Class holding the instructions and function call hierarchy obtained from decoding a trace, as well as a position cursor used when reverse debugging the trace. More...

#include <DecodedThread.h>

Inheritance diagram for lldb_private::trace_intel_pt::DecodedThread:

[legend]

Classes
struct	ErrorStats

struct	EventsStats

struct	NanosecondsRange
	A structure that represents a maximal range of trace items associated to the same non-interpolated timestamps in nanoseconds. More...

union	TraceItemStorage
	We use a union to optimize the memory usage for the different kinds of trace items. More...

struct	TSCRange
	A structure that represents a maximal range of trace items associated to the same TSC value. More...

Public Types
using	TSC = uint64_t

Public Member Functions
	DecodedThread (lldb::ThreadSP thread_sp, const std::optional< LinuxPerfZeroTscConversion > &tsc_conversion)

uint64_t	GetItemsCount () const
	Get the total number of instruction, errors and events from the decoded trace.

const char *	GetErrorByIndex (uint64_t item_index) const

lldb::TraceItemKind	GetItemKindByIndex (uint64_t item_index) const

lldb::TraceEvent	GetEventByIndex (int item_index) const

lldb::cpu_id_t	GetCPUByIndex (uint64_t item_index) const
	Get the most recent CPU id before or at the given trace item index.

lldb::addr_t	GetSyncPointOffsetByIndex (uint64_t item_index) const

std::optional< DecodedThread::TSCRange >	GetTSCRangeByIndex (uint64_t item_index) const
	Get a maximal range of trace items that include the given `item_index` that have the same TSC value.

std::optional< DecodedThread::NanosecondsRange >	GetNanosecondsRangeByIndex (uint64_t item_index)
	Get a maximal range of trace items that include the given `item_index` that have the same nanoseconds timestamp without interpolation.

lldb::addr_t	GetInstructionLoadAddress (uint64_t item_index) const

uint64_t	GetTotalInstructionCount () const

const EventsStats &	GetEventsStats () const
	Return an object with statistics of the trace events that happened.

const ErrorStats &	GetErrorStats () const
	Return an object with statistics of the trace errors that happened.

size_t	CalculateApproximateMemoryUsage () const
	The approximate size in bytes used by this instance, including all the already decoded instructions.

lldb::ThreadSP	GetThread ()

void	NotifyTsc (TSC tsc)
	Notify this object that a new tsc has been seen.

void	NotifyCPU (lldb::cpu_id_t cpu_id)
	Notify this object that a CPU has been seen.

void	NotifySyncPoint (lldb::addr_t psb_offset)
	Notify this object that a new PSB has been seen.

void	AppendError (const IntelPTError &error)
	Append a decoding error.

void	AppendCustomError (llvm::StringRef error, bool fatal=false)
	Append a custom decoding.

void	AppendEvent (lldb::TraceEvent)
	Append an event.

void	AppendInstruction (const pt_insn &insn)
	Append an instruction.

Private Member Functions
DecodedThread::TraceItemStorage &	CreateNewTraceItem (lldb::TraceItemKind kind)
	Create a new trace item.

Private Attributes
lldb::ThreadSP	m_thread_sp
	When adding new members to this class, make sure to update CalculateApproximateMemoryUsage() accordingly.

std::vector< TraceItemStorage >	m_item_data
	Most of the trace data is stored here.

std::vector< uint8_t >	m_item_kinds
	The TraceItemKind for each trace item encoded as uint8_t.

std::map< uint64_t, TSCRange >	m_tscs
	This map contains the TSCs of the decoded trace items.

std::optional< std::map< uint64_t, TSCRange >::iterator >	m_last_tsc
	This is the chronologically last TSC that has been added.

std::map< uint64_t, NanosecondsRange >	m_nanoseconds
	This map contains the non-interpolated nanoseconds timestamps of the decoded trace items.

std::optional< std::map< uint64_t, NanosecondsRange >::iterator >	m_last_nanoseconds = std::nullopt

std::map< uint64_t, lldb::cpu_id_t >	m_cpus

std::optional< uint64_t >	m_last_cpu
	This is the chronologically last CPU ID.

llvm::DenseMap< uint64_t, lldb::addr_t >	m_psb_offsets

std::optional< LinuxPerfZeroTscConversion >	m_tsc_conversion
	TSC -> nanos conversion utility.

