lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 1 | // Copyright (c) 2013 The Chromium OS Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #include "perf_parser.h" |
| 6 | |
| 7 | #include <fcntl.h> |
| 8 | #include <stdint.h> |
| 9 | #include <stdio.h> |
| 10 | #include <sys/stat.h> |
| 11 | #include <sys/types.h> |
| 12 | #include <unistd.h> |
lakshmana | d825e1e | 2017-11-03 10:26:31 -0700 | [diff] [blame] | 13 | #include <algorithm> |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 14 | |
| 15 | #include <memory> |
| 16 | #include <set> |
| 17 | #include <sstream> |
| 18 | |
| 19 | #include "base/logging.h" |
| 20 | |
| 21 | #include "address_mapper.h" |
| 22 | #include "binary_data_utils.h" |
| 23 | #include "compat/proto.h" |
| 24 | #include "compat/string.h" |
| 25 | #include "dso.h" |
| 26 | #include "huge_page_deducer.h" |
| 27 | |
| 28 | namespace quipper { |
| 29 | |
| 30 | using BranchStackEntry = PerfDataProto_BranchStackEntry; |
| 31 | using CommEvent = PerfDataProto_CommEvent; |
| 32 | using ForkEvent = PerfDataProto_ForkEvent; |
| 33 | using MMapEvent = PerfDataProto_MMapEvent; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 34 | using SampleEvent = PerfDataProto_SampleEvent; |
| 35 | |
| 36 | namespace { |
| 37 | |
| 38 | // MMAPs are aligned to pages of this many bytes. |
| 39 | const uint64_t kMmapPageAlignment = sysconf(_SC_PAGESIZE); |
| 40 | |
| 41 | // Name and ID of the kernel swapper process. |
| 42 | const char kSwapperCommandName[] = "swapper"; |
| 43 | const uint32_t kSwapperPid = 0; |
| 44 | |
| 45 | // Returns the offset within a page of size |kMmapPageAlignment|, given an |
| 46 | // address. Requires that |kMmapPageAlignment| be a power of 2. |
| 47 | uint64_t GetPageAlignedOffset(uint64_t addr) { |
| 48 | return addr % kMmapPageAlignment; |
| 49 | } |
| 50 | |
| 51 | bool IsNullBranchStackEntry(const BranchStackEntry& entry) { |
| 52 | return (!entry.from_ip() && !entry.to_ip()); |
| 53 | } |
| 54 | |
| 55 | } // namespace |
| 56 | |
| 57 | PerfParser::PerfParser(PerfReader* reader) : reader_(reader) {} |
| 58 | |
| 59 | PerfParser::~PerfParser() {} |
| 60 | |
| 61 | PerfParser::PerfParser(PerfReader* reader, const PerfParserOptions& options) |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 62 | : reader_(reader), options_(options) {} |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 63 | |
| 64 | bool PerfParser::ParseRawEvents() { |
| 65 | if (options_.sort_events_by_time) { |
| 66 | reader_->MaybeSortEventsByTime(); |
| 67 | } |
| 68 | |
| 69 | // Just in case there was data from a previous call. |
| 70 | process_mappers_.clear(); |
| 71 | |
ckennelly | 3a88ebd | 2017-08-31 20:46:41 +0200 | [diff] [blame] | 72 | // Find huge page mappings. |
| 73 | if (options_.deduce_huge_page_mappings) { |
vlankhaar | a6b8f1a | 2018-02-13 09:29:24 -0800 | [diff] [blame] | 74 | DeduceHugePages(reader_->mutable_events()); |
ckennelly | 3a88ebd | 2017-08-31 20:46:41 +0200 | [diff] [blame] | 75 | } |
| 76 | |
| 77 | // Combine split mappings. Because the remapping process makes addresses |
| 78 | // contiguous, we cannot try to combine mappings in these situations (as we |
| 79 | // collapse maps that were non-contiguous). |
| 80 | if (options_.combine_mappings && !options_.do_remap) { |
| 81 | CombineMappings(reader_->mutable_events()); |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 82 | } |
| 83 | |
| 84 | // Clear the parsed events to reset their fields. Otherwise, non-sample events |
| 85 | // may have residual DSO+offset info. |
| 86 | parsed_events_.clear(); |
| 87 | |
| 88 | // Events of type PERF_RECORD_FINISHED_ROUND don't have a timestamp, and are |
| 89 | // not needed. |
| 90 | // use the partial-sorting of events between rounds to sort faster. |
| 91 | parsed_events_.resize(reader_->events().size()); |
| 92 | size_t write_index = 0; |
| 93 | for (int i = 0; i < reader_->events().size(); ++i) { |
| 94 | if (reader_->events().Get(i).header().type() == PERF_RECORD_FINISHED_ROUND) |
| 95 | continue; |
| 96 | parsed_events_[write_index++].event_ptr = |
| 97 | reader_->mutable_events()->Mutable(i); |
| 98 | } |
| 99 | parsed_events_.resize(write_index); |
| 100 | |
| 101 | ProcessEvents(); |
| 102 | |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 103 | if (!options_.discard_unused_events) return true; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 104 | |
| 105 | // Some MMAP/MMAP2 events' mapped regions will not have any samples. These |
