summaryrefslogtreecommitdiff
path: root/src/mem/ruby/system/CacheMemory.cc
blob: ea5054e4c58894d313ce461d400a89c18acfe089 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
/*
 * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met: redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer;
 * redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution;
 * neither the name of the copyright holders nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "base/intmath.hh"
#include "mem/ruby/system/CacheMemory.hh"

using namespace std;

ostream&
operator<<(ostream& out, const CacheMemory& obj)
{
    obj.print(out);
    out << flush;
    return out;
}

CacheMemory *
RubyCacheParams::create()
{
    return new CacheMemory(this);
}

CacheMemory::CacheMemory(const Params *p)
    : SimObject(p)
{
    m_cache_size = p->size;
    m_latency = p->latency;
    m_cache_assoc = p->assoc;
    m_policy = p->replacement_policy;
    m_profiler_ptr = new CacheProfiler(name());
    m_start_index_bit = p->start_index_bit;
}

void
CacheMemory::init()
{
    m_cache_num_sets = (m_cache_size / m_cache_assoc) /
        RubySystem::getBlockSizeBytes();
    assert(m_cache_num_sets > 1);
    m_cache_num_set_bits = floorLog2(m_cache_num_sets);
    assert(m_cache_num_set_bits > 0);

    if (m_policy == "PSEUDO_LRU")
        m_replacementPolicy_ptr =
            new PseudoLRUPolicy(m_cache_num_sets, m_cache_assoc);
    else if (m_policy == "LRU")
        m_replacementPolicy_ptr =
            new LRUPolicy(m_cache_num_sets, m_cache_assoc);
    else
        assert(false);

    m_cache.resize(m_cache_num_sets);
    for (int i = 0; i < m_cache_num_sets; i++) {
        m_cache[i].resize(m_cache_assoc);
        for (int j = 0; j < m_cache_assoc; j++) {
            m_cache[i][j] = NULL;
        }
    }
}

CacheMemory::~CacheMemory()
{
    if (m_replacementPolicy_ptr != NULL)
        delete m_replacementPolicy_ptr;
    delete m_profiler_ptr;
    for (int i = 0; i < m_cache_num_sets; i++) {
        for (int j = 0; j < m_cache_assoc; j++) {
            delete m_cache[i][j];
        }
    }
}

void
CacheMemory::printConfig(ostream& out)
{
    int block_size = RubySystem::getBlockSizeBytes();

    out << "Cache config: " << m_cache_name << endl;
    out << "  cache_associativity: " << m_cache_assoc << endl;
    out << "  num_cache_sets_bits: " << m_cache_num_set_bits << endl;
    const int cache_num_sets = 1 << m_cache_num_set_bits;
    out << "  num_cache_sets: " << cache_num_sets << endl;
    out << "  cache_set_size_bytes: " << cache_num_sets * block_size << endl;
    out << "  cache_set_size_Kbytes: "
        << double(cache_num_sets * block_size) / (1<<10) << endl;
    out << "  cache_set_size_Mbytes: "
        << double(cache_num_sets * block_size) / (1<<20) << endl;
    out << "  cache_size_bytes: "
        << cache_num_sets * block_size * m_cache_assoc << endl;
    out << "  cache_size_Kbytes: "
        << double(cache_num_sets * block_size * m_cache_assoc) / (1<<10)
        << endl;
    out << "  cache_size_Mbytes: "
        << double(cache_num_sets * block_size * m_cache_assoc) / (1<<20)
        << endl;
}

// convert a Address to its location in the cache
Index
CacheMemory::addressToCacheSet(const Address& address) const
{
    assert(address == line_address(address));
    return address.bitSelect(m_start_index_bit,
                             m_start_index_bit + m_cache_num_set_bits - 1);
}

// Given a cache index: returns the index of the tag in a set.
// returns -1 if the tag is not found.
int
CacheMemory::findTagInSet(Index cacheSet, const Address& tag) const
{
    assert(tag == line_address(tag));
    // search the set for the tags
    m5::hash_map<Address, int>::const_iterator it = m_tag_index.find(tag);
    if (it != m_tag_index.end())
        if (m_cache[cacheSet][it->second]->m_Permission !=
            AccessPermission_NotPresent)
            return it->second;
    return -1; // Not found
}

