
  80   Status CommitWithParallelValidate();
  81 };
  82
  83 // Used at commit time to trigger transaction validation
  84 class OptimisticTransactionCallback : public WriteCallback {
  85  public:
  86   explicit OptimisticTransactionCallback(OptimisticTransaction* txn)
  87       : txn_(txn) {}
  88
  89   Status Callback(DB* db) override {
  90     return txn_->CheckTransactionForConflicts(db);
  91   }
  92
  93   bool AllowWriteBatching() override { return false; }
  94
  95  private:
  96   OptimisticTransaction* txn_;
  97 };
  98
  99 }  // namespace ROCKSDB_NAMESPACE
 100
 101 #endif  // ROCKSDB_LITE