| 106 | // MMAP/MMAP2 events should be dropped. |parsed_events_| should be |
| 107 | // reconstructed without these events. |
| 108 | write_index = 0; |
| 109 | size_t read_index; |
| 110 | for (read_index = 0; read_index < parsed_events_.size(); ++read_index) { |
| 111 | const ParsedEvent& event = parsed_events_[read_index]; |
| 112 | if (event.event_ptr->has_mmap_event() && |
| 113 | event.num_samples_in_mmap_region == 0) { |
| 114 | continue; |
| 115 | } |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 116 | if (read_index != write_index) parsed_events_[write_index] = event; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 117 | ++write_index; |
| 118 | } |
| 119 | CHECK_LE(write_index, parsed_events_.size()); |
| 120 | parsed_events_.resize(write_index); |
| 121 | |
| 122 | // Update the events in |reader_| to match the updated events. |
| 123 | UpdatePerfEventsFromParsedEvents(); |
| 124 | |
| 125 | return true; |
| 126 | } |
| 127 | |
lannadorai | 91a5cde | 2018-01-18 09:38:44 -0800 | [diff] [blame] | 128 | bool PerfParser::ProcessUserEvents(PerfEvent& event) { |
| 129 | // New user events from PERF-4.13 is not yet supported |
lakshmana | 98ed13a | 2018-02-22 17:48:32 -0800 | [diff] [blame] | 130 | switch (event.header().type()) { |
| 131 | case PERF_RECORD_AUXTRACE: |
| 132 | VLOG(1) << "Parsed event type: " << event.header().type() |
| 133 | << ". Doing nothing."; |
| 134 | break; |
| 135 | default: |
| 136 | VLOG(1) << "Unsupported event type: " << event.header().type(); |
| 137 | break; |
| 138 | } |
lannadorai | 91a5cde | 2018-01-18 09:38:44 -0800 | [diff] [blame] | 139 | return true; |
| 140 | } |
| 141 | |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 142 | bool PerfParser::ProcessEvents() { |
| 143 | stats_ = {0}; |
| 144 | |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 145 | stats_.did_remap = false; // Explicitly clear the remap flag. |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 146 | |
| 147 | // Pid 0 is called the swapper process. Even though perf does not record a |
| 148 | // COMM event for pid 0, we act like we did receive a COMM event for it. Perf |
| 149 | // does this itself, example: |
| 150 | // http://lxr.free-electrons.com/source/tools/perf/util/session.c#L1120 |
| 151 | commands_.insert(kSwapperCommandName); |
| 152 | pidtid_to_comm_map_[std::make_pair(kSwapperPid, kSwapperPid)] = |
| 153 | &(*commands_.find(kSwapperCommandName)); |
| 154 | |
| 155 | // NB: Not necessarily actually sorted by time. |
| 156 | for (size_t i = 0; i < parsed_events_.size(); ++i) { |
| 157 | ParsedEvent& parsed_event = parsed_events_[i]; |
| 158 | PerfEvent& event = *parsed_event.event_ptr; |
lannadorai | 91a5cde | 2018-01-18 09:38:44 -0800 | [diff] [blame] | 159 | |
| 160 | // Process user events |
| 161 | if (event.header().type() >= PERF_RECORD_USER_TYPE_START) { |
| 162 | if (!ProcessUserEvents(event)) { |
| 163 | return false; |
| 164 | } |
| 165 | continue; |
| 166 | } |
| 167 | |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 168 | switch (event.header().type()) { |
| 169 | case PERF_RECORD_SAMPLE: |
| 170 | // SAMPLE doesn't have any fields to log at a fixed, |
| 171 | // previously-endian-swapped location. This used to log ip. |
| 172 | VLOG(1) << "SAMPLE"; |
| 173 | ++stats_.num_sample_events; |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 174 | if (MapSampleEvent(&parsed_event)) ++stats_.num_sample_events_mapped; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 175 | break; |
| 176 | case PERF_RECORD_MMAP: |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 177 | case PERF_RECORD_MMAP2: { |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 178 | const char* mmap_type_name = |
| 179 | event.header().type() == PERF_RECORD_MMAP ? "MMAP" : "MMAP2"; |
| 180 | VLOG(1) << mmap_type_name << ": " << event.mmap_event().filename(); |
| 181 | ++stats_.num_mmap_events; |
| 182 | // Use the array index of the current mmap event as a unique identifier. |
| 183 | CHECK(MapMmapEvent(event.mutable_mmap_event(), i)) |
| 184 | << "Unable to map " << mmap_type_name << " event!"; |
| 185 | // No samples in this MMAP region yet, hopefully. |
| 186 | parsed_event.num_samples_in_mmap_region = 0; |
| 187 | DSOInfo dso_info; |
| 188 | dso_info.name = event.mmap_event().filename(); |
| 189 | if (event.header().type() == PERF_RECORD_MMAP2) { |
| 190 | dso_info.maj = event.mmap_event().maj(); |
| 191 | dso_info.min = event.mmap_event().min(); |
| 192 | dso_info.ino = event.mmap_event().ino(); |