// Given a cache index: returns the index of the tag in a set.
// returns -1 if the tag is not found.
int
CacheMemory::findTagInSetIgnorePermissions(Index cacheSet,
                                           const Address& tag) const
{
    assert(tag == line_address(tag));
    // search the set for the tags
    m5::hash_map<Address, int>::const_iterator it = m_tag_index.find(tag);
    if (it != m_tag_index.end())
        return it->second;
    return -1; // Not found
}

bool
CacheMemory::tryCacheAccess(const Address& address, RubyRequestType type,
                            DataBlock*& data_ptr)
{
    assert(address == line_address(address));
    DPRINTF(RubyCache, "address: %s\n", address);
    Index cacheSet = addressToCacheSet(address);
    int loc = findTagInSet(cacheSet, address);
    if (loc != -1) {
        // Do we even have a tag match?
        AbstractCacheEntry* entry = m_cache[cacheSet][loc];
        m_replacementPolicy_ptr->
            touch(cacheSet, loc, g_eventQueue_ptr->getTime());
        data_ptr = &(entry->getDataBlk());

        if (entry->m_Permission == AccessPermission_Read_Write) {
            return true;
        }
        if ((entry->m_Permission == AccessPermission_Read_Only) &&
            (type == RubyRequestType_LD || type == RubyRequestType_IFETCH)) {
            return true;
        }
        // The line must not be accessible
    }
    data_ptr = NULL;
    return false;
}

bool
CacheMemory::testCacheAccess(const Address& address, RubyRequestType type,
                             DataBlock*& data_ptr)
{
    assert(address == line_address(address));
    DPRINTF(RubyCache, "address: %s\n", address);
    Index cacheSet = addressToCacheSet(address);
    int loc = findTagInSet(cacheSet, address);

    if (loc != -1) {
        // Do we even have a tag match?
        AbstractCacheEntry* entry = m_cache[cacheSet][loc];
        m_replacementPolicy_ptr->
            touch(cacheSet, loc, g_eventQueue_ptr->getTime());
        data_ptr = &(entry->getDataBlk());

        return m_cache[cacheSet][loc]->m_Permission !=
            AccessPermission_NotPresent;
    }

    data_ptr = NULL;
    return false;
}

// tests to see if an address is present in the cache
bool
CacheMemory::isTagPresent(const Address& address) const
{
    assert(address == line_address(address));
    Index cacheSet = addressToCacheSet(address);
    int loc = findTagInSet(cacheSet, address);

    if (loc == -1) {
        // We didn't find the tag
        DPRINTF(RubyCache, "No tag match for address: %s\n", address);
        return false;
    }
    DPRINTF(RubyCache, "address: %s found\n", address);
    return true;
}

// Returns true if there is:
//   a) a tag match on this address or there is
//   b) an unused line in the same cache "way"
bool
CacheMemory::cacheAvail(const Address& address) const
{
    assert(address == line_address(address));

    Index cacheSet = addressToCacheSet(address);

    for (int i = 0; i < m_cache_assoc; i++) {
        AbstractCacheEntry* entry = m_cache[cacheSet][i];
        if (entry != NULL) {
            if (entry->m_Address == address ||
                entry->m_Permission == AccessPermission_NotPresent) {
                // Already in the cache or we found an empty entry
                return true;
            }
        } else {
            return true;
        }
    }
    return false;
}

AbstractCacheEntry*
CacheMemory::allocate(const Address& address, AbstractCacheEntry* entry)
{
    assert(address == line_address(address));
    assert(!isTagPresent(address));
    assert(cacheAvail(address));
    DPRINTF(RubyCache, "address: %s\n", address);

    // Find the first open slot
    Index cacheSet = addressToCacheSet(address);
    std::vector<AbstractCacheEntry*> &set = m_cache[cacheSet];
    for (int i = 0; i < m_cache_assoc; i++) {
        if (!set[i] || set[i]->m_Permission == AccessPermission_NotPresent) {
            set[i] = entry;  // Init entry
            set[i]->m_Address = address;
            set[i]->m_Permission = AccessPermission_Invalid;
            DPRINTF(RubyCache, "Allocate clearing lock for addr: %x\n",
                    address);
            set[i]->m_locked = -1;
            m_tag_index[address] = i;

            m_replacementPolicy_ptr->
                touch(cacheSet, i, g_eventQueue_ptr->getTime());

            return entry;
        }
    }
    panic("Allocate didn't find an available entry");
}

void
CacheMemory::deallocate(const Address& address)
{
    assert(address == line_address(address));
    assert(isTagPresent(address));
    DPRINTF(RubyCache, "address: %s\n", address);
    Index cacheSet = addressToCacheSet(address);
    int loc = findTagInSet(cacheSet, address);
    if (loc != -1) {
        delete m_cache[cacheSet][loc];
        m_cache[cacheSet][loc] = NULL;
        m_tag_index.erase(address);
    }
}

// Returns with the physical address of the conflicting cache line
Address
CacheMemory::cacheProbe(const Address& address) const
{
    assert(address == line_address(address));
    assert(!cacheAvail(address));

    Index cacheSet = addressToCacheSet(address);
    return m_cache[cacheSet][m_replacementPolicy_ptr->getVictim(cacheSet)]->
        m_Address;
}

// looks an address up in the cache
AbstractCacheEntry*
CacheMemory::lookup(const Address& address)
{
    assert(address == line_address(address));
    Index cacheSet = addressToCacheSet(address);
    int loc = findTagInSet(cacheSet, address);
    if(loc == -1) return NULL;
    return m_cache[cacheSet][loc];
}

