1 perf.data format 1 perf.data format
2 2
3 Uptodate as of v4.7 3 Uptodate as of v4.7
4 4
5 This document describes the on-disk perf.data 5 This document describes the on-disk perf.data format, generated by perf record
6 or perf inject and consumed by the other perf 6 or perf inject and consumed by the other perf tools.
7 7
8 On a high level perf.data contains the events 8 On a high level perf.data contains the events generated by the PMUs, plus metadata.
9 9
10 All fields are in native-endian of the machine 10 All fields are in native-endian of the machine that generated the perf.data.
11 11
12 When perf is writing to a pipe it uses a speci 12 When perf is writing to a pipe it uses a special version of the file
13 format that does not rely on seeking to adjust 13 format that does not rely on seeking to adjust data offsets. This
14 format is described in "Pipe-mode data" sectio 14 format is described in "Pipe-mode data" section. The pipe data version can be
15 augmented with additional events using perf in 15 augmented with additional events using perf inject.
16 16
17 The file starts with a perf_header: 17 The file starts with a perf_header:
18 18
19 struct perf_header { 19 struct perf_header {
20 char magic[8]; /* PERFILE2 */ 20 char magic[8]; /* PERFILE2 */
21 uint64_t size; /* size of the 21 uint64_t size; /* size of the header */
22 uint64_t attr_size; /* size of an 22 uint64_t attr_size; /* size of an attribute in attrs */
23 struct perf_file_section attrs; 23 struct perf_file_section attrs;
24 struct perf_file_section data; 24 struct perf_file_section data;
25 struct perf_file_section event_types; 25 struct perf_file_section event_types;
26 uint64_t flags; 26 uint64_t flags;
27 uint64_t flags1[3]; 27 uint64_t flags1[3];
28 }; 28 };
29 29
30 The magic number identifies the perf file and 30 The magic number identifies the perf file and the version. Current perf versions
31 use PERFILE2. Old perf versions generated a ve 31 use PERFILE2. Old perf versions generated a version 1 format (PERFFILE). Version 1
32 is not described here. The magic number also i 32 is not described here. The magic number also identifies the endian. When the
33 magic value is 64bit byte swapped compared the 33 magic value is 64bit byte swapped compared the file is in non-native
34 endian. 34 endian.
35 35
36 A perf_file_section contains a pointer to anot 36 A perf_file_section contains a pointer to another section of the perf file.
37 The header contains three such pointers: for a 37 The header contains three such pointers: for attributes, data and event types.
38 38
39 struct perf_file_section { 39 struct perf_file_section {
40 uint64_t offset; /* offset from 40 uint64_t offset; /* offset from start of file */
41 uint64_t size; /* size of the 41 uint64_t size; /* size of the section */
42 }; 42 };
43 43
44 Flags section: 44 Flags section:
45 45
46 For each of the optional features a perf_file_ !! 46 The header is followed by different optional headers, described by the bits set
47 section if the feature bit is set in the perf_ !! 47 in flags. Only headers for which the bit is set are included. Each header
48 respective perf_file_section points to the dat !! 48 consists of a perf_file_section located after the initial header.
49 defines its size. !! 49 The respective perf_file_section points to the data of the additional
>> 50 header and defines its size.
50 51
51 Some headers consist of strings, which are def 52 Some headers consist of strings, which are defined like this:
52 53
53 struct perf_header_string { 54 struct perf_header_string {
54 uint32_t len; 55 uint32_t len;
55 char string[len]; /* zero terminated */ 56 char string[len]; /* zero terminated */
56 }; 57 };
57 58
58 Some headers consist of a sequence of strings, 59 Some headers consist of a sequence of strings, which start with a
59 60
60 struct perf_header_string_list { 61 struct perf_header_string_list {
61 uint32_t nr; 62 uint32_t nr;
62 struct perf_header_string strings[nr]; /* 63 struct perf_header_string strings[nr]; /* variable length records */
63 }; 64 };
64 65
65 The bits are the flags bits in a 256 bit bitma 66 The bits are the flags bits in a 256 bit bitmap starting with
66 flags. These define the valid bits: 67 flags. These define the valid bits:
