src/mem/physical.cc

   1 /*
   2  * Copyright (c) 2001-2005 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  *
  28  * Authors: Ron Dreslinski
  29  *          Ali Saidi
  30  */
  31
  32 #include <sys/types.h>
  33 #include <sys/mman.h>
  34 #include <errno.h>
  35 #include <fcntl.h>
  36 #include <unistd.h>
  37 #include <zlib.h>
  38
  39 #include <cstdio>
  40 #include <iostream>
  41 #include <string>
  42
  43 #include "arch/registers.hh"
  44 #include "base/misc.hh"
  45 #include "base/random.hh"
  46 #include "base/types.hh"
  47 #include "config/full_system.hh"
  48 #include "config/the_isa.hh"
  49 #include "mem/packet_access.hh"
  50 #include "mem/physical.hh"
  51 #include "sim/eventq.hh"
  52
  53 using namespace std;
  54 using namespace TheISA;
  55
  56 PhysicalMemory::PhysicalMemory(const Params *p)
  57     : MemObject(p), pmemAddr(NULL), pagePtr(0),
  58       lat(p->latency), lat_var(p->latency_var),
  59       cachedSize(params()->range.size()), cachedStart(params()->range.start)
  60 {
  61     if (params()->range.size() % TheISA::PageBytes != 0)
  62         panic("Memory Size not divisible by page size\n");
  63
  64     if (params()->null)
  65         return;
  66
  67     int map_flags = MAP_ANON | MAP_PRIVATE;
  68     pmemAddr = (uint8_t *)mmap(NULL, params()->range.size(),
  69                                PROT_READ | PROT_WRITE, map_flags, -1, 0);
  70
  71     if (pmemAddr == (void *)MAP_FAILED) {
  72         perror("mmap");
  73         fatal("Could not mmap!\n");
  74     }
  75
  76     //If requested, initialize all the memory to 0
  77     if (p->zero)
  78         memset(pmemAddr, 0, p->range.size());
  79 }
  80
  81 void
  82 PhysicalMemory::init()
  83 {
  84     if (ports.size() == 0) {
  85         fatal("PhysicalMemory object %s is unconnected!", name());
  86     }
  87
  88     for (PortIterator pi = ports.begin(); pi != ports.end(); ++pi) {
  89         if (*pi)
  90             (*pi)->sendStatusChange(Port::RangeChange);
  91     }
  92 }
  93
  94 PhysicalMemory::~PhysicalMemory()
  95 {
  96     if (pmemAddr)
  97         munmap((char*)pmemAddr, params()->range.size());
  98     //Remove memPorts?
  99 }
 100
 101 Addr
 102 PhysicalMemory::new_page()
 103 {
 104     Addr return_addr = pagePtr << LogVMPageSize;
 105     return_addr += start();
 106
 107     ++pagePtr;
 108     return return_addr;
 109 }
 110
 111 unsigned
 112 PhysicalMemory::deviceBlockSize() const
 113 {
 114     //Can accept anysize request
 115     return 0;
 116 }
 117
 118 Tick
 119 PhysicalMemory::calculateLatency(PacketPtr pkt)
 120 {
 121     Tick latency = lat;
 122     if (lat_var != 0)
 123         latency += random_mt.random<Tick>(0, lat_var);
 124     return latency;
 125 }
 126
 127
 128
 129 // Add load-locked to tracking list.  Should only be called if the
 130 // operation is a load and the LLSC flag is set.
 131 void
 132 PhysicalMemory::trackLoadLocked(PacketPtr pkt)
 133 {
 134     Request *req = pkt->req;
 135     Addr paddr = LockedAddr::mask(req->getPaddr());
 136
 137     // first we check if we already have a locked addr for this
 138     // xc.  Since each xc only gets one, we just update the
 139     // existing record with the new address.