| 193 | } |
| 194 | name_to_dso_.emplace(dso_info.name, dso_info); |
| 195 | break; |
| 196 | } |
| 197 | case PERF_RECORD_FORK: |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 198 | // clang-format off |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 199 | VLOG(1) << "FORK: " << event.fork_event().ppid() |
| 200 | << ":" << event.fork_event().ptid() |
| 201 | << " -> " << event.fork_event().pid() |
| 202 | << ":" << event.fork_event().tid(); |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 203 | // clang-format on |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 204 | ++stats_.num_fork_events; |
| 205 | CHECK(MapForkEvent(event.fork_event())) << "Unable to map FORK event!"; |
| 206 | break; |
| 207 | case PERF_RECORD_EXIT: |
| 208 | // EXIT events have the same structure as FORK events. |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 209 | // clang-format off |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 210 | VLOG(1) << "EXIT: " << event.fork_event().ppid() |
| 211 | << ":" << event.fork_event().ptid(); |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 212 | // clang-format on |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 213 | ++stats_.num_exit_events; |
| 214 | break; |
| 215 | case PERF_RECORD_COMM: |
| 216 | { |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 217 | // clang-format off |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 218 | VLOG(1) << "COMM: " << event.comm_event().pid() |
| 219 | << ":" << event.comm_event().tid() << ": " |
| 220 | << event.comm_event().comm(); |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 221 | // clang-format on |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 222 | ++stats_.num_comm_events; |
| 223 | CHECK(MapCommEvent(event.comm_event())); |
| 224 | commands_.insert(event.comm_event().comm()); |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 225 | const PidTid pidtid = |
| 226 | std::make_pair(event.comm_event().pid(), event.comm_event().tid()); |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 227 | pidtid_to_comm_map_[pidtid] = |
| 228 | &(*commands_.find(event.comm_event().comm())); |
| 229 | break; |
| 230 | } |
| 231 | case PERF_RECORD_LOST: |
| 232 | case PERF_RECORD_THROTTLE: |
| 233 | case PERF_RECORD_UNTHROTTLE: |
| 234 | case PERF_RECORD_READ: |
lakshmana | 98ed13a | 2018-02-22 17:48:32 -0800 | [diff] [blame] | 235 | case PERF_RECORD_AUX: |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 236 | VLOG(1) << "Parsed event type: " << event.header().type() |
| 237 | << ". Doing nothing."; |
| 238 | break; |
lannadorai | 91a5cde | 2018-01-18 09:38:44 -0800 | [diff] [blame] | 239 | case PERF_RECORD_ITRACE_START: |
| 240 | case PERF_RECORD_LOST_SAMPLES: |
| 241 | case PERF_RECORD_SWITCH: |
| 242 | case PERF_RECORD_SWITCH_CPU_WIDE: |
| 243 | case PERF_RECORD_NAMESPACES: |
| 244 | VLOG(1) << "Parsed event type: " << event.header().type() |
| 245 | << ". Not yet supported."; |
| 246 | break; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 247 | default: |
| 248 | LOG(ERROR) << "Unknown event type: " << event.header().type(); |
| 249 | return false; |
| 250 | } |
| 251 | } |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 252 | if (!FillInDsoBuildIds()) return false; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 253 | |
| 254 | // Print stats collected from parsing. |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 255 | // clang-format off |
Andreas Gampe | 77162c9 | 2018-03-15 20:42:10 -0700 | [diff] [blame] | 256 | VLOG(1) << "Parser processed: " |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 257 | << stats_.num_mmap_events << " MMAP/MMAP2 events, " |
| 258 | << stats_.num_comm_events << " COMM events, " |
| 259 | << stats_.num_fork_events << " FORK events, " |
| 260 | << stats_.num_exit_events << " EXIT events, " |
| 261 | << stats_.num_sample_events << " SAMPLE events, " |
| 262 | << stats_.num_sample_events_mapped << " of these were mapped"; |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 263 | // clang-format on |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 264 | |
| 265 | float sample_mapping_percentage = |
| 266 | static_cast<float>(stats_.num_sample_events_mapped) / |
| 267 | stats_.num_sample_events * 100.; |
| 268 | float threshold = options_.sample_mapping_percentage_threshold; |
| 269 | if (sample_mapping_percentage < threshold) { |
| 270 | LOG(ERROR) << "Mapped " << static_cast<int>(sample_mapping_percentage) |
