1/*
2 * Copyright (c) 2013,2016,2018 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 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
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38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 *
40 * Authors: Erik Hallnor
41 * Ron Dreslinski
42 */
43
44/**
45 * @file
46 * Definitions of BaseTags.
47 */
48
49#include "mem/cache/tags/base.hh"
50
51#include <cassert>
52
53#include "base/types.hh"
54#include "mem/cache/base.hh"
55#include "mem/cache/tags/indexing_policies/base.hh"
56#include "mem/request.hh"
57#include "sim/core.hh"
58#include "sim/sim_exit.hh"
59#include "sim/system.hh"
60
61BaseTags::BaseTags(const Params *p)
62 : ClockedObject(p), blkSize(p->block_size), blkMask(blkSize - 1),
63 size(p->size),
64 lookupLatency(p->tag_latency),
65 accessLatency(p->sequential_access ?
66 p->tag_latency + p->data_latency :
67 std::max(p->tag_latency, p->data_latency)),
67 cache(nullptr),
68 cache(nullptr), indexingPolicy(p->indexing_policy),
69 warmupBound((p->warmup_percentage/100.0) * (p->size / p->block_size)),
70 warmedUp(false), numBlocks(p->size / p->block_size),
71 dataBlks(new uint8_t[p->size]) // Allocate data storage in one big chunk
72{
73}
74
75void
76BaseTags::setCache(BaseCache *_cache)
77{
78 assert(!cache);
79 cache = _cache;
80}
81
81std::vector<ReplaceableEntry*>
82BaseTags::getPossibleLocations(const Addr addr) const
82ReplaceableEntry*
83BaseTags::findBlockBySetAndWay(int set, int way) const
84{
84 panic("Unimplemented getPossibleLocations for tags subclass");
85 return indexingPolicy->getEntry(set, way);
86}
87
88CacheBlk*
89BaseTags::findBlock(Addr addr, bool is_secure) const
90{
91 // Extract block tag
92 Addr tag = extractTag(addr);
93
93 // Find possible locations for the given address
94 const std::vector<ReplaceableEntry*> locations =
95 getPossibleLocations(addr);
94 // Find possible entries that may contain the given address
95 const std::vector<ReplaceableEntry*> entries =
96 indexingPolicy->getPossibleEntries(addr);
97
98 // Search for block
98 for (const auto& location : locations) {
99 for (const auto& location : entries) {
100 CacheBlk* blk = static_cast<CacheBlk*>(location);
101 if ((blk->tag == tag) && blk->isValid() &&
102 (blk->isSecure() == is_secure)) {
103 return blk;
104 }
105 }
106
107 // Did not find block
108 return nullptr;
109}
110
111void
112BaseTags::insertBlock(const Addr addr, const bool is_secure,
113 const int src_master_ID, const uint32_t task_ID,
114 CacheBlk *blk)
115{
116 assert(!blk->isValid());
117
118 // Previous block, if existed, has been removed, and now we have
119 // to insert the new one
120 // Deal with what we are bringing in
121 assert(src_master_ID < cache->system->maxMasters());
122 occupancies[src_master_ID]++;
123
124 // Insert block with tag, src master id and task id
125 blk->insert(extractTag(addr), is_secure, src_master_ID, task_ID);
126
127 // Check if cache warm up is done
128 if (!warmedUp && tagsInUse.value() >= warmupBound) {
129 warmedUp = true;
130 warmupCycle = curTick();
131 }
132
133 // We only need to write into one tag and one data block.