 140     list<LockedAddr>::iterator i;
 141
 142     for (i = lockedAddrList.begin(); i != lockedAddrList.end(); ++i) {
 143         if (i->matchesContext(req)) {
 144             DPRINTF(LLSC, "Modifying lock record: context %d addr %#x\n",
 145                     req->contextId(), paddr);
 146             i->addr = paddr;
 147             return;
 148         }
 149     }
 150
 151     // no record for this xc: need to allocate a new one
 152     DPRINTF(LLSC, "Adding lock record: context %d addr %#x\n",
 153             req->contextId(), paddr);
 154     lockedAddrList.push_front(LockedAddr(req));
 155 }
 156
 157
 158 // Called on *writes* only... both regular stores and
 159 // store-conditional operations.  Check for conventional stores which
 160 // conflict with locked addresses, and for success/failure of store
 161 // conditionals.
 162 bool
 163 PhysicalMemory::checkLockedAddrList(PacketPtr pkt)
 164 {
 165     Request *req = pkt->req;
 166     Addr paddr = LockedAddr::mask(req->getPaddr());
 167     bool isLLSC = pkt->isLLSC();
 168
 169     // Initialize return value.  Non-conditional stores always
 170     // succeed.  Assume conditional stores will fail until proven
 171     // otherwise.
 172     bool success = !isLLSC;
 173
 174     // Iterate over list.  Note that there could be multiple matching
 175     // records, as more than one context could have done a load locked
 176     // to this location.
 177     list<LockedAddr>::iterator i = lockedAddrList.begin();
 178
 179     while (i != lockedAddrList.end()) {
 180
 181         if (i->addr == paddr) {
 182             // we have a matching address
 183
 184             if (isLLSC && i->matchesContext(req)) {
 185                 // it's a store conditional, and as far as the memory
 186                 // system can tell, the requesting context's lock is
 187                 // still valid.
 188                 DPRINTF(LLSC, "StCond success: context %d addr %#x\n",
 189                         req->contextId(), paddr);
 190                 success = true;
 191             }
 192
 193             // Get rid of our record of this lock and advance to next
 194             DPRINTF(LLSC, "Erasing lock record: context %d addr %#x\n",
 195                     i->contextId, paddr);
 196             i = lockedAddrList.erase(i);
 197         }
 198         else {
 199             // no match: advance to next record
 200             ++i;
 201         }
 202     }
 203
 204     if (isLLSC) {
 205         req->setExtraData(success ? 1 : 0);
 206     }
 207
 208     return success;
 209 }
 210
 211
 212 #if TRACING_ON
 213
 214 #define CASE(A, T)                                                      \
 215   case sizeof(T):                                                       \
 216     DPRINTF(MemoryAccess,"%s of size %i on address 0x%x data 0x%x\n",   \
 217             A, pkt->getSize(), pkt->getAddr(), pkt->get<T>());          \
 218   break
 219
 220
 221 #define TRACE_PACKET(A)                                                 \
 222     do {                                                                \
 223         switch (pkt->getSize()) {                                       \
 224           CASE(A, uint64_t);                                            \
 225           CASE(A, uint32_t);                                            \
 226           CASE(A, uint16_t);                                            \
 227           CASE(A, uint8_t);                                             \
 228           default:                                                      \
 229             DPRINTF(MemoryAccess, "%s of size %i on address 0x%x\n",    \
 230                     A, pkt->getSize(), pkt->getAddr());                 \
 231         }                                                               \
 232     } while (0)
 233
 234 #else
 235
 236 #define TRACE_PACKET(A)
 237
 238 #endif
 239
 240 Tick
 241 PhysicalMemory::doAtomicAccess(PacketPtr pkt)
