The Tor Browser: tools/profiler/platform.h@97036ab72558 (annotated)

tools/profiler/platform.h@97036ab72558 (annotated)

tools/profiler/platform.h

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 // Copyright (c) 2006-2011 The Chromium Authors. All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions
 // are met:
 //  * Redistributions of source code must retain the above copyright
 //    notice, this list of conditions and the following disclaimer.
 //  * Redistributions in binary form must reproduce the above copyright
 //    notice, this list of conditions and the following disclaimer in
 //    the documentation and/or other materials provided with the
 //    distribution.
 //  * Neither the name of Google, Inc. nor the names of its contributors
 //    may be used to endorse or promote products derived from this
 //    software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 // FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 // COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 // INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 // BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 // OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 // AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 // OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 // SUCH DAMAGE.
 #ifndef TOOLS_PLATFORM_H_
 #define TOOLS_PLATFORM_H_
 #ifdef ANDROID
 #include <android/log.h>
 #else
 #define __android_log_print(a, ...)
 #endif
 #ifdef XP_UNIX
 #include <pthread.h>
 #endif
 #include <stdint.h>
 #include <math.h>
 #include "mozilla/unused.h"
 #include "mozilla/TimeStamp.h"
 #include "mozilla/Mutex.h"
 #include "MainThreadUtils.h"
 #include "PlatformMacros.h"
 #include "v8-support.h"
 #include <vector>
 #ifdef XP_WIN
 #include <windows.h>
 #endif
 #define ASSERT(a) MOZ_ASSERT(a)
 bool moz_profiler_verbose();
 #ifdef ANDROID
 # if defined(__arm__) || defined(__thumb__)
 #  define ENABLE_SPS_LEAF_DATA
 #  define ENABLE_ARM_LR_SAVING
 # endif
 # define LOG(text) \
     do { if (moz_profiler_verbose()) \
            __android_log_write(ANDROID_LOG_ERROR, "Profiler", text); \
     } while (0)
 # define LOGF(format, ...) \
     do { if (moz_profiler_verbose()) \
            __android_log_print(ANDROID_LOG_ERROR, "Profiler", format, \
                                __VA_ARGS__); \
     } while (0)
 #else
 # define LOG(text) \
     do { if (moz_profiler_verbose()) fprintf(stderr, "Profiler: %s\n", text); \
     } while (0)
 # define LOGF(format, ...) \
     do { if (moz_profiler_verbose()) fprintf(stderr, "Profiler: " format \
                                              "\n", __VA_ARGS__);        \
     } while (0)
 #endif
 #if defined(XP_MACOSX) || defined(XP_WIN) || defined(XP_LINUX)
 #define ENABLE_SPS_LEAF_DATA
 #endif
 extern mozilla::TimeStamp sStartTime;
 typedef uint8_t* Address;
 // ----------------------------------------------------------------------------
 // Mutex
 //
 // Mutexes are used for serializing access to non-reentrant sections of code.
 // The implementations of mutex should allow for nested/recursive locking.
 class Mutex {
  public:
   virtual ~Mutex() {}
   // Locks the given mutex. If the mutex is currently unlocked, it becomes
   // locked and owned by the calling thread, and immediately. If the mutex
   // is already locked by another thread, suspends the calling thread until
   // the mutex is unlocked.
   virtual int Lock() = 0;
   // Unlocks the given mutex. The mutex is assumed to be locked and owned by
   // the calling thread on entrance.
   virtual int Unlock() = 0;
   // Tries to lock the given mutex. Returns whether the mutex was
   // successfully locked.
   virtual bool TryLock() = 0;
 };
 // ----------------------------------------------------------------------------
 // OS
 //
 // This class has static methods for the different platform specific
 // functions. Add methods here to cope with differences between the
 // supported platforms.
 class OS {
  public:
   // Sleep for a number of milliseconds.
   static void Sleep(const int milliseconds);
   // Sleep for a number of microseconds.
   static void SleepMicro(const int microseconds);
   // Called on startup to initialize platform specific things
   static void Startup();