// looks an address up in the cache
const AbstractCacheEntry*
CacheMemory::lookup(const Address& address) const
{
    assert(address == line_address(address));
    Index cacheSet = addressToCacheSet(address);
    int loc = findTagInSet(cacheSet, address);
    if(loc == -1) return NULL;
    return m_cache[cacheSet][loc];
}

// Sets the most recently used bit for a cache block
void
CacheMemory::setMRU(const Address& address)
{
    Index cacheSet;

    cacheSet = addressToCacheSet(address);
    m_replacementPolicy_ptr->
        touch(cacheSet, findTagInSet(cacheSet, address),
              g_eventQueue_ptr->getTime());
}

void
CacheMemory::profileMiss(const CacheMsg& msg)
{
    m_profiler_ptr->addCacheStatSample(msg.getType(), 
                                       msg.getAccessMode(),
                                       msg.getPrefetch());
}

void
CacheMemory::profileGenericRequest(GenericRequestType requestType,
                                   RubyAccessMode accessType,
                                   PrefetchBit pfBit)
{
    m_profiler_ptr->addGenericStatSample(requestType, 
                                         accessType, 
                                         pfBit);
}

void
CacheMemory::recordCacheContents(CacheRecorder& tr) const
{
    for (int i = 0; i < m_cache_num_sets; i++) {
        for (int j = 0; j < m_cache_assoc; j++) {
            AccessPermission perm = m_cache[i][j]->m_Permission;
            RubyRequestType request_type = RubyRequestType_NULL;
            if (perm == AccessPermission_Read_Only) {
                if (m_is_instruction_only_cache) {
                    request_type = RubyRequestType_IFETCH;
                } else {
                    request_type = RubyRequestType_LD;
                }
            } else if (perm == AccessPermission_Read_Write) {
                request_type = RubyRequestType_ST;
            }

            if (request_type != RubyRequestType_NULL) {
#if 0
                tr.addRecord(m_chip_ptr->getID(), m_cache[i][j].m_Address,
                             Address(0), request_type,
                             m_replacementPolicy_ptr->getLastAccess(i, j));
#endif
            }
        }
    }
}

void
CacheMemory::print(ostream& out) const
{
    out << "Cache dump: " << m_cache_name << endl;
    for (int i = 0; i < m_cache_num_sets; i++) {
        for (int j = 0; j < m_cache_assoc; j++) {
            if (m_cache[i][j] != NULL) {
                out << "  Index: " << i
                    << " way: " << j
                    << " entry: " << *m_cache[i][j] << endl;
            } else {
                out << "  Index: " << i
                    << " way: " << j
                    << " entry: NULL" << endl;
            }
        }
    }
}

void
CacheMemory::printData(ostream& out) const
{
    out << "printData() not supported" << endl;
}

void
CacheMemory::clearStats() const
{
    m_profiler_ptr->clearStats();
}

void
CacheMemory::printStats(ostream& out) const
{
    m_profiler_ptr->printStats(out);
}

void
CacheMemory::getMemoryValue(const Address& addr, char* value,
                            unsigned size_in_bytes)
{
    AbstractCacheEntry* entry = lookup(line_address(addr));
    unsigned startByte = addr.getAddress() - line_address(addr).getAddress();
    for (unsigned i = 0; i < size_in_bytes; ++i) {
        value[i] = entry->getDataBlk().getByte(i + startByte);
    }
}

void
CacheMemory::setMemoryValue(const Address& addr, char* value,
                            unsigned size_in_bytes)
{
    AbstractCacheEntry* entry = lookup(line_address(addr));
    unsigned startByte = addr.getAddress() - line_address(addr).getAddress();
    assert(size_in_bytes > 0);
    for (unsigned i = 0; i < size_in_bytes; ++i) {
        entry->getDataBlk().setByte(i + startByte, value[i]);
    }

    // entry = lookup(line_address(addr));
}

void
CacheMemory::setLocked(const Address& address, int context)
{
    DPRINTF(RubyCache, "Setting Lock for addr: %x to %d\n", address, context);
    assert(address == line_address(address));
    Index cacheSet = addressToCacheSet(address);
    int loc = findTagInSet(cacheSet, address);
    assert(loc != -1);
    m_cache[cacheSet][loc]->m_locked = context;
}

void
CacheMemory::clearLocked(const Address& address)
{
    DPRINTF(RubyCache, "Clear Lock for addr: %x\n", address);
    assert(address == line_address(address));
    Index cacheSet = addressToCacheSet(address);
    int loc = findTagInSet(cacheSet, address);
    assert(loc != -1);
    m_cache[cacheSet][loc]->m_locked = -1;
}

bool
CacheMemory::isLocked(const Address& address, int context)
{
    assert(address == line_address(address));
    Index cacheSet = addressToCacheSet(address);
    int loc = findTagInSet(cacheSet, address);
    assert(loc != -1);
    DPRINTF(RubyCache, "Testing Lock for addr: %llx cur %d con %d\n",
            address, m_cache[cacheSet][loc]->m_locked, context);
    return m_cache[cacheSet][loc]->m_locked == context;
}