initial code repo

[stor4nfv.git] / src / ceph / src / erasure-code / isa / ErasureCodeIsaTableCache.h

diff --git a/src/ceph/src/erasure-code/isa/ErasureCodeIsaTableCache.h b/src/ceph/src/erasure-code/isa/ErasureCodeIsaTableCache.h
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+++ b/src/ceph/src/erasure-code/isa/ErasureCodeIsaTableCache.h
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+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2014 CERN (Switzerland)
+ *
+ * Author: Andreas-Joachim Peters <Andreas.Joachim.Peters@cern.ch>
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ */
+
+/**
+ * @file   ErasureCodeIsaTableCache.h
+ *
+ * @brief  Erasure Code Isa CODEC Table Cache
+ *
+ * The INTEL ISA-L library supports two pre-defined encoding matrices (cauchy = default, reed_sol_van = default)
+ * The default CODEC implementation using these two matrices is implemented in class ErasureCodeIsaDefault.
+ * ISA-L allows to use custom matrices which might be added later as implementations deriving from the base class ErasoreCodeIsa.
+ */
+
+#ifndef CEPH_ERASURE_CODE_ISA_TABLE_CACHE_H
+#define CEPH_ERASURE_CODE_ISA_TABLE_CACHE_H
+
+// -----------------------------------------------------------------------------
+#include "common/Mutex.h"
+#include "erasure-code/ErasureCodeInterface.h"
+// -----------------------------------------------------------------------------
+#include <list>
+// -----------------------------------------------------------------------------
+
+class ErasureCodeIsaTableCache {
+  // ---------------------------------------------------------------------------
+  // This class implements a table cache for encoding and decoding matrices.
+  // Encoding matrices are shared for the same (k,m) combination. It supplies
+  // a decoding matrix lru cache which is shared for identical
+  // matrix types e.g. there is one cache (lru-list + lru-map) for Cauchy and
+  // one for Vandermonde matrices!
+  // ---------------------------------------------------------------------------
+
+public:
+
+  // the cache size is sufficient up to (12,4) decodings
+
+  static const int decoding_tables_lru_length = 2516;
+
+  typedef std::pair<std::list<std::string>::iterator, bufferptr> lru_entry_t;
+  typedef std::map< int, unsigned char** > codec_table_t;
+  typedef std::map< int, codec_table_t > codec_tables_t;
+  typedef std::map< int, codec_tables_t > codec_technique_tables_t;
+
+  typedef std::map< std::string, lru_entry_t > lru_map_t;
+  typedef std::list< std::string > lru_list_t;
+
+  ErasureCodeIsaTableCache() :
+  codec_tables_guard("isa-lru-cache")
+  {
+  }
+
+  virtual ~ErasureCodeIsaTableCache();
+
+  Mutex codec_tables_guard; // mutex used to protect modifications in encoding/decoding table maps
+
+  bool getDecodingTableFromCache(std::string &signature,
+                                 unsigned char* &table,
+                                 int matrixtype,
+                                 int k,
+                                 int m);
+
+  void putDecodingTableToCache(std::string&,
+                               unsigned char*&,
+                               int matrixtype,
+                               int k,
+                               int m);
+
+  unsigned char** getEncodingTable(int matrix, int k, int m);
+  unsigned char** getEncodingCoefficient(int matrix, int k, int m);
+
+  unsigned char** getEncodingTableNoLock(int matrix, int k, int m);
+  unsigned char** getEncodingCoefficientNoLock(int matrix, int k, int m);
+
+  unsigned char* setEncodingTable(int matrix, int k, int m, unsigned char*);
+  unsigned char* setEncodingCoefficient(int matrix, int k, int m, unsigned char*);
+
+  int getDecodingTableCacheSize(int matrixtype = 0);
+
+private:
+  codec_technique_tables_t encoding_coefficient; // encoding coefficients accessed via table[matrix][k][m]
+  codec_technique_tables_t encoding_table; // encoding coefficients accessed via table[matrix][k][m]
+
+  std::map<int, lru_map_t*> decoding_tables; // decoding table cache accessed via map[matrixtype]
+  std::map<int, lru_list_t*> decoding_tables_lru; // decoding table lru list accessed via list[matrixtype]
+
+  lru_map_t* getDecodingTables(int matrix_type);
+
+  lru_list_t* getDecodingTablesLru(int matrix_type);
+
+  Mutex* getLock();
+
+};
+
+#endif