| // Copyright 2010 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef V8_V8_PROFILER_H_ |
| #define V8_V8_PROFILER_H_ |
| |
| #include <unordered_set> |
| #include <vector> |
| #include "v8.h" // NOLINT(build/include) |
| |
| /** |
| * Profiler support for the V8 JavaScript engine. |
| */ |
| namespace v8 { |
| |
| class HeapGraphNode; |
| struct HeapStatsUpdate; |
| |
| typedef uint32_t SnapshotObjectId; |
| |
| |
| struct CpuProfileDeoptFrame { |
| int script_id; |
| size_t position; |
| }; |
| |
| } // namespace v8 |
| |
| #ifdef V8_OS_WIN |
| template class V8_EXPORT std::vector<v8::CpuProfileDeoptFrame>; |
| #endif |
| |
| namespace v8 { |
| |
| struct V8_EXPORT CpuProfileDeoptInfo { |
| /** A pointer to a static string owned by v8. */ |
| const char* deopt_reason; |
| std::vector<CpuProfileDeoptFrame> stack; |
| }; |
| |
| } // namespace v8 |
| |
| #ifdef V8_OS_WIN |
| template class V8_EXPORT std::vector<v8::CpuProfileDeoptInfo>; |
| #endif |
| |
| namespace v8 { |
| |
| // TickSample captures the information collected for each sample. |
| struct V8_EXPORT TickSample { |
| // Internal profiling (with --prof + tools/$OS-tick-processor) wants to |
| // include the runtime function we're calling. Externally exposed tick |
| // samples don't care. |
| enum RecordCEntryFrame { kIncludeCEntryFrame, kSkipCEntryFrame }; |
| |
| TickSample() |
| : state(OTHER), |
| pc(nullptr), |
| external_callback_entry(nullptr), |
| frames_count(0), |
| has_external_callback(false), |
| update_stats(true) {} |
| |
| /** |
| * Initialize a tick sample from the isolate. |
| * \param isolate The isolate. |
| * \param state Execution state. |
| * \param record_c_entry_frame Include or skip the runtime function. |
| * \param update_stats Whether update the sample to the aggregated stats. |
| * \param use_simulator_reg_state When set to true and V8 is running under a |
| * simulator, the method will use the simulator |
| * register state rather than the one provided |
| * with |state| argument. Otherwise the method |
| * will use provided register |state| as is. |
| */ |
| void Init(Isolate* isolate, const v8::RegisterState& state, |
| RecordCEntryFrame record_c_entry_frame, bool update_stats, |
| bool use_simulator_reg_state = true); |
| /** |
| * Get a call stack sample from the isolate. |
| * \param isolate The isolate. |
| * \param state Register state. |
| * \param record_c_entry_frame Include or skip the runtime function. |
| * \param frames Caller allocated buffer to store stack frames. |
| * \param frames_limit Maximum number of frames to capture. The buffer must |
| * be large enough to hold the number of frames. |
| * \param sample_info The sample info is filled up by the function |
| * provides number of actual captured stack frames and |
| * the current VM state. |
| * \param use_simulator_reg_state When set to true and V8 is running under a |
| * simulator, the method will use the simulator |
| * register state rather than the one provided |
| * with |state| argument. Otherwise the method |
| * will use provided register |state| as is. |
| * \note GetStackSample is thread and signal safe and should only be called |
| * when the JS thread is paused or interrupted. |
| * Otherwise the behavior is undefined. |
| */ |
| static bool GetStackSample(Isolate* isolate, v8::RegisterState* state, |
| RecordCEntryFrame record_c_entry_frame, |
| void** frames, size_t frames_limit, |
| v8::SampleInfo* sample_info, |
| bool use_simulator_reg_state = true); |
| StateTag state; // The state of the VM. |
| void* pc; // Instruction pointer. |
| union { |
| void* tos; // Top stack value (*sp). |
| void* external_callback_entry; |
| }; |
| static const unsigned kMaxFramesCountLog2 = 8; |
| static const unsigned kMaxFramesCount = (1 << kMaxFramesCountLog2) - 1; |
| void* stack[kMaxFramesCount]; // Call stack. |
| unsigned frames_count : kMaxFramesCountLog2; // Number of captured frames. |
| bool has_external_callback : 1; |
| bool update_stats : 1; // Whether the sample should update aggregated stats. |
| }; |
| |
| /** |
| * CpuProfileNode represents a node in a call graph. |
| */ |
| class V8_EXPORT CpuProfileNode { |
| public: |
| struct LineTick { |
| /** The 1-based number of the source line where the function originates. */ |