67 68
68 HEADER_RESERVED = 0, /* alw 69 HEADER_RESERVED = 0, /* always cleared */
69 HEADER_FIRST_FEATURE = 1, 70 HEADER_FIRST_FEATURE = 1,
70 HEADER_TRACING_DATA = 1, 71 HEADER_TRACING_DATA = 1,
71 72
72 Describe me. 73 Describe me.
73 74
74 HEADER_BUILD_ID = 2, 75 HEADER_BUILD_ID = 2,
75 76
76 The header consists of an sequence of build_id 77 The header consists of an sequence of build_id_event. The size of each record
77 is defined by header.size (see perf_event.h). 78 is defined by header.size (see perf_event.h). Each event defines a ELF build id
78 for a executable file name for a pid. An ELF b 79 for a executable file name for a pid. An ELF build id is a unique identifier
79 assigned by the linker to an executable. 80 assigned by the linker to an executable.
80 81
81 struct build_id_event { 82 struct build_id_event {
82 struct perf_event_header header; 83 struct perf_event_header header;
83 pid_t pid; 84 pid_t pid;
84 uint8_t build_id[24]; 85 uint8_t build_id[24];
85 char filename[head 86 char filename[header.size - offsetof(struct build_id_event, filename)];
86 }; 87 };
87 88
88 HEADER_HOSTNAME = 3, 89 HEADER_HOSTNAME = 3,
89 90
90 A perf_header_string with the hostname where t 91 A perf_header_string with the hostname where the data was collected
91 (uname -n) 92 (uname -n)
92 93
93 HEADER_OSRELEASE = 4, 94 HEADER_OSRELEASE = 4,
94 95
95 A perf_header_string with the os release where 96 A perf_header_string with the os release where the data was collected
96 (uname -r) 97 (uname -r)
97 98
98 HEADER_VERSION = 5, 99 HEADER_VERSION = 5,
99 100
100 A perf_header_string with the perf user tool v 101 A perf_header_string with the perf user tool version where the
101 data was collected. This is the same as the ve 102 data was collected. This is the same as the version of the source tree
102 the perf tool was built from. 103 the perf tool was built from.
103 104
104 HEADER_ARCH = 6, 105 HEADER_ARCH = 6,
105 106
106 A perf_header_string with the CPU architecture 107 A perf_header_string with the CPU architecture (uname -m)
107 108
108 HEADER_NRCPUS = 7, 109 HEADER_NRCPUS = 7,
109 110
110 A structure defining the number of CPUs. 111 A structure defining the number of CPUs.
111 112
112 struct nr_cpus { 113 struct nr_cpus {
113 uint32_t nr_cpus_available; /* CPUs not <<
114 uint32_t nr_cpus_online; 114 uint32_t nr_cpus_online;
>> 115 uint32_t nr_cpus_available; /* CPUs not yet onlined */
115 }; 116 };
116 117
117 HEADER_CPUDESC = 8, 118 HEADER_CPUDESC = 8,
118 119
119 A perf_header_string with description of the C 120 A perf_header_string with description of the CPU. On x86 this is the model name
120 in /proc/cpuinfo 121 in /proc/cpuinfo
121 122
122 HEADER_CPUID = 9, 123 HEADER_CPUID = 9,
123 124
124 A perf_header_string with the exact CPU type. 125 A perf_header_string with the exact CPU type. On x86 this is
125 vendor,family,model,stepping. For example: Gen 126 vendor,family,model,stepping. For example: GenuineIntel,6,69,1
126 127
127 HEADER_TOTAL_MEM = 10, 128 HEADER_TOTAL_MEM = 10,
128 129
129 An uint64_t with the total memory in kilobytes !! 130 An uint64_t with the total memory in bytes.
130 131
131 HEADER_CMDLINE = 11, 132 HEADER_CMDLINE = 11,
132 133
133 A perf_header_string_list with the perf arg-ve !! 134 A perf_header_string with the perf command line used to collect the data.
134 135
135 HEADER_EVENT_DESC = 12, 136 HEADER_EVENT_DESC = 12,
136 137
137 Another description of the perf_event_attrs, m 138 Another description of the perf_event_attrs, more detailed than header.attrs
138 including IDs and names. See perf_event.h or t 139 including IDs and names. See perf_event.h or the man page for a description
139 of a struct perf_event_attr. 140 of a struct perf_event_attr.