| 271 | << "% of samples, expected at least " |
| 272 | << static_cast<int>(threshold) << "%"; |
| 273 | return false; |
| 274 | } |
| 275 | stats_.did_remap = options_.do_remap; |
| 276 | return true; |
| 277 | } |
| 278 | |
| 279 | namespace { |
| 280 | |
| 281 | class FdCloser { |
| 282 | public: |
| 283 | explicit FdCloser(int fd) : fd_(fd) {} |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 284 | ~FdCloser() { |
| 285 | if (fd_ != -1) close(fd_); |
| 286 | } |
| 287 | |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 288 | private: |
| 289 | FdCloser() = delete; |
| 290 | FdCloser(FdCloser&) = delete; |
| 291 | |
| 292 | int fd_; |
| 293 | }; |
| 294 | |
lakshmana | d825e1e | 2017-11-03 10:26:31 -0700 | [diff] [blame] | 295 | // Merges two uint32_t into a uint64_t for hashing in an unordered_set because |
| 296 | // there is no default hash method for a pair. |
| 297 | uint64_t mergeTwoU32(uint32_t first, uint32_t second) { |
| 298 | return (uint64_t)first << 32 | second; |
| 299 | } |
| 300 | |
| 301 | // Splits a given uint64_t into two uint32_t. This reverts the above merge |
| 302 | // operation to retrieve the two uint32_t from an unordered_set. |
| 303 | std::pair<uint32_t, uint32_t> splitU64(uint64_t value) { |
| 304 | return std::make_pair(value >> 32, |
| 305 | std::numeric_limits<uint32_t>::max() & value); |
| 306 | } |
| 307 | |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 308 | bool ReadElfBuildIdIfSameInode(const string& dso_path, const DSOInfo& dso, |
| 309 | string* buildid) { |
| 310 | int fd = open(dso_path.c_str(), O_RDONLY); |
| 311 | FdCloser fd_closer(fd); |
| 312 | if (fd == -1) { |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 313 | if (errno != ENOENT) LOG(ERROR) << "Failed to open ELF file: " << dso_path; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 314 | return false; |
| 315 | } |
| 316 | |
| 317 | struct stat s; |
| 318 | CHECK_GE(fstat(fd, &s), 0); |
| 319 | // Only reject based on inode if we actually have device info (from MMAP2). |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 320 | if (dso.maj != 0 && dso.min != 0 && !SameInode(dso, &s)) return false; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 321 | |
| 322 | return ReadElfBuildId(fd, buildid); |
| 323 | } |
| 324 | |
| 325 | // Looks up build ID of a given DSO by reading directly from the file system. |
| 326 | // - Does not support reading build ID of the main kernel binary. |
| 327 | // - Reads build IDs of kernel modules and other DSOs using functions in dso.h. |
| 328 | string FindDsoBuildId(const DSOInfo& dso_info) { |
| 329 | string buildid_bin; |
| 330 | const string& dso_name = dso_info.name; |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 331 | if (IsKernelNonModuleName(dso_name)) return buildid_bin; // still empty |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 332 | // Does this look like a kernel module? |
| 333 | if (dso_name.size() >= 2 && dso_name[0] == '[' && dso_name.back() == ']') { |
| 334 | // This may not be successful, but either way, just return. buildid_bin |
| 335 | // will be empty if the module was not found. |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 336 | ReadModuleBuildId(dso_name.substr(1, dso_name.size() - 2), &buildid_bin); |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 337 | return buildid_bin; |
| 338 | } |
| 339 | // Try normal files, possibly inside containers. |
| 340 | u32 last_pid = 0; |
lakshmana | d825e1e | 2017-11-03 10:26:31 -0700 | [diff] [blame] | 341 | std::vector<uint64_t> threads(dso_info.threads.begin(), |
| 342 | dso_info.threads.end()); |
| 343 | std::sort(threads.begin(), threads.end()); |
| 344 | for (auto pidtid_it : threads) { |
| 345 | uint32_t pid, tid; |
| 346 | std::tie(pid, tid) = splitU64(pidtid_it); |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 347 | std::stringstream dso_path_stream; |
| 348 | dso_path_stream << "/proc/" << tid << "/root/" << dso_name; |
| 349 | string dso_path = dso_path_stream.str(); |
| 350 | if (ReadElfBuildIdIfSameInode(dso_path, dso_info, &buildid_bin)) { |
| 351 | return buildid_bin; |
| 352 | } |
| 353 | // Avoid re-trying the parent process if it's the same for multiple threads. |
| 354 | // dso_info.threads is sorted, so threads in a process should be adjacent. |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 355 | if (pid == last_pid || pid == tid) continue; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 356 | last_pid = pid; |