| int line; |
| |
| /** The count of samples associated with the source line. */ |
| unsigned int hit_count; |
| }; |
| |
| // An annotation hinting at the source of a CpuProfileNode. |
| enum SourceType { |
| // User-supplied script with associated resource information. |
| kScript = 0, |
| // Native scripts and provided builtins. |
| kBuiltin = 1, |
| // Callbacks into native code. |
| kCallback = 2, |
| // VM-internal functions or state. |
| kInternal = 3, |
| // A node that failed to symbolize. |
| kUnresolved = 4, |
| }; |
| |
| /** Returns function name (empty string for anonymous functions.) */ |
| Local<String> GetFunctionName() const; |
| |
| /** |
| * Returns function name (empty string for anonymous functions.) |
| * The string ownership is *not* passed to the caller. It stays valid until |
| * profile is deleted. The function is thread safe. |
| */ |
| const char* GetFunctionNameStr() const; |
| |
| /** Returns id of the script where function is located. */ |
| int GetScriptId() const; |
| |
| /** Returns resource name for script from where the function originates. */ |
| Local<String> GetScriptResourceName() const; |
| |
| /** |
| * Returns resource name for script from where the function originates. |
| * The string ownership is *not* passed to the caller. It stays valid until |
| * profile is deleted. The function is thread safe. |
| */ |
| const char* GetScriptResourceNameStr() const; |
| |
| /** |
| * Return true if the script from where the function originates is flagged as |
| * being shared cross-origin. |
| */ |
| bool IsScriptSharedCrossOrigin() const; |
| |
| /** |
| * Returns the number, 1-based, of the line where the function originates. |
| * kNoLineNumberInfo if no line number information is available. |
| */ |
| int GetLineNumber() const; |
| |
| /** |
| * Returns 1-based number of the column where the function originates. |
| * kNoColumnNumberInfo if no column number information is available. |
| */ |
| int GetColumnNumber() const; |
| |
| /** |
| * Returns the number of the function's source lines that collect the samples. |
| */ |
| unsigned int GetHitLineCount() const; |
| |
| /** Returns the set of source lines that collect the samples. |
| * The caller allocates buffer and responsible for releasing it. |
| * True if all available entries are copied, otherwise false. |
| * The function copies nothing if buffer is not large enough. |
| */ |
| bool GetLineTicks(LineTick* entries, unsigned int length) const; |
| |
| /** Returns bailout reason for the function |
| * if the optimization was disabled for it. |
| */ |
| const char* GetBailoutReason() const; |
| |
| /** |
| * Returns the count of samples where the function was currently executing. |
| */ |
| unsigned GetHitCount() const; |
| |
| /** Returns function entry UID. */ |
| V8_DEPRECATE_SOON( |
| "Use GetScriptId, GetLineNumber, and GetColumnNumber instead.", |
| unsigned GetCallUid() const); |
| |
| /** Returns id of the node. The id is unique within the tree */ |
| unsigned GetNodeId() const; |
| |
| /** |
| * Gets the type of the source which the node was captured from. |
| */ |
| SourceType GetSourceType() const; |
| |
| /** Returns child nodes count of the node. */ |
| int GetChildrenCount() const; |
| |
| /** Retrieves a child node by index. */ |
| const CpuProfileNode* GetChild(int index) const; |
| |
| /** Retrieves the ancestor node, or null if the root. */ |
| const CpuProfileNode* GetParent() const; |
| |
| /** Retrieves deopt infos for the node. */ |
| const std::vector<CpuProfileDeoptInfo>& GetDeoptInfos() const; |
| |
| static const int kNoLineNumberInfo = Message::kNoLineNumberInfo; |
| static const int kNoColumnNumberInfo = Message::kNoColumnInfo; |
| }; |
| |
| |
| /** |
| * CpuProfile contains a CPU profile in a form of top-down call tree |
| * (from main() down to functions that do all the work). |
| */ |
| class V8_EXPORT CpuProfile { |
| public: |
| /** Returns CPU profile title. */ |
| Local<String> GetTitle() const; |
| |
| /** Returns the root node of the top down call tree. */ |
| const CpuProfileNode* GetTopDownRoot() const; |
| |
| /** |
| * Returns number of samples recorded. The samples are not recorded unless |
| * |record_samples| parameter of CpuProfiler::StartCpuProfiling is true. |
| */ |