140 141
141 struct { 142 struct {
142 uint32_t nr; /* number of events */ 143 uint32_t nr; /* number of events */
143 uint32_t attr_size; /* size of each per 144 uint32_t attr_size; /* size of each perf_event_attr */
144 struct { 145 struct {
145 struct perf_event_attr attr; /* 146 struct perf_event_attr attr; /* size of attr_size */
146 uint32_t nr_ids; 147 uint32_t nr_ids;
147 struct perf_header_string event_ 148 struct perf_header_string event_string;
148 uint64_t ids[nr_ids]; 149 uint64_t ids[nr_ids];
149 } events[nr]; /* Variable length record 150 } events[nr]; /* Variable length records */
150 }; 151 };
151 152
152 HEADER_CPU_TOPOLOGY = 13, 153 HEADER_CPU_TOPOLOGY = 13,
153 154
154 struct { !! 155 String lists defining the core and CPU threads topology.
155 /* <<
156 * First revision of HEADER_CPU_TOPOLO <<
157 * <<
158 * See 'struct perf_header_string_list <<
159 * in this file. <<
160 */ <<
161 156
>> 157 struct {
162 struct perf_header_string_list cores; / 158 struct perf_header_string_list cores; /* Variable length */
163 struct perf_header_string_list threads; 159 struct perf_header_string_list threads; /* Variable length */
164 <<
165 /* <<
166 * Second revision of HEADER_CPU_TOPOLO <<
167 * will not consider what comes next <<
168 */ <<
169 <<
170 struct { <<
171 uint32_t core_id; <<
172 uint32_t socket_id; <<
173 } cpus[nr]; /* Variable length records <<
174 /* 'nr' comes from previously processed <<
175 <<
176 /* <<
177 * Third revision of HEADER_CPU_TOPOLO <<
178 * will not consider what comes next <<
179 */ <<
180 <<
181 struct perf_header_string_list dies; / <<
182 uint32_t die_id[nr_cpus_avail]; /* fro <<
183 }; 160 };
184 161
185 Example: 162 Example:
186 sibling sockets : 0-8 !! 163 sibling cores : 0-3
187 sibling dies : 0-3 <<
188 sibling dies : 4-7 <<
189 sibling threads : 0-1 164 sibling threads : 0-1
190 sibling threads : 2-3 165 sibling threads : 2-3
191 sibling threads : 4-5 <<
192 sibling threads : 6-7 <<
193 166
194 HEADER_NUMA_TOPOLOGY = 14, 167 HEADER_NUMA_TOPOLOGY = 14,
195 168
196 A list of NUMA node descriptions 169 A list of NUMA node descriptions
197 170
198 struct { 171 struct {
199 uint32_t nr; 172 uint32_t nr;
200 struct { 173 struct {
201 uint32_t nodenr; 174 uint32_t nodenr;
202 uint64_t mem_total; 175 uint64_t mem_total;
203 uint64_t mem_free; 176 uint64_t mem_free;
204 struct perf_header_string cpus; 177 struct perf_header_string cpus;
205 } nodes[nr]; /* Variable length records 178 } nodes[nr]; /* Variable length records */
206 }; 179 };
207 180
208 HEADER_BRANCH_STACK = 15, 181 HEADER_BRANCH_STACK = 15,
209 182
210 Not implemented in perf. 183 Not implemented in perf.
211 184
212 HEADER_PMU_MAPPINGS = 16, 185 HEADER_PMU_MAPPINGS = 16,
213 186
214 A list of PMU structures, defining the 187 A list of PMU structures, defining the different PMUs supported by perf.
215 188
216 struct { 189 struct {
217 uint32_t nr; 190 uint32_t nr;
218 struct pmu { 191 struct pmu {
219 uint32_t pmu_type; 192 uint32_t pmu_type;
220 struct perf_header_string pmu_na 193 struct perf_header_string pmu_name;
221 } [nr]; /* Variable length records */ 194 } [nr]; /* Variable length records */
222 }; 195 };
223 196
224 HEADER_GROUP_DESC = 17, 197 HEADER_GROUP_DESC = 17,
225 198
226 Description of counter groups ({...} i 199 Description of counter groups ({...} in perf syntax)
227 200
228 struct { 201 struct {
229 uint32_t nr; 202 uint32_t nr;
230 struct { 203 struct {
231 struct perf_header_string stri 204 struct perf_header_string string;
232 uint32_t leader_idx; 205 uint32_t leader_idx;
233 uint32_t nr_members; 206 uint32_t nr_members;
234 } [nr]; /* Variable length records */ 207 } [nr]; /* Variable length records */
235 }; 208 };
236 209
237 HEADER_AUXTRACE = 18, 210 HEADER_AUXTRACE = 18,
238 211
239 Define additional auxtrace areas in the perf.d 212 Define additional auxtrace areas in the perf.data. auxtrace is used to store
240 undecoded hardware tracing information, such a 213 undecoded hardware tracing information, such as Intel Processor Trace data.