ErrorStats	m_error_stats
	Statistics of all tracing errors.

EventsStats	m_events_stats
	Statistics of all tracing events.

std::chrono::milliseconds	m_total_decoding_time {0}
	Total amount of time spent decoding.

uint64_t	m_insn_count = 0
	Total number of instructions in the trace.

Detailed Description

Class holding the instructions and function call hierarchy obtained from decoding a trace, as well as a position cursor used when reverse debugging the trace.

Each decoded thread contains a cursor to the current position the user is stopped at. See Trace::GetCursorPosition for more information.

Definition at line 61 of file DecodedThread.h.

Member Typedef Documentation

◆ TSC

using lldb_private::trace_intel_pt::DecodedThread::TSC = uint64_t

Definition at line 63 of file DecodedThread.h.

Constructor & Destructor Documentation

◆ DecodedThread()

DecodedThread::DecodedThread	(	lldb::ThreadSP	thread_sp,
		const std::optional< LinuxPerfZeroTscConversion > &	tsc_conversion
	)

Definition at line 245 of file DecodedThread.cpp.

Member Function Documentation

◆ AppendCustomError()

void DecodedThread::AppendCustomError	(	llvm::StringRef	error,
		bool	fatal = `false`
	)

Append a custom decoding.

Parameters

[in]	error	The error message.
[in]	fatal	If true, then the whole decoded thread should be discarded because a fatal anomaly has been found.

Definition at line 194 of file DecodedThread.cpp.

References lldb_private::ConstString::AsCString(), CreateNewTraceItem(), lldb_private::trace_intel_pt::DecodedThread::TraceItemStorage::error, lldb::eTraceItemKindError, m_error_stats, and lldb_private::trace_intel_pt::DecodedThread::ErrorStats::RecordError().

Referenced by PSBBlockDecoder::AppendInstructionAndDetectAnomalies(), and PSBBlockDecoder::ProcessPTEventTSC().

◆ AppendError()

void DecodedThread::AppendError ( const IntelPTError & error )

Append a decoding error.

Definition at line 188 of file DecodedThread.cpp.

References lldb_private::ConstString::AsCString(), CreateNewTraceItem(), error(), lldb_private::trace_intel_pt::DecodedThread::TraceItemStorage::error, lldb::eTraceItemKindError, m_error_stats, and lldb_private::trace_intel_pt::DecodedThread::ErrorStats::RecordError().

Referenced by PSBBlockDecoder::DecodeInstructionsAndEvents(), and PSBBlockDecoder::ProcessPTEvents().

◆ AppendEvent()

void DecodedThread::AppendEvent ( lldb::TraceEvent event )

Append an event.

Definition at line 178 of file DecodedThread.cpp.

References CreateNewTraceItem(), lldb::eTraceItemKindEvent, lldb_private::trace_intel_pt::DecodedThread::TraceItemStorage::event, m_events_stats, and lldb_private::trace_intel_pt::DecodedThread::EventsStats::RecordEvent().

Referenced by NotifyCPU(), NotifySyncPoint(), NotifyTsc(), and PSBBlockDecoder::ProcessPTEvents().

◆ AppendInstruction()

void DecodedThread::AppendInstruction ( const pt_insn & insn )

Append an instruction.

Definition at line 183 of file DecodedThread.cpp.

References CreateNewTraceItem(), lldb::eTraceItemKindInstruction, lldb_private::trace_intel_pt::DecodedThread::TraceItemStorage::load_address, and m_insn_count.

Referenced by PSBBlockDecoder::AppendInstructionAndDetectAnomalies().

◆ CalculateApproximateMemoryUsage()

size_t DecodedThread::CalculateApproximateMemoryUsage ( ) const

The approximate size in bytes used by this instance, including all the already decoded instructions.

Definition at line 250 of file DecodedThread.cpp.

References m_cpus, m_item_data, m_item_kinds, m_nanoseconds, and m_tscs.

◆ CreateNewTraceItem()

DecodedThread::TraceItemStorage & DecodedThread::CreateNewTraceItem ( lldb::TraceItemKind kind )

private

Create a new trace item.

