bytecode/SamplingTool.cpp

   1 /*
   2  * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  * 1.  Redistributions of source code must retain the above copyright
   9  *     notice, this list of conditions and the following disclaimer.
  10  * 2.  Redistributions in binary form must reproduce the above copyright
  11  *     notice, this list of conditions and the following disclaimer in the
  12  *     documentation and/or other materials provided with the distribution.
  13  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
  14  *     its contributors may be used to endorse or promote products derived
  15  *     from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  20  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  21  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  23  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  24  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include "config.h"
  30 #include "SamplingTool.h"
  31
  32 #include "CodeBlock.h"
  33 #include "Interpreter.h"
  34 #include "Opcode.h"
  35
  36 #if !OS(WINDOWS)
  37 #include <unistd.h>
  38 #endif
  39
  40 namespace JSC {
  41
  42 #if ENABLE(SAMPLING_FLAGS)
  43
  44 void SamplingFlags::sample()
  45 {
  46     uint32_t mask = 1 << 31;
  47     unsigned index;
  48
  49     for (index = 0; index < 32; ++index) {
  50         if (mask & s_flags)
  51             break;
  52         mask >>= 1;
  53     }
  54
  55     s_flagCounts[32 - index]++;
  56 }
  57
  58 void SamplingFlags::start()
  59 {
  60     for (unsigned i = 0; i <= 32; ++i)
  61         s_flagCounts[i] = 0;
  62 }
  63 void SamplingFlags::stop()
  64 {
  65     uint64_t total = 0;
  66     for (unsigned i = 0; i <= 32; ++i)
  67         total += s_flagCounts[i];
  68
  69     if (total) {
  70         printf("\nSamplingFlags: sample counts with flags set: (%lld total)\n", total);
  71         for (unsigned i = 0; i <= 32; ++i) {
  72             if (s_flagCounts[i])
  73                 printf("  [ %02d ] : %lld\t\t(%03.2f%%)\n", i, s_flagCounts[i], (100.0 * s_flagCounts[i]) / total);
  74         }
  75         printf("\n");
  76     } else
  77     printf("\nSamplingFlags: no samples.\n\n");
  78 }
  79 uint64_t SamplingFlags::s_flagCounts[33];
  80
  81 #else
  82 void SamplingFlags::start() {}
  83 void SamplingFlags::stop() {}
  84 #endif
  85
  86 /*
  87   Start with flag 16 set.
  88   By doing this the monitoring of lower valued flags will be masked out
  89   until flag 16 is explictly cleared.
  90 */
  91 uint32_t SamplingFlags::s_flags = 1 << 15;
  92
  93
  94 #if OS(WINDOWS)
  95
  96 static void sleepForMicroseconds(unsigned us)
  97 {
  98     unsigned ms = us / 1000;
  99     if (us && !ms)
 100         ms = 1;
 101     Sleep(ms);
 102 }
 103
 104 #else
 105
 106 static void sleepForMicroseconds(unsigned us)
 107 {
 108     usleep(us);
 109 }
 110
 111 #endif
 112
 113 static inline unsigned hertz2us(unsigned hertz)
 114 {
 115     return 1000000 / hertz;
 116 }
 117
 118
 119 SamplingTool* SamplingTool::s_samplingTool = 0;
 120
 121
 122 bool SamplingThread::s_running = false;
 123 unsigned SamplingThread::s_hertz = 10000;
 124 ThreadIdentifier SamplingThread::s_samplingThread;
 125
 126 void* SamplingThread::threadStartFunc(void*)
 127 {
 128     while (s_running) {
 129         sleepForMicroseconds(hertz2us(s_hertz));
 130
 131 #if ENABLE(SAMPLING_FLAGS)
 132         SamplingFlags::sample();
 133 #endif
 134 #if ENABLE(OPCODE_SAMPLING)
 135         SamplingTool::sample();
 136 #endif
 137     }
 138
 139     return 0;
 140 }
 141
 142
 143 void SamplingThread::start(unsigned hertz)
 144 {
 145     ASSERT(!s_running);
 146     s_running = true;
 147     s_hertz = hertz;
 148
 149     s_samplingThread = createThread(threadStartFunc, 0, "JavaScriptCore::Sampler");
 150 }
 151
 152 void SamplingThread::stop()
 153 {
 154     ASSERT(s_running);
 155     s_running = false;
 156     waitForThreadCompletion(s_samplingThread, 0);
 157 }
 158
 159
 160 void ScriptSampleRecord::sample(CodeBlock* codeBlock, Instruction* vPC)
 161 {
 162     if (!m_samples) {
 163         m_size = codeBlock->instructions().size();
 164         m_samples = static_cast<int*>(calloc(m_size, sizeof(int)));
 165         m_codeBlock = codeBlock;
 166     }
 167
 168     ++m_sampleCount;
 169
 170     unsigned offest = vPC - codeBlock->instructions().begin();
 171     // Since we don't read and write codeBlock and vPC atomically, this check
 172     // can fail if we sample mid op_call / op_ret.
