optimizing-compile-dispatcher.cc 7.57 KB
Newer Older
1
// Copyright 2012 the V8 project authors. All rights reserved.
2 3
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
4

5
#include "src/compiler-dispatcher/optimizing-compile-dispatcher.h"
6

7
#include "src/base/atomicops.h"
8 9
#include "src/compilation-info.h"
#include "src/compiler.h"
10
#include "src/isolate.h"
11
#include "src/objects-inl.h"
12
#include "src/tracing/trace-event.h"
13
#include "src/v8.h"
14 15 16 17

namespace v8 {
namespace internal {

18 19
namespace {

20
void DisposeCompilationJob(CompilationJob* job, bool restore_function_code) {
21
  if (restore_function_code) {
22
    Handle<JSFunction> function = job->compilation_info()->closure();
23
    function->set_code(function->shared()->code());
24 25 26
    if (function->IsInOptimizationQueue()) {
      function->ClearOptimizationMarker();
    }
27 28
    // TODO(mvstanton): We can't call EnsureLiterals here due to allocation,
    // but we probably shouldn't call set_code either, as this
29 30
    // sometimes runs on the worker thread!
    // JSFunction::EnsureLiterals(function);
31
  }
32
  delete job;
33 34 35 36
}

}  // namespace

37
class OptimizingCompileDispatcher::CompileTask : public v8::Task {
38
 public:
39 40 41 42 43
  explicit CompileTask(Isolate* isolate,
                       OptimizingCompileDispatcher* dispatcher)
      : isolate_(isolate), dispatcher_(dispatcher) {
    base::LockGuard<base::Mutex> lock_guard(&dispatcher_->ref_count_mutex_);
    ++dispatcher_->ref_count_;
44
  }
45 46 47 48 49

  virtual ~CompileTask() {}

 private:
  // v8::Task overrides.
50
  void Run() override {
51 52 53 54
    DisallowHeapAllocation no_allocation;
    DisallowHandleAllocation no_handles;
    DisallowHandleDereference no_deref;

55 56
    {
      TimerEventScope<TimerEventRecompileConcurrent> timer(isolate_);
57 58 59

      TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
                   "V8.RecompileConcurrent");
60

61
      if (dispatcher_->recompilation_delay_ != 0) {
62
        base::OS::Sleep(base::TimeDelta::FromMilliseconds(
63
            dispatcher_->recompilation_delay_));
64
      }
65

66
      dispatcher_->CompileNext(dispatcher_->NextInput(true));
67
    }
68
    {
69 70 71
      base::LockGuard<base::Mutex> lock_guard(&dispatcher_->ref_count_mutex_);
      if (--dispatcher_->ref_count_ == 0) {
        dispatcher_->ref_count_zero_.NotifyOne();
72
      }
73 74 75 76
    }
  }

  Isolate* isolate_;
77
  OptimizingCompileDispatcher* dispatcher_;
78 79 80 81

  DISALLOW_COPY_AND_ASSIGN(CompileTask);
};

82
OptimizingCompileDispatcher::~OptimizingCompileDispatcher() {
83 84 85 86
#ifdef DEBUG
  {
    base::LockGuard<base::Mutex> lock_guard(&ref_count_mutex_);
    DCHECK_EQ(0, ref_count_);
87
  }
88
#endif
89
  DCHECK_EQ(0, input_queue_length_);
90 91 92
  DeleteArray(input_queue_);
}

93
CompilationJob* OptimizingCompileDispatcher::NextInput(bool check_if_flushing) {
94
  base::LockGuard<base::Mutex> access_input_queue_(&input_queue_mutex_);
95
  if (input_queue_length_ == 0) return nullptr;
96
  CompilationJob* job = input_queue_[InputQueueIndex(0)];
97
  DCHECK_NOT_NULL(job);
98 99
  input_queue_shift_ = InputQueueIndex(1);
  input_queue_length_--;
100
  if (check_if_flushing) {
101
    if (static_cast<ModeFlag>(base::Acquire_Load(&mode_)) == FLUSH) {
102
      AllowHandleDereference allow_handle_dereference;
103
      DisposeCompilationJob(job, true);
104
      return nullptr;
105
    }
106
  }
107 108 109
  return job;
}

110
void OptimizingCompileDispatcher::CompileNext(CompilationJob* job) {
111
  if (!job) return;
112

113
  // The function may have already been optimized by OSR.  Simply continue.
114
  CompilationJob::Status status = job->ExecuteJob();
115
  USE(status);  // Prevent an unused-variable error.
116

117
  // The function may have already been optimized by OSR.  Simply continue.
118 119
  // Use a mutex to make sure that functions marked for install
  // are always also queued.
120 121
  base::LockGuard<base::Mutex> access_output_queue_(&output_queue_mutex_);
  output_queue_.push(job);
122 123 124
  isolate_->stack_guard()->RequestInstallCode();
}