  private:
   static const int msPerSecond = 1000;
 };
 // ----------------------------------------------------------------------------
 // Thread
 //
 // Thread objects are used for creating and running threads. When the start()
 // method is called the new thread starts running the run() method in the new
 // thread. The Thread object should not be deallocated before the thread has
 // terminated.
 class Thread {
  public:
   // Create new thread.
   explicit Thread(const char* name);
   virtual ~Thread();
   // Start new thread by calling the Run() method in the new thread.
   void Start();
   void Join();
   inline const char* name() const {
     return name_;
   }
   // Abstract method for run handler.
   virtual void Run() = 0;
   // The thread name length is limited to 16 based on Linux's implementation of
   // prctl().
   static const int kMaxThreadNameLength = 16;
 #ifdef XP_WIN
   HANDLE thread_;
   typedef DWORD tid_t;
   tid_t thread_id_;
 #else
   typedef ::pid_t tid_t;
 #endif
 #if defined(XP_MACOSX)
   pthread_t thread_;
 #endif
   static tid_t GetCurrentId();
  private:
   void set_name(const char *name);
   char name_[kMaxThreadNameLength];
   int stack_size_;
   DISALLOW_COPY_AND_ASSIGN(Thread);
 };
 // ----------------------------------------------------------------------------
 // HAVE_NATIVE_UNWIND
 //
 // Pseudo backtraces are available on all platforms.  Native
 // backtraces are available only on selected platforms.  Breakpad is
 // the only supported native unwinder.  HAVE_NATIVE_UNWIND is set at
 // build time to indicate whether native unwinding is possible on this
 // platform.  The actual unwind mode currently in use is stored in
 // sUnwindMode.
 #undef HAVE_NATIVE_UNWIND
 #if defined(MOZ_PROFILING) \
     && (defined(SPS_PLAT_amd64_linux) || defined(SPS_PLAT_arm_android) \
         || defined(SPS_PLAT_x86_linux) \
         || defined(SPS_OS_windows) \
         || defined(SPS_OS_darwin))
 # define HAVE_NATIVE_UNWIND
 #endif
 /* Some values extracted at startup from environment variables, that
    control the behaviour of the breakpad unwinder. */
 extern const char* PROFILER_MODE;
 extern const char* PROFILER_INTERVAL;
 extern const char* PROFILER_ENTRIES;
 extern const char* PROFILER_STACK;
 extern const char* PROFILER_FEATURES;
 void read_profiler_env_vars();
 void profiler_usage();
 // Helper methods to expose modifying profiler behavior
 bool set_profiler_mode(const char*);
 bool set_profiler_interval(const char*);
 bool set_profiler_entries(const char*);
 bool set_profiler_scan(const char*);
 bool is_native_unwinding_avail();
 typedef  enum { UnwINVALID, UnwNATIVE, UnwPSEUDO, UnwCOMBINED }  UnwMode;
 extern UnwMode sUnwindMode;       /* what mode? */
 extern int     sUnwindInterval;   /* in milliseconds */
 extern int     sUnwindStackScan;  /* max # of dubious frames allowed */
 extern int     sProfileEntries;   /* how many entries do we store? */
 void set_tls_stack_top(void* stackTop);
 // ----------------------------------------------------------------------------
 // Sampler
 //
 // A sampler periodically samples the state of the VM and optionally
 // (if used for profiling) the program counter and stack pointer for
 // the thread that created it.
 class PseudoStack;
 class ThreadProfile;
 // TickSample captures the information collected for each sample.
 class TickSample {
  public:
   TickSample()
       :
         pc(NULL),
         sp(NULL),
         fp(NULL),
 #ifdef ENABLE_ARM_LR_SAVING
         lr(NULL),
 #endif
         context(NULL),
         isSamplingCurrentThread(false) {}
   void PopulateContext(void* aContext);
   Address pc;  // Instruction pointer.
   Address sp;  // Stack pointer.
   Address fp;  // Frame pointer.
 #ifdef ENABLE_ARM_LR_SAVING
   Address lr;  // ARM link register
 #endif
   void*   context;   // The context from the signal handler, if available. On
                      // Win32 this may contain the windows thread context.
   bool    isSamplingCurrentThread;
   ThreadProfile* threadProfile;
   mozilla::TimeStamp timestamp;
 };
 class ThreadInfo;
 class PlatformData;
 class TableTicker;
 class SyncProfile;
 class Sampler {
  public:
   // Initialize sampler.
   explicit Sampler(double interval, bool profiling, int entrySize);