 173     if (offest < m_size) {
 174         m_samples[offest]++;
 175         m_opcodeSampleCount++;
 176     }
 177 }
 178
 179 void SamplingTool::doRun()
 180 {
 181     Sample sample(m_sample, m_codeBlock);
 182     ++m_sampleCount;
 183
 184     if (sample.isNull())
 185         return;
 186
 187     if (!sample.inHostFunction()) {
 188         unsigned opcodeID = m_interpreter->getOpcodeID(sample.vPC()[0].u.opcode);
 189
 190         ++m_opcodeSampleCount;
 191         ++m_opcodeSamples[opcodeID];
 192
 193         if (sample.inCTIFunction())
 194             m_opcodeSamplesInCTIFunctions[opcodeID]++;
 195     }
 196
 197 #if ENABLE(CODEBLOCK_SAMPLING)
 198     if (CodeBlock* codeBlock = sample.codeBlock()) {
 199         MutexLocker locker(m_scriptSampleMapMutex);
 200         ScriptSampleRecord* record = m_scopeSampleMap->get(codeBlock->ownerExecutable());
 201         ASSERT(record);
 202         record->sample(codeBlock, sample.vPC());
 203     }
 204 #endif
 205 }
 206
 207 void SamplingTool::sample()
 208 {
 209     s_samplingTool->doRun();
 210 }
 211
 212 void SamplingTool::notifyOfScope(ScriptExecutable* script)
 213 {
 214 #if ENABLE(CODEBLOCK_SAMPLING)
 215     MutexLocker locker(m_scriptSampleMapMutex);
 216     m_scopeSampleMap->set(script, new ScriptSampleRecord(script));
 217 #else
 218     UNUSED_PARAM(script);
 219 #endif
 220 }
 221
 222 void SamplingTool::setup()
 223 {
 224     s_samplingTool = this;
 225 }
 226
 227 #if ENABLE(OPCODE_SAMPLING)
 228
 229 struct OpcodeSampleInfo {
 230     OpcodeID opcode;
 231     long long count;
 232     long long countInCTIFunctions;
 233 };
 234
 235 struct LineCountInfo {
 236     unsigned line;
 237     unsigned count;
 238 };
 239
 240 static int compareOpcodeIndicesSampling(const void* left, const void* right)
 241 {
 242     const OpcodeSampleInfo* leftSampleInfo = reinterpret_cast<const OpcodeSampleInfo*>(left);
 243     const OpcodeSampleInfo* rightSampleInfo = reinterpret_cast<const OpcodeSampleInfo*>(right);
 244
 245     return (leftSampleInfo->count < rightSampleInfo->count) ? 1 : (leftSampleInfo->count > rightSampleInfo->count) ? -1 : 0;
 246 }
 247
 248 #if ENABLE(CODEBLOCK_SAMPLING)
 249 static int compareLineCountInfoSampling(const void* left, const void* right)
 250 {
 251     const LineCountInfo* leftLineCount = reinterpret_cast<const LineCountInfo*>(left);
 252     const LineCountInfo* rightLineCount = reinterpret_cast<const LineCountInfo*>(right);
 253
 254     return (leftLineCount->line > rightLineCount->line) ? 1 : (leftLineCount->line < rightLineCount->line) ? -1 : 0;
 255 }
 256
 257 static int compareScriptSampleRecords(const void* left, const void* right)
 258 {
 259     const ScriptSampleRecord* const leftValue = *static_cast<const ScriptSampleRecord* const *>(left);
 260     const ScriptSampleRecord* const rightValue = *static_cast<const ScriptSampleRecord* const *>(right);
 261
 262     return (leftValue->m_sampleCount < rightValue->m_sampleCount) ? 1 : (leftValue->m_sampleCount > rightValue->m_sampleCount) ? -1 : 0;
 263 }
 264 #endif
 265
 266 void SamplingTool::dump(ExecState* exec)
 267 {
 268     // Tidies up SunSpider output by removing short scripts - such a small number of samples would likely not be useful anyhow.