| int GetSamplesCount() const; |
| |
| /** |
| * Returns profile node corresponding to the top frame the sample at |
| * the given index. |
| */ |
| const CpuProfileNode* GetSample(int index) const; |
| |
| /** |
| * Returns the timestamp of the sample. The timestamp is the number of |
| * microseconds since some unspecified starting point. |
| * The point is equal to the starting point used by GetStartTime. |
| */ |
| int64_t GetSampleTimestamp(int index) const; |
| |
| /** |
| * Returns time when the profile recording was started (in microseconds) |
| * since some unspecified starting point. |
| */ |
| int64_t GetStartTime() const; |
| |
| /** |
| * Returns time when the profile recording was stopped (in microseconds) |
| * since some unspecified starting point. |
| * The point is equal to the starting point used by GetStartTime. |
| */ |
| int64_t GetEndTime() const; |
| |
| /** |
| * Deletes the profile and removes it from CpuProfiler's list. |
| * All pointers to nodes previously returned become invalid. |
| */ |
| void Delete(); |
| }; |
| |
| enum CpuProfilingMode { |
| // In the resulting CpuProfile tree, intermediate nodes in a stack trace |
| // (from the root to a leaf) will have line numbers that point to the start |
| // line of the function, rather than the line of the callsite of the child. |
| kLeafNodeLineNumbers, |
| // In the resulting CpuProfile tree, nodes are separated based on the line |
| // number of their callsite in their parent. |
| kCallerLineNumbers, |
| }; |
| |
| /** |
| * Interface for controlling CPU profiling. Instance of the |
| * profiler can be created using v8::CpuProfiler::New method. |
| */ |
| class V8_EXPORT CpuProfiler { |
| public: |
| /** |
| * Creates a new CPU profiler for the |isolate|. The isolate must be |
| * initialized. The profiler object must be disposed after use by calling |
| * |Dispose| method. |
| */ |
| static CpuProfiler* New(Isolate* isolate); |
| |
| /** |
| * Synchronously collect current stack sample in all profilers attached to |
| * the |isolate|. The call does not affect number of ticks recorded for |
| * the current top node. |
| */ |
| static void CollectSample(Isolate* isolate); |
| |
| /** |
| * Disposes the CPU profiler object. |
| */ |
| void Dispose(); |
| |
| /** |
| * Changes default CPU profiler sampling interval to the specified number |
| * of microseconds. Default interval is 1000us. This method must be called |
| * when there are no profiles being recorded. |
| */ |
| void SetSamplingInterval(int us); |
| |
| /** |
| * Sets whether or not the profiler should prioritize consistency of sample |
| * periodicity on Windows. Disabling this can greatly reduce CPU usage, but |
| * may result in greater variance in sample timings from the platform's |
| * scheduler. Defaults to enabled. This method must be called when there are |
| * no profiles being recorded. |
| */ |
| void SetUsePreciseSampling(bool); |
| |
| /** |
| * Starts collecting CPU profile. Title may be an empty string. It |
| * is allowed to have several profiles being collected at |
| * once. Attempts to start collecting several profiles with the same |
| * title are silently ignored. While collecting a profile, functions |
| * from all security contexts are included in it. The token-based |
| * filtering is only performed when querying for a profile. |
| * |
| * |record_samples| parameter controls whether individual samples should |
| * be recorded in addition to the aggregated tree. |
| */ |
| void StartProfiling(Local<String> title, CpuProfilingMode mode, |
| bool record_samples = false); |
| /** |
| * The same as StartProfiling above, but the CpuProfilingMode defaults to |
| * kLeafNodeLineNumbers mode, which was the previous default behavior of the |
| * profiler. |
| */ |
| void StartProfiling(Local<String> title, bool record_samples = false); |
| |
| /** |
| * Stops collecting CPU profile with a given title and returns it. |
| * If the title given is empty, finishes the last profile started. |
| */ |
| CpuProfile* StopProfiling(Local<String> title); |
| |
| /** |
| * Force collection of a sample. Must be called on the VM thread. |
| * Recording the forced sample does not contribute to the aggregated |
| * profile statistics. |
| */ |