241 214
242 /** 215 /**
243 * struct auxtrace_index_entry - indexes a AUX 216 * struct auxtrace_index_entry - indexes a AUX area tracing event within a
244 * perf.data fil 217 * perf.data file.
245 * @file_offset: offset within the perf.data f 218 * @file_offset: offset within the perf.data file
246 * @sz: size of the event 219 * @sz: size of the event
247 */ 220 */
248 struct auxtrace_index_entry { 221 struct auxtrace_index_entry {
249 u64 file_offset; 222 u64 file_offset;
250 u64 sz; 223 u64 sz;
251 }; 224 };
252 225
253 #define PERF_AUXTRACE_INDEX_ENTRY_COUNT 256 226 #define PERF_AUXTRACE_INDEX_ENTRY_COUNT 256
254 227
255 /** 228 /**
256 * struct auxtrace_index - index of AUX area t 229 * struct auxtrace_index - index of AUX area tracing events within a perf.data
257 * file. 230 * file.
258 * @list: linking a number of arrays of entrie 231 * @list: linking a number of arrays of entries
259 * @nr: number of entries 232 * @nr: number of entries
260 * @entries: array of entries 233 * @entries: array of entries
261 */ 234 */
262 struct auxtrace_index { 235 struct auxtrace_index {
263 struct list_head list; 236 struct list_head list;
264 size_t nr; 237 size_t nr;
265 struct auxtrace_index_entry entries[PE 238 struct auxtrace_index_entry entries[PERF_AUXTRACE_INDEX_ENTRY_COUNT];
266 }; 239 };
267 240
268 HEADER_STAT = 19, <<
269 <<
270 This is merely a flag signifying that the data <<
271 recorded from perf stat record. <<
272 <<
273 HEADER_CACHE = 20, <<
274 <<
275 Description of the cache hierarchy. Based on t <<
276 in /sys/devices/system/cpu/cpu*/cache/ <<
277 <<
278 u32 version Currently always 1 <<
279 u32 number_of_cache_levels <<
280 <<
281 struct { <<
282 u32 level; <<
283 u32 line_size; <<
284 u32 sets; <<
285 u32 ways; <<
286 struct perf_header_string type; <<
287 struct perf_header_string size; <<
288 struct perf_header_string map; <<
289 }[number_of_cache_levels]; <<
290 <<
291 HEADER_SAMPLE_TIME = 21, <<
292 <<
293 Two uint64_t for the time of first sample and <<
294 <<
295 HEADER_SAMPLE_TOPOLOGY = 22, <<
296 <<
297 Physical memory map and its node assignments. <<
298 <<
299 The format of data in MEM_TOPOLOGY is as follo <<
300 <<
301 u64 version; // Currently 1 <<
302 u64 block_size_bytes; // /sys/device <<
303 u64 count; // number of n <<
304 <<
305 struct memory_node { <<
306 u64 node_id; // node index <<
307 u64 size; // size of bit <<
308 struct bitmap { <<
309 /* size of bitmap again */ <<
310 u64 bitmapsize; <<
311 /* bitmap of memory indexes th <<
312 /* /sys/devices/system/node/no <<
313 u64 entries[(bitmapsize/64)+1] <<
314 } <<
315 }[count]; <<
316 <<
317 The MEM_TOPOLOGY can be displayed with followi <<
318 <<
319 $ perf report --header-only -I <<
320 ... <<
321 # memory nodes (nr 1, block size 0x8000000): <<
322 # 0 [7G]: 0-23,32-69 <<
323 <<
324 HEADER_CLOCKID = 23, <<
325 <<
326 One uint64_t for the clockid frequency, specif <<
327 record -k' (see clock_gettime()), to enable ti <<
328 conversion into wall clock time on the reporti <<
329 <<
330 HEADER_DIR_FORMAT = 24, <<
331 <<
332 The data files layout is described by HEADER_D <<
333 holds only version number (1): <<