 269     if (m_sampleCount < 10)
 270         return;
 271
 272     // (1) Build and sort 'opcodeSampleInfo' array.
 273
 274     OpcodeSampleInfo opcodeSampleInfo[numOpcodeIDs];
 275     for (int i = 0; i < numOpcodeIDs; ++i) {
 276         opcodeSampleInfo[i].opcode = static_cast<OpcodeID>(i);
 277         opcodeSampleInfo[i].count = m_opcodeSamples[i];
 278         opcodeSampleInfo[i].countInCTIFunctions = m_opcodeSamplesInCTIFunctions[i];
 279     }
 280
 281     qsort(opcodeSampleInfo, numOpcodeIDs, sizeof(OpcodeSampleInfo), compareOpcodeIndicesSampling);
 282
 283     // (2) Print Opcode sampling results.
 284
 285     printf("\nBytecode samples [*]\n");
 286     printf("                             sample   %% of       %% of     |   cti     cti %%\n");
 287     printf("opcode                       count     VM        total    |  count   of self\n");
 288     printf("-------------------------------------------------------   |  ----------------\n");
 289
 290     for (int i = 0; i < numOpcodeIDs; ++i) {
 291         long long count = opcodeSampleInfo[i].count;
 292         if (!count)
 293             continue;
 294
 295         OpcodeID opcodeID = opcodeSampleInfo[i].opcode;
 296
 297         const char* opcodeName = opcodeNames[opcodeID];
 298         const char* opcodePadding = padOpcodeName(opcodeID, 28);
 299         double percentOfVM = (static_cast<double>(count) * 100) / m_opcodeSampleCount;
 300         double percentOfTotal = (static_cast<double>(count) * 100) / m_sampleCount;
 301         long long countInCTIFunctions = opcodeSampleInfo[i].countInCTIFunctions;
 302         double percentInCTIFunctions = (static_cast<double>(countInCTIFunctions) * 100) / count;
 303         fprintf(stdout, "%s:%s%-6lld %.3f%%\t%.3f%%\t  |   %-6lld %.3f%%\n", opcodeName, opcodePadding, count, percentOfVM, percentOfTotal, countInCTIFunctions, percentInCTIFunctions);
 304     }
 305
 306     printf("\n[*] Samples inside host code are not charged to any Bytecode.\n\n");
 307     printf("\tSamples inside VM:\t\t%lld / %lld (%.3f%%)\n", m_opcodeSampleCount, m_sampleCount, (static_cast<double>(m_opcodeSampleCount) * 100) / m_sampleCount);
 308     printf("\tSamples inside host code:\t%lld / %lld (%.3f%%)\n\n", m_sampleCount - m_opcodeSampleCount, m_sampleCount, (static_cast<double>(m_sampleCount - m_opcodeSampleCount) * 100) / m_sampleCount);
 309     printf("\tsample count:\tsamples inside this opcode\n");
 310     printf("\t%% of VM:\tsample count / all opcode samples\n");
 311     printf("\t%% of total:\tsample count / all samples\n");
 312     printf("\t--------------\n");
 313     printf("\tcti count:\tsamples inside a CTI function called by this opcode\n");
 314     printf("\tcti %% of self:\tcti count / sample count\n");
 315
 316 #if ENABLE(CODEBLOCK_SAMPLING)
 317
 318     // (3) Build and sort 'codeBlockSamples' array.
 319
 320     int scopeCount = m_scopeSampleMap->size();
 321     Vector<ScriptSampleRecord*> codeBlockSamples(scopeCount);
 322     ScriptSampleRecordMap::iterator iter = m_scopeSampleMap->begin();
 323     for (int i = 0; i < scopeCount; ++i, ++iter)
 324         codeBlockSamples[i] = iter->second;
 325
 326     qsort(codeBlockSamples.begin(), scopeCount, sizeof(ScriptSampleRecord*), compareScriptSampleRecords);
 327
 328     // (4) Print data from 'codeBlockSamples' array.
