1/**
2 * Copyright (c) 2018 Inria
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Daniel Carvalho
29 */
30
31/**
32 * @file
33 * Declaration of a Least Recently Used replacement policy.
| 1/**
2 * Copyright (c) 2018 Inria
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Daniel Carvalho
29 */
30
31/**
32 * @file
33 * Declaration of a Least Recently Used replacement policy.
|
36 */
37
38#ifndef __MEM_CACHE_REPLACEMENT_POLICIES_LRU_RP_HH__
39#define __MEM_CACHE_REPLACEMENT_POLICIES_LRU_RP_HH__
40
41#include "mem/cache/replacement_policies/base.hh"
42
43struct LRURPParams;
44
45class LRURP : public BaseReplacementPolicy
46{
47 protected:
48 /** LRU-specific implementation of replacement data. */
49 struct LRUReplData : ReplacementData
50 {
51 /** Tick on which the entry was last touched. */
52 Tick lastTouchTick;
53
54 /**
55 * Default constructor. Invalidate data.
56 */
57 LRUReplData() : lastTouchTick(0) {}
58 };
59
60 public:
61 /** Convenience typedef. */
62 typedef LRURPParams Params;
63
64 /**
65 * Construct and initiliaze this replacement policy.
66 */
67 LRURP(const Params *p);
68
69 /**
70 * Destructor.
71 */
72 ~LRURP() {}
73
74 /**
75 * Invalidate replacement data to set it as the next probable victim.
76 * Sets its last touch tick as the starting tick.
77 *
78 * @param replacement_data Replacement data to be invalidated.
79 */
80 void invalidate(const std::shared_ptr<ReplacementData>& replacement_data)
81 const override;
82
83 /**
84 * Touch an entry to update its replacement data.
85 * Sets its last touch tick as the current tick.
86 *
87 * @param replacement_data Replacement data to be touched.
88 */
89 void touch(const std::shared_ptr<ReplacementData>& replacement_data) const
90 override;
91
92 /**
93 * Reset replacement data. Used when an entry is inserted.
94 * Sets its last touch tick as the current tick.
95 *
96 * @param replacement_data Replacement data to be reset.
97 */
98 void reset(const std::shared_ptr<ReplacementData>& replacement_data) const
99 override;
100
101 /**
102 * Find replacement victim using LRU timestamps.
103 *
104 * @param candidates Replacement candidates, selected by indexing policy.
105 * @return Replacement entry to be replaced.
106 */
107 ReplaceableEntry* getVictim(const ReplacementCandidates& candidates) const
108 override;
109
110 /**
111 * Instantiate a replacement data entry.
112 *
113 * @return A shared pointer to the new replacement data.
114 */
115 std::shared_ptr<ReplacementData> instantiateEntry() override;
116};
117
118#endif // __MEM_CACHE_REPLACEMENT_POLICIES_LRU_RP_HH__
| 35 */
36
37#ifndef __MEM_CACHE_REPLACEMENT_POLICIES_LRU_RP_HH__
38#define __MEM_CACHE_REPLACEMENT_POLICIES_LRU_RP_HH__
39
40#include "mem/cache/replacement_policies/base.hh"
41
42struct LRURPParams;
43
44class LRURP : public BaseReplacementPolicy
45{
46 protected:
47 /** LRU-specific implementation of replacement data. */
48 struct LRUReplData : ReplacementData
49 {
50 /** Tick on which the entry was last touched. */
51 Tick lastTouchTick;
52
53 /**
54 * Default constructor. Invalidate data.
55 */
56 LRUReplData() : lastTouchTick(0) {}
57 };
58
59 public:
60 /** Convenience typedef. */
61 typedef LRURPParams Params;
62
63 /**
64 * Construct and initiliaze this replacement policy.
65 */
66 LRURP(const Params *p);
67
68 /**
69 * Destructor.
70 */
71 ~LRURP() {}
72
73 /**
74 * Invalidate replacement data to set it as the next probable victim.
75 * Sets its last touch tick as the starting tick.
76 *
77 * @param replacement_data Replacement data to be invalidated.
78 */
79 void invalidate(const std::shared_ptr<ReplacementData>& replacement_data)
80 const override;
81
82 /**
83 * Touch an entry to update its replacement data.
84 * Sets its last touch tick as the current tick.
85 *
86 * @param replacement_data Replacement data to be touched.
87 */
88 void touch(const std::shared_ptr<ReplacementData>& replacement_data) const
89 override;
90
91 /**
92 * Reset replacement data. Used when an entry is inserted.
93 * Sets its last touch tick as the current tick.
94 *
95 * @param replacement_data Replacement data to be reset.
96 */
97 void reset(const std::shared_ptr<ReplacementData>& replacement_data) const
98 override;
99
100 /**
101 * Find replacement victim using LRU timestamps.
102 *
103 * @param candidates Replacement candidates, selected by indexing policy.
104 * @return Replacement entry to be replaced.
105 */
106 ReplaceableEntry* getVictim(const ReplacementCandidates& candidates) const
107 override;
108
109 /**
110 * Instantiate a replacement data entry.
111 *
112 * @return A shared pointer to the new replacement data.
113 */
114 std::shared_ptr<ReplacementData> instantiateEntry() override;
115};
116
117#endif // __MEM_CACHE_REPLACEMENT_POLICIES_LRU_RP_HH__
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