| V8_DEPRECATED("Use static CollectSample(Isolate*) instead.", |
| void CollectSample()); |
| |
| /** |
| * Tells the profiler whether the embedder is idle. |
| */ |
| V8_DEPRECATED("Use Isolate::SetIdle(bool) instead.", |
| void SetIdle(bool is_idle)); |
| |
| /** |
| * Generate more detailed source positions to code objects. This results in |
| * better results when mapping profiling samples to script source. |
| */ |
| static void UseDetailedSourcePositionsForProfiling(Isolate* isolate); |
| |
| private: |
| CpuProfiler(); |
| ~CpuProfiler(); |
| CpuProfiler(const CpuProfiler&); |
| CpuProfiler& operator=(const CpuProfiler&); |
| }; |
| |
| |
| /** |
| * HeapSnapshotEdge represents a directed connection between heap |
| * graph nodes: from retainers to retained nodes. |
| */ |
| class V8_EXPORT HeapGraphEdge { |
| public: |
| enum Type { |
| kContextVariable = 0, // A variable from a function context. |
| kElement = 1, // An element of an array. |
| kProperty = 2, // A named object property. |
| kInternal = 3, // A link that can't be accessed from JS, |
| // thus, its name isn't a real property name |
| // (e.g. parts of a ConsString). |
| kHidden = 4, // A link that is needed for proper sizes |
| // calculation, but may be hidden from user. |
| kShortcut = 5, // A link that must not be followed during |
| // sizes calculation. |
| kWeak = 6 // A weak reference (ignored by the GC). |
| }; |
| |
| /** Returns edge type (see HeapGraphEdge::Type). */ |
| Type GetType() const; |
| |
| /** |
| * Returns edge name. This can be a variable name, an element index, or |
| * a property name. |
| */ |
| Local<Value> GetName() const; |
| |
| /** Returns origin node. */ |
| const HeapGraphNode* GetFromNode() const; |
| |
| /** Returns destination node. */ |
| const HeapGraphNode* GetToNode() const; |
| }; |
| |
| |
| /** |
| * HeapGraphNode represents a node in a heap graph. |
| */ |
| class V8_EXPORT HeapGraphNode { |
| public: |
| enum Type { |
| kHidden = 0, // Hidden node, may be filtered when shown to user. |
| kArray = 1, // An array of elements. |
| kString = 2, // A string. |
| kObject = 3, // A JS object (except for arrays and strings). |
| kCode = 4, // Compiled code. |
| kClosure = 5, // Function closure. |
| kRegExp = 6, // RegExp. |
| kHeapNumber = 7, // Number stored in the heap. |
| kNative = 8, // Native object (not from V8 heap). |
| kSynthetic = 9, // Synthetic object, usually used for grouping |
| // snapshot items together. |
| kConsString = 10, // Concatenated string. A pair of pointers to strings. |
| kSlicedString = 11, // Sliced string. A fragment of another string. |
| kSymbol = 12, // A Symbol (ES6). |
| kBigInt = 13 // BigInt. |
| }; |
| |
| /** Returns node type (see HeapGraphNode::Type). */ |
| Type GetType() const; |
| |
| /** |
| * Returns node name. Depending on node's type this can be the name |
| * of the constructor (for objects), the name of the function (for |
| * closures), string value, or an empty string (for compiled code). |
| */ |
| Local<String> GetName() const; |
| |
| /** |
| * Returns node id. For the same heap object, the id remains the same |
| * across all snapshots. |
| */ |
| SnapshotObjectId GetId() const; |
| |
| /** Returns node's own size, in bytes. */ |
| size_t GetShallowSize() const; |
| |
| /** Returns child nodes count of the node. */ |
| int GetChildrenCount() const; |
| |
| /** Retrieves a child by index. */ |
| const HeapGraphEdge* GetChild(int index) const; |
| }; |
| |
| |
| /** |
| * An interface for exporting data from V8, using "push" model. |
| */ |
| class V8_EXPORT OutputStream { // NOLINT |
| public: |
| enum WriteResult { |
| kContinue = 0, |
| kAbort = 1 |
| }; |
| virtual ~OutputStream() = default; |
| /** Notify about the end of stream. */ |
| virtual void EndOfStream() = 0; |
| /** Get preferred output chunk size. Called only once. */ |
| virtual int GetChunkSize() { return 1024; } |
| /** |
| * Writes the next chunk of snapshot data into the stream. Writing |
| * can be stopped by returning kAbort as function result. EndOfStream |
| * will not be called in case writing was aborted. |
| */ |
| virtual WriteResult WriteAsciiChunk(char* data, int size) = 0; |
| /** |
| * Writes the next chunk of heap stats data into the stream. Writing |