| 357 | // Try the parent process: |
| 358 | std::stringstream parent_dso_path_stream; |
| 359 | parent_dso_path_stream << "/proc/" << pid << "/root/" << dso_name; |
| 360 | string parent_dso_path = parent_dso_path_stream.str(); |
| 361 | if (ReadElfBuildIdIfSameInode(parent_dso_path, dso_info, &buildid_bin)) { |
| 362 | return buildid_bin; |
| 363 | } |
| 364 | } |
| 365 | // Still don't have a buildid. Try our own filesystem: |
| 366 | if (ReadElfBuildIdIfSameInode(dso_name, dso_info, &buildid_bin)) { |
| 367 | return buildid_bin; |
| 368 | } |
| 369 | return buildid_bin; // still empty. |
| 370 | } |
| 371 | |
| 372 | } // namespace |
| 373 | |
| 374 | bool PerfParser::FillInDsoBuildIds() { |
| 375 | std::map<string, string> filenames_to_build_ids; |
| 376 | reader_->GetFilenamesToBuildIDs(&filenames_to_build_ids); |
| 377 | |
| 378 | std::map<string, string> new_buildids; |
| 379 | |
| 380 | for (std::pair<const string, DSOInfo>& kv : name_to_dso_) { |
| 381 | DSOInfo& dso_info = kv.second; |
| 382 | const auto it = filenames_to_build_ids.find(dso_info.name); |
| 383 | if (it != filenames_to_build_ids.end()) { |
| 384 | dso_info.build_id = it->second; |
| 385 | } |
| 386 | // If there is both an existing build ID and a new build ID returned by |
| 387 | // FindDsoBuildId(), overwrite the existing build ID. |
| 388 | if (options_.read_missing_buildids && dso_info.hit) { |
| 389 | string buildid_bin = FindDsoBuildId(dso_info); |
| 390 | if (!buildid_bin.empty()) { |
| 391 | dso_info.build_id = RawDataToHexString(buildid_bin); |
| 392 | new_buildids[dso_info.name] = dso_info.build_id; |
| 393 | } |
| 394 | } |
| 395 | } |
| 396 | |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 397 | if (new_buildids.empty()) return true; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 398 | return reader_->InjectBuildIDs(new_buildids); |
| 399 | } |
| 400 | |
| 401 | void PerfParser::UpdatePerfEventsFromParsedEvents() { |
| 402 | // Reorder the events in |reader_| to match the order of |parsed_events_|. |
| 403 | // The |event_ptr|'s in |parsed_events_| are pointers to existing events in |
| 404 | // |reader_|. |
| 405 | RepeatedPtrField<PerfEvent> new_events; |
| 406 | new_events.Reserve(parsed_events_.size()); |
| 407 | for (ParsedEvent& parsed_event : parsed_events_) { |
| 408 | PerfEvent* new_event = new_events.Add(); |
| 409 | new_event->Swap(parsed_event.event_ptr); |
| 410 | parsed_event.event_ptr = new_event; |
| 411 | } |
| 412 | |
| 413 | reader_->mutable_events()->Swap(&new_events); |
| 414 | } |
| 415 | |
| 416 | bool PerfParser::MapSampleEvent(ParsedEvent* parsed_event) { |
| 417 | bool mapping_failed = false; |
| 418 | |
| 419 | const PerfEvent& event = *parsed_event->event_ptr; |
| 420 | if (!event.has_sample_event() || |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 421 | !(event.sample_event().has_ip() && event.sample_event().has_pid() && |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 422 | event.sample_event().has_tid())) { |
| 423 | return false; |
| 424 | } |
| 425 | SampleEvent& sample_info = *parsed_event->event_ptr->mutable_sample_event(); |
| 426 | |
| 427 | // Find the associated command. |
| 428 | PidTid pidtid = std::make_pair(sample_info.pid(), sample_info.tid()); |
| 429 | const auto comm_iter = pidtid_to_comm_map_.find(pidtid); |
| 430 | if (comm_iter != pidtid_to_comm_map_.end()) |
| 431 | parsed_event->set_command(comm_iter->second); |
| 432 | |
| 433 | const uint64_t unmapped_event_ip = sample_info.ip(); |
| 434 | uint64_t remapped_event_ip = 0; |
| 435 | |
| 436 | // Map the event IP itself. |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 437 | if (!MapIPAndPidAndGetNameAndOffset(sample_info.ip(), pidtid, |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 438 | &remapped_event_ip, |
| 439 | &parsed_event->dso_and_offset)) { |
| 440 | mapping_failed = true; |
| 441 | } else { |
| 442 | sample_info.set_ip(remapped_event_ip); |
| 443 | } |
| 444 | |
| 445 | if (sample_info.callchain_size() && |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 446 | !MapCallchain(sample_info.ip(), pidtid, unmapped_event_ip, |
| 447 | sample_info.mutable_callchain(), parsed_event)) { |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 448 | mapping_failed = true; |
| 449 | } |
| 450 | |
| 451 | if (sample_info.branch_stack_size() && |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 452 | !MapBranchStack(pidtid, sample_info.mutable_branch_stack(), |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 453 | parsed_event)) { |