   virtual ~Sampler();
   double interval() const { return interval_; }
   // This method is called for each sampling period with the current
   // program counter.
   virtual void Tick(TickSample* sample) = 0;
   // Immediately captures the calling thread's call stack and returns it.
   virtual SyncProfile* GetBacktrace() = 0;
   // Request a save from a signal handler
   virtual void RequestSave() = 0;
   // Process any outstanding request outside a signal handler.
   virtual void HandleSaveRequest() = 0;
   // Start and stop sampler.
   void Start();
   void Stop();
   // Is the sampler used for profiling?
   bool IsProfiling() const { return profiling_; }
   // Whether the sampler is running (that is, consumes resources).
   bool IsActive() const { return active_; }
   // Low overhead way to stop the sampler from ticking
   bool IsPaused() const { return paused_; }
   void SetPaused(bool value) { NoBarrier_Store(&paused_, value); }
   virtual bool ProfileThreads() const = 0;
   int EntrySize() { return entrySize_; }
   // We can't new/delete the type safely without defining it
   // (-Wdelete-incomplete). Use these Alloc/Free functions instead.
   static PlatformData* AllocPlatformData(int aThreadId);
   static void FreePlatformData(PlatformData*);
   // If we move the backtracing code into the platform files we won't
   // need to have these hacks
 #ifdef XP_WIN
   // xxxehsan sucky hack :(
   static uintptr_t GetThreadHandle(PlatformData*);
 #endif
 #ifdef XP_MACOSX
   static pthread_t GetProfiledThread(PlatformData*);
 #endif
   static std::vector<ThreadInfo*> GetRegisteredThreads() {
     return *sRegisteredThreads;
   }
   static bool RegisterCurrentThread(const char* aName,
                                     PseudoStack* aPseudoStack,
                                     bool aIsMainThread, void* stackTop);
   static void UnregisterCurrentThread();
   static void Startup();
   // Should only be called on shutdown
   static void Shutdown();
   static TableTicker* GetActiveSampler() { return sActiveSampler; }
   static void SetActiveSampler(TableTicker* sampler) { sActiveSampler = sampler; }
   static mozilla::Mutex* sRegisteredThreadsMutex;
   static bool CanNotifyObservers() {
 #if defined(SPS_OS_android) && !defined(MOZ_WIDGET_GONK)
     // Android ANR reporter uses the profiler off the main thread
     return NS_IsMainThread();
 #else
     MOZ_ASSERT(NS_IsMainThread());
     return true;
 #endif
   }
  protected:
   static std::vector<ThreadInfo*>* sRegisteredThreads;
   static TableTicker* sActiveSampler;
  private:
   void SetActive(bool value) { NoBarrier_Store(&active_, value); }
   const double interval_;
   const bool profiling_;
   Atomic32 paused_;
   Atomic32 active_;
   const int entrySize_;
   // Refactor me!
 #if defined(SPS_OS_linux) || defined(SPS_OS_android)
   bool signal_handler_installed_;
   struct sigaction old_sigprof_signal_handler_;
   struct sigaction old_sigsave_signal_handler_;
   bool signal_sender_launched_;
   pthread_t signal_sender_thread_;
 #endif
 };
 class ThreadInfo {
  public:
   ThreadInfo(const char* aName, int aThreadId, bool aIsMainThread, PseudoStack* aPseudoStack, void* aStackTop)
     : mName(strdup(aName))
     , mThreadId(aThreadId)
     , mIsMainThread(aIsMainThread)
     , mPseudoStack(aPseudoStack)
     , mPlatformData(Sampler::AllocPlatformData(aThreadId))
     , mProfile(NULL)
     , mStackTop(aStackTop) {}
   virtual ~ThreadInfo();
   const char* Name() const { return mName; }
   int ThreadId() const { return mThreadId; }
   bool IsMainThread() const { return mIsMainThread; }
   PseudoStack* Stack() const { return mPseudoStack; }
   void SetProfile(ThreadProfile* aProfile) { mProfile = aProfile; }
   ThreadProfile* Profile() const { return mProfile; }
   PlatformData* GetPlatformData() const { return mPlatformData; }
   void* StackTop() const { return mStackTop; }
  private:
   char* mName;
   int mThreadId;
   const bool mIsMainThread;
   PseudoStack* mPseudoStack;
   PlatformData* mPlatformData;
   ThreadProfile* mProfile;
   void* const mStackTop;
 };
 #endif /* ndef TOOLS_PLATFORM_H_ */

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tools/profiler/platform.h@97036ab72558 (annotated)

tools/profiler/platform.h