334 <<
335 uint64_t version; <<
336 <<
337 The current version holds only version value ( <<
338 <<
339 - Follow the 'data.*' name format. <<
340 <<
341 - Contain raw events data in standard perf for <<
342 to be sorted) <<
343 <<
344 Future versions are expected to describe diffe <<
345 to special needs. <<
346 <<
347 HEADER_BPF_PROG_INFO = 25, <<
348 <<
349 struct perf_bpil, which contains detailed info <<
350 a BPF program, including type, id, tag, jited/ <<
351 <<
352 HEADER_BPF_BTF = 26, <<
353 <<
354 Contains BPF Type Format (BTF). For more infor <<
355 refer to Documentation/bpf/btf.rst. <<
356 <<
357 struct { <<
358 u32 id; <<
359 u32 data_size; <<
360 char data[]; <<
361 }; <<
362 <<
363 HEADER_COMPRESSED = 27, <<
364 <<
365 struct { <<
366 u32 version; <<
367 u32 type; <<
368 u32 level; <<
369 u32 ratio; <<
370 u32 mmap_len; <<
371 }; <<
372 <<
373 Indicates that trace contains records of PERF_ <<
374 that have perf_events records in compressed fo <<
375 <<
376 HEADER_CPU_PMU_CAPS = 28, <<
377 <<
378 A list of cpu PMU capabilities. The fo <<
379 <<
380 struct { <<
381 u32 nr_cpu_pmu_caps; <<
382 { <<
383 char name[]; <<
384 char value[]; <<
385 } [nr_cpu_pmu_caps] <<
386 }; <<
387 <<
388 <<
389 Example: <<
390 cpu pmu capabilities: branches=32, max_precis <<
391 <<
392 HEADER_CLOCK_DATA = 29, <<
393 <<
394 Contains clock id and its reference ti <<
395 time taken at the 'same time', both va <<
396 The format of data is as below. <<
397 <<
398 struct { <<
399 u32 version; /* version = 1 */ <<
400 u32 clockid; <<
401 u64 wall_clock_ns; <<
402 u64 clockid_time_ns; <<
403 }; <<
404 <<
405 HEADER_HYBRID_TOPOLOGY = 30, <<
406 <<
407 Indicate the hybrid CPUs. The format of data i <<
408 <<
409 struct { <<
410 u32 nr; <<
411 struct { <<
412 char pmu_name[]; <<
413 char cpus[]; <<
414 } [nr]; /* Variable length records */ <<
415 }; <<
416 <<
417 Example: <<
418 hybrid cpu system: <<
419 cpu_core cpu list : 0-15 <<
420 cpu_atom cpu list : 16-23 <<
421 <<
422 HEADER_PMU_CAPS = 31, <<
423 <<
424 List of pmu capabilities (except cpu p <<
425 covered by HEADER_CPU_PMU_CAPS). Note <<
426 capabilities are also stored here. <<
427 <<
428 struct { <<
429 u32 nr_pmu; <<
430 struct { <<
431 u32 nr_caps; <<
432 { <<
433 char name[]; <<
434 char value[]; <<
435 } [nr_caps]; <<
436 char pmu_name[]; <<
437 } [nr_pmu]; <<
438 }; <<
439 <<
440 other bits are reserved and should ign 241 other bits are reserved and should ignored for now
441 HEADER_FEAT_BITS = 256, 242 HEADER_FEAT_BITS = 256,
442 243
443 Attributes 244 Attributes
444 245
445 This is an array of perf_event_attrs, each att 246 This is an array of perf_event_attrs, each attr_size bytes long, which defines
446 each event collected. See perf_event.h or the 247 each event collected. See perf_event.h or the man page for a detailed
447 description. 248 description.
448 249
449 Data 250 Data
450 251
451 This section is the bulk of the file. It consi 252 This section is the bulk of the file. It consist of a stream of perf_events
452 describing events. This matches the format gen 253 describing events. This matches the format generated by the kernel.
