This class wraps a single perf event collecting intel pt data in a single buffer. More...

#include <IntelPTSingleBufferTrace.h>

Public Member Functions
llvm::Expected< std::vector< uint8_t > >	GetBinaryData (const TraceGetBinaryDataRequest &request) const
llvm::Expected< std::vector< uint8_t > >	GetIptTrace ()
	Read the intel pt trace buffer managed by this trace instance.
size_t	GetIptTraceSize () const
llvm::Error	Resume ()
	Resume the collection of this trace.
llvm::Error	Pause ()
	Pause the collection of this trace.
const PerfEvent &	GetPerfEvent () const

Static Public Member Functions
static llvm::Expected< IntelPTSingleBufferTrace >	Start (const TraceIntelPTStartRequest &request, std::optional< lldb::tid_t > tid, std::optional< lldb::cpu_id_t > cpu_id=std::nullopt, bool disabled=false, std::optional< int > cgroup_fd=std::nullopt)
	Start tracing using a single Intel PT trace buffer.

Private Member Functions
	IntelPTSingleBufferTrace (PerfEvent &&perf_event)
	Construct new IntelPTSingleBufferThreadTrace.

Private Attributes
PerfEvent	m_perf_event
	perf event configured for IntelPT.

Detailed Description

This class wraps a single perf event collecting intel pt data in a single buffer.

Definition at line 25 of file IntelPTSingleBufferTrace.h.

Constructor & Destructor Documentation

◆ IntelPTSingleBufferTrace()

lldb_private::process_linux::IntelPTSingleBufferTrace::IntelPTSingleBufferTrace ( PerfEvent && perf_event )

inlineprivate

Construct new IntelPTSingleBufferThreadTrace.

Users are supposed to create instances of this class via the Start() method and not invoke this one directly.

Parameters

[in]	perf_event	perf event configured for IntelPT.
[in]	collection_state	The initial collection state for the provided perf_event.

Definition at line 105 of file IntelPTSingleBufferTrace.h.

References m_perf_event.

Referenced by Start().

Member Function Documentation

◆ GetBinaryData()

llvm::Expected< std::vector< uint8_t > > lldb_private::process_linux::IntelPTSingleBufferTrace::GetBinaryData ( const TraceGetBinaryDataRequest & request ) const

Returns: The bytes requested by a jLLDBTraceGetBinaryData packet that was routed to this trace instace.

◆ GetIptTrace()

Expected< std::vector< uint8_t > > IntelPTSingleBufferTrace::GetIptTrace ( )

Read the intel pt trace buffer managed by this trace instance.

To ensure that the data is up-to-date and is not corrupted by read-write race conditions, the underlying perf_event is paused during read, and later it's returned to its initial state.

Returns: A vector with the requested binary data.

Definition at line 213 of file IntelPTSingleBufferTrace.cpp.

References m_perf_event.

◆ GetIptTraceSize()

size_t IntelPTSingleBufferTrace::GetIptTraceSize ( ) const

Returns: The total the size in bytes used by the intel pt trace buffer managed by this trace instance.

Definition at line 201 of file IntelPTSingleBufferTrace.cpp.

References m_perf_event.

Referenced by lldb_private::process_linux::IntelPTCollector::GetState(), lldb_private::process_linux::IntelPTMultiCoreTrace::GetState(), and lldb_private::process_linux::IntelPTPerThreadProcessTrace::GetState().

◆ GetPerfEvent()

const PerfEvent & IntelPTSingleBufferTrace::GetPerfEvent ( ) const

Returns: The underlying PerfEvent for this trace.

Definition at line 287 of file IntelPTSingleBufferTrace.cpp.

References m_perf_event.

◆ Pause()

Error IntelPTSingleBufferTrace::Pause ( )

Pause the collection of this trace.

Returns: An error if the trace couldn't be paused. If the trace is already paused, this returns Error::success().

Definition at line 205 of file IntelPTSingleBufferTrace.cpp.

References m_perf_event.

Referenced by lldb_private::process_linux::IntelPTMultiCoreTrace::ProcessDidStop().

◆ Resume()

Error IntelPTSingleBufferTrace::Resume ( )

Resume the collection of this trace.

Returns: An error if the trace couldn't be resumed. If the trace is already running, this returns Error::success().

Definition at line 209 of file IntelPTSingleBufferTrace.cpp.

References m_perf_event.

Referenced by lldb_private::process_linux::IntelPTMultiCoreTrace::ProcessWillResume().

◆ Start()

Expected< IntelPTSingleBufferTrace > IntelPTSingleBufferTrace::Start	(	const TraceIntelPTStartRequest &	request,
		std::optional< lldb::tid_t >	tid,
		std::optional< lldb::cpu_id_t >	cpu_id = std::nullopt,
		bool	disabled = false,
		std::optional< int >	cgroup_fd = std::nullopt )

static

Start tracing using a single Intel PT trace buffer.

Parameters

[in]	request	Intel PT configuration parameters.
[in]	tid	The tid of the thread to be traced. If None, then this traces all threads of all processes.
[in]	cpu_id	The CPU core id where to trace. If None, then this traces all CPUs.
[in]	disabled	If true, then no data is collected until Resume is invoked. Similarly, if false, data is collected right away until Pause is invoked.
[in]	cgroup_fd	A file descriptor in /sys/fs associated with the cgroup of the process to trace. If not std::nullopt, then the trace sesion will use cgroup filtering.