src/arch/arm/linux/system.cc

   1 /*
   2  * Copyright (c) 2010-2013, 2016 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) 2002-2006 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
  41 #include "arch/arm/linux/system.hh"
  42
  43 #include "arch/arm/isa_traits.hh"
  44 #include "arch/arm/linux/atag.hh"
  45 #include "arch/arm/utility.hh"
  46 #include "arch/generic/linux/threadinfo.hh"
  47 #include "base/loader/dtb_file.hh"
  48 #include "base/loader/object_file.hh"
  49 #include "base/loader/symtab.hh"
  50 #include "cpu/base.hh"
  51 #include "cpu/pc_event.hh"
  52 #include "cpu/thread_context.hh"
  53 #include "debug/Loader.hh"
  54 #include "kern/linux/events.hh"
  55 #include "kern/linux/helpers.hh"
  56 #include "mem/fs_translating_port_proxy.hh"
  57 #include "mem/physical.hh"
  58 #include "sim/stat_control.hh"
  59
  60 using namespace ArmISA;
  61 using namespace Linux;
  62
  63 LinuxArmSystem::LinuxArmSystem(Params *p)
  64     : GenericArmSystem(p), dumpStatsPCEvent(nullptr),
  65       enableContextSwitchStatsDump(p->enable_context_switch_stats_dump),
  66       taskFile(nullptr), kernelPanicEvent(nullptr), kernelOopsEvent(nullptr)
  67 {
  68     const std::string dmesg_output = name() + ".dmesg";
  69     if (p->panic_on_panic) {
  70         kernelPanicEvent = addKernelFuncEventOrPanic<Linux::KernelPanicEvent>(
  71             "panic", "Kernel panic in simulated kernel", dmesg_output);
  72     } else {
  73         kernelPanicEvent = addKernelFuncEventOrPanic<Linux::DmesgDumpEvent>(
  74             "panic", "Kernel panic in simulated kernel", dmesg_output);
  75     }
  76
  77     if (p->panic_on_oops) {
  78         kernelOopsEvent = addKernelFuncEventOrPanic<Linux::KernelPanicEvent>(
  79             "oops_exit", "Kernel oops in guest", dmesg_output);
  80     } else {
  81         kernelOopsEvent = addKernelFuncEventOrPanic<Linux::DmesgDumpEvent>(
  82             "oops_exit", "Kernel oops in guest", dmesg_output);
  83     }
  84
  85     // With ARM udelay() is #defined to __udelay
  86     // newer kernels use __loop_udelay and __loop_const_udelay symbols
  87     uDelaySkipEvent = addKernelFuncEvent<UDelayEvent>(
  88         "__loop_udelay", "__udelay", 1000, 0);
  89     if (!uDelaySkipEvent)
  90         uDelaySkipEvent = addKernelFuncEventOrPanic<UDelayEvent>(
  91          "__udelay", "__udelay", 1000, 0);
  92
  93     // constant arguments to udelay() have some precomputation done ahead of
  94     // time. Constant comes from code.
  95     constUDelaySkipEvent = addKernelFuncEvent<UDelayEvent>(
  96         "__loop_const_udelay", "__const_udelay", 1000, 107374);
  97     if (!constUDelaySkipEvent)
  98         constUDelaySkipEvent = addKernelFuncEventOrPanic<UDelayEvent>(
  99          "__const_udelay", "__const_udelay", 1000, 107374);
 100
 101 }
 102
 103 void
 104 LinuxArmSystem::initState()
 105 {
 106     // Moved from the constructor to here since it relies on the
 107     // address map being resolved in the interconnect
 108
 109     // Call the initialisation of the super class
 110     GenericArmSystem::initState();
 111
 112     // Load symbols at physical address, we might not want
 113     // to do this permanently, for but early bootup work
 114     // it is helpful.
 115     if (params()->early_kernel_symbols) {
 116         kernel->loadGlobalSymbols(kernelSymtab, 0, 0, loadAddrMask);
 117         kernel->loadGlobalSymbols(debugSymbolTable, 0, 0, loadAddrMask);
 118     }
 119
 120     // Setup boot data structure
 121     Addr addr = 0;
 122     // Check if the kernel image has a symbol that tells us it supports
 123     // device trees.
 124     bool kernel_has_fdt_support =
 125         kernelSymtab->findAddress("unflatten_device_tree", addr);
 126     bool dtb_file_specified = params()->dtb_filename != "";
 127
 128     if (kernel_has_fdt_support && dtb_file_specified) {
 129         // Kernel supports flattened device tree and dtb file specified.
 130         // Using Device Tree Blob to describe system configuration.
