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authorwolfbeast <mcwerewolf@gmail.com>2018-05-24 14:06:04 +0200
committerwolfbeast <mcwerewolf@gmail.com>2018-05-24 14:06:04 +0200
commitac25827a87d86f1cf9e48aab6605f77a2c89041a (patch)
treec3533a008e606f4f6393e838b4305cf6d07f47d2 /tools/profiler/public/PseudoStack.h
parentc8b38a18031f6ae0fca8b2bef73daa86f6f96ae8 (diff)
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Remove SPS profiler.
- Conditionals and code blocks. (MOZ_ENABLE_PROFILER_SPS) - Stub out several profiler-only functions.
Diffstat (limited to 'tools/profiler/public/PseudoStack.h')
-rw-r--r--tools/profiler/public/PseudoStack.h469
1 files changed, 0 insertions, 469 deletions
diff --git a/tools/profiler/public/PseudoStack.h b/tools/profiler/public/PseudoStack.h
deleted file mode 100644
index f9e3836ea..000000000
--- a/tools/profiler/public/PseudoStack.h
+++ /dev/null
@@ -1,469 +0,0 @@
-/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* 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 PROFILER_PSEUDO_STACK_H_
-#define PROFILER_PSEUDO_STACK_H_
-
-#include "mozilla/ArrayUtils.h"
-#include <stdint.h>
-#include "js/ProfilingStack.h"
-#include <stdlib.h>
-#include "mozilla/Atomics.h"
-#ifndef SPS_STANDALONE
-#include "nsISupportsImpl.h"
-#endif
-
-/* we duplicate this code here to avoid header dependencies
- * which make it more difficult to include in other places */
-#if defined(_M_X64) || defined(__x86_64__)
-#define V8_HOST_ARCH_X64 1
-#elif defined(_M_IX86) || defined(__i386__) || defined(__i386)
-#define V8_HOST_ARCH_IA32 1
-#elif defined(__ARMEL__)
-#define V8_HOST_ARCH_ARM 1
-#else
-#warning Please add support for your architecture in chromium_types.h
-#endif
-
-// STORE_SEQUENCER: Because signals can interrupt our profile modification
-// we need to make stores are not re-ordered by the compiler
-// or hardware to make sure the profile is consistent at
-// every point the signal can fire.
-#ifdef V8_HOST_ARCH_ARM
-// TODO Is there something cheaper that will prevent
-// memory stores from being reordered
-
-typedef void (*LinuxKernelMemoryBarrierFunc)(void);
-LinuxKernelMemoryBarrierFunc pLinuxKernelMemoryBarrier __attribute__((weak)) =
- (LinuxKernelMemoryBarrierFunc) 0xffff0fa0;
-
-# define STORE_SEQUENCER() pLinuxKernelMemoryBarrier()
-#elif defined(V8_HOST_ARCH_IA32) || defined(V8_HOST_ARCH_X64)
-# if defined(_MSC_VER)
-# include <intrin.h>
-# define STORE_SEQUENCER() _ReadWriteBarrier();
-# elif defined(__INTEL_COMPILER)
-# define STORE_SEQUENCER() __memory_barrier();
-# elif __GNUC__
-# define STORE_SEQUENCER() asm volatile("" ::: "memory");
-# else
-# error "Memory clobber not supported for your compiler."
-# endif
-#else
-# error "Memory clobber not supported for your platform."
-#endif
-
-// We can't include <algorithm> because it causes issues on OS X, so we use
-// our own min function.
-static inline uint32_t sMin(uint32_t l, uint32_t r) {
- return l < r ? l : r;
-}
-
-// A stack entry exists to allow the JS engine to inform SPS of the current
-// backtrace, but also to instrument particular points in C++ in case stack
-// walking is not available on the platform we are running on.
-//
-// Each entry has a descriptive string, a relevant stack address, and some extra
-// information the JS engine might want to inform SPS of. This class inherits
-// from the JS engine's version of the entry to ensure that the size and layout
-// of the two representations are consistent.