| 454 | mapping_failed = true; |
| 455 | } |
| 456 | |
| 457 | return !mapping_failed; |
| 458 | } |
| 459 | |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 460 | bool PerfParser::MapCallchain(const uint64_t ip, const PidTid pidtid, |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 461 | const uint64_t original_event_addr, |
| 462 | RepeatedField<uint64>* callchain, |
| 463 | ParsedEvent* parsed_event) { |
| 464 | if (!callchain) { |
| 465 | LOG(ERROR) << "NULL call stack data."; |
| 466 | return false; |
| 467 | } |
| 468 | |
| 469 | bool mapping_failed = false; |
| 470 | |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 471 | // If the callchain is empty, there is no work to do. |
| 472 | if (callchain->empty()) return true; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 473 | |
| 474 | // Keeps track of whether the current entry is kernel or user. |
| 475 | parsed_event->callchain.resize(callchain->size()); |
| 476 | int num_entries_mapped = 0; |
| 477 | for (int i = 0; i < callchain->size(); ++i) { |
| 478 | uint64_t entry = callchain->Get(i); |
| 479 | // When a callchain context entry is found, do not attempt to symbolize it. |
| 480 | if (entry >= PERF_CONTEXT_MAX) { |
| 481 | continue; |
| 482 | } |
| 483 | // The sample address has already been mapped so no need to map it. |
| 484 | if (entry == original_event_addr) { |
| 485 | callchain->Set(i, ip); |
| 486 | continue; |
| 487 | } |
| 488 | uint64_t mapped_addr = 0; |
| 489 | if (!MapIPAndPidAndGetNameAndOffset( |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 490 | entry, pidtid, &mapped_addr, |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 491 | &parsed_event->callchain[num_entries_mapped++])) { |
| 492 | mapping_failed = true; |
| 493 | } else { |
| 494 | callchain->Set(i, mapped_addr); |
| 495 | } |
| 496 | } |
| 497 | // Not all the entries were mapped. Trim |parsed_event->callchain| to |
| 498 | // remove unused entries at the end. |
| 499 | parsed_event->callchain.resize(num_entries_mapped); |
| 500 | |
| 501 | return !mapping_failed; |
| 502 | } |
| 503 | |
| 504 | bool PerfParser::MapBranchStack( |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 505 | const PidTid pidtid, RepeatedPtrField<BranchStackEntry>* branch_stack, |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 506 | ParsedEvent* parsed_event) { |
| 507 | if (!branch_stack) { |
| 508 | LOG(ERROR) << "NULL branch stack data."; |
| 509 | return false; |
| 510 | } |
| 511 | |
| 512 | // First, trim the branch stack to remove trailing null entries. |
| 513 | size_t trimmed_size = 0; |
| 514 | for (const BranchStackEntry& entry : *branch_stack) { |
| 515 | // Count the number of non-null entries before the first null entry. |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 516 | if (IsNullBranchStackEntry(entry)) break; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 517 | ++trimmed_size; |
| 518 | } |
| 519 | |
| 520 | // If a null entry was found, make sure all subsequent null entries are NULL |
| 521 | // as well. |
| 522 | for (int i = trimmed_size; i < branch_stack->size(); ++i) { |
| 523 | const BranchStackEntry& entry = branch_stack->Get(i); |
| 524 | if (!IsNullBranchStackEntry(entry)) { |
| 525 | LOG(ERROR) << "Non-null branch stack entry found after null entry: " |
| 526 | << reinterpret_cast<void*>(entry.from_ip()) << " -> " |
| 527 | << reinterpret_cast<void*>(entry.to_ip()); |
| 528 | return false; |
| 529 | } |
| 530 | } |
| 531 | |
| 532 | // Map branch stack addresses. |
| 533 | parsed_event->branch_stack.resize(trimmed_size); |
| 534 | for (unsigned int i = 0; i < trimmed_size; ++i) { |
| 535 | BranchStackEntry* entry = branch_stack->Mutable(i); |
| 536 | ParsedEvent::BranchEntry& parsed_entry = parsed_event->branch_stack[i]; |
| 537 | |
| 538 | uint64_t from_mapped = 0; |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 539 | if (!MapIPAndPidAndGetNameAndOffset(entry->from_ip(), pidtid, &from_mapped, |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 540 | &parsed_entry.from)) { |
| 541 | return false; |
| 542 | } |
| 543 | entry->set_from_ip(from_mapped); |
| 544 | |
| 545 | uint64_t to_mapped = 0; |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 546 | if (!MapIPAndPidAndGetNameAndOffset(entry->to_ip(), pidtid, &to_mapped, |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 547 | &parsed_entry.to)) { |
| 548 | return false; |
| 549 | } |