453 See perf_event.h or the manpage for a detailed 254 See perf_event.h or the manpage for a detailed description.
454 255
455 Some notes on parsing: 256 Some notes on parsing:
456 257
457 Ordering 258 Ordering
458 259
459 The events are not necessarily in time stamp o 260 The events are not necessarily in time stamp order, as they can be
460 collected in parallel on different CPUs. If th 261 collected in parallel on different CPUs. If the events should be
461 processed in time order they need to be sorted 262 processed in time order they need to be sorted first. It is possible
462 to only do a partial sort using the FINISHED_R 263 to only do a partial sort using the FINISHED_ROUND event header (see
463 below). perf record guarantees that there is n 264 below). perf record guarantees that there is no reordering over a
464 FINISHED_ROUND. 265 FINISHED_ROUND.
465 266
466 ID vs IDENTIFIER 267 ID vs IDENTIFIER
467 268
468 When the event stream contains multiple events 269 When the event stream contains multiple events each event is identified
469 by an ID. This can be either through the PERF_ 270 by an ID. This can be either through the PERF_SAMPLE_ID or the
470 PERF_SAMPLE_IDENTIFIER header. The PERF_SAMPLE 271 PERF_SAMPLE_IDENTIFIER header. The PERF_SAMPLE_IDENTIFIER header is
471 at a fixed offset from the event header, which 272 at a fixed offset from the event header, which allows reliable
472 parsing of the header. Relying on ID may be am 273 parsing of the header. Relying on ID may be ambiguous.
473 IDENTIFIER is only supported by newer Linux ke 274 IDENTIFIER is only supported by newer Linux kernels.
474 275
475 Perf record specific events: 276 Perf record specific events:
476 277
477 In addition to the kernel generated event type 278 In addition to the kernel generated event types perf record adds its
478 own event types (in addition it also synthesiz 279 own event types (in addition it also synthesizes some kernel events,
479 for example MMAP events) 280 for example MMAP events)
480 281
481 PERF_RECORD_USER_TYPE_START 282 PERF_RECORD_USER_TYPE_START = 64,
482 PERF_RECORD_HEADER_ATTR 283 PERF_RECORD_HEADER_ATTR = 64,
483 284
484 struct attr_event { 285 struct attr_event {
485 struct perf_event_header header; 286 struct perf_event_header header;
486 struct perf_event_attr attr; 287 struct perf_event_attr attr;
487 uint64_t id[]; 288 uint64_t id[];
488 }; 289 };
489 290
490 PERF_RECORD_HEADER_EVENT_TYPE 291 PERF_RECORD_HEADER_EVENT_TYPE = 65, /* deprecated */
491 292
492 #define MAX_EVENT_NAME 64 293 #define MAX_EVENT_NAME 64
493 294
494 struct perf_trace_event_type { 295 struct perf_trace_event_type {
495 uint64_t event_id; 296 uint64_t event_id;
496 char name[MAX_EVENT_NAME]; 297 char name[MAX_EVENT_NAME];
497 }; 298 };
498 299
499 struct event_type_event { 300 struct event_type_event {
500 struct perf_event_header header; 301 struct perf_event_header header;
501 struct perf_trace_event_type event_typ 302 struct perf_trace_event_type event_type;
502 }; 303 };
503 304
504 305
505 PERF_RECORD_HEADER_TRACING_DATA 306 PERF_RECORD_HEADER_TRACING_DATA = 66,
506 307
507 Describe me 308 Describe me
508 309
509 struct tracing_data_event { 310 struct tracing_data_event {
510 struct perf_event_header header; 311 struct perf_event_header header;
511 uint32_t size; 312 uint32_t size;
512 }; 313 };
513 314
514 PERF_RECORD_HEADER_BUILD_ID 315 PERF_RECORD_HEADER_BUILD_ID = 67,
515 316
516 Define a ELF build ID for a referenced executa 317 Define a ELF build ID for a referenced executable.
517 318
518 struct build_id_event; /* See above * 319 struct build_id_event; /* See above */
