blob: fb63ad0deb54c2309e8ec905d33f9a2622e3c8c7 [file] [log] [blame]
// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <lib/zircon-internal/device/cpu-trace/perf-mon.h>
#include <zircon/types.h>
#include <cstdint>
#include <memory>
#include "buffer_reader.h"
#include "src/lib/fxl/macros.h"
namespace perfmon {
class Reader {
virtual ~Reader();
uint32_t num_traces() const { return num_traces_; }
// See |BufferReader::ticks_per_second()|.
uint64_t ticks_per_second() const {
if (buffer_reader_)
return buffer_reader_->ticks_per_second();
return 0;
// See |BufferReader::time()|.
zx_time_t time() const {
if (buffer_reader_)
return buffer_reader_->time();
return 0;
// Set the buffer we're reading to |trace_num|.
ReaderStatus SetTrace(uint32_t trace_num);
// Return a pointer to the current trace.
// Returns nullptr if no buffer has been mapped yet.
const void* GetCurrentTraceBuffer() const;
// Return the size in bytes of the current trace.
// Returns zero if no buffer has been mapped yet.
size_t GetCurrentTraceSize() const;
// Return the offset of the last record read, for error reporting purposes.
// Only valid after a call to |ReadNextRecord()|.
size_t GetLastRecordOffset() const;
// Read the next record.
// Note: To avoid unnecessary copying of larger records, the result contains
// a pointer to the record. Such pointers remain valid until the next call.
ReaderStatus ReadNextRecord(uint32_t* trace_num, SampleRecord* record);
Reader(uint32_t num_traces);
virtual bool MapBuffer(const std::string& name, uint32_t trace_num) = 0;
virtual bool UnmapBuffer() = 0;
bool BufferMapped() const { return !!buffer_reader_; }
// Utility to update |status_| and return the current value.
// The status is updated only if it is currently |kOk|.
ReaderStatus set_status(ReaderStatus status) {
if (status_ == ReaderStatus::kOk)
status_ = status;
return status_;
const uint32_t num_traces_;
uint32_t current_trace_ = 0;
std::unique_ptr<BufferReader> buffer_reader_;
// Reader status. Once we get a reader error, reading stops.
ReaderStatus status_ = ReaderStatus::kOk;
} // namespace perfmon