-class StackEntry : public js::ProfileEntry
-{
-};
-
-class ProfilerMarkerPayload;
-template<typename T>
-class ProfilerLinkedList;
-class SpliceableJSONWriter;
-class UniqueStacks;
-
-class ProfilerMarker {
- friend class ProfilerLinkedList<ProfilerMarker>;
-public:
- explicit ProfilerMarker(const char* aMarkerName,
- ProfilerMarkerPayload* aPayload = nullptr,
- double aTime = 0);
-
- ~ProfilerMarker();
-
- const char* GetMarkerName() const {
- return mMarkerName;
- }
-
- void StreamJSON(SpliceableJSONWriter& aWriter, UniqueStacks& aUniqueStacks) const;
-
- void SetGeneration(uint32_t aGenID);
-
- bool HasExpired(uint32_t aGenID) const {
- return mGenID + 2 <= aGenID;
- }
-
- double GetTime() const;
-
-private:
- char* mMarkerName;
- ProfilerMarkerPayload* mPayload;
- ProfilerMarker* mNext;
- double mTime;
- uint32_t mGenID;
-};
-
-template<typename T>
-class ProfilerLinkedList {
-public:
- ProfilerLinkedList()
- : mHead(nullptr)
- , mTail(nullptr)
- {}
-
- void insert(T* elem)
- {
- if (!mTail) {
- mHead = elem;
- mTail = elem;
- } else {
- mTail->mNext = elem;
- mTail = elem;
- }
- elem->mNext = nullptr;
- }
-
- T* popHead()
- {
- if (!mHead) {
- MOZ_ASSERT(false);
- return nullptr;
- }
-
- T* head = mHead;
-
- mHead = head->mNext;
- if (!mHead) {
- mTail = nullptr;
- }
-
- return head;
- }
-
- const T* peek() {
- return mHead;
- }
-
-private:
- T* mHead;
- T* mTail;
-};
-
-typedef ProfilerLinkedList<ProfilerMarker> ProfilerMarkerLinkedList;
-
-template<typename T>
-class ProfilerSignalSafeLinkedList {
-public:
- ProfilerSignalSafeLinkedList()
- : mSignalLock(false)
- {}
-
- ~ProfilerSignalSafeLinkedList()
- {
- if (mSignalLock) {
- // Some thread is modifying the list. We should only be released on that
- // thread.
- abort();
- }
-
- while (mList.peek()) {
- delete mList.popHead();
- }
- }
-
- // Insert an item into the list.
- // Must only be called from the owning thread.
- // Must not be called while the list from accessList() is being accessed.
- // In the profiler, we ensure that by interrupting the profiled thread
- // (which is the one that owns this list and calls insert() on it) until
- // we're done reading the list from the signal handler.
- void insert(T* aElement) {
- MOZ_ASSERT(aElement);
-
- mSignalLock = true;
- STORE_SEQUENCER();
-
- mList.insert(aElement);
-
- STORE_SEQUENCER();
- mSignalLock = false;
- }
-
- // Called within signal, from any thread, possibly while insert() is in the
- // middle of modifying the list (on the owning thread). Will return null if
- // that is the case.
- // Function must be reentrant.
- ProfilerLinkedList<T>* accessList()
- {
- if (mSignalLock) {
- return nullptr;
- }
- return &mList;
- }
-
-private:
- ProfilerLinkedList<T> mList;
-
- // If this is set, then it's not safe to read the list because its contents
- // are being changed.
- volatile bool mSignalLock;
-};
-
-// Stub eventMarker function for js-engine event generation.
-void ProfilerJSEventMarker(const char *event);
-
-// the PseudoStack members are read by signal
-// handlers, so the mutation of them needs to be signal-safe.
-struct PseudoStack
-{
-public:
- // Create a new PseudoStack and acquire a reference to it.