 242 {
 243     assert(pkt->getAddr() >= start() &&
 244            pkt->getAddr() + pkt->getSize() <= start() + size());
 245
 246     if (pkt->memInhibitAsserted()) {
 247         DPRINTF(MemoryAccess, "mem inhibited on 0x%x: not responding\n",
 248                 pkt->getAddr());
 249         return 0;
 250     }
 251
 252     uint8_t *hostAddr = pmemAddr + pkt->getAddr() - start();
 253
 254     if (pkt->cmd == MemCmd::SwapReq) {
 255         IntReg overwrite_val;
 256         bool overwrite_mem;
 257         uint64_t condition_val64;
 258         uint32_t condition_val32;
 259
 260         if (!pmemAddr)
 261             panic("Swap only works if there is real memory (i.e. null=False)");
 262         assert(sizeof(IntReg) >= pkt->getSize());
 263
 264         overwrite_mem = true;
 265         // keep a copy of our possible write value, and copy what is at the
 266         // memory address into the packet
 267         std::memcpy(&overwrite_val, pkt->getPtr<uint8_t>(), pkt->getSize());
 268         std::memcpy(pkt->getPtr<uint8_t>(), hostAddr, pkt->getSize());
 269
 270         if (pkt->req->isCondSwap()) {
 271             if (pkt->getSize() == sizeof(uint64_t)) {
 272                 condition_val64 = pkt->req->getExtraData();
 273                 overwrite_mem = !std::memcmp(&condition_val64, hostAddr,
 274                                              sizeof(uint64_t));
 275             } else if (pkt->getSize() == sizeof(uint32_t)) {
 276                 condition_val32 = (uint32_t)pkt->req->getExtraData();
 277                 overwrite_mem = !std::memcmp(&condition_val32, hostAddr,
 278                                              sizeof(uint32_t));
 279             } else
 280                 panic("Invalid size for conditional read/write\n");
 281         }
 282
 283         if (overwrite_mem)
 284             std::memcpy(hostAddr, &overwrite_val, pkt->getSize());
 285
 286         assert(!pkt->req->isInstFetch());
 287         TRACE_PACKET("Read/Write");
 288     } else if (pkt->isRead()) {
 289         assert(!pkt->isWrite());
 290         if (pkt->isLLSC()) {
 291             trackLoadLocked(pkt);
 292         }
 293         if (pmemAddr)
 294             memcpy(pkt->getPtr<uint8_t>(), hostAddr, pkt->getSize());
 295         TRACE_PACKET(pkt->req->isInstFetch() ? "IFetch" : "Read");
 296     } else if (pkt->isWrite()) {
 297         if (writeOK(pkt)) {
 298             if (pmemAddr)
 299                 memcpy(hostAddr, pkt->getPtr<uint8_t>(), pkt->getSize());
 300             assert(!pkt->req->isInstFetch());
 301             TRACE_PACKET("Write");
 302         }
 303     } else if (pkt->isInvalidate()) {
 304         //upgrade or invalidate
 305         if (pkt->needsResponse()) {
 306             pkt->makeAtomicResponse();
 307         }
 308     } else {
 309         panic("unimplemented");
 310     }
 311
 312     if (pkt->needsResponse()) {
 313         pkt->makeAtomicResponse();
 314     }
 315     return calculateLatency(pkt);
 316 }
 317
 318
 319 void
 320 PhysicalMemory::doFunctionalAccess(PacketPtr pkt)
 321 {
 322     assert(pkt->getAddr() >= start() &&
 323            pkt->getAddr() + pkt->getSize() <= start() + size());
 324
 325
 326     uint8_t *hostAddr = pmemAddr + pkt->getAddr() - start();
 327
 328     if (pkt->isRead()) {
 329         if (pmemAddr)
 330             memcpy(pkt->getPtr<uint8_t>(), hostAddr, pkt->getSize());
 331         TRACE_PACKET("Read");
 332         pkt->makeAtomicResponse();
 333     } else if (pkt->isWrite()) {
 334         if (pmemAddr)
 335             memcpy(hostAddr, pkt->getPtr<uint8_t>(), pkt->getSize());
 336         TRACE_PACKET("Write");
 337         pkt->makeAtomicResponse();
 338     } else if (pkt->isPrint()) {
 339         Packet::PrintReqState *prs =
 340             dynamic_cast<Packet::PrintReqState*>(pkt->senderState);
 341         // Need to call printLabels() explicitly since we're not going
 342         // through printObj().
