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/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "record_file.h"
#include <fcntl.h>
#include <string.h>
#include <sys/mman.h>
#include <unistd.h>
#include <set>
#include <vector>
#include <base/logging.h>
#include "event_fd.h"
#include "perf_event.h"
#include "record.h"
#include "utils.h"
using namespace PerfFileFormat;
std::unique_ptr<RecordFileWriter> RecordFileWriter::CreateInstance(
const std::string& filename, const perf_event_attr& event_attr,
const std::vector<std::unique_ptr<EventFd>>& event_fds) {
// Remove old perf.data to avoid file ownership problems.
if (!RemovePossibleFile(filename)) {
return nullptr;
}
FILE* fp = fopen(filename.c_str(), "web+");
if (fp == nullptr) {
PLOG(ERROR) << "failed to open record file '" << filename << "'";
return nullptr;
}
auto writer = std::unique_ptr<RecordFileWriter>(new RecordFileWriter(filename, fp));
if (!writer->WriteAttrSection(event_attr, event_fds)) {
return nullptr;
}
return writer;
}
RecordFileWriter::RecordFileWriter(const std::string& filename, FILE* fp)
: filename_(filename),
record_fp_(fp),
attr_section_offset_(0),
attr_section_size_(0),
data_section_offset_(0),
data_section_size_(0),
feature_count_(0),
current_feature_index_(0) {
}
RecordFileWriter::~RecordFileWriter() {
if (record_fp_ != nullptr) {
Close();
}
}
bool RecordFileWriter::WriteAttrSection(const perf_event_attr& event_attr,
const std::vector<std::unique_ptr<EventFd>>& event_fds) {
// Skip file header part.
if (fseek(record_fp_, sizeof(FileHeader), SEEK_SET) == -1) {
return false;
}
// Write id section.
std::vector<uint64_t> ids;
for (auto& event_fd : event_fds) {
ids.push_back(event_fd->Id());
}
long id_section_offset = ftell(record_fp_);
if (id_section_offset == -1) {
return false;
}
if (!Write(ids.data(), ids.size() * sizeof(uint64_t))) {
return false;
}
// Write attr section.
FileAttr attr;
attr.attr = event_attr;
attr.ids.offset = id_section_offset;
attr.ids.size = ids.size() * sizeof(uint64_t);
long attr_section_offset = ftell(record_fp_);
if (attr_section_offset == -1) {
return false;
}
if (!Write(&attr, sizeof(attr))) {
return false;
}
long data_section_offset = ftell(record_fp_);
if (data_section_offset == -1) {
return false;
}
attr_section_offset_ = attr_section_offset;
attr_section_size_ = sizeof(attr);
data_section_offset_ = data_section_offset;
// Save event_attr for use when reading records.
event_attr_ = event_attr;
return true;
}
bool RecordFileWriter::WriteData(const void* buf, size_t len) {
if (!Write(buf, len)) {
return false;
}
data_section_size_ += len;
return true;
}
bool RecordFileWriter::Write(const void* buf, size_t len) {
if (fwrite(buf, len, 1, record_fp_) != 1) {
PLOG(ERROR) << "failed to write to record file '" << filename_ << "'";
return false;
}
return true;
}
bool RecordFileWriter::ReadDataSection(std::vector<std::unique_ptr<Record>>* records) {
if (fflush(record_fp_) != 0) {
PLOG(ERROR) << "fflush() failed";
return false;
}
uint64_t file_size;
if (!SeekFileEnd(&file_size)) {
return false;
}
size_t mmap_len = static_cast<size_t>(file_size);
void* mmap_addr = mmap(nullptr, mmap_len, PROT_READ, MAP_SHARED, fileno(record_fp_), 0);
if (mmap_addr == MAP_FAILED) {
PLOG(ERROR) << "mmap() failed";
return false;
}
const char* data_section = reinterpret_cast<char*>(mmap_addr) + data_section_offset_;
std::vector<std::unique_ptr<Record>> result =
ReadRecordsFromBuffer(event_attr_, data_section, data_section_size_);
if (munmap(mmap_addr, mmap_len) == -1) {
PLOG(ERROR) << "munmap() failed";
return false;
}
*records = std::move(result);
return true;
}
bool RecordFileWriter::SeekFileEnd(uint64_t* file_end) {
if (fseek(record_fp_, 0, SEEK_END) == -1) {
PLOG(ERROR) << "fseek() failed";
return false;
}
long offset = ftell(record_fp_);
if (offset == -1) {
PLOG(ERROR) << "ftell() failed";
return false;
}
*file_end = static_cast<uint64_t>(offset);
return true;
}
bool RecordFileWriter::WriteFeatureHeader(size_t feature_count) {
feature_count_ = feature_count;
current_feature_index_ = 0;
uint64_t feature_header_size = feature_count * sizeof(SectionDesc);
// Reserve enough space in the record file for the feature header.
