gecko/xpcom/threads/ThreadStackHelper.h
Jim Chen 0fb099680a Bug 1196381 - Eliminate breakpad dependency in ThreadStackHelper; r=nfroyd r=snorp
The breakpad dependency in ThreadStackHelper is preventing us from
upgrading our in-tree copy to a newer version (bug 1069556). This patch
gets rid of that dependency. This makes native stack frames not work
for BHR, but because of the ftp.m.o decommissioning, native
symbolication was already broken and naive stack frames already don't
work, so we don't really lose anything from this patch.

Eventually we want to make ThreadStackHelper use other means of
unwinding, such as LUL for Linux

I added | #if 0 | around the code to fill the thread context, but left
the code in because I think we'll evenually want to reuse some of that
code.
2015-09-18 09:17:10 -04:00

148 lines
3.7 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_ThreadStackHelper_h
#define mozilla_ThreadStackHelper_h
#include "mozilla/ThreadHangStats.h"
#include "GeckoProfiler.h"
#include <stddef.h>
#if defined(XP_LINUX)
#include <signal.h>
#include <semaphore.h>
#include <sys/types.h>
#elif defined(XP_WIN)
#include <windows.h>
#elif defined(XP_MACOSX)
#include <mach/mach.h>
#endif
// Support pseudostack on these platforms.
#if defined(XP_LINUX) || defined(XP_WIN) || defined(XP_MACOSX)
# ifdef MOZ_ENABLE_PROFILER_SPS
# define MOZ_THREADSTACKHELPER_PSEUDO
# endif
#endif
#ifdef MOZ_THREADSTACKHELPER_PSEUDO
# define MOZ_THREADSTACKHELPER_NATIVE
# if defined(__i386__) || defined(_M_IX86)
# define MOZ_THREADSTACKHELPER_X86
# elif defined(__x86_64__) || defined(_M_X64)
# define MOZ_THREADSTACKHELPER_X64
# elif defined(__arm__) || defined(_M_ARM)
# define MOZ_THREADSTACKHELPER_ARM
# else
// Unsupported architecture
# undef MOZ_THREADSTACKHELPER_NATIVE
# endif
#endif
namespace mozilla {
/**
* ThreadStackHelper is used to retrieve the profiler pseudo-stack of a
* thread, as an alternative of using the profiler to take a profile.
* The target thread first declares an ThreadStackHelper instance;
* then another thread can call ThreadStackHelper::GetStack to retrieve
* the pseudo-stack of the target thread at that instant.
*
* Only non-copying labels are included in the stack, which means labels
* with custom text and markers are not included.
*/
class ThreadStackHelper
{
public:
typedef Telemetry::HangStack Stack;
private:
Stack* mStackToFill;
#ifdef MOZ_THREADSTACKHELPER_PSEUDO
const PseudoStack* const mPseudoStack;
#ifdef MOZ_THREADSTACKHELPER_NATIVE
class ThreadContext;
// Set to non-null if GetStack should get the thread context.
ThreadContext* mContextToFill;
intptr_t mThreadStackBase;
#endif
size_t mMaxStackSize;
size_t mMaxBufferSize;
#endif
bool PrepareStackBuffer(Stack& aStack);
void FillStackBuffer();
void FillThreadContext(void* aContext = nullptr);
#ifdef MOZ_THREADSTACKHELPER_PSEUDO
const char* AppendJSEntry(const volatile StackEntry* aEntry,
intptr_t& aAvailableBufferSize,
const char* aPrevLabel);
#endif
#ifdef MOZ_THREADSTACKHELPER_NATIVE
void GetThreadStackBase();
#endif
public:
/**
* Initialize ThreadStackHelper. Must be called from main thread.
*/
static void Startup();
/**
* Uninitialize ThreadStackHelper. Must be called from main thread.
*/
static void Shutdown();
/**
* Create a ThreadStackHelper instance targeting the current thread.
*/
ThreadStackHelper();
~ThreadStackHelper();
/**
* Retrieve the current pseudostack of the thread associated
* with this ThreadStackHelper.
*
* @param aStack Stack instance to be filled.
*/
void GetStack(Stack& aStack);
/**
* Retrieve the current native stack of the thread associated
* with this ThreadStackHelper.
*
* @param aNativeStack Stack instance to be filled.
*/
void GetNativeStack(Stack& aStack);
#if defined(XP_LINUX)
private:
static int sInitialized;
static int sFillStackSignum;
static void FillStackHandler(int aSignal, siginfo_t* aInfo, void* aContext);
sem_t mSem;
pid_t mThreadID;
#elif defined(XP_WIN)
private:
bool mInitialized;
HANDLE mThreadID;
#elif defined(XP_MACOSX)
private:
thread_act_t mThreadID;
#endif
};
} // namespace mozilla
#endif // mozilla_ThreadStackHelper_h