| * can be stopped by returning kAbort as function result. EndOfStream |
| * will not be called in case writing was aborted. |
| */ |
| virtual WriteResult WriteHeapStatsChunk(HeapStatsUpdate* data, int count) { |
| return kAbort; |
| } |
| }; |
| |
| |
| /** |
| * HeapSnapshots record the state of the JS heap at some moment. |
| */ |
| class V8_EXPORT HeapSnapshot { |
| public: |
| enum SerializationFormat { |
| kJSON = 0 // See format description near 'Serialize' method. |
| }; |
| |
| /** Returns the root node of the heap graph. */ |
| const HeapGraphNode* GetRoot() const; |
| |
| /** Returns a node by its id. */ |
| const HeapGraphNode* GetNodeById(SnapshotObjectId id) const; |
| |
| /** Returns total nodes count in the snapshot. */ |
| int GetNodesCount() const; |
| |
| /** Returns a node by index. */ |
| const HeapGraphNode* GetNode(int index) const; |
| |
| /** Returns a max seen JS object Id. */ |
| SnapshotObjectId GetMaxSnapshotJSObjectId() const; |
| |
| /** |
| * Deletes the snapshot and removes it from HeapProfiler's list. |
| * All pointers to nodes, edges and paths previously returned become |
| * invalid. |
| */ |
| void Delete(); |
| |
| /** |
| * Prepare a serialized representation of the snapshot. The result |
| * is written into the stream provided in chunks of specified size. |
| * The total length of the serialized snapshot is unknown in |
| * advance, it can be roughly equal to JS heap size (that means, |
| * it can be really big - tens of megabytes). |
| * |
| * For the JSON format, heap contents are represented as an object |
| * with the following structure: |
| * |
| * { |
| * snapshot: { |
| * title: "...", |
| * uid: nnn, |
| * meta: { meta-info }, |
| * node_count: nnn, |
| * edge_count: nnn |
| * }, |
| * nodes: [nodes array], |
| * edges: [edges array], |
| * strings: [strings array] |
| * } |
| * |
| * Nodes reference strings, other nodes, and edges by their indexes |
| * in corresponding arrays. |
| */ |
| void Serialize(OutputStream* stream, |
| SerializationFormat format = kJSON) const; |
| }; |
| |
| |
| /** |
| * An interface for reporting progress and controlling long-running |
| * activities. |
| */ |
| class V8_EXPORT ActivityControl { // NOLINT |
| public: |
| enum ControlOption { |
| kContinue = 0, |
| kAbort = 1 |
| }; |
| virtual ~ActivityControl() = default; |
| /** |
| * Notify about current progress. The activity can be stopped by |
| * returning kAbort as the callback result. |
| */ |
| virtual ControlOption ReportProgressValue(int done, int total) = 0; |
| }; |
| |
| |
| /** |
| * AllocationProfile is a sampled profile of allocations done by the program. |
| * This is structured as a call-graph. |
| */ |
| class V8_EXPORT AllocationProfile { |
| public: |
| struct Allocation { |
| /** |
| * Size of the sampled allocation object. |
| */ |
| size_t size; |
| |
| /** |
| * The number of objects of such size that were sampled. |
| */ |
| unsigned int count; |
| }; |
| |
| /** |
| * Represents a node in the call-graph. |
| */ |
| struct Node { |
| /** |
| * Name of the function. May be empty for anonymous functions or if the |
| * script corresponding to this function has been unloaded. |
| */ |
| Local<String> name; |
| |
| /** |
| * Name of the script containing the function. May be empty if the script |
| * name is not available, or if the script has been unloaded. |
| */ |
| Local<String> script_name; |
| |
| /** |
| * id of the script where the function is located. May be equal to |
| * v8::UnboundScript::kNoScriptId in cases where the script doesn't exist. |
| */ |
| int script_id; |
| |
| /** |
| * Start position of the function in the script. |
| */ |
| int start_position; |
| |
| /** |
| * 1-indexed line number where the function starts. May be |
| * kNoLineNumberInfo if no line number information is available. |
| */ |
| int line_number; |
| |
| /** |
| * 1-indexed column number where the function starts. May be |
| * kNoColumnNumberInfo if no line number information is available. |
| */ |
| int column_number; |
| |
| /** |
| * Unique id of the node. |
| */ |
| uint32_t node_id; |
| |
| /** |
| * List of callees called from this node for which we have sampled |
| * allocations. The lifetime of the children is scoped to the containing |
| * AllocationProfile. |
| */ |
| std::vector<Node*> children; |
