base_set_assoc.cc revision 12679:6c416cb3ca06 
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
7 * property including but not limited to intellectual property relating
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
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution;
24 * neither the name of the copyright holders nor the names of its
25 * contributors may be used to endorse or promote products derived from
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
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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
55BaseSetAssoc::BaseSetAssoc(const Params *p)
56    :BaseTags(p), assoc(p->assoc), allocAssoc(p->assoc),
57     blks(p->size / p->block_size),
58     numSets(p->size / (p->block_size * p->assoc)),
59     sequentialAccess(p->sequential_access),
60     sets(p->size / (p->block_size * p->assoc)),
61     replacementPolicy(p->replacement_policy)
62{
63    // Check parameters
64    if (blkSize < 4 || !isPowerOf2(blkSize)) {
65        fatal("Block size must be at least 4 and a power of 2");
66    }
67    if (!isPowerOf2(numSets)) {
68        fatal("# of sets must be non-zero and a power of 2");
69    }
70    if (assoc <= 0) {
71        fatal("associativity must be greater than zero");
72    }
73
74    setShift = floorLog2(blkSize);
75    setMask = numSets - 1;
76    tagShift = setShift + floorLog2(numSets);
77
78    unsigned blkIndex = 0;       // index into blks array
79    for (unsigned i = 0; i < numSets; ++i) {
80        sets[i].assoc = assoc;
81
82        sets[i].blks.resize(assoc);
83
84        // link in the data blocks
85        for (unsigned j = 0; j < assoc; ++j) {
86            // Select block within the set to be linked
87            BlkType*& blk = sets[i].blks[j];
88
89            // Locate next cache block
90            blk = &blks[blkIndex];
91
92            // Associate a data chunk to the block
93            blk->data = &dataBlks[blkSize*blkIndex];
94
95            // Setting the tag to j is just to prevent long chains in the
96            // hash table; won't matter because the block is invalid
97            blk->tag = j;
98
99            // Set its set and way
100            blk->set = i;
101            blk->way = j;
102
103            // Update block index
104            ++blkIndex;
105        }
106    }
107}
108
109CacheBlk*
110BaseSetAssoc::findBlock(Addr addr, bool is_secure) const
111{
112    Addr tag = extractTag(addr);
113    unsigned set = extractSet(addr);
114    BlkType *blk = sets[set].findBlk(tag, is_secure);
115    return blk;
116}
117
118CacheBlk*
119BaseSetAssoc::findBlockBySetAndWay(int set, int way) const
120{
121    return sets[set].blks[way];
122}
123
124std::string
125BaseSetAssoc::print() const {
126    std::string cache_state;
127    for (const CacheBlk& blk : blks) {
128        if (blk.isValid())
129            cache_state += csprintf("\tset: %d way: %d %s\n", blk.set,
130                                    blk.way, blk.print());
131    }
132    if (cache_state.empty())
133        cache_state = "no valid tags\n";
134    return cache_state;
135}
136
137void
138BaseSetAssoc::cleanupRefs()
139{
140    for (const CacheBlk& blk : blks) {
141        if (blk.isValid()) {
142            totalRefs += blk.refCount;
143            ++sampledRefs;
144        }
145    }
146}
147
148void
149BaseSetAssoc::computeStats()
150{
151    for (unsigned i = 0; i < ContextSwitchTaskId::NumTaskId; ++i) {
152        occupanciesTaskId[i] = 0;
153        for (unsigned j = 0; j < 5; ++j) {
154            ageTaskId[i][j] = 0;
155        }
156    }
157
158    for (const CacheBlk& blk : blks) {
159        if (blk.isValid()) {
160            assert(blk.task_id < ContextSwitchTaskId::NumTaskId);
161            occupanciesTaskId[blk.task_id]++;
162            assert(blk.tickInserted <= curTick());
163            Tick age = curTick() - blk.tickInserted;
164
165            int age_index;
166            if (age / SimClock::Int::us < 10) { // <10us
167                age_index = 0;
168            } else if (age / SimClock::Int::us < 100) { // <100us
169                age_index = 1;
170            } else if (age / SimClock::Int::ms < 1) { // <1ms
171                age_index = 2;
172            } else if (age / SimClock::Int::ms < 10) { // <10ms
173                age_index = 3;
174            } else
175                age_index = 4; // >10ms
176
177            ageTaskId[blk.task_id][age_index]++;
178        }
179    }
180}
181
182BaseSetAssoc *
183BaseSetAssocParams::create()
184{
185    return new BaseSetAssoc(this);
186}
187