1d4897e19SAndi Kleenperf.data format 2d4897e19SAndi Kleen 3d4897e19SAndi KleenUptodate as of v4.7 4d4897e19SAndi Kleen 5d4897e19SAndi KleenThis document describes the on-disk perf.data format, generated by perf record 6d4897e19SAndi Kleenor perf inject and consumed by the other perf tools. 7d4897e19SAndi Kleen 8d4897e19SAndi KleenOn a high level perf.data contains the events generated by the PMUs, plus metadata. 9d4897e19SAndi Kleen 10d4897e19SAndi KleenAll fields are in native-endian of the machine that generated the perf.data. 11d4897e19SAndi Kleen 12d4897e19SAndi KleenWhen perf is writing to a pipe it uses a special version of the file 13d4897e19SAndi Kleenformat that does not rely on seeking to adjust data offsets. This 146d13491eSDavid Carrillo-Cisnerosformat is described in "Pipe-mode data" section. The pipe data version can be 156d13491eSDavid Carrillo-Cisnerosaugmented with additional events using perf inject. 16d4897e19SAndi Kleen 17d4897e19SAndi KleenThe file starts with a perf_header: 18d4897e19SAndi Kleen 19d4897e19SAndi Kleenstruct perf_header { 20d4897e19SAndi Kleen char magic[8]; /* PERFILE2 */ 21d4897e19SAndi Kleen uint64_t size; /* size of the header */ 22d4897e19SAndi Kleen uint64_t attr_size; /* size of an attribute in attrs */ 23d4897e19SAndi Kleen struct perf_file_section attrs; 24d4897e19SAndi Kleen struct perf_file_section data; 25d4897e19SAndi Kleen struct perf_file_section event_types; 26d4897e19SAndi Kleen uint64_t flags; 27d4897e19SAndi Kleen uint64_t flags1[3]; 28d4897e19SAndi Kleen}; 29d4897e19SAndi Kleen 30d4897e19SAndi KleenThe magic number identifies the perf file and the version. Current perf versions 31d4897e19SAndi Kleenuse PERFILE2. Old perf versions generated a version 1 format (PERFFILE). Version 1 32d4897e19SAndi Kleenis not described here. The magic number also identifies the endian. When the 33d4897e19SAndi Kleenmagic value is 64bit byte swapped compared the file is in non-native 34d4897e19SAndi Kleenendian. 35d4897e19SAndi Kleen 36d4897e19SAndi KleenA perf_file_section contains a pointer to another section of the perf file. 37d4897e19SAndi KleenThe header contains three such pointers: for attributes, data and event types. 38d4897e19SAndi Kleen 39d4897e19SAndi Kleenstruct perf_file_section { 40d4897e19SAndi Kleen uint64_t offset; /* offset from start of file */ 41d4897e19SAndi Kleen uint64_t size; /* size of the section */ 42d4897e19SAndi Kleen}; 43d4897e19SAndi Kleen 44d4897e19SAndi KleenFlags section: 45d4897e19SAndi Kleen 468c23a522SJonas RabensteinFor each of the optional features a perf_file_section it placed after the data 478c23a522SJonas Rabensteinsection if the feature bit is set in the perf_header flags bitset. The 488c23a522SJonas Rabensteinrespective perf_file_section points to the data of the additional header and 498c23a522SJonas Rabensteindefines its size. 50d4897e19SAndi Kleen 51d4897e19SAndi KleenSome headers consist of strings, which are defined like this: 52d4897e19SAndi Kleen 53d4897e19SAndi Kleenstruct perf_header_string { 54d4897e19SAndi Kleen uint32_t len; 55d4897e19SAndi