 343         prs->printLabels();
 344         // Right now we just print the single byte at the specified address.
 345         ccprintf(prs->os, "%s%#x\n", prs->curPrefix(), *hostAddr);
 346     } else {
 347         panic("PhysicalMemory: unimplemented functional command %s",
 348               pkt->cmdString());
 349     }
 350 }
 351
 352
 353 Port *
 354 PhysicalMemory::getPort(const std::string &if_name, int idx)
 355 {
 356     // Accept request for "functional" port for backwards compatibility
 357     // with places where this function is called from C++.  I'd prefer
 358     // to move all these into Python someday.
 359     if (if_name == "functional") {
 360         return new MemoryPort(csprintf("%s-functional", name()), this);
 361     }
 362
 363     if (if_name != "port") {
 364         panic("PhysicalMemory::getPort: unknown port %s requested", if_name);
 365     }
 366
 367     if (idx >= (int)ports.size()) {
 368         ports.resize(idx + 1);
 369     }
 370
 371     if (ports[idx] != NULL) {
 372         panic("PhysicalMemory::getPort: port %d already assigned", idx);
 373     }
 374
 375     MemoryPort *port =
 376         new MemoryPort(csprintf("%s-port%d", name(), idx), this);
 377
 378     ports[idx] = port;
 379     return port;
 380 }
 381
 382
 383 void
 384 PhysicalMemory::recvStatusChange(Port::Status status)
 385 {
 386 }
 387
 388 PhysicalMemory::MemoryPort::MemoryPort(const std::string &_name,
 389                                        PhysicalMemory *_memory)
 390     : SimpleTimingPort(_name, _memory), memory(_memory)
 391 { }
 392
 393 void
 394 PhysicalMemory::MemoryPort::recvStatusChange(Port::Status status)
 395 {
 396     memory->recvStatusChange(status);
 397 }
 398
 399 void
 400 PhysicalMemory::MemoryPort::getDeviceAddressRanges(AddrRangeList &resp,
 401                                                    bool &snoop)
 402 {
 403     memory->getAddressRanges(resp, snoop);
 404 }
 405
 406 void
 407 PhysicalMemory::getAddressRanges(AddrRangeList &resp, bool &snoop)
 408 {
 409     snoop = false;
 410     resp.clear();
 411     resp.push_back(RangeSize(start(), params()->range.size()));
 412 }
 413
 414 unsigned
 415 PhysicalMemory::MemoryPort::deviceBlockSize() const
 416 {
 417     return memory->deviceBlockSize();
 418 }
 419
 420 Tick
 421 PhysicalMemory::MemoryPort::recvAtomic(PacketPtr pkt)
 422 {
 423     return memory->doAtomicAccess(pkt);
 424 }
 425
 426 void
 427 PhysicalMemory::MemoryPort::recvFunctional(PacketPtr pkt)
 428 {
 429     pkt->pushLabel(memory->name());
 430
 431     if (!checkFunctional(pkt)) {
 432         // Default implementation of SimpleTimingPort::recvFunctional()
 433         // calls recvAtomic() and throws away the latency; we can save a
 434         // little here by just not calculating the latency.
