junction/extra/impl/MapAdapter_CDS_Cuckoo.h

   1 /*------------------------------------------------------------------------
   2   Junction: Concurrent data structures in C++
   3   Copyright (c) 2016 Jeff Preshing
   4
   5   Distributed under the Simplified BSD License.
   6   Original location: https://github.com/preshing/junction
   7
   8   This software is distributed WITHOUT ANY WARRANTY; without even the
   9   implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  10   See the LICENSE file for more information.
  11 ------------------------------------------------------------------------*/
  12
  13 #ifndef JUNCTION_EXTRA_IMPL_MAPADAPTER_CDS_CUCKOO_H
  14 #define JUNCTION_EXTRA_IMPL_MAPADAPTER_CDS_CUCKOO_H
  15
  16 #include <junction/Core.h>
  17
  18 #if !JUNCTION_WITH_CDS
  19 #error "You must configure with JUNCTION_WITH_CDS=1!"
  20 #endif
  21
  22 #include <junction/MapTraits.h>
  23 #include <cds/init.h>
  24 #include <cds/gc/hp.h>
  25 #include <memory.h> // memcpy required by cuckoo_map.h
  26 #include <cds/container/cuckoo_map.h>
  27
  28 namespace junction {
  29 namespace extra {
  30
  31 class MapAdapter {
  32 public:
  33     static TURF_CONSTEXPR const char* MapName = "CDS CuckooMap";
  34
  35     cds::gc::HP* m_hpGC;
  36
  37     MapAdapter(ureg) {
  38         cds::Initialize();
  39         m_hpGC = new cds::gc::HP;
  40     }
  41
  42     ~MapAdapter() {
  43         delete m_hpGC;
  44         cds::Terminate();
  45     }
  46
  47     class ThreadContext {
  48     public:
  49         ThreadContext(MapAdapter&, ureg) {
  50         }
  51
  52         void registerThread() {
  53             cds::threading::Manager::attachThread();
  54         }
  55
  56         void unregisterThread() {
  57             cds::threading::Manager::detachThread();
  58         }
  59
  60         void update() {
  61         }
  62     };
  63
  64     class Map {
  65     private:
  66         struct Hash1 {
  67             size_t operator()(u32 s) const {
  68                 return junction::hash(s);
  69             }
  70         };
  71
  72         struct Hash2 {
  73             size_t operator()(u32 s) const {
  74                 return junction::hash(s + 0x9e3779b9);
  75             }
  76         };
  77
  78         struct Traits : cds::container::cuckoo::traits {
  79             typedef std::equal_to<u32> equal_to;
  80             typedef cds::opt::hash_tuple<Hash1, Hash2> hash;
  81         };
  82
  83         cds::container::CuckooMap<u32, void*, Traits> m_map;
  84
  85     public:
  86         Map(ureg capacity) : m_map() {
  87         }
  88
  89         void set(u32 key, void* value) {
  90             m_map.insert(key, value);
  91         }
  92
  93         void* get(u32 key) {
  94             void* result = NULL;
  95             m_map.find(key, [&result](std::pair<const u32, void*>& item) { result = item.second; });
  96             return result;
  97         }
  98
  99         void erase(u32 key) {
 100             m_map.erase(key);
 101         }
 102     };
 103
 104     static ureg getInitialCapacity(ureg maxPopulation) {
 105         return maxPopulation / 4;
 106     }
 107 };
 108
 109 } // namespace extra
 110 } // namespace junction
 111
 112 #endif // JUNCTION_EXTRA_IMPL_MAPADAPTER_CDS_CUCKOO_H