| 550 | entry->set_to_ip(to_mapped); |
| 551 | |
| 552 | parsed_entry.predicted = !entry->mispredicted(); |
| 553 | } |
| 554 | |
| 555 | return true; |
| 556 | } |
| 557 | |
| 558 | bool PerfParser::MapIPAndPidAndGetNameAndOffset( |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 559 | uint64_t ip, PidTid pidtid, uint64_t* new_ip, |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 560 | ParsedEvent::DSOAndOffset* dso_and_offset) { |
| 561 | DCHECK(dso_and_offset); |
| 562 | // Attempt to find the synthetic address of the IP sample in this order: |
| 563 | // 1. Address space of the kernel. |
| 564 | // 2. Address space of its own process. |
| 565 | // 3. Address space of the parent process. |
| 566 | |
| 567 | uint64_t mapped_addr = 0; |
| 568 | |
| 569 | // Sometimes the first event we see is a SAMPLE event and we don't have the |
| 570 | // time to create an address mapper for a process. Example, for pid 0. |
| 571 | AddressMapper* mapper = GetOrCreateProcessMapper(pidtid.first).first; |
lakshmana | d1d18fc | 2017-11-03 12:33:31 -0700 | [diff] [blame] | 572 | AddressMapper::MappingList::const_iterator ip_iter; |
| 573 | bool mapped = |
| 574 | mapper->GetMappedAddressAndListIterator(ip, &mapped_addr, &ip_iter); |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 575 | if (mapped) { |
| 576 | uint64_t id = UINT64_MAX; |
lakshmana | d1d18fc | 2017-11-03 12:33:31 -0700 | [diff] [blame] | 577 | mapper->GetMappedIDAndOffset(ip, ip_iter, &id, &dso_and_offset->offset_); |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 578 | // Make sure the ID points to a valid event. |
| 579 | CHECK_LE(id, parsed_events_.size()); |
| 580 | ParsedEvent& parsed_event = parsed_events_[id]; |
| 581 | const auto& event = parsed_event.event_ptr; |
| 582 | DCHECK(event->has_mmap_event()) << "Expected MMAP or MMAP2 event"; |
| 583 | |
| 584 | // Find the mmap DSO filename in the set of known DSO names. |
| 585 | auto dso_iter = name_to_dso_.find(event->mmap_event().filename()); |
| 586 | CHECK(dso_iter != name_to_dso_.end()); |
| 587 | dso_and_offset->dso_info_ = &dso_iter->second; |
| 588 | |
| 589 | dso_iter->second.hit = true; |
lakshmana | d825e1e | 2017-11-03 10:26:31 -0700 | [diff] [blame] | 590 | dso_iter->second.threads.insert(mergeTwoU32(pidtid.first, pidtid.second)); |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 591 | ++parsed_event.num_samples_in_mmap_region; |
| 592 | |
| 593 | if (options_.do_remap) { |
| 594 | if (GetPageAlignedOffset(mapped_addr) != GetPageAlignedOffset(ip)) { |
| 595 | LOG(ERROR) << "Remapped address " << std::hex << mapped_addr << " " |
| 596 | << "does not have the same page alignment offset as " |
| 597 | << "original address " << ip; |
| 598 | return false; |
| 599 | } |
| 600 | *new_ip = mapped_addr; |
| 601 | } else { |
| 602 | *new_ip = ip; |
| 603 | } |
| 604 | } |
| 605 | return mapped; |
| 606 | } |
| 607 | |
| 608 | bool PerfParser::MapMmapEvent(PerfDataProto_MMapEvent* event, uint64_t id) { |
| 609 | // We need to hide only the real kernel addresses. However, to make things |
| 610 | // more secure, and make the mapping idempotent, we should remap all |
| 611 | // addresses, both kernel and non-kernel. |
| 612 | |
| 613 | AddressMapper* mapper = GetOrCreateProcessMapper(event->pid()).first; |
| 614 | |
| 615 | uint64_t start = event->start(); |
| 616 | uint64_t len = event->len(); |
| 617 | uint64_t pgoff = event->pgoff(); |
| 618 | |
| 619 | // |id| == 0 corresponds to the kernel mmap. We have several cases here: |
| 620 | // |
| 621 | // For ARM and x86, in sudo mode, pgoff == start, example: |
| 622 | // start=0x80008200 |
| 623 | // pgoff=0x80008200 |
| 624 | // len =0xfffffff7ff7dff |
| 625 | // |
| 626 | // For x86-64, in sudo mode, pgoff is between start and start + len. SAMPLE |
| 627 | // events lie between pgoff and pgoff + length of the real kernel binary, |
| 628 | // example: |
| 629 | // start=0x3bc00000 |
| 630 | // pgoff=0xffffffffbcc00198 |
| 631 | // len =0xffffffff843fffff |
| 632 | // SAMPLE events will be found after pgoff. For kernels with ASLR, pgoff will |
| 633 | // be something only visible to the root user, and will be randomized at |
| 634 | // startup. With |remap| set to true, we should hide pgoff in this case. So we |
| 635 | // normalize all SAMPLE events relative to pgoff. |
| 636 | // |
| 637 | // For non-sudo mode, the kernel will be mapped from 0 to the pointer limit, |
| 638 | // example: |
| 639 | // start=0x0 |
| 640 | // pgoff=0x0 |