134 tagAccesses += 1;
135 dataAccesses += 1;
136}
137
138Addr
139BaseTags::extractTag(const Addr addr) const
140{
141 return indexingPolicy->extractTag(addr);
142}
143
144void
145BaseTags::cleanupRefsVisitor(CacheBlk &blk)
146{
147 if (blk.isValid()) {
148 totalRefs += blk.refCount;
149 ++sampledRefs;
150 }
151}
152
153void
154BaseTags::cleanupRefs()
155{
156 forEachBlk([this](CacheBlk &blk) { cleanupRefsVisitor(blk); });
157}
158
159void
160BaseTags::computeStatsVisitor(CacheBlk &blk)
161{
162 if (blk.isValid()) {
163 assert(blk.task_id < ContextSwitchTaskId::NumTaskId);
164 occupanciesTaskId[blk.task_id]++;
165 assert(blk.tickInserted <= curTick());
166 Tick age = curTick() - blk.tickInserted;
167
168 int age_index;
169 if (age / SimClock::Int::us < 10) { // <10us
170 age_index = 0;
171 } else if (age / SimClock::Int::us < 100) { // <100us
172 age_index = 1;
173 } else if (age / SimClock::Int::ms < 1) { // <1ms
174 age_index = 2;
175 } else if (age / SimClock::Int::ms < 10) { // <10ms
176 age_index = 3;
177 } else
178 age_index = 4; // >10ms
179
180 ageTaskId[blk.task_id][age_index]++;
181 }
182}
183
184void
185BaseTags::computeStats()
186{
187 for (unsigned i = 0; i < ContextSwitchTaskId::NumTaskId; ++i) {
188 occupanciesTaskId[i] = 0;
189 for (unsigned j = 0; j < 5; ++j) {
190 ageTaskId[i][j] = 0;
191 }
192 }
193
194 forEachBlk([this](CacheBlk &blk) { computeStatsVisitor(blk); });
195}
196
197std::string
198BaseTags::print()
199{
200 std::string str;
201
202 auto print_blk = [&str](CacheBlk &blk) {
203 if (blk.isValid())
204 str += csprintf("\tset: %x, way: %x %s\n", blk.getSet(),
205 blk.getWay(), blk.print());
206 };
207 forEachBlk(print_blk);
208
209 if (str.empty())
210 str = "no valid tags\n";
211
212 return str;
213}
214
215void
216BaseTags::regStats()
217{
218 ClockedObject::regStats();
219
220 using namespace Stats;
221
222 tagsInUse
223 .name(name() + ".tagsinuse")
224 .desc("Cycle average of tags in use")
225 ;
226
227 totalRefs
228 .name(name() + ".total_refs")
229 .desc("Total number of references to valid blocks.")
230 ;
231
232 sampledRefs
233 .name(name() + ".sampled_refs")
234 .desc("Sample count of references to valid blocks.")
235 ;
236
237 avgRefs
238 .name(name() + ".avg_refs")
239 .desc("Average number of references to valid blocks.")
240 ;
241
242 avgRefs = totalRefs/sampledRefs;
243
244 warmupCycle
245 .name(name() + ".warmup_cycle")
246 .desc("Cycle when the warmup percentage was hit.")
247 ;
248
249 occupancies
250 .init(cache->system->maxMasters())
251 .name(name() + ".occ_blocks")
252 .desc("Average occupied blocks per requestor")
253 .flags(nozero | nonan)
254 ;
255 for (int i = 0; i < cache->system->maxMasters(); i++) {
256 occupancies.subname(i, cache->system->getMasterName(i));
257 }
258
259 avgOccs
260 .name(name() + ".occ_percent")
261 .desc("Average percentage of cache occupancy")
262 .flags(nozero | total)
263 ;
264 for (int i = 0; i < cache->system->maxMasters(); i++) {
265 avgOccs.subname(i, cache->system->getMasterName(i));
266 }
267
268 avgOccs = occupancies / Stats::constant(numBlocks);
269
270 occupanciesTaskId
271 .init(ContextSwitchTaskId::NumTaskId)
272 .name(name() + ".occ_task_id_blocks")
273 .desc("Occupied blocks per task id")
274 .flags(nozero | nonan)
275 ;
276
277 ageTaskId
278 .init(ContextSwitchTaskId::NumTaskId, 5)
279 .name(name() + ".age_task_id_blocks")
280 .desc("Occupied blocks per task id")
281 .flags(nozero | nonan)
282 ;
283
284 percentOccsTaskId
285 .name(name() + ".occ_task_id_percent")
286 .desc("Percentage of cache occupancy per task id")
287 .flags(nozero)
288 ;
289
290 percentOccsTaskId = occupanciesTaskId / Stats::constant(numBlocks);
291
292 tagAccesses
293 .name(name() + ".tag_accesses")
294 .desc("Number of tag accesses")
295 ;
296
297 dataAccesses
298 .name(name() + ".data_accesses")
299 .desc("Number of data accesses")
300 ;
301
302 registerDumpCallback(new BaseTagsDumpCallback(this));
303 registerExitCallback(new BaseTagsCallback(this));
304}