 329
 330     printf("\nCodeBlock samples\n\n");
 331
 332     for (int i = 0; i < scopeCount; ++i) {
 333         ScriptSampleRecord* record = codeBlockSamples[i];
 334         CodeBlock* codeBlock = record->m_codeBlock;
 335
 336         double blockPercent = (record->m_sampleCount * 100.0) / m_sampleCount;
 337
 338         if (blockPercent >= 1) {
 339             //Instruction* code = codeBlock->instructions().begin();
 340             printf("#%d: %s:%d: %d / %lld (%.3f%%)\n", i + 1, record->m_executable->sourceURL().UTF8String().c_str(), codeBlock->lineNumberForBytecodeOffset(exec, 0), record->m_sampleCount, m_sampleCount, blockPercent);
 341             if (i < 10) {
 342                 HashMap<unsigned,unsigned> lineCounts;
 343                 codeBlock->dump(exec);
 344
 345                 printf("    Opcode and line number samples [*]\n\n");
 346                 for (unsigned op = 0; op < record->m_size; ++op) {
 347                     int count = record->m_samples[op];
 348                     if (count) {
 349                         printf("    [% 4d] has sample count: % 4d\n", op, count);
 350                         unsigned line = codeBlock->lineNumberForBytecodeOffset(exec, op);
 351                         lineCounts.set(line, (lineCounts.contains(line) ? lineCounts.get(line) : 0) + count);
 352                     }
 353                 }
 354                 printf("\n");
 355
 356                 int linesCount = lineCounts.size();
 357                 Vector<LineCountInfo> lineCountInfo(linesCount);
 358                 int lineno = 0;
 359                 for (HashMap<unsigned,unsigned>::iterator iter = lineCounts.begin(); iter != lineCounts.end(); ++iter, ++lineno) {
 360                     lineCountInfo[lineno].line = iter->first;
 361                     lineCountInfo[lineno].count = iter->second;
 362                 }
 363
 364                 qsort(lineCountInfo.begin(), linesCount, sizeof(LineCountInfo), compareLineCountInfoSampling);
 365
 366                 for (lineno = 0; lineno < linesCount; ++lineno) {
 367                     printf("    Line #%d has sample count %d.\n", lineCountInfo[lineno].line, lineCountInfo[lineno].count);
 368                 }
 369                 printf("\n");
 370                 printf("    [*] Samples inside host code are charged to the calling Bytecode.\n");
 371                 printf("        Samples on a call / return boundary are not charged to a specific opcode or line.\n\n");
 372                 printf("            Samples on a call / return boundary: %d / %d (%.3f%%)\n\n", record->m_sampleCount - record->m_opcodeSampleCount, record->m_sampleCount, (static_cast<double>(record->m_sampleCount - record->m_opcodeSampleCount) * 100) / record->m_sampleCount);
 373             }
 374         }
 375     }
 376 #else
 377     UNUSED_PARAM(exec);
 378 #endif
 379 }
 380
 381 #else
 382
 383 void SamplingTool::dump(ExecState*)
 384 {
 385 }
 386
 387 #endif
 388
 389 void AbstractSamplingCounter::dump()
 390 {
 391 #if ENABLE(SAMPLING_COUNTERS)
 392     if (s_abstractSamplingCounterChain != &s_abstractSamplingCounterChainEnd) {
 393         printf("\nSampling Counter Values:\n");
 394         for (AbstractSamplingCounter* currCounter = s_abstractSamplingCounterChain; (currCounter != &s_abstractSamplingCounterChainEnd); currCounter = currCounter->m_next)
 395             printf("\t%s\t: %lld\n", currCounter->m_name, currCounter->m_counter);
 396         printf("\n\n");
 397     }
 398     s_completed = true;
 399 #endif
 400 }
 401
 402 AbstractSamplingCounter AbstractSamplingCounter::s_abstractSamplingCounterChainEnd;
 403 AbstractSamplingCounter* AbstractSamplingCounter::s_abstractSamplingCounterChain = &s_abstractSamplingCounterChainEnd;
 404 bool AbstractSamplingCounter::s_completed = false;
 405
 406 } // namespace JSC