 131         inform("Loading DTB file: %s at address %#x\n", params()->dtb_filename,
 132                 params()->atags_addr + loadAddrOffset);
 133
 134         DtbFile *dtb_file = new DtbFile(params()->dtb_filename);
 135
 136         if (!dtb_file->addBootCmdLine(params()->boot_osflags.c_str(),
 137                                       params()->boot_osflags.size())) {
 138             warn("couldn't append bootargs to DTB file: %s\n",
 139                  params()->dtb_filename);
 140         }
 141
 142         dtb_file->buildImage().
 143             offset(params()->atags_addr + loadAddrOffset).write(physProxy);
 144         delete dtb_file;
 145     } else {
 146         // Using ATAGS
 147         // Warn if the kernel supports FDT and we haven't specified one
 148         if (kernel_has_fdt_support) {
 149             assert(!dtb_file_specified);
 150             warn("Kernel supports device tree, but no DTB file specified\n");
 151         }
 152         // Warn if the kernel doesn't support FDT and we have specified one
 153         if (dtb_file_specified) {
 154             assert(!kernel_has_fdt_support);
 155             warn("DTB file specified, but no device tree support in kernel\n");
 156         }
 157
 158         AtagCore ac;
 159         ac.flags(1); // read-only
 160         ac.pagesize(8192);
 161         ac.rootdev(0);
 162
 163         AddrRangeList atagRanges = physmem.getConfAddrRanges();
 164         if (atagRanges.size() != 1) {
 165             fatal("Expected a single ATAG memory entry but got %d\n",
 166                   atagRanges.size());
 167         }
 168         AtagMem am;
 169         am.memSize(atagRanges.begin()->size());
 170         am.memStart(atagRanges.begin()->start());
 171
 172         AtagCmdline ad;
 173         ad.cmdline(params()->boot_osflags);
 174
 175         DPRINTF(Loader, "boot command line %d bytes: %s\n",
 176                 ad.size() <<2, params()->boot_osflags.c_str());
 177
 178         AtagNone an;
 179
 180         uint32_t size = ac.size() + am.size() + ad.size() + an.size();
 181         uint32_t offset = 0;
 182         uint8_t *boot_data = new uint8_t[size << 2];
 183
 184         offset += ac.copyOut(boot_data + offset);
 185         offset += am.copyOut(boot_data + offset);
 186         offset += ad.copyOut(boot_data + offset);
 187         offset += an.copyOut(boot_data + offset);
 188
 189         DPRINTF(Loader, "Boot atags was %d bytes in total\n", size << 2);
 190         DDUMP(Loader, boot_data, size << 2);
 191
 192         physProxy.writeBlob(params()->atags_addr + loadAddrOffset, boot_data,
 193                 size << 2);
 194
 195         delete[] boot_data;
 196     }
 197
 198     // Kernel boot requirements to set up r0, r1 and r2 in ARMv7
 199     for (int i = 0; i < threadContexts.size(); i++) {
 200         threadContexts[i]->setIntReg(0, 0);
 201         threadContexts[i]->setIntReg(1, params()->machine_type);
 202         threadContexts[i]->setIntReg(2, params()->atags_addr + loadAddrOffset);
 203     }
 204 }
 205
 206 LinuxArmSystem::~LinuxArmSystem()
 207 {
 208     if (uDelaySkipEvent)
 209         delete uDelaySkipEvent;
 210     if (constUDelaySkipEvent)
 211         delete constUDelaySkipEvent;
 212
 213     if (dumpStatsPCEvent)
 214         delete dumpStatsPCEvent;
 215 }
 216
 217 LinuxArmSystem *
 218 LinuxArmSystemParams::create()
 219 {
 220     return new LinuxArmSystem(this);
 221 }
 222
 223 void
 224 LinuxArmSystem::startup()
 225 {
 226     if (enableContextSwitchStatsDump) {
 227         if (!highestELIs64()) {
 228             dumpStatsPCEvent =
 229                 addKernelFuncEvent<DumpStatsPCEvent>("__switch_to");
 230         } else {
 231             dumpStatsPCEvent =
 232                 addKernelFuncEvent<DumpStatsPCEvent64>("__switch_to");
 233         }
 234
 235         if (!dumpStatsPCEvent)
 236            panic("dumpStatsPCEvent not created!");
 237
 238         std::string task_filename = "tasks.txt";
 239         taskFile = simout.create(name() + "." + task_filename);
 240
 241         for (const auto tc : threadContexts) {
 242             uint32_t pid = tc->getCpuPtr()->getPid();
 243             if (pid != BaseCPU::invldPid) {
 244                 mapPid(tc, pid);
 245                 tc->getCpuPtr()->taskId(taskMap[pid]);
