base_set_assoc.cc revision 12513:4dfc54394b5a 
1/*
2 * Copyright (c) 2012-2014 ARM Limited
3 * All rights reserved.
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
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8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder.  You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Copyright (c) 2003-2005,2014 The Regents of The University of Michigan
15 * All rights reserved.
16 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions are
19 * met: redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer;
21 * redistributions in binary form must reproduce the above copyright
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24 * neither the name of the copyright holders nor the names of its
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26 * this software without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 *
40 * Authors: Erik Hallnor
41 */
42
43/**
44 * @file
45 * Definitions of a base set associative tag store.
46 */
47
48#include "mem/cache/tags/base_set_assoc.hh"
49
50#include <string>
51
52#include "base/intmath.hh"
53#include "sim/core.hh"
54
55using namespace std;
56
57BaseSetAssoc::BaseSetAssoc(const Params *p)
58    :BaseTags(p), assoc(p->assoc), allocAssoc(p->assoc),
59     numSets(p->size / (p->block_size * p->assoc)),
60     sequentialAccess(p->sequential_access)
61{
62    // Check parameters
63    if (blkSize < 4 || !isPowerOf2(blkSize)) {
64        fatal("Block size must be at least 4 and a power of 2");
65    }
66    if (!isPowerOf2(numSets)) {
67        fatal("# of sets must be non-zero and a power of 2");
68    }
69    if (assoc <= 0) {
70        fatal("associativity must be greater than zero");
71    }
72
73    setShift = floorLog2(blkSize);
74    setMask = numSets - 1;
75    tagShift = setShift + floorLog2(numSets);
76
77    sets = new SetType[numSets];
78    blks = new BlkType[numSets * assoc];
79    // allocate data storage in one big chunk
80    numBlocks = numSets * assoc;
81    dataBlks = new uint8_t[numBlocks * blkSize];
82
83    unsigned blkIndex = 0;       // index into blks array
84    for (unsigned i = 0; i < numSets; ++i) {
85        sets[i].assoc = assoc;
86
87        sets[i].blks = new BlkType*[assoc];
88
89        // link in the data blocks
90        for (unsigned j = 0; j < assoc; ++j) {
91            // locate next cache block
92            BlkType *blk = &blks[blkIndex];
93            blk->data = &dataBlks[blkSize*blkIndex];
94            ++blkIndex;
95
96            // invalidate new cache block
97            blk->invalidate();
98
99            //EGH Fix Me : do we need to initialize blk?
100
101            // Setting the tag to j is just to prevent long chains in the hash
102            // table; won't matter because the block is invalid
103            blk->tag = j;
104            blk->whenReady = 0;
105            blk->isTouched = false;
106            sets[i].blks[j]=blk;
107            blk->set = i;
108            blk->way = j;
109        }
110    }
111}
112
113BaseSetAssoc::~BaseSetAssoc()
114{
115    delete [] dataBlks;
116    delete [] blks;
117    delete [] sets;
118}
119
120CacheBlk*
121BaseSetAssoc::findBlock(Addr addr, bool is_secure) const
122{
123    Addr tag = extractTag(addr);
124    unsigned set = extractSet(addr);
125    BlkType *blk = sets[set].findBlk(tag, is_secure);
126    return blk;
127}
128
129CacheBlk*
130BaseSetAssoc::findBlockBySetAndWay(int set, int way) const
131{
132    return sets[set].blks[way];
133}
134
135std::string
136BaseSetAssoc::print() const {
137    std::string cache_state;
138    for (unsigned i = 0; i < numSets; ++i) {
139        // link in the data blocks
140        for (unsigned j = 0; j < assoc; ++j) {
141            BlkType *blk = sets[i].blks[j];
142            if (blk->isValid())
143                cache_state += csprintf("\tset: %d block: %d %s\n", i, j,
144                        blk->print());
145        }
146    }
147    if (cache_state.empty())
148        cache_state = "no valid tags\n";
149    return cache_state;
150}
151
152void
153BaseSetAssoc::cleanupRefs()
154{
155    for (unsigned i = 0; i < numSets*assoc; ++i) {
156        if (blks[i].isValid()) {
157            totalRefs += blks[i].refCount;
158            ++sampledRefs;
159        }
160    }
161}
162
163void
164BaseSetAssoc::computeStats()
165{
166    for (unsigned i = 0; i < ContextSwitchTaskId::NumTaskId; ++i) {
167        occupanciesTaskId[i] = 0;
168        for (unsigned j = 0; j < 5; ++j) {
169            ageTaskId[i][j] = 0;
170        }
171    }
172
173    for (unsigned i = 0; i < numSets * assoc; ++i) {
174        if (blks[i].isValid()) {
175            assert(blks[i].task_id < ContextSwitchTaskId::NumTaskId);
176            occupanciesTaskId[blks[i].task_id]++;
177            assert(blks[i].tickInserted <= curTick());
178            Tick age = curTick() - blks[i].tickInserted;
179
180            int age_index;
181            if (age / SimClock::Int::us < 10) { // <10us
182                age_index = 0;
183            } else if (age / SimClock::Int::us < 100) { // <100us
184                age_index = 1;
185            } else if (age / SimClock::Int::ms < 1) { // <1ms
186                age_index = 2;
187            } else if (age / SimClock::Int::ms < 10) { // <10ms
188                age_index = 3;
189            } else
190                age_index = 4; // >10ms
191
192            ageTaskId[blks[i].task_id][age_index]++;
193        }
194    }
195}
196