Returns: The index of the new item.

Definition at line 103 of file DecodedThread.cpp.

References m_item_data, m_item_kinds, m_last_nanoseconds, and m_last_tsc.

Referenced by AppendCustomError(), AppendError(), AppendEvent(), and AppendInstruction().

◆ GetCPUByIndex()

lldb::cpu_id_t DecodedThread::GetCPUByIndex ( uint64_t item_index ) const

Get the most recent CPU id before or at the given trace item index.

Parameters

[in] item_index The trace item index to compare with.

Returns: The requested cpu id, or LLDB_INVALID_CPU_ID if not available.

Definition at line 153 of file DecodedThread.cpp.

References LLDB_INVALID_CPU_ID, and m_cpus.

◆ GetErrorByIndex()

const char * DecodedThread::GetErrorByIndex ( uint64_t item_index ) const

Returns: The error associated with a given trace item.

Definition at line 241 of file DecodedThread.cpp.

References m_item_data.

◆ GetErrorStats()

const DecodedThread::ErrorStats & DecodedThread::GetErrorStats ( ) const

Return an object with statistics of the trace errors that happened.

Returns: The stats object of all the events.

Definition at line 232 of file DecodedThread.cpp.

References m_error_stats.

◆ GetEventByIndex()

lldb::TraceEvent DecodedThread::GetEventByIndex ( int item_index ) const

Returns: The underlying event type for the given trace item index.

Definition at line 200 of file DecodedThread.cpp.

References m_item_data.

◆ GetEventsStats()

const DecodedThread::EventsStats & DecodedThread::GetEventsStats ( ) const

Return an object with statistics of the trace events that happened.

Returns: The stats object of all the events.

Definition at line 204 of file DecodedThread.cpp.

References m_events_stats.

◆ GetInstructionLoadAddress()

lldb::addr_t DecodedThread::GetInstructionLoadAddress ( uint64_t item_index ) const

Returns: The load address of the instruction at the given index.

Definition at line 91 of file DecodedThread.cpp.

References m_item_data.

Referenced by PSBBlockAnomalyDetector::TryIdentifyInfiniteLoop().

◆ GetItemKindByIndex()

lldb::TraceItemKind DecodedThread::GetItemKindByIndex ( uint64_t item_index ) const

Returns: The trace item kind given an item index.

Definition at line 237 of file DecodedThread.cpp.

References m_item_kinds.

Referenced by PSBBlockAnomalyDetector::TryIdentifyInfiniteLoop().

◆ GetItemsCount()

uint64_t DecodedThread::GetItemsCount ( ) const

Get the total number of instruction, errors and events from the decoded trace.

Definition at line 88 of file DecodedThread.cpp.

References m_item_kinds.

Referenced by NotifyCPU(), NotifySyncPoint(), NotifyTsc(), and PSBBlockAnomalyDetector::TryIdentifyInfiniteLoop().

◆ GetNanosecondsRangeByIndex()

std::optional< DecodedThread::NanosecondsRange > DecodedThread::GetNanosecondsRangeByIndex ( uint64_t item_index )

Get a maximal range of trace items that include the given item_index that have the same nanoseconds timestamp without interpolation.

Parameters

[in] item_index The trace item index to compare with.

Returns: The requested nanoseconds range, or std::nullopt if not available.

Definition at line 167 of file DecodedThread.cpp.

References m_nanoseconds.

◆ GetSyncPointOffsetByIndex()

lldb::addr_t DecodedThread::GetSyncPointOffsetByIndex ( uint64_t item_index ) const

Returns: The PSB offset associated with the given item index.

Definition at line 96 of file DecodedThread.cpp.

References m_psb_offsets.

◆ GetThread()

ThreadSP DecodedThread::GetThread ( )

Definition at line 100 of file DecodedThread.cpp.

References m_thread_sp.

◆ GetTotalInstructionCount()

uint64_t DecodedThread::GetTotalInstructionCount ( ) const

Returns: The number of instructions in this trace (not trace items).

Definition at line 174 of file DecodedThread.cpp.

References m_insn_count.

Referenced by PSBBlockAnomalyDetector::DetectAnomaly(), and PSBBlockAnomalyDetector::RefreshPacketOffset().

