chrome/common/profiling.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/common/profiling.h"
   6
   7 #include "base/at_exit.h"
   8 #include "base/bind.h"
   9 #include "base/command_line.h"
  10 #include "base/debug/profiler.h"
  11 #include "base/lazy_instance.h"
  12 #include "base/message_loop/message_loop.h"
  13 #include "base/strings/string_util.h"
  14 #include "base/threading/thread.h"
  15 #include "chrome/common/chrome_switches.h"
  16 #include "gin/public/debug.h"
  17 #include "v8/include/v8.h"
  18
  19 namespace {
  20
  21 base::debug::AddDynamicSymbol add_dynamic_symbol_func = NULL;
  22 base::debug::MoveDynamicSymbol move_dynamic_symbol_func = NULL;
  23
  24 void JitCodeEventHandler(const v8::JitCodeEvent* event) {
  25   DCHECK_NE(static_cast<base::debug::AddDynamicSymbol>(NULL),
  26             add_dynamic_symbol_func);
  27   DCHECK_NE(static_cast<base::debug::MoveDynamicSymbol>(NULL),
  28             move_dynamic_symbol_func);
  29
  30   switch (event->type) {
  31     case v8::JitCodeEvent::CODE_ADDED:
  32       add_dynamic_symbol_func(event->code_start, event->code_len,
  33                               event->name.str, event->name.len);
  34       break;
  35
  36     case v8::JitCodeEvent::CODE_MOVED:
  37       move_dynamic_symbol_func(event->code_start, event->new_code_start);
  38       break;
  39
  40     default:
  41       break;
  42   }
  43 }
  44
  45 std::string GetProfileName() {
  46   static const char kDefaultProfileName[] = "chrome-profile-{type}-{pid}";
  47   CR_DEFINE_STATIC_LOCAL(std::string, profile_name, ());
  48
  49   if (profile_name.empty()) {
  50     const base::CommandLine& command_line =
  51         *base::CommandLine::ForCurrentProcess();
  52     if (command_line.HasSwitch(switches::kProfilingFile))
  53       profile_name = command_line.GetSwitchValueASCII(switches::kProfilingFile);
  54     else
  55       profile_name = std::string(kDefaultProfileName);
  56     std::string process_type =
  57         command_line.GetSwitchValueASCII(switches::kProcessType);
  58     std::string type = process_type.empty() ?
  59         std::string("browser") : std::string(process_type);
  60     ReplaceSubstringsAfterOffset(&profile_name, 0, "{type}", type.c_str());
  61   }
  62   return profile_name;
  63 }
  64
  65 void FlushProfilingData(base::Thread* thread) {
  66   static const int kProfilingFlushSeconds = 10;
  67
  68   if (!Profiling::BeingProfiled())
  69     return;
  70
  71   base::debug::FlushProfiling();
  72   static int flush_seconds;
  73   if (!flush_seconds) {
  74     const base::CommandLine& command_line =
  75         *base::CommandLine::ForCurrentProcess();
  76     std::string profiling_flush =
  77         command_line.GetSwitchValueASCII(switches::kProfilingFlush);
  78     if (!profiling_flush.empty()) {
  79       flush_seconds = atoi(profiling_flush.c_str());
  80       DCHECK(flush_seconds > 0);
  81     } else {
  82       flush_seconds = kProfilingFlushSeconds;
  83     }
  84   }
  85   thread->message_loop()->PostDelayedTask(
  86       FROM_HERE,
  87       base::Bind(&FlushProfilingData, thread),
  88       base::TimeDelta::FromSeconds(flush_seconds));
  89 }
  90
  91 class ProfilingThreadControl {
  92  public:
  93   ProfilingThreadControl() : thread_(NULL) {}
  94
  95   void Start() {
  96     base::AutoLock locked(lock_);
  97
  98     if (thread_ && thread_->IsRunning())
  99       return;
 100     thread_ = new base::Thread("Profiling_Flush");
 101     thread_->Start();
 102     thread_->message_loop()->PostTask(
 103         FROM_HERE, base::Bind(&FlushProfilingData, thread_));
 104   }
 105
 106   void Stop() {
 107     base::AutoLock locked(lock_);
 108
 109     if (!thread_ || !thread_->IsRunning())
 110       return;
 111     thread_->Stop();
 112     delete thread_;
 113     thread_ = NULL;
 114   }
 115
 116  private:
 117   base::Thread* thread_;
 118   base::Lock lock_;
 119
 120   DISALLOW_COPY_AND_ASSIGN(ProfilingThreadControl);
 121 };
 122
 123 base::LazyInstance<ProfilingThreadControl>::Leaky
 124     g_flush_thread_control = LAZY_INSTANCE_INITIALIZER;
 125
 126 } // namespace
 127
 128 // static
 129 void Profiling::ProcessStarted() {
 130   const base::CommandLine& command_line =
 131       *base::CommandLine::ForCurrentProcess();
 132   std::string process_type =
 133       command_line.GetSwitchValueASCII(switches::kProcessType);
 134
 135   // Establish the V8 profiling hooks if we're an instrumented binary.
 136   if (base::debug::IsBinaryInstrumented()) {
 137     base::debug::ReturnAddressLocationResolver resolve_func =
 138         base::debug::GetProfilerReturnAddrResolutionFunc();
 139
 140     if (resolve_func != NULL) {
 141       v8::V8::SetReturnAddressLocationResolver(resolve_func);
 142     }
 143
 144     // Set up the JIT code entry handler and the symbol callbacks if the
 145     // profiler supplies them.
 146     // TODO(siggi): Maybe add a switch or an environment variable to turn off
 147     //     V8 profiling?
 148     base::debug::DynamicFunctionEntryHook entry_hook_func =
 149         base::debug::GetProfilerDynamicFunctionEntryHookFunc();
 150     add_dynamic_symbol_func = base::debug::GetProfilerAddDynamicSymbolFunc();
 151     move_dynamic_symbol_func = base::debug::GetProfilerMoveDynamicSymbolFunc();
 152
 153     if (entry_hook_func != NULL &&
 154         add_dynamic_symbol_func != NULL &&
 155         move_dynamic_symbol_func != NULL) {
 156       gin::Debug::SetFunctionEntryHook(entry_hook_func);
 157       gin::Debug::SetJitCodeEventHandler(&JitCodeEventHandler);
 158     }
 159   }
 160
 161   if (command_line.HasSwitch(switches::kProfilingAtStart)) {
 162     std::string process_type_to_start =
 163         command_line.GetSwitchValueASCII(switches::kProfilingAtStart);
 164     if (process_type == process_type_to_start)
 165       Start();
 166   }
 167 }
 168
 169 // static
 170 void Profiling::Start() {
 171   const base::CommandLine& command_line =
 172       *base::CommandLine::ForCurrentProcess();
 173   bool flush = command_line.HasSwitch(switches::kProfilingFlush);
 174   base::debug::StartProfiling(GetProfileName());
 175
 176   // Schedule profile data flushing for single process because it doesn't
 177   // get written out correctly on exit.
 178   if (flush)
 179     g_flush_thread_control.Get().Start();
 180 }
 181
 182 // static
 183 void Profiling::Stop() {
 184   g_flush_thread_control.Get().Stop();
 185   base::debug::StopProfiling();
 186 }
 187
 188 // static
 189 bool Profiling::BeingProfiled() {
 190   return base::debug::BeingProfiled();
 191 }
 192
 193 // static
 194 void Profiling::Toggle() {
 195   if (BeingProfiled())
 196     Stop();
 197   else
 198     Start();
 199 }