Kleen char string[len]; /* zero terminated */ 56d4897e19SAndi Kleen}; 57d4897e19SAndi Kleen 58d4897e19SAndi KleenSome headers consist of a sequence of strings, which start with a 59d4897e19SAndi Kleen 60d4897e19SAndi Kleenstruct perf_header_string_list { 61d4897e19SAndi Kleen uint32_t nr; 62d4897e19SAndi Kleen struct perf_header_string strings[nr]; /* variable length records */ 63d4897e19SAndi Kleen}; 64d4897e19SAndi Kleen 65d4897e19SAndi KleenThe bits are the flags bits in a 256 bit bitmap starting with 66d4897e19SAndi Kleenflags. These define the valid bits: 67d4897e19SAndi Kleen 68d4897e19SAndi Kleen HEADER_RESERVED = 0, /* always cleared */ 69d4897e19SAndi Kleen HEADER_FIRST_FEATURE = 1, 70d4897e19SAndi Kleen HEADER_TRACING_DATA = 1, 71d4897e19SAndi Kleen 72d4897e19SAndi KleenDescribe me. 73d4897e19SAndi Kleen 74d4897e19SAndi Kleen HEADER_BUILD_ID = 2, 75d4897e19SAndi Kleen 76d4897e19SAndi KleenThe header consists of an sequence of build_id_event. The size of each record 77d4897e19SAndi Kleenis defined by header.size (see perf_event.h). Each event defines a ELF build id 78d4897e19SAndi Kleenfor a executable file name for a pid. An ELF build id is a unique identifier 79d4897e19SAndi Kleenassigned by the linker to an executable. 80d4897e19SAndi Kleen 81d4897e19SAndi Kleenstruct build_id_event { 82d4897e19SAndi Kleen struct perf_event_header header; 83d4897e19SAndi Kleen pid_t pid; 84d4897e19SAndi Kleen uint8_t build_id[24]; 85d4897e19SAndi Kleen char filename[header.size - offsetof(struct build_id_event, filename)]; 86d4897e19SAndi Kleen}; 87d4897e19SAndi Kleen 88d4897e19SAndi Kleen HEADER_HOSTNAME = 3, 89d4897e19SAndi Kleen 90d4897e19SAndi KleenA perf_header_string with the hostname where the data was collected 91d4897e19SAndi Kleen(uname -n) 92d4897e19SAndi Kleen 93d4897e19SAndi Kleen HEADER_OSRELEASE = 4, 94d4897e19SAndi Kleen 95d4897e19SAndi KleenA perf_header_string with the os release where the data was collected 96d4897e19SAndi Kleen(uname -r) 97d4897e19SAndi Kleen 98d4897e19SAndi Kleen HEADER_VERSION = 5, 99d4897e19SAndi Kleen 100d4897e19SAndi KleenA perf_header_string with the perf user tool version where the 101d4897e19SAndi Kleendata was collected. This is the same as the version of the source tree 102d4897e19SAndi Kleenthe perf tool was built from. 103d4897e19SAndi Kleen 104d4897e19SAndi Kleen HEADER_ARCH = 6, 105d4897e19SAndi Kleen 106d4897e19SAndi KleenA perf_header_string with the CPU architecture (uname -m) 107d4897e19SAndi Kleen 108d4897e19SAndi Kleen HEADER_NRCPUS = 7, 109d4897e19SAndi Kleen 110d4897e19SAndi KleenA structure defining the number of CPUs. 111d4897e19SAndi Kleen 112d4897e19SAndi Kleenstruct nr_cpus { 113d4897e19SAndi Kleen uint32_t nr_cpus_available; /* CPUs not yet onlined */ 11418a70574SArnaldo Carvalho de Melo uint32_t nr_cpus_online; 115d4897e19SAndi Kleen}; 116d4897e19SAndi Kleen 117d4897e19SAndi Kleen HEADER_CPUDESC = 8, 118d4897e19SAndi Kleen 119d4897e19SAndi KleenA perf_header_string with description of the CPU. On x86 this is the model name 120d4897e19SAndi Kleenin /proc/cpuinfo 121d4897e19SAndi Kleen 122d4897e19SAndi Kleen HEADER_CPUID = 9, 123d4897e19SAndi Kleen 124d4897e19SAndi KleenA perf_header_string with the exact CPU type. On x86 this is 125d4897e19SAndi Kleenvendor,family,model,stepping. For example: GenuineIntel,6,69,1 126d4897e19SAndi Kleen 127d4897e19SAndi Kleen HEADER_TOTAL_MEM = 10, 128d4897e19SAndi Kleen 129d4897e19SAndi KleenAn uint64_t with the total memory in bytes. 