| 641 | // len =0xffffffff |
| 642 | if (id == 0) { |
| 643 | // If pgoff is between start and len, we normalize the event by setting |
| 644 | // start to be pgoff just like how it is for ARM and x86. We also set len to |
| 645 | // be a much smaller number (closer to the real length of the kernel binary) |
| 646 | // because SAMPLEs are actually only seen between |event->pgoff| and |
| 647 | // |event->pgoff + kernel text size|. |
| 648 | if (pgoff > start && pgoff < start + len) { |
| 649 | len = len + start - pgoff; |
| 650 | start = pgoff; |
| 651 | } |
| 652 | // For kernels with ALSR pgoff is critical information that should not be |
| 653 | // revealed when |remap| is true. |
| 654 | pgoff = 0; |
| 655 | } |
| 656 | |
| 657 | if (!mapper->MapWithID(start, len, id, pgoff, true)) { |
| 658 | mapper->DumpToLog(); |
| 659 | return false; |
| 660 | } |
| 661 | |
| 662 | if (options_.do_remap) { |
| 663 | uint64_t mapped_addr; |
lakshmana | d1d18fc | 2017-11-03 12:33:31 -0700 | [diff] [blame] | 664 | AddressMapper::MappingList::const_iterator start_iter; |
| 665 | if (!mapper->GetMappedAddressAndListIterator(start, &mapped_addr, |
| 666 | &start_iter)) { |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 667 | LOG(ERROR) << "Failed to map starting address " << std::hex << start; |
| 668 | return false; |
| 669 | } |
| 670 | if (GetPageAlignedOffset(mapped_addr) != GetPageAlignedOffset(start)) { |
| 671 | LOG(ERROR) << "Remapped address " << std::hex << mapped_addr << " " |
| 672 | << "does not have the same page alignment offset as start " |
| 673 | << "address " << start; |
| 674 | return false; |
| 675 | } |
| 676 | |
| 677 | event->set_start(mapped_addr); |
| 678 | event->set_len(len); |
| 679 | event->set_pgoff(pgoff); |
| 680 | } |
| 681 | return true; |
| 682 | } |
| 683 | |
| 684 | bool PerfParser::MapCommEvent(const PerfDataProto_CommEvent& event) { |
| 685 | GetOrCreateProcessMapper(event.pid()); |
| 686 | return true; |
| 687 | } |
| 688 | |
| 689 | bool PerfParser::MapForkEvent(const PerfDataProto_ForkEvent& event) { |
| 690 | PidTid parent = std::make_pair(event.ppid(), event.ptid()); |
| 691 | PidTid child = std::make_pair(event.pid(), event.tid()); |
| 692 | if (parent != child) { |
| 693 | auto parent_iter = pidtid_to_comm_map_.find(parent); |
| 694 | if (parent_iter != pidtid_to_comm_map_.end()) |
| 695 | pidtid_to_comm_map_[child] = parent_iter->second; |
| 696 | } |
| 697 | |
| 698 | const uint32_t pid = event.pid(); |
| 699 | |
| 700 | // If the parent and child pids are the same, this is just a new thread |
| 701 | // within the same process, so don't do anything. |
lakshmana | 3fa0a5f | 2018-02-08 12:20:56 -0800 | [diff] [blame] | 702 | if (event.ppid() == pid) return true; |
lakshmana | 5d24e0b | 2017-08-14 14:18:43 -0700 | [diff] [blame] | 703 | |
| 704 | if (!GetOrCreateProcessMapper(pid, event.ppid()).second) { |
| 705 | DVLOG(1) << "Found an existing process mapper with pid: " << pid; |
| 706 | } |
| 707 | |
| 708 | return true; |
| 709 | } |
| 710 | |
| 711 | std::pair<AddressMapper*, bool> PerfParser::GetOrCreateProcessMapper( |
| 712 | uint32_t pid, uint32_t ppid) { |
| 713 | const auto& search = process_mappers_.find(pid); |
| 714 | if (search != process_mappers_.end()) { |
| 715 | return std::make_pair(search->second.get(), false); |
| 716 | } |
| 717 | |
| 718 | auto parent_mapper = process_mappers_.find(ppid); |
| 719 | // Recent perf implementations (at least as recent as perf 4.4), add an |
| 720 | // explicit FORK event from the swapper process to the init process. There may |
| 721 | // be no explicit memory mappings created for the swapper process. In such |
| 722 | // cases, we must use the mappings from the kernel process, which are used by |
| 723 | // default for a new PID in the absence of an explicit FORK event. |
| 724 | if (parent_mapper == process_mappers_.end()) { |
| 725 | parent_mapper = process_mappers_.find(kKernelPid); |
| 726 | } |
| 727 | std::unique_ptr<AddressMapper> mapper; |
| 728 | if (parent_mapper != process_mappers_.end()) { |
| 729 | mapper.reset(new AddressMapper(*parent_mapper->second)); |
| 730 | } else { |
| 731 | mapper.reset(new AddressMapper()); |
| 732 | mapper->set_page_alignment(kMmapPageAlignment); |
| 733 | } |
| 734 | |
| 735 | const auto inserted = |
| 736 | process_mappers_.insert(search, std::make_pair(pid, std::move(mapper))); |
| 737 | return std::make_pair(inserted->second.get(), true); |
| 738 | } |
| 739 | |
| 740 | } // namespace quipper |