◆ GetTSCRangeByIndex()

std::optional< DecodedThread::TSCRange > DecodedThread::GetTSCRangeByIndex ( uint64_t item_index ) const

Get a maximal range of trace items that include the given item_index that have the same TSC value.

Parameters

[in] item_index The trace item index to compare with.

Returns: The requested TSC range, or std::nullopt if not available.

Definition at line 159 of file DecodedThread.cpp.

References m_tscs.

◆ NotifyCPU()

void DecodedThread::NotifyCPU ( lldb::cpu_id_t cpu_id )

Notify this object that a CPU has been seen.

If this a new CPU, an event will be created.

Definition at line 145 of file DecodedThread.cpp.

References AppendEvent(), lldb::eTraceEventCPUChanged, GetItemsCount(), m_cpus, and m_last_cpu.

◆ NotifySyncPoint()

void DecodedThread::NotifySyncPoint ( lldb::addr_t psb_offset )

Notify this object that a new PSB has been seen.

Definition at line 113 of file DecodedThread.cpp.

References AppendEvent(), lldb::eTraceEventSyncPoint, GetItemsCount(), and m_psb_offsets.

Referenced by PSBBlockDecoder::DecodePSBBlock().

◆ NotifyTsc()

void DecodedThread::NotifyTsc ( TSC tsc )

Notify this object that a new tsc has been seen.

If this a new TSC, an event will be created.

Definition at line 118 of file DecodedThread.cpp.

References AppendEvent(), lldb::eTraceEventHWClockTick, GetItemsCount(), m_last_nanoseconds, m_last_tsc, m_nanoseconds, m_tsc_conversion, and m_tscs.

Referenced by PSBBlockDecoder::DecodePSBBlock(), and PSBBlockDecoder::ProcessPTEventTSC().

Member Data Documentation

◆ m_cpus

std::map<uint64_t, lldb::cpu_id_t> lldb_private::trace_intel_pt::DecodedThread::m_cpus

private

Definition at line 313 of file DecodedThread.h.

Referenced by CalculateApproximateMemoryUsage(), GetCPUByIndex(), and NotifyCPU().

◆ m_error_stats

ErrorStats lldb_private::trace_intel_pt::DecodedThread::m_error_stats

private

Statistics of all tracing errors.

Definition at line 324 of file DecodedThread.h.

Referenced by AppendCustomError(), AppendError(), and GetErrorStats().

◆ m_events_stats

EventsStats lldb_private::trace_intel_pt::DecodedThread::m_events_stats

private

Statistics of all tracing events.

Definition at line 327 of file DecodedThread.h.

Referenced by AppendEvent(), and GetEventsStats().

◆ m_insn_count

uint64_t lldb_private::trace_intel_pt::DecodedThread::m_insn_count = 0

private

Total number of instructions in the trace.

Definition at line 332 of file DecodedThread.h.

Referenced by AppendInstruction(), and GetTotalInstructionCount().

◆ m_item_data

std::vector<TraceItemStorage> lldb_private::trace_intel_pt::DecodedThread::m_item_data

private

Most of the trace data is stored here.

Definition at line 288 of file DecodedThread.h.

Referenced by CalculateApproximateMemoryUsage(), CreateNewTraceItem(), GetErrorByIndex(), GetEventByIndex(), and GetInstructionLoadAddress().

◆ m_item_kinds

std::vector<uint8_t> lldb_private::trace_intel_pt::DecodedThread::m_item_kinds

private

The TraceItemKind for each trace item encoded as uint8_t.

We don't include it in TraceItemStorage to avoid padding.

Definition at line 291 of file DecodedThread.h.

Referenced by CalculateApproximateMemoryUsage(), CreateNewTraceItem(), GetItemKindByIndex(), and GetItemsCount().

◆ m_last_cpu

std::optional<uint64_t> lldb_private::trace_intel_pt::DecodedThread::m_last_cpu

private

This is the chronologically last CPU ID.

Definition at line 315 of file DecodedThread.h.

Referenced by NotifyCPU().

