lfu_rp.hh revision 12628:458d655f2abb 
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 Frequently Used replacement policy.
34 * The victim is chosen using the reference frequency. The least referenced
35 * block is always chosen to be evicted, regardless of the amount of times
36 * it has been touched, or how long has passed since its last touch.
37 */
38
39#ifndef __MEM_CACHE_REPLACEMENT_POLICIES_LFU_RP_HH__
40#define __MEM_CACHE_REPLACEMENT_POLICIES_LFU_RP_HH__
41
42#include "mem/cache/replacement_policies/base.hh"
43#include "params/LFURP.hh"
44
45class LFURP : public BaseReplacementPolicy
46{
47  public:
48    /** Convenience typedef. */
49    typedef LFURPParams Params;
50
51    /**
52     * Construct and initiliaze this replacement policy.
53     */
54    LFURP(const Params *p);
55
56    /**
57     * Destructor.
58     */
59    ~LFURP() {}
60
61    /**
62     * Find replacement victim using reference frequency.
63     *
64     * @param cands Replacement candidates, selected by indexing policy.
65     * @return Cache block to be replaced.
66     */
67    CacheBlk* getVictim(const ReplacementCandidates& candidates) override;
68};
69
70#endif // __MEM_CACHE_REPLACEMENT_POLICIES_LFU_RP_HH__
71