130d4897e19SAndi Kleen 131d4897e19SAndi Kleen HEADER_CMDLINE = 11, 132d4897e19SAndi Kleen 1337a663c0fSJonas RabensteinA perf_header_string_list with the perf arg-vector used to collect the data. 134d4897e19SAndi Kleen 135d4897e19SAndi Kleen HEADER_EVENT_DESC = 12, 136d4897e19SAndi Kleen 137d4897e19SAndi KleenAnother description of the perf_event_attrs, more detailed than header.attrs 138d4897e19SAndi Kleenincluding IDs and names. See perf_event.h or the man page for a description 139d4897e19SAndi Kleenof a struct perf_event_attr. 140d4897e19SAndi Kleen 141d4897e19SAndi Kleenstruct { 142d4897e19SAndi Kleen uint32_t nr; /* number of events */ 143d4897e19SAndi Kleen uint32_t attr_size; /* size of each perf_event_attr */ 144d4897e19SAndi Kleen struct { 145d4897e19SAndi Kleen struct perf_event_attr attr; /* size of attr_size */ 146d4897e19SAndi Kleen uint32_t nr_ids; 147d4897e19SAndi Kleen struct perf_header_string event_string; 148d4897e19SAndi Kleen uint64_t ids[nr_ids]; 149d4897e19SAndi Kleen } events[nr]; /* Variable length records */ 150d4897e19SAndi Kleen}; 151d4897e19SAndi Kleen 152d4897e19SAndi Kleen HEADER_CPU_TOPOLOGY = 13, 153d4897e19SAndi Kleen 154d4897e19SAndi KleenString lists defining the core and CPU threads topology. 1550c711138SThomas RichterThe string lists are followed by a variable length array 1560c711138SThomas Richterwhich contains core_id and socket_id of each cpu. 1570c711138SThomas RichterThe number of entries can be determined by the size of the 1580c711138SThomas Richtersection minus the sizes of both string lists. 159d4897e19SAndi Kleen 160d4897e19SAndi Kleenstruct { 161d4897e19SAndi Kleen struct perf_header_string_list cores; /* Variable length */ 162d4897e19SAndi Kleen struct perf_header_string_list threads; /* Variable length */ 1630c711138SThomas Richter struct { 1640c711138SThomas Richter uint32_t core_id; 1650c711138SThomas Richter uint32_t socket_id; 1660c711138SThomas Richter } cpus[nr]; /* Variable length records */ 167d4897e19SAndi Kleen}; 168d4897e19SAndi Kleen 169d4897e19SAndi KleenExample: 170d4897e19SAndi Kleen sibling cores : 0-3 171d4897e19SAndi Kleen sibling threads : 0-1 172d4897e19SAndi Kleen sibling threads : 2-3 173d4897e19SAndi Kleen 174d4897e19SAndi Kleen HEADER_NUMA_TOPOLOGY = 14, 175d4897e19SAndi Kleen 176d4897e19SAndi Kleen A list of NUMA node descriptions 177d4897e19SAndi Kleen 178d4897e19SAndi Kleenstruct { 179d4897e19SAndi Kleen uint32_t nr; 180d4897e19SAndi Kleen struct { 181d4897e19SAndi Kleen uint32_t nodenr; 182d4897e19SAndi Kleen uint64_t mem_total; 183d4897e19SAndi Kleen uint64_t mem_free; 184d4897e19SAndi Kleen struct perf_header_string cpus; 185d4897e19SAndi Kleen } nodes[nr]; /* Variable