125 126
void OptimizingCompileDispatcher::FlushOutputQueue(bool restore_function_code) {
  for (;;) {
127
    CompilationJob* job = nullptr;
128 129 130 131 132
    {
      base::LockGuard<base::Mutex> access_output_queue_(&output_queue_mutex_);
      if (output_queue_.empty()) return;
      job = output_queue_.front();
      output_queue_.pop();
133
    }
134

135
    DisposeCompilationJob(job, restore_function_code);
136
  }
137
}
138

139 140
void OptimizingCompileDispatcher::Flush(BlockingBehavior blocking_behavior) {
  if (blocking_behavior == BlockingBehavior::kDontBlock) {
141
    if (FLAG_block_concurrent_recompilation) Unblock();
142 143 144 145 146 147 148 149 150 151 152 153 154 155
    base::LockGuard<base::Mutex> access_input_queue_(&input_queue_mutex_);
    while (input_queue_length_ > 0) {
      CompilationJob* job = input_queue_[InputQueueIndex(0)];
      DCHECK_NOT_NULL(job);
      input_queue_shift_ = InputQueueIndex(1);
      input_queue_length_--;
      DisposeCompilationJob(job, true);
    }
    FlushOutputQueue(true);
    if (FLAG_trace_concurrent_recompilation) {
      PrintF("  ** Flushed concurrent recompilation queues (not blocking).\n");
    }
    return;
  }
156
  base::Release_Store(&mode_, static_cast<base::AtomicWord>(FLUSH));
157
  if (FLAG_block_concurrent_recompilation) Unblock();
158
  {
159 160
    base::LockGuard<base::Mutex> lock_guard(&ref_count_mutex_);
    while (ref_count_ > 0) ref_count_zero_.Wait(&ref_count_mutex_);
161
    base::Release_Store(&mode_, static_cast<base::AtomicWord>(COMPILE));
162
  }
163
  FlushOutputQueue(true);
164
  if (FLAG_trace_concurrent_recompilation) {
165 166
    PrintF("  ** Flushed concurrent recompilation queues.\n");
  }
167 168
}

169 170
void OptimizingCompileDispatcher::Stop() {
  base::Release_Store(&mode_, static_cast<base::AtomicWord>(FLUSH));
171
  if (FLAG_block_concurrent_recompilation) Unblock();
172
  {
173 174
    base::LockGuard<base::Mutex> lock_guard(&ref_count_mutex_);
    while (ref_count_ > 0) ref_count_zero_.Wait(&ref_count_mutex_);
175
    base::Release_Store(&mode_, static_cast<base::AtomicWord>(COMPILE));
176 177 178
  }

  if (recompilation_delay_ != 0) {
179 180
    // At this point the optimizing compiler thread's event loop has stopped.
    // There is no need for a mutex when reading input_queue_length_.
181
    while (input_queue_length_ > 0) CompileNext(NextInput());
182 183
    InstallOptimizedFunctions();
  } else {
184
    FlushOutputQueue(false);
185
  }
186 187
}

188
void OptimizingCompileDispatcher::InstallOptimizedFunctions() {
189
  HandleScope handle_scope(isolate_);
190

191
  for (;;) {
192
    CompilationJob* job = nullptr;
193 194 195 196 197 198
    {
      base::LockGuard<base::Mutex> access_output_queue_(&output_queue_mutex_);
      if (output_queue_.empty()) return;
      job = output_queue_.front();
      output_queue_.pop();
    }
199
    CompilationInfo* info = job->compilation_info();
200
    Handle<JSFunction> function(*info->closure());
201
    if (function->HasOptimizedCode()) {
202 203
      if (FLAG_trace_concurrent_recompilation) {
        PrintF("  ** Aborting compilation for ");
204
        function->ShortPrint();
205
        PrintF(" as it has already been optimized.\n");
206
      }
207
      DisposeCompilationJob(job, false);
208
    } else {
209
      Compiler::FinalizeCompilationJob(job);
210
    }
211
  }
212 213
}

214
void OptimizingCompileDispatcher::QueueForOptimization(CompilationJob* job) {
215
  DCHECK(IsQueueAvailable());
216
  {
217
    // Add job to the back of the input queue.
218
    base::LockGuard<base::Mutex> access_input_queue(&input_queue_mutex_);
219
    DCHECK_LT(input_queue_length_, input_queue_capacity_);
220 221
    input_queue_[InputQueueIndex(input_queue_length_)] = job;
    input_queue_length_++;
222
  }
223
  if (FLAG_block_concurrent_recompilation) {
224
    blocked_jobs_++;
225
  } else {
226
    V8::GetCurrentPlatform()->CallOnBackgroundThread(
227
        new CompileTask(isolate_, this), v8::Platform::kShortRunningTask);
228 229 230
  }
}

231
void OptimizingCompileDispatcher::Unblock() {
232
  while (blocked_jobs_ > 0) {
233
    V8::GetCurrentPlatform()->CallOnBackgroundThread(
234
        new CompileTask(isolate_, this), v8::Platform::kShortRunningTask);
235 236
    blocked_jobs_--;
  }
237 238
}

239 240
}  // namespace internal
}  // namespace v8