- static PseudoStack *create()
- {
- return new PseudoStack();
- }
-
- // This is called on every profiler restart. Put things that should happen at that time here.
- void reinitializeOnResume() {
- // This is needed to cause an initial sample to be taken from sleeping threads. Otherwise sleeping
- // threads would not have any samples to copy forward while sleeping.
- mSleepId++;
- }
-
- void addMarker(const char* aMarkerStr, ProfilerMarkerPayload* aPayload, double aTime)
- {
- ProfilerMarker* marker = new ProfilerMarker(aMarkerStr, aPayload, aTime);
- mPendingMarkers.insert(marker);
- }
-
- // called within signal. Function must be reentrant
- ProfilerMarkerLinkedList* getPendingMarkers()
- {
- // The profiled thread is interrupted, so we can access the list safely.
- // Unless the profiled thread was in the middle of changing the list when
- // we interrupted it - in that case, accessList() will return null.
- return mPendingMarkers.accessList();
- }
-
- void push(const char *aName, js::ProfileEntry::Category aCategory, uint32_t line)
- {
- push(aName, aCategory, nullptr, false, line);
- }
-
- void push(const char *aName, js::ProfileEntry::Category aCategory,
- void *aStackAddress, bool aCopy, uint32_t line)
- {
- if (size_t(mStackPointer) >= mozilla::ArrayLength(mStack)) {
- mStackPointer++;
- return;
- }
-
- // In order to ensure this object is kept alive while it is
- // active, we acquire a reference at the outermost push. This is
- // released by the corresponding pop.
- if (mStackPointer == 0) {
- ref();
- }
-
- volatile StackEntry &entry = mStack[mStackPointer];
-
- // Make sure we increment the pointer after the name has
- // been written such that mStack is always consistent.
- entry.initCppFrame(aStackAddress, line);
- entry.setLabel(aName);
- MOZ_ASSERT(entry.flags() == js::ProfileEntry::IS_CPP_ENTRY);
- entry.setCategory(aCategory);
-
- // Track if mLabel needs a copy.
- if (aCopy)
- entry.setFlag(js::ProfileEntry::FRAME_LABEL_COPY);
- else
- entry.unsetFlag(js::ProfileEntry::FRAME_LABEL_COPY);
-
- // Prevent the optimizer from re-ordering these instructions
- STORE_SEQUENCER();
- mStackPointer++;
- }
-
- // Pop the stack. If the stack is empty and all other references to
- // this PseudoStack have been dropped, then the PseudoStack is
- // deleted and "false" is returned. Otherwise "true" is returned.
- bool popAndMaybeDelete()
- {
- mStackPointer--;
- if (mStackPointer == 0) {
- // Release our self-owned reference count. See 'push'.
- deref();
- return false;
- } else {
- return true;
- }
- }
- bool isEmpty()
- {
- return mStackPointer == 0;
- }
- uint32_t stackSize() const
- {
- return sMin(mStackPointer, mozilla::sig_safe_t(mozilla::ArrayLength(mStack)));
- }
-
- void sampleContext(JSContext* context) {
-#ifndef SPS_STANDALONE
- if (mContext && !context) {
- // On JS shut down, flush the current buffer as stringifying JIT samples
- // requires a live JSContext.
- flushSamplerOnJSShutdown();
- }
-
- mContext = context;
-
- if (!context) {
- return;
- }
-
- static_assert(sizeof(mStack[0]) == sizeof(js::ProfileEntry),
- "mStack must be binary compatible with js::ProfileEntry.");
- js::SetContextProfilingStack(context,
- (js::ProfileEntry*) mStack,
- (uint32_t*) &mStackPointer,
- (uint32_t) mozilla::ArrayLength(mStack));
- if (mStartJSSampling)
- enableJSSampling();
-#endif
- }
-#ifndef SPS_STANDALONE
- void enableJSSampling() {
- if (mContext) {
- js::EnableContextProfilingStack(mContext, true);
- js::RegisterContextProfilingEventMarker(mContext, &ProfilerJSEventMarker);
- mStartJSSampling = false;
- } else {
- mStartJSSampling = true;
- }
- }
- void jsOperationCallback() {
- if (mStartJSSampling)
- enableJSSampling();
- }
- void disableJSSampling() {
- mStartJSSampling = false;
- if (mContext)
- js::EnableContextProfilingStack(mContext, false);
- }
-#endif
-
- // Keep a list of active checkpoints
- StackEntry volatile mStack[1024];
- private:
-
- // A PseudoStack can only be created via the "create" method.