| |
| /** |
| * List of self allocations done by this node in the call-graph. |
| */ |
| std::vector<Allocation> allocations; |
| }; |
| |
| /** |
| * Represent a single sample recorded for an allocation. |
| */ |
| struct Sample { |
| /** |
| * id of the node in the profile tree. |
| */ |
| uint32_t node_id; |
| |
| /** |
| * Size of the sampled allocation object. |
| */ |
| size_t size; |
| |
| /** |
| * The number of objects of such size that were sampled. |
| */ |
| unsigned int count; |
| |
| /** |
| * Unique time-ordered id of the allocation sample. Can be used to track |
| * what samples were added or removed between two snapshots. |
| */ |
| uint64_t sample_id; |
| }; |
| |
| /** |
| * Returns the root node of the call-graph. The root node corresponds to an |
| * empty JS call-stack. The lifetime of the returned Node* is scoped to the |
| * containing AllocationProfile. |
| */ |
| virtual Node* GetRootNode() = 0; |
| virtual const std::vector<Sample>& GetSamples() = 0; |
| |
| virtual ~AllocationProfile() = default; |
| |
| static const int kNoLineNumberInfo = Message::kNoLineNumberInfo; |
| static const int kNoColumnNumberInfo = Message::kNoColumnInfo; |
| }; |
| |
| /** |
| * An object graph consisting of embedder objects and V8 objects. |
| * Edges of the graph are strong references between the objects. |
| * The embedder can build this graph during heap snapshot generation |
| * to include the embedder objects in the heap snapshot. |
| * Usage: |
| * 1) Define derived class of EmbedderGraph::Node for embedder objects. |
| * 2) Set the build embedder graph callback on the heap profiler using |
| * HeapProfiler::AddBuildEmbedderGraphCallback. |
| * 3) In the callback use graph->AddEdge(node1, node2) to add an edge from |
| * node1 to node2. |
| * 4) To represent references from/to V8 object, construct V8 nodes using |
| * graph->V8Node(value). |
| */ |
| class V8_EXPORT EmbedderGraph { |
| public: |
| class Node { |
| public: |
| Node() = default; |
| virtual ~Node() = default; |
| virtual const char* Name() = 0; |
| virtual size_t SizeInBytes() = 0; |
| /** |
| * The corresponding V8 wrapper node if not null. |
| * During heap snapshot generation the embedder node and the V8 wrapper |
| * node will be merged into one node to simplify retaining paths. |
| */ |
| virtual Node* WrapperNode() { return nullptr; } |
| virtual bool IsRootNode() { return false; } |
| /** Must return true for non-V8 nodes. */ |
| virtual bool IsEmbedderNode() { return true; } |
| /** |
| * Optional name prefix. It is used in Chrome for tagging detached nodes. |
| */ |
| virtual const char* NamePrefix() { return nullptr; } |
| |
| private: |
| Node(const Node&) = delete; |
| Node& operator=(const Node&) = delete; |
| }; |
| |
| /** |
| * Returns a node corresponding to the given V8 value. Ownership is not |
| * transferred. The result pointer is valid while the graph is alive. |
| */ |
| virtual Node* V8Node(const v8::Local<v8::Value>& value) = 0; |
| |
| /** |
| * Adds the given node to the graph and takes ownership of the node. |
| * Returns a raw pointer to the node that is valid while the graph is alive. |
| */ |
| virtual Node* AddNode(std::unique_ptr<Node> node) = 0; |
| |
| /** |
| * Adds an edge that represents a strong reference from the given |
| * node |from| to the given node |to|. The nodes must be added to the graph |
| * before calling this function. |
| * |
| * If name is nullptr, the edge will have auto-increment indexes, otherwise |
| * it will be named accordingly. |
| */ |
| virtual void AddEdge(Node* from, Node* to, const char* name = nullptr) = 0; |
| |
| virtual ~EmbedderGraph() = default; |
| }; |
| |
| /** |
| * Interface for controlling heap profiling. Instance of the |
| * profiler can be retrieved using v8::Isolate::GetHeapProfiler. |
| */ |
| class V8_EXPORT HeapProfiler { |
| public: |
| enum SamplingFlags { |
| kSamplingNoFlags = 0, |
| kSamplingForceGC = 1 << 0, |
| }; |
| |
| /** |
| * Callback function invoked during heap snapshot generation to retrieve |
| * the embedder object graph. The callback should use graph->AddEdge(..) to |
| * add references between the objects. |
| * The callback must not trigger garbage collection in V8. |
| */ |
| typedef void (*BuildEmbedderGraphCallback)(v8::Isolate* isolate, |