 435         memory->doFunctionalAccess(pkt);
 436     }
 437
 438     pkt->popLabel();
 439 }
 440
 441 unsigned int
 442 PhysicalMemory::drain(Event *de)
 443 {
 444     int count = 0;
 445     for (PortIterator pi = ports.begin(); pi != ports.end(); ++pi) {
 446         count += (*pi)->drain(de);
 447     }
 448
 449     if (count)
 450         changeState(Draining);
 451     else
 452         changeState(Drained);
 453     return count;
 454 }
 455
 456 void
 457 PhysicalMemory::serialize(ostream &os)
 458 {
 459     if (!pmemAddr)
 460         return;
 461
 462     gzFile compressedMem;
 463     string filename = name() + ".physmem";
 464
 465     SERIALIZE_SCALAR(filename);
 466
 467     // write memory file
 468     string thefile = Checkpoint::dir() + "/" + filename.c_str();
 469     int fd = creat(thefile.c_str(), 0664);
 470     if (fd < 0) {
 471         perror("creat");
 472         fatal("Can't open physical memory checkpoint file '%s'\n", filename);
 473     }
 474
 475     compressedMem = gzdopen(fd, "wb");
 476     if (compressedMem == NULL)
 477         fatal("Insufficient memory to allocate compression state for %s\n",
 478                 filename);
 479
 480     if (gzwrite(compressedMem, pmemAddr, params()->range.size()) !=
 481         (int)params()->range.size()) {
 482         fatal("Write failed on physical memory checkpoint file '%s'\n",
 483               filename);
 484     }
 485
 486     if (gzclose(compressedMem))
 487         fatal("Close failed on physical memory checkpoint file '%s'\n",
 488               filename);
 489 }
 490
 491 void
 492 PhysicalMemory::unserialize(Checkpoint *cp, const string &section)
 493 {
 494     if (!pmemAddr)
 495         return;
 496
 497     gzFile compressedMem;
 498     long *tempPage;
 499     long *pmem_current;
 500     uint64_t curSize;
 501     uint32_t bytesRead;
 502     const uint32_t chunkSize = 16384;
 503
 504     string filename;
 505
 506     UNSERIALIZE_SCALAR(filename);
 507
 508     filename = cp->cptDir + "/" + filename;
 509
 510     // mmap memoryfile
 511     int fd = open(filename.c_str(), O_RDONLY);
 512     if (fd < 0) {
 513         perror("open");
 514         fatal("Can't open physical memory checkpoint file '%s'", filename);
 515     }
 516
 517     compressedMem = gzdopen(fd, "rb");
 518     if (compressedMem == NULL)
 519         fatal("Insufficient memory to allocate compression state for %s\n",
 520                 filename);
 521
 522     // unmap file that was mmaped in the constructor
 523     // This is done here to make sure that gzip and open don't muck with our
 524     // nice large space of memory before we reallocate it
 525     munmap((char*)pmemAddr, params()->range.size());
 526
 527     pmemAddr = (uint8_t *)mmap(NULL, params()->range.size(),
 528         PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);
 529
 530     if (pmemAddr == (void *)MAP_FAILED) {
 531         perror("mmap");
 532         fatal("Could not mmap physical memory!\n");
 533     }
 534
 535     curSize = 0;
 536     tempPage = (long*)malloc(chunkSize);
 537     if (tempPage == NULL)
 538         fatal("Unable to malloc memory to read file %s\n", filename);
 539
 540     /* Only copy bytes that are non-zero, so we don't give the VM system hell */
 541     while (curSize < params()->range.size()) {
 542         bytesRead = gzread(compressedMem, tempPage, chunkSize);
 543         if (bytesRead == 0)
 544             break;
 545
 546         assert(bytesRead % sizeof(long) == 0);
 547
 548         for (uint32_t x = 0; x < bytesRead / sizeof(long); x++)
 549         {
 550              if (*(tempPage+x) != 0) {
 551                  pmem_current = (long*)(pmemAddr + curSize + x * sizeof(long));
 552                  *pmem_current = *(tempPage+x);
 553              }
 554         }
 555         curSize += bytesRead;
 556     }
 557
 558     free(tempPage);
 559
 560     if (gzclose(compressedMem))
 561         fatal("Close failed on physical memory checkpoint file '%s'\n",
 562               filename);
 563
 564 }
 565
 566 PhysicalMemory *
 567 PhysicalMemoryParams::create()
 568 {
 569     return new PhysicalMemory(this);
 570 }