- PseudoStack()
- : mStackPointer(0)
- , mSleepId(0)
- , mSleepIdObserved(0)
- , mSleeping(false)
- , mRefCnt(1)
-#ifndef SPS_STANDALONE
- , mContext(nullptr)
-#endif
- , mStartJSSampling(false)
- , mPrivacyMode(false)
- {
- MOZ_COUNT_CTOR(PseudoStack);
- }
-
- // A PseudoStack can only be deleted via deref.
- ~PseudoStack() {
- MOZ_COUNT_DTOR(PseudoStack);
- if (mStackPointer != 0) {
- // We're releasing the pseudostack while it's still in use.
- // The label macros keep a non ref counted reference to the
- // stack to avoid a TLS. If these are not all cleared we will
- // get a use-after-free so better to crash now.
- abort();
- }
- }
-
- // No copying.
- PseudoStack(const PseudoStack&) = delete;
- void operator=(const PseudoStack&) = delete;
-
- void flushSamplerOnJSShutdown();
-
- // Keep a list of pending markers that must be moved
- // to the circular buffer
- ProfilerSignalSafeLinkedList<ProfilerMarker> mPendingMarkers;
- // This may exceed the length of mStack, so instead use the stackSize() method
- // to determine the number of valid samples in mStack
- mozilla::sig_safe_t mStackPointer;
- // Incremented at every sleep/wake up of the thread
- int mSleepId;
- // Previous id observed. If this is not the same as mSleepId, this thread is not sleeping in the same place any more
- mozilla::Atomic<int> mSleepIdObserved;
- // Keeps tack of whether the thread is sleeping or not (1 when sleeping 0 when awake)
- mozilla::Atomic<int> mSleeping;
- // This class is reference counted because it must be kept alive by
- // the ThreadInfo, by the reference from tlsPseudoStack, and by the
- // current thread when callbacks are in progress.
- mozilla::Atomic<int> mRefCnt;
-
- public:
-#ifndef SPS_STANDALONE
- // The context which is being sampled
- JSContext *mContext;
-#endif
- // Start JS Profiling when possible
- bool mStartJSSampling;
- bool mPrivacyMode;
-
- enum SleepState {NOT_SLEEPING, SLEEPING_FIRST, SLEEPING_AGAIN};
-
- // The first time this is called per sleep cycle we return SLEEPING_FIRST
- // and any other subsequent call within the same sleep cycle we return SLEEPING_AGAIN
- SleepState observeSleeping() {
- if (mSleeping != 0) {
- if (mSleepIdObserved == mSleepId) {
- return SLEEPING_AGAIN;
- } else {
- mSleepIdObserved = mSleepId;
- return SLEEPING_FIRST;
- }
- } else {
- return NOT_SLEEPING;
- }
- }
-
-
- // Call this whenever the current thread sleeps or wakes up
- // Calling setSleeping with the same value twice in a row is an error
- void setSleeping(int sleeping) {
- MOZ_ASSERT(mSleeping != sleeping);
- mSleepId++;
- mSleeping = sleeping;
- }
-
- bool isSleeping() {
- return !!mSleeping;
- }
-
- void ref() {
- ++mRefCnt;
- }
-
- void deref() {
- int newValue = --mRefCnt;
- if (newValue == 0) {
- delete this;
- }
- }
-};
-
-#endif