length records */ 186d4897e19SAndi Kleen}; 187d4897e19SAndi Kleen 188d4897e19SAndi Kleen HEADER_BRANCH_STACK = 15, 189d4897e19SAndi Kleen 190d4897e19SAndi KleenNot implemented in perf. 191d4897e19SAndi Kleen 192d4897e19SAndi Kleen HEADER_PMU_MAPPINGS = 16, 193d4897e19SAndi Kleen 194d4897e19SAndi Kleen A list of PMU structures, defining the different PMUs supported by perf. 195d4897e19SAndi Kleen 196d4897e19SAndi Kleenstruct { 197d4897e19SAndi Kleen uint32_t nr; 198d4897e19SAndi Kleen struct pmu { 199d4897e19SAndi Kleen uint32_t pmu_type; 200d4897e19SAndi Kleen struct perf_header_string pmu_name; 201d4897e19SAndi Kleen } [nr]; /* Variable length records */ 202d4897e19SAndi Kleen}; 203d4897e19SAndi Kleen 204d4897e19SAndi Kleen HEADER_GROUP_DESC = 17, 205d4897e19SAndi Kleen 206d4897e19SAndi Kleen Description of counter groups ({...} in perf syntax) 207d4897e19SAndi Kleen 208d4897e19SAndi Kleenstruct { 209d4897e19SAndi Kleen uint32_t nr; 210d4897e19SAndi Kleen struct { 211d4897e19SAndi Kleen struct perf_header_string string; 212d4897e19SAndi Kleen uint32_t leader_idx; 213d4897e19SAndi Kleen uint32_t nr_members; 214d4897e19SAndi Kleen } [nr]; /* Variable length records */ 215d4897e19SAndi Kleen}; 216d4897e19SAndi Kleen 217d4897e19SAndi Kleen HEADER_AUXTRACE = 18, 218d4897e19SAndi Kleen 219d4897e19SAndi KleenDefine additional auxtrace areas in the perf.data. auxtrace is used to store 220d4897e19SAndi Kleenundecoded hardware tracing information, such as Intel Processor Trace data. 221d4897e19SAndi Kleen 222d4897e19SAndi Kleen/** 223d4897e19SAndi Kleen * struct auxtrace_index_entry - indexes a AUX area tracing event within a 224d4897e19SAndi Kleen * perf.data file. 225d4897e19SAndi Kleen * @file_offset: offset within the perf.data file 226d4897e19SAndi Kleen * @sz: size of the event 227d4897e19SAndi Kleen */ 228d4897e19SAndi Kleenstruct auxtrace_index_entry { 229d4897e19SAndi Kleen u64 file_offset; 230d4897e19SAndi Kleen u64 sz; 231d4897e19SAndi Kleen}; 232d4897e19SAndi Kleen 233d4897e19SAndi Kleen#define PERF_AUXTRACE_INDEX_ENTRY_COUNT 256 234d4897e19SAndi Kleen 235d4897e19SAndi Kleen/** 236d4897e19SAndi Kleen * struct auxtrace_index - index of AUX area tracing events within a perf.data 237d4897e19SAndi Kleen * file. 238d4897e19SAndi Kleen * @list: linking a number of arrays of entries 239d4897e19SAndi Kleen * @nr: number of entries 240d4897e19SAndi Kleen * @entries: array of entries 241d4897e19SAndi Kleen */ 242d4897e19SAndi Kleenstruct auxtrace_index { 243d4897e19SAndi Kleen struct list_head list; 244d4897e19SAndi Kleen size_t nr; 245d4897e19SAndi Kleen struct auxtrace_index_entry entries[PERF_AUXTRACE_INDEX_ENTRY_COUNT]; 246d4897e19SAndi Kleen}; 247d4897e19SAndi Kleen 24835c0a81aSAndi Kleen HEADER_STAT = 19, 24935c0a81aSAndi Kleen 25035c0a81aSAndi KleenThis is merely a flag signifying that the data section contains data 25135c0a81aSAndi Kleenrecorded from perf stat record. 