◆ m_last_nanoseconds

std::optional<std::map<uint64_t, NanosecondsRange>::iterator> lldb_private::trace_intel_pt::DecodedThread::m_last_nanoseconds = std::nullopt

private

Definition at line 308 of file DecodedThread.h.

Referenced by CreateNewTraceItem(), and NotifyTsc().

◆ m_last_tsc

std::optional<std::map<uint64_t, TSCRange>::iterator> lldb_private::trace_intel_pt::DecodedThread::m_last_tsc

private

Initial value:

=

std::nullopt

This is the chronologically last TSC that has been added.

Definition at line 299 of file DecodedThread.h.

Referenced by CreateNewTraceItem(), and NotifyTsc().

◆ m_nanoseconds

std::map<uint64_t, NanosecondsRange> lldb_private::trace_intel_pt::DecodedThread::m_nanoseconds

private

This map contains the non-interpolated nanoseconds timestamps of the decoded trace items.

It maps item index -> nanoseconds, where item index is the first index at which the mapped nanoseconds first appears. We use this representation because timestamps are sporadic and we think of them as ranges.

Definition at line 306 of file DecodedThread.h.

Referenced by CalculateApproximateMemoryUsage(), GetNanosecondsRangeByIndex(), and NotifyTsc().

◆ m_psb_offsets

llvm::DenseMap<uint64_t, lldb::addr_t> lldb_private::trace_intel_pt::DecodedThread::m_psb_offsets

private

Definition at line 318 of file DecodedThread.h.

Referenced by GetSyncPointOffsetByIndex(), and NotifySyncPoint().

◆ m_thread_sp

lldb::ThreadSP lldb_private::trace_intel_pt::DecodedThread::m_thread_sp

private

When adding new members to this class, make sure to update CalculateApproximateMemoryUsage() accordingly.

Definition at line 266 of file DecodedThread.h.

Referenced by GetThread().

◆ m_total_decoding_time

std::chrono::milliseconds lldb_private::trace_intel_pt::DecodedThread::m_total_decoding_time {0}

private

Total amount of time spent decoding.

Definition at line 329 of file DecodedThread.h.

◆ m_tsc_conversion

std::optional<LinuxPerfZeroTscConversion> lldb_private::trace_intel_pt::DecodedThread::m_tsc_conversion

private

TSC -> nanos conversion utility.

Definition at line 321 of file DecodedThread.h.

Referenced by NotifyTsc().

◆ m_tscs

std::map<uint64_t, TSCRange> lldb_private::trace_intel_pt::DecodedThread::m_tscs

private

This map contains the TSCs of the decoded trace items.

It maps item index -> TSC, where item index is the first index at which the mapped TSC first appears. We use this representation because TSCs are sporadic and we can think of them as ranges.

Definition at line 297 of file DecodedThread.h.

Referenced by CalculateApproximateMemoryUsage(), GetTSCRangeByIndex(), and NotifyTsc().

The documentation for this class was generated from the following files:

Classes

Public Types

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ TSC

Constructor & Destructor Documentation

◆ DecodedThread()

Member Function Documentation

◆ AppendCustomError()

◆ AppendError()

◆ AppendEvent()

◆ AppendInstruction()

◆ CalculateApproximateMemoryUsage()

◆ CreateNewTraceItem()

◆ GetCPUByIndex()

◆ GetErrorByIndex()

◆ GetErrorStats()

◆ GetEventByIndex()

◆ GetEventsStats()

◆ GetInstructionLoadAddress()

◆ GetItemKindByIndex()

◆ GetItemsCount()

◆ GetNanosecondsRangeByIndex()

◆ GetSyncPointOffsetByIndex()

◆ GetThread()

◆ GetTotalInstructionCount()

◆ GetTSCRangeByIndex()

◆ NotifyCPU()

◆ NotifySyncPoint()

◆ NotifyTsc()

Member Data Documentation

◆ m_cpus

◆ m_error_stats

◆ m_events_stats

◆ m_insn_count

◆ m_item_data

◆ m_item_kinds

◆ m_last_cpu

◆ m_last_nanoseconds

◆ m_last_tsc

◆ m_nanoseconds

◆ m_psb_offsets

◆ m_thread_sp

◆ m_total_decoding_time

◆ m_tsc_conversion

◆ m_tscs