base_set_assoc.cc revision 10941:a39646f4c407 
1/*
2 * Copyright (c) 2012-2014 ARM Limited
3 * All rights reserved.
4 *
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11 * unmodified and in its entirety in all distributions of the software,
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13 *
14 * Copyright (c) 2003-2005,2014 The Regents of The University of Michigan
15 * All rights reserved.
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18 * modification, are permitted provided that the following conditions are
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28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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39 *
40 * Authors: Erik Hallnor
41 */
42
43/**
44 * @file
45 * Definitions of a base set associative tag store.
46 */
47
48#include <string>
49
50#include "base/intmath.hh"
51#include "mem/cache/tags/base_set_assoc.hh"
52#include "sim/core.hh"
53
54using namespace std;
55
56BaseSetAssoc::BaseSetAssoc(const Params *p)
57    :BaseTags(p), assoc(p->assoc), allocAssoc(p->assoc),
58     numSets(p->size / (p->block_size * p->assoc)),
59     sequentialAccess(p->sequential_access)
60{
61    // Check parameters
62    if (blkSize < 4 || !isPowerOf2(blkSize)) {
63        fatal("Block size must be at least 4 and a power of 2");
64    }
65    if (numSets <= 0 || !isPowerOf2(numSets)) {
66        fatal("# of sets must be non-zero and a power of 2");
67    }
68    if (assoc <= 0) {
69        fatal("associativity must be greater than zero");
70    }
71
72    blkMask = blkSize - 1;
73    setShift = floorLog2(blkSize);
74    setMask = numSets - 1;
75    tagShift = setShift + floorLog2(numSets);
76    /** @todo Make warmup percentage a parameter. */
77    warmupBound = numSets * assoc;
78
79    sets = new SetType[numSets];
80    blks = new BlkType[numSets * assoc];
81    // allocate data storage in one big chunk
82    numBlocks = numSets * assoc;
83    dataBlks = new uint8_t[numBlocks * blkSize];
84
85    unsigned blkIndex = 0;       // index into blks array
86    for (unsigned i = 0; i < numSets; ++i) {
87        sets[i].assoc = assoc;
88
89        sets[i].blks = new BlkType*[assoc];
90
91        // link in the data blocks
92        for (unsigned j = 0; j < assoc; ++j) {
93            // locate next cache block
94            BlkType *blk = &blks[blkIndex];
95            blk->data = &dataBlks[blkSize*blkIndex];
96            ++blkIndex;
97
98            // invalidate new cache block
99            blk->invalidate();
100
101            //EGH Fix Me : do we need to initialize blk?
102
103            // Setting the tag to j is just to prevent long chains in the hash
104            // table; won't matter because the block is invalid
105            blk->tag = j;
106            blk->whenReady = 0;
107            blk->isTouched = false;
108            blk->size = blkSize;
109            sets[i].blks[j]=blk;
110            blk->set = i;
111            blk->way = j;
112        }
113    }
114}
115
116BaseSetAssoc::~BaseSetAssoc()
117{
118    delete [] dataBlks;
119    delete [] blks;
120    delete [] sets;
121}
122
123CacheBlk*
124BaseSetAssoc::findBlock(Addr addr, bool is_secure) const
125{
126    Addr tag = extractTag(addr);
127    unsigned set = extractSet(addr);
128    BlkType *blk = sets[set].findBlk(tag, is_secure);
129    return blk;
130}
131
132CacheBlk*
133BaseSetAssoc::findBlockBySetAndWay(int set, int way) const
134{
135    return sets[set].blks[way];
136}
137
138void
139BaseSetAssoc::clearLocks()
140{
141    for (int i = 0; i < numBlocks; i++){
142        blks[i].clearLoadLocks();
143    }
144}
145
146std::string
147BaseSetAssoc::print() const {
148    std::string cache_state;
149    for (unsigned i = 0; i < numSets; ++i) {
150        // link in the data blocks
151        for (unsigned j = 0; j < assoc; ++j) {
152            BlkType *blk = sets[i].blks[j];
153            if (blk->isValid())
154                cache_state += csprintf("\tset: %d block: %d %s\n", i, j,
155                        blk->print());
156        }
157    }
158    if (cache_state.empty())
159        cache_state = "no valid tags\n";
160    return cache_state;
161}
162
163void
164BaseSetAssoc::cleanupRefs()
165{
166    for (unsigned i = 0; i < numSets*assoc; ++i) {
167        if (blks[i].isValid()) {
168            totalRefs += blks[i].refCount;
169            ++sampledRefs;
170        }
171    }
172}
173
174void
175BaseSetAssoc::computeStats()
176{
177    for (unsigned i = 0; i < ContextSwitchTaskId::NumTaskId; ++i) {
178        occupanciesTaskId[i] = 0;
179        for (unsigned j = 0; j < 5; ++j) {
180            ageTaskId[i][j] = 0;
181        }
182    }
183
184    for (unsigned i = 0; i < numSets * assoc; ++i) {
185        if (blks[i].isValid()) {
186            assert(blks[i].task_id < ContextSwitchTaskId::NumTaskId);
187            occupanciesTaskId[blks[i].task_id]++;
188            assert(blks[i].tickInserted <= curTick());
189            Tick age = curTick() - blks[i].tickInserted;
190
191            int age_index;
192            if (age / SimClock::Int::us < 10) { // <10us
193                age_index = 0;
194            } else if (age / SimClock::Int::us < 100) { // <100us
195                age_index = 1;
196            } else if (age / SimClock::Int::ms < 1) { // <1ms
197                age_index = 2;
198            } else if (age / SimClock::Int::ms < 10) { // <10ms
199                age_index = 3;
200            } else
201                age_index = 4; // >10ms
202
203            ageTaskId[blks[i].task_id][age_index]++;
204        }
205    }
206}
207