25235c0a81aSAndi Kleen 25335c0a81aSAndi Kleen HEADER_CACHE = 20, 25435c0a81aSAndi Kleen 25535c0a81aSAndi KleenDescription of the cache hierarchy. Based on the Linux sysfs format 25635c0a81aSAndi Kleenin /sys/devices/system/cpu/cpu*/cache/ 25735c0a81aSAndi Kleen 25835c0a81aSAndi Kleen u32 version Currently always 1 25935c0a81aSAndi Kleen u32 number_of_cache_levels 26035c0a81aSAndi Kleen 26135c0a81aSAndi Kleenstruct { 26235c0a81aSAndi Kleen u32 level; 26335c0a81aSAndi Kleen u32 line_size; 26435c0a81aSAndi Kleen u32 sets; 26535c0a81aSAndi Kleen u32 ways; 26635c0a81aSAndi Kleen struct perf_header_string type; 26735c0a81aSAndi Kleen struct perf_header_string size; 26835c0a81aSAndi Kleen struct perf_header_string map; 26935c0a81aSAndi Kleen}[number_of_cache_levels]; 27035c0a81aSAndi Kleen 2716011518dSJin Yao HEADER_SAMPLE_TIME = 21, 2726011518dSJin Yao 2736011518dSJin YaoTwo uint64_t for the time of first sample and the time of last sample. 2746011518dSJin Yao 275d4897e19SAndi Kleen other bits are reserved and should ignored for now 276d4897e19SAndi Kleen HEADER_FEAT_BITS = 256, 277d4897e19SAndi Kleen 278d4897e19SAndi KleenAttributes 279d4897e19SAndi Kleen 280d4897e19SAndi KleenThis is an array of perf_event_attrs, each attr_size bytes long, which defines 281d4897e19SAndi Kleeneach event collected. See perf_event.h or the man page for a detailed 282d4897e19SAndi Kleendescription. 283d4897e19SAndi Kleen 284d4897e19SAndi KleenData 285d4897e19SAndi Kleen 286d4897e19SAndi KleenThis section is the bulk of the file. It consist of a stream of perf_events 287d4897e19SAndi Kleendescribing events. This matches the format generated by the kernel. 288d4897e19SAndi KleenSee perf_event.h or the manpage for a detailed description. 289d4897e19SAndi Kleen 290d4897e19SAndi KleenSome notes on parsing: 291d4897e19SAndi Kleen 292d4897e19SAndi KleenOrdering 293d4897e19SAndi Kleen 294d4897e19SAndi KleenThe events are not necessarily in time stamp order, as they can be 295d4897e19SAndi Kleencollected in parallel on different CPUs. If the events should be 296d4897e19SAndi Kleenprocessed in time order they need to be sorted first. It is possible 297d4897e19SAndi Kleento only do a partial sort using the FINISHED_ROUND event header (see 298d4897e19SAndi Kleenbelow). perf record guarantees that there is no reordering over a 299d4897e19SAndi KleenFINISHED_ROUND. 300d4897e19SAndi Kleen 301d4897e19SAndi KleenID vs IDENTIFIER 302d4897e19SAndi Kleen 303d4897e19SAndi KleenWhen the event stream contains multiple events each event is identified 304d4897e19SAndi Kleenby an ID. This can be either through the PERF_SAMPLE_ID or the 305d4897e19SAndi KleenPERF_SAMPLE_IDENTIFIER header. The PERF_SAMPLE_IDENTIFIER header is 306d4897e19SAndi Kleenat a fixed offset from the event header, which allows reliable 3071291927aSKim Phillipsparsing of the header. Relying on ID may be ambiguous. 308d4897e19SAndi KleenIDENTIFIER is only supported by newer Linux kernels. 