519 320
520 PERF_RECORD_FINISHED_ROUND 321 PERF_RECORD_FINISHED_ROUND = 68,
521 322
522 No event reordering over this header. No paylo 323 No event reordering over this header. No payload.
523 324
524 PERF_RECORD_ID_INDEX 325 PERF_RECORD_ID_INDEX = 69,
525 326
526 Map event ids to CPUs and TIDs. 327 Map event ids to CPUs and TIDs.
527 328
528 struct id_index_entry { 329 struct id_index_entry {
529 uint64_t id; 330 uint64_t id;
530 uint64_t idx; 331 uint64_t idx;
531 uint64_t cpu; 332 uint64_t cpu;
532 uint64_t tid; 333 uint64_t tid;
533 }; 334 };
534 335
535 struct id_index_event { 336 struct id_index_event {
536 struct perf_event_header header; 337 struct perf_event_header header;
537 uint64_t nr; 338 uint64_t nr;
538 struct id_index_entry entries[nr]; 339 struct id_index_entry entries[nr];
539 }; 340 };
540 341
541 PERF_RECORD_AUXTRACE_INFO 342 PERF_RECORD_AUXTRACE_INFO = 70,
542 343
543 Auxtrace type specific information. Describe m 344 Auxtrace type specific information. Describe me
544 345
545 struct auxtrace_info_event { 346 struct auxtrace_info_event {
546 struct perf_event_header header; 347 struct perf_event_header header;
547 uint32_t type; 348 uint32_t type;
548 uint32_t reserved__; /* For alignment 349 uint32_t reserved__; /* For alignment */
549 uint64_t priv[]; 350 uint64_t priv[];
550 }; 351 };
551 352
552 PERF_RECORD_AUXTRACE 353 PERF_RECORD_AUXTRACE = 71,
553 354
554 Defines auxtrace data. Followed by the actual 355 Defines auxtrace data. Followed by the actual data. The contents of
555 the auxtrace data is dependent on the event an 356 the auxtrace data is dependent on the event and the CPU. For example
556 for Intel Processor Trace it contains Processo 357 for Intel Processor Trace it contains Processor Trace data generated
557 by the CPU. 358 by the CPU.
558 359
559 struct auxtrace_event { 360 struct auxtrace_event {
560 struct perf_event_header header; 361 struct perf_event_header header;
561 uint64_t size; 362 uint64_t size;
562 uint64_t offset; 363 uint64_t offset;
563 uint64_t reference; 364 uint64_t reference;
564 uint32_t idx; 365 uint32_t idx;
565 uint32_t tid; 366 uint32_t tid;
566 uint32_t cpu; 367 uint32_t cpu;
567 uint32_t reserved__; /* For alignment 368 uint32_t reserved__; /* For alignment */
568 }; 369 };
569 370
570 struct aux_event { 371 struct aux_event {
571 struct perf_event_header header; 372 struct perf_event_header header;
572 uint64_t aux_offset; 373 uint64_t aux_offset;
573 uint64_t aux_size; 374 uint64_t aux_size;
574 uint64_t flags; 375 uint64_t flags;
575 }; 376 };
576 377
577 PERF_RECORD_AUXTRACE_ERROR 378 PERF_RECORD_AUXTRACE_ERROR = 72,
578 379
579 Describes an error in hardware tracing 380 Describes an error in hardware tracing
580 381
581 enum auxtrace_error_type { 382 enum auxtrace_error_type {
582 PERF_AUXTRACE_ERROR_ITRACE = 1, 383 PERF_AUXTRACE_ERROR_ITRACE = 1,
583 PERF_AUXTRACE_ERROR_MAX 384 PERF_AUXTRACE_ERROR_MAX
584 }; 385 };
585 386
586 #define MAX_AUXTRACE_ERROR_MSG 64 387 #define MAX_AUXTRACE_ERROR_MSG 64
587 388
588 struct auxtrace_error_event { 389 struct auxtrace_error_event {
589 struct perf_event_header header; 390 struct perf_event_header header;
590 uint32_t type; 391 uint32_t type;
591 uint32_t code; 392 uint32_t code;
592 uint32_t cpu; 393 uint32_t cpu;
593 uint32_t pid; 394 uint32_t pid;
594 uint32_t tid; 395 uint32_t tid;
595 uint32_t reserved__; /* For alignment 396 uint32_t reserved__; /* For alignment */
596 uint64_t ip; 397 uint64_t ip;
597 char msg[MAX_AUXTRACE_ERROR_MSG]; 398 char msg[MAX_AUXTRACE_ERROR_MSG];
598 }; 399 };