| v8::EmbedderGraph* graph, |
| void* data); |
| |
| /** Returns the number of snapshots taken. */ |
| int GetSnapshotCount(); |
| |
| /** Returns a snapshot by index. */ |
| const HeapSnapshot* GetHeapSnapshot(int index); |
| |
| /** |
| * Returns SnapshotObjectId for a heap object referenced by |value| if |
| * it has been seen by the heap profiler, kUnknownObjectId otherwise. |
| */ |
| SnapshotObjectId GetObjectId(Local<Value> value); |
| |
| /** |
| * Returns heap object with given SnapshotObjectId if the object is alive, |
| * otherwise empty handle is returned. |
| */ |
| Local<Value> FindObjectById(SnapshotObjectId id); |
| |
| /** |
| * Clears internal map from SnapshotObjectId to heap object. The new objects |
| * will not be added into it unless a heap snapshot is taken or heap object |
| * tracking is kicked off. |
| */ |
| void ClearObjectIds(); |
| |
| /** |
| * A constant for invalid SnapshotObjectId. GetSnapshotObjectId will return |
| * it in case heap profiler cannot find id for the object passed as |
| * parameter. HeapSnapshot::GetNodeById will always return NULL for such id. |
| */ |
| static const SnapshotObjectId kUnknownObjectId = 0; |
| |
| /** |
| * Callback interface for retrieving user friendly names of global objects. |
| */ |
| class ObjectNameResolver { |
| public: |
| /** |
| * Returns name to be used in the heap snapshot for given node. Returned |
| * string must stay alive until snapshot collection is completed. |
| */ |
| virtual const char* GetName(Local<Object> object) = 0; |
| |
| protected: |
| virtual ~ObjectNameResolver() = default; |
| }; |
| |
| /** |
| * Takes a heap snapshot and returns it. |
| */ |
| const HeapSnapshot* TakeHeapSnapshot( |
| ActivityControl* control = nullptr, |
| ObjectNameResolver* global_object_name_resolver = nullptr); |
| |
| /** |
| * Starts tracking of heap objects population statistics. After calling |
| * this method, all heap objects relocations done by the garbage collector |
| * are being registered. |
| * |
| * |track_allocations| parameter controls whether stack trace of each |
| * allocation in the heap will be recorded and reported as part of |
| * HeapSnapshot. |
| */ |
| void StartTrackingHeapObjects(bool track_allocations = false); |
| |
| /** |
| * Adds a new time interval entry to the aggregated statistics array. The |
| * time interval entry contains information on the current heap objects |
| * population size. The method also updates aggregated statistics and |
| * reports updates for all previous time intervals via the OutputStream |
| * object. Updates on each time interval are provided as a stream of the |
| * HeapStatsUpdate structure instances. |
| * If |timestamp_us| is supplied, timestamp of the new entry will be written |
| * into it. The return value of the function is the last seen heap object Id. |
| * |
| * StartTrackingHeapObjects must be called before the first call to this |
| * method. |
| */ |
| SnapshotObjectId GetHeapStats(OutputStream* stream, |
| int64_t* timestamp_us = nullptr); |
| |
| /** |
| * Stops tracking of heap objects population statistics, cleans up all |
| * collected data. StartHeapObjectsTracking must be called again prior to |
| * calling GetHeapStats next time. |
| */ |
| void StopTrackingHeapObjects(); |
| |
| /** |
| * Starts gathering a sampling heap profile. A sampling heap profile is |
| * similar to tcmalloc's heap profiler and Go's mprof. It samples object |
| * allocations and builds an online 'sampling' heap profile. At any point in |
| * time, this profile is expected to be a representative sample of objects |
| * currently live in the system. Each sampled allocation includes the stack |
| * trace at the time of allocation, which makes this really useful for memory |
| * leak detection. |
| * |
| * This mechanism is intended to be cheap enough that it can be used in |
| * production with minimal performance overhead. |
| * |
| * Allocations are sampled using a randomized Poisson process. On average, one |
| * allocation will be sampled every |sample_interval| bytes allocated. The |
| * |stack_depth| parameter controls the maximum number of stack frames to be |
| * captured on each allocation. |
| * |
| * NOTE: This is a proof-of-concept at this point. Right now we only sample |