std::vector<unsigned char> zero_data(feature_header_size);
if (fseek(record_fp_, data_section_offset_ + data_section_size_, SEEK_SET) == -1) {
PLOG(ERROR) << "fseek() failed";
return false;
}
return Write(zero_data.data(), zero_data.size());
}
bool RecordFileWriter::WriteBuildIdFeature(const std::vector<BuildIdRecord>& build_id_records) {
uint64_t start_offset;
if (!WriteFeatureBegin(&start_offset)) {
return false;
}
for (auto& record : build_id_records) {
std::vector<char> data = record.BinaryFormat();
if (!Write(data.data(), data.size())) {
return false;
}
}
return WriteFeatureEnd(FEAT_BUILD_ID, start_offset);
}
bool RecordFileWriter::WriteFeatureString(int feature, const std::string& s) {
uint64_t start_offset;
if (!WriteFeatureBegin(&start_offset)) {
return false;
}
uint32_t len = static_cast<uint32_t>(ALIGN(s.size() + 1, 64));
if (!Write(&len, sizeof(len))) {
return false;
}
std::vector<char> v(len, '\0');
std::copy(s.begin(), s.end(), v.begin());
if (!Write(v.data(), v.size())) {
return false;
}
return WriteFeatureEnd(feature, start_offset);
}
bool RecordFileWriter::WriteCmdlineFeature(const std::vector<std::string>& cmdline) {
uint64_t start_offset;
if (!WriteFeatureBegin(&start_offset)) {
return false;
}
uint32_t arg_count = cmdline.size();
if (!Write(&arg_count, sizeof(arg_count))) {
return false;
}
for (auto& arg : cmdline) {
uint32_t len = static_cast<uint32_t>(ALIGN(arg.size() + 1, 64));
if (!Write(&len, sizeof(len))) {
return false;
}
std::vector<char> array(len, '\0');
std::copy(arg.begin(), arg.end(), array.begin());
if (!Write(array.data(), array.size())) {
return false;
}
}
return WriteFeatureEnd(FEAT_CMDLINE, start_offset);
}
bool RecordFileWriter::WriteBranchStackFeature() {
uint64_t start_offset;
if (!WriteFeatureBegin(&start_offset)) {
return false;
}
return WriteFeatureEnd(FEAT_BRANCH_STACK, start_offset);
}
bool RecordFileWriter::WriteFeatureBegin(uint64_t* start_offset) {
CHECK_LT(current_feature_index_, feature_count_);
if (!SeekFileEnd(start_offset)) {
return false;
}
return true;
}
bool RecordFileWriter::WriteFeatureEnd(int feature, uint64_t start_offset) {
uint64_t end_offset;
if (!SeekFileEnd(&end_offset)) {
return false;
}
SectionDesc desc;
desc.offset = start_offset;
desc.size = end_offset - start_offset;
uint64_t feature_offset = data_section_offset_ + data_section_size_;
if (fseek(record_fp_, feature_offset + current_feature_index_ * sizeof(SectionDesc), SEEK_SET) ==
-1) {
PLOG(ERROR) << "fseek() failed";
return false;
}
if (!Write(&desc, sizeof(SectionDesc))) {
return false;
}
++current_feature_index_;
features_.push_back(feature);
return true;
}
bool RecordFileWriter::WriteFileHeader() {
FileHeader header;
memset(&header, 0, sizeof(header));
memcpy(header.magic, PERF_MAGIC, sizeof(header.magic));
header.header_size = sizeof(header);
header.attr_size = sizeof(FileAttr);
header.attrs.offset = attr_section_offset_;
header.attrs.size = attr_section_size_;
header.data.offset = data_section_offset_;
header.data.size = data_section_size_;
for (auto& feature : features_) {
int i = feature / 8;
int j = feature % 8;
header.features[i] |= (1 << j);
}
if (fseek(record_fp_, 0, SEEK_SET) == -1) {
return false;
}
if (!Write(&header, sizeof(header))) {
return false;
}
return true;
}
bool RecordFileWriter::Close() {
CHECK(record_fp_ != nullptr);
bool result = true;
// Write file header. We gather enough information to write file header only after
// writing data section and feature section.
if (!WriteFileHeader()) {
result = false;
}
if (fclose(record_fp_) != 0) {
PLOG(ERROR) << "failed to close record file '" << filename_ << "'";
result = false;
}
record_fp_ = nullptr;
return result;
}