599 400
600 PERF_RECORD_HEADER_FEATURE <<
601 <<
602 Describes a header feature. These are records <<
603 contain information that otherwise would be in <<
604 <<
605 PERF_RECORD_COMPRESSED <<
606 <<
607 struct compressed_event { <<
608 struct perf_event_header header <<
609 char data[] <<
610 }; <<
611 <<
612 PERF_RECORD_FINISHED_INIT <<
613 <<
614 Marks the end of records for the system, pre-e <<
615 sessions, etc. Those are the ones prefixed PER <<
616 <<
617 This is used, for instance, to 'perf inject' e <<
618 regular events, those emitted by the kernel, t <<
619 host records. <<
620 <<
621 <<
622 The header is followed by compressed data fram <<
623 into array of perf trace records. The size of <<
624 record including the header is limited by the <<
625 <<
626 Event types 401 Event types
627 402
628 Define the event attributes with their IDs. 403 Define the event attributes with their IDs.
629 404
630 An array bound by the perf_file_section size. 405 An array bound by the perf_file_section size.
631 406
632 struct { 407 struct {
633 struct perf_event_attr attr; 408 struct perf_event_attr attr; /* Size defined by header.attr_size */
634 struct perf_file_section ids; 409 struct perf_file_section ids;
635 } 410 }
636 411
637 ids points to a array of uint64_t defining the 412 ids points to a array of uint64_t defining the ids for event attr attr.
638 413
639 Pipe-mode data 414 Pipe-mode data
640 415
641 Pipe-mode avoid seeks in the file by removing 416 Pipe-mode avoid seeks in the file by removing the perf_file_section and flags
642 from the struct perf_header. The trimmed heade 417 from the struct perf_header. The trimmed header is:
643 418
644 struct perf_pipe_file_header { 419 struct perf_pipe_file_header {
645 u64 magic; 420 u64 magic;
646 u64 size; 421 u64 size;
647 }; 422 };
648 423
649 The information about attrs, data, and event_t 424 The information about attrs, data, and event_types is instead in the
650 synthesized events PERF_RECORD_ATTR, PERF_RECO !! 425 synthesized events PERF_RECORD_ATTR, PERF_RECORD_HEADER_TRACING_DATA and
651 PERF_RECORD_HEADER_EVENT_TYPE, and PERF_RECORD !! 426 PERF_RECORD_HEADER_EVENT_TYPE that are generated by perf record in pipe-mode.
652 that are generated by perf record in pipe-mode <<
653 427
654 428
655 References: 429 References:
656 430
657 include/uapi/linux/perf_event.h 431 include/uapi/linux/perf_event.h
658 432
659 This is the canonical description of the kerne 433 This is the canonical description of the kernel generated perf_events
660 and the perf_event_attrs. 434 and the perf_event_attrs.
661 435
662 perf_events manpage 436 perf_events manpage
663 437
664 A manpage describing perf_event and perf_event 438 A manpage describing perf_event and perf_event_attr is here:
665 http://web.eece.maine.edu/~vweaver/projects/pe 439 http://web.eece.maine.edu/~vweaver/projects/perf_events/programming.html
666 This tends to be slightly behind the kernel in 440 This tends to be slightly behind the kernel include, but has better
667 descriptions. An (typically older) version of 441 descriptions. An (typically older) version of the man page may be
668 included with the standard Linux man pages, av 442 included with the standard Linux man pages, available with "man
669 perf_events" 443 perf_events"
670 444
671 pmu-tools 445 pmu-tools
672 446
673 https://github.com/andikleen/pmu-tools/tree/ma 447 https://github.com/andikleen/pmu-tools/tree/master/parser
674 448
675 A definition of the perf.data format in python 449 A definition of the perf.data format in python "construct" format is available
676 in pmu-tools parser. This allows to read perf. 450 in pmu-tools parser. This allows to read perf.data from python and dump it.
677 451
678 quipper 452 quipper
679 453
680 The quipper C++ parser is available at 454 The quipper C++ parser is available at
681 http://github.com/google/perf_data_converter/t !! 455 https://chromium.googlesource.com/chromiumos/platform2
>> 456
>> 457 It is under the chromiumos-wide-profiling/ subdirectory. This library can
>> 458 convert a perf data file to a protobuf and vice versa.
682 459
>> 460 Unfortunately this parser tends to be many versions behind and may not be able
>> 461 to parse data files generated by recent perf.
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