| * newspace allocations. Support for paged space allocation (e.g. pre-tenured |
| * objects, large objects, code objects, etc.) and native allocations |
| * doesn't exist yet, but is anticipated in the future. |
| * |
| * Objects allocated before the sampling is started will not be included in |
| * the profile. |
| * |
| * Returns false if a sampling heap profiler is already running. |
| */ |
| bool StartSamplingHeapProfiler(uint64_t sample_interval = 512 * 1024, |
| int stack_depth = 16, |
| SamplingFlags flags = kSamplingNoFlags); |
| |
| /** |
| * Stops the sampling heap profile and discards the current profile. |
| */ |
| void StopSamplingHeapProfiler(); |
| |
| /** |
| * Returns the sampled profile of allocations allocated (and still live) since |
| * StartSamplingHeapProfiler was called. The ownership of the pointer is |
| * transferred to the caller. Returns nullptr if sampling heap profiler is not |
| * active. |
| */ |
| AllocationProfile* GetAllocationProfile(); |
| |
| /** |
| * Deletes all snapshots taken. All previously returned pointers to |
| * snapshots and their contents become invalid after this call. |
| */ |
| void DeleteAllHeapSnapshots(); |
| |
| void AddBuildEmbedderGraphCallback(BuildEmbedderGraphCallback callback, |
| void* data); |
| void RemoveBuildEmbedderGraphCallback(BuildEmbedderGraphCallback callback, |
| void* data); |
| |
| /** |
| * Default value of persistent handle class ID. Must not be used to |
| * define a class. Can be used to reset a class of a persistent |
| * handle. |
| */ |
| static const uint16_t kPersistentHandleNoClassId = 0; |
| |
| private: |
| HeapProfiler(); |
| ~HeapProfiler(); |
| HeapProfiler(const HeapProfiler&); |
| HeapProfiler& operator=(const HeapProfiler&); |
| }; |
| |
| /** |
| * A struct for exporting HeapStats data from V8, using "push" model. |
| * See HeapProfiler::GetHeapStats. |
| */ |
| struct HeapStatsUpdate { |
| HeapStatsUpdate(uint32_t index, uint32_t count, uint32_t size) |
| : index(index), count(count), size(size) { } |
| uint32_t index; // Index of the time interval that was changed. |
| uint32_t count; // New value of count field for the interval with this index. |
| uint32_t size; // New value of size field for the interval with this index. |
| }; |
| |
| #define CODE_EVENTS_LIST(V) \ |
| V(Builtin) \ |
| V(Callback) \ |
| V(Eval) \ |
| V(Function) \ |
| V(InterpretedFunction) \ |
| V(Handler) \ |
| V(BytecodeHandler) \ |
| V(LazyCompile) \ |
| V(RegExp) \ |
| V(Script) \ |
| V(Stub) |
| |
| /** |
| * Note that this enum may be extended in the future. Please include a default |
| * case if this enum is used in a switch statement. |
| */ |
| enum CodeEventType { |
| kUnknownType = 0 |
| #define V(Name) , k##Name##Type |
| CODE_EVENTS_LIST(V) |
| #undef V |
| }; |
| |
| /** |
| * Representation of a code creation event |
| */ |
| class V8_EXPORT CodeEvent { |
| public: |
| uintptr_t GetCodeStartAddress(); |
| size_t GetCodeSize(); |
| Local<String> GetFunctionName(); |
| Local<String> GetScriptName(); |
| int GetScriptLine(); |
| int GetScriptColumn(); |
| /** |
| * NOTE (mmarchini): We can't allocate objects in the heap when we collect |
| * existing code, and both the code type and the comment are not stored in the |
| * heap, so we return those as const char*. |
| */ |
| CodeEventType GetCodeType(); |
| const char* GetComment(); |
| |
| static const char* GetCodeEventTypeName(CodeEventType code_event_type); |
| }; |
| |
| /** |
| * Interface to listen to code creation events. |
| */ |
| class V8_EXPORT CodeEventHandler { |
| public: |
| /** |
| * Creates a new listener for the |isolate|. The isolate must be initialized. |
| * The listener object must be disposed after use by calling |Dispose| method. |
| * Multiple listeners can be created for the same isolate. |
| */ |
| explicit CodeEventHandler(Isolate* isolate); |
| virtual ~CodeEventHandler(); |
| |
| virtual void Handle(CodeEvent* code_event) = 0; |
| |
| void Enable(); |
| void Disable(); |
| |
| private: |
| CodeEventHandler(); |
| CodeEventHandler(const CodeEventHandler&); |
| CodeEventHandler& operator=(const CodeEventHandler&); |
| void* internal_listener_; |
| }; |
| |
| } // namespace v8 |
| |
| |
| #endif // V8_V8_PROFILER_H_ |