 246             }
 247         }
 248     }
 249 }
 250
 251 void
 252 LinuxArmSystem::mapPid(ThreadContext *tc, uint32_t pid)
 253 {
 254     // Create a new unique identifier for this pid
 255     std::map<uint32_t, uint32_t>::iterator itr = taskMap.find(pid);
 256     if (itr == taskMap.end()) {
 257         uint32_t map_size = taskMap.size();
 258         if (map_size > ContextSwitchTaskId::MaxNormalTaskId + 1) {
 259             warn_once("Error out of identifiers for cache occupancy stats");
 260             taskMap[pid] = ContextSwitchTaskId::Unknown;
 261         } else {
 262             taskMap[pid] = map_size;
 263         }
 264     }
 265 }
 266
 267 void
 268 LinuxArmSystem::dumpDmesg()
 269 {
 270     Linux::dumpDmesg(getThreadContext(0), std::cout);
 271 }
 272
 273 /**
 274  * Extracts the information used by the DumpStatsPCEvent by reading the
 275  * thread_info pointer passed to __switch_to() in 32 bit ARM Linux
 276  *
 277  *  r0 = task_struct of the previously running process
 278  *  r1 = thread_info of the previously running process
 279  *  r2 = thread_info of the next process to run
 280  */
 281 void
 282 DumpStatsPCEvent::getTaskDetails(ThreadContext *tc, uint32_t &pid,
 283     uint32_t &tgid, std::string &next_task_str, int32_t &mm) {
 284
 285     Linux::ThreadInfo ti(tc);
 286     Addr task_descriptor = tc->readIntReg(2);
 287     pid = ti.curTaskPID(task_descriptor);
 288     tgid = ti.curTaskTGID(task_descriptor);
 289     next_task_str = ti.curTaskName(task_descriptor);
 290
 291     // Streamline treats pid == -1 as the kernel process.
 292     // Also pid == 0 implies idle process (except during Linux boot)
 293     mm = ti.curTaskMm(task_descriptor);
 294 }
 295
 296 /**
 297  * Extracts the information used by the DumpStatsPCEvent64 by reading the
 298  * task_struct pointer passed to __switch_to() in 64 bit ARM Linux
 299  *
 300  *  r0 = task_struct of the previously running process
 301  *  r1 = task_struct of next process to run
 302  */
 303 void
 304 DumpStatsPCEvent64::getTaskDetails(ThreadContext *tc, uint32_t &pid,
 305     uint32_t &tgid, std::string &next_task_str, int32_t &mm) {
 306
 307     Linux::ThreadInfo ti(tc);
 308     Addr task_struct = tc->readIntReg(1);
 309     pid = ti.curTaskPIDFromTaskStruct(task_struct);
 310     tgid = ti.curTaskTGIDFromTaskStruct(task_struct);
 311     next_task_str = ti.curTaskNameFromTaskStruct(task_struct);
 312
 313     // Streamline treats pid == -1 as the kernel process.
 314     // Also pid == 0 implies idle process (except during Linux boot)
 315     mm = ti.curTaskMmFromTaskStruct(task_struct);
 316 }
 317
 318 /** This function is called whenever the the kernel function
 319  *  "__switch_to" is called to change running tasks.
 320  */
 321 void
 322 DumpStatsPCEvent::process(ThreadContext *tc)
 323 {
 324     uint32_t pid = 0;
 325     uint32_t tgid = 0;
 326     std::string next_task_str;
 327     int32_t mm = 0;
 328
 329     getTaskDetails(tc, pid, tgid, next_task_str, mm);
 330
 331     bool is_kernel = (mm == 0);
 332     if (is_kernel && (pid != 0)) {
 333         pid = -1;
 334         tgid = -1;
 335         next_task_str = "kernel";
 336     }
 337
 338     LinuxArmSystem* sys = dynamic_cast<LinuxArmSystem *>(tc->getSystemPtr());
 339     if (!sys) {
 340         panic("System is not LinuxArmSystem while getting Linux process info!");
 341     }
 342     std::map<uint32_t, uint32_t>& taskMap = sys->taskMap;
 343
 344     // Create a new unique identifier for this pid
 345     sys->mapPid(tc, pid);
 346
 347     // Set cpu task id, output process info, and dump stats
 348     tc->getCpuPtr()->taskId(taskMap[pid]);
 349     tc->getCpuPtr()->setPid(pid);
 350
 351     OutputStream* taskFile = sys->taskFile;
 352
 353     // Task file is read by cache occupancy plotting script or
 354     // Streamline conversion script.
 355     ccprintf(*(taskFile->stream()),
 356              "tick=%lld %d cpu_id=%d next_pid=%d next_tgid=%d next_task=%s\n",
 357              curTick(), taskMap[pid], tc->cpuId(), (int) pid, (int) tgid,
 358              next_task_str);
 359     taskFile->stream()->flush();
 360
 361     // Dump and reset statistics
 362     Stats::schedStatEvent(true, true, curTick(), 0);
 363 }
 364