309d4897e19SAndi Kleen 310d4897e19SAndi KleenPerf record specific events: 311d4897e19SAndi Kleen 312d4897e19SAndi KleenIn addition to the kernel generated event types perf record adds its 313d4897e19SAndi Kleenown event types (in addition it also synthesizes some kernel events, 314d4897e19SAndi Kleenfor example MMAP events) 315d4897e19SAndi Kleen 316d4897e19SAndi Kleen PERF_RECORD_USER_TYPE_START = 64, 317d4897e19SAndi Kleen PERF_RECORD_HEADER_ATTR = 64, 318d4897e19SAndi Kleen 319d4897e19SAndi Kleenstruct attr_event { 320d4897e19SAndi Kleen struct perf_event_header header; 321d4897e19SAndi Kleen struct perf_event_attr attr; 322d4897e19SAndi Kleen uint64_t id[]; 323d4897e19SAndi Kleen}; 324d4897e19SAndi Kleen 3251291927aSKim Phillips PERF_RECORD_HEADER_EVENT_TYPE = 65, /* deprecated */ 326d4897e19SAndi Kleen 327d4897e19SAndi Kleen#define MAX_EVENT_NAME 64 328d4897e19SAndi Kleen 329d4897e19SAndi Kleenstruct perf_trace_event_type { 330d4897e19SAndi Kleen uint64_t event_id; 331d4897e19SAndi Kleen char name[MAX_EVENT_NAME]; 332d4897e19SAndi Kleen}; 333d4897e19SAndi Kleen 334d4897e19SAndi Kleenstruct event_type_event { 335d4897e19SAndi Kleen struct perf_event_header header; 336d4897e19SAndi Kleen struct perf_trace_event_type event_type; 337d4897e19SAndi Kleen}; 338d4897e19SAndi Kleen 339d4897e19SAndi Kleen 340d4897e19SAndi Kleen PERF_RECORD_HEADER_TRACING_DATA = 66, 341d4897e19SAndi Kleen 342d4897e19SAndi KleenDescribe me 343d4897e19SAndi Kleen 344d4897e19SAndi Kleenstruct tracing_data_event { 345d4897e19SAndi Kleen struct perf_event_header header; 346d4897e19SAndi Kleen uint32_t size; 347d4897e19SAndi Kleen}; 348d4897e19SAndi Kleen 349d4897e19SAndi Kleen PERF_RECORD_HEADER_BUILD_ID = 67, 350d4897e19SAndi Kleen 351d4897e19SAndi KleenDefine a ELF build ID for a referenced executable. 352d4897e19SAndi Kleen 353d4897e19SAndi Kleen struct build_id_event; /* See above */ 354d4897e19SAndi Kleen 355d4897e19SAndi Kleen PERF_RECORD_FINISHED_ROUND = 68, 356d4897e19SAndi Kleen 357d4897e19SAndi KleenNo event reordering over this header. No payload. 358d4897e19SAndi Kleen 359d4897e19SAndi Kleen PERF_RECORD_ID_INDEX = 69, 360d4897e19SAndi Kleen 361d4897e19SAndi KleenMap event ids to CPUs and TIDs. 362d4897e19SAndi Kleen 363d4897e19SAndi Kleenstruct id_index_entry { 364d4897e19SAndi Kleen uint64_t id; 365d4897e19SAndi Kleen uint64_t idx; 366d4897e19SAndi Kleen uint64_t cpu; 367d4897e19SAndi Kleen uint64_t tid; 368d4897e19SAndi Kleen}; 369d4897e19SAndi Kleen 370d4897e19SAndi Kleenstruct id_index_event { 371d4897e19SAndi Kleen struct perf_event_header header; 372d4897e19SAndi Kleen uint64_t nr; 373d4897e19SAndi Kleen struct id_index_entry entries[nr]; 374d4897e19SAndi Kleen}; 375d4897e19SAndi Kleen 376d4897e19SAndi Kleen PERF_RECORD_AUXTRACE_INFO = 70, 377d4897e19SAndi Kleen 378d4897e19SAndi KleenAuxtrace type specific information. Describe me 379d4897e19SAndi Kleen 380d4897e19SAndi Kleenstruct auxtrace_info_event { 381d4897e19SAndi Kleen struct perf_event_header header; 382d4897e19SAndi Kleen uint32_t type; 383d4897e19SAndi Kleen uint32_t reserved__; /* For alignment */ 384d4897e19SAndi Kleen uint64_t priv[]; 385d4897e19SAndi Kleen}; 386d4897e19SAndi Kleen 387d4897e19SAndi Kleen PERF_RECORD_AUXTRACE = 71, 388d4897e19SAndi Kleen 389d4897e19SAndi KleenDefines auxtrace data. Followed by the actual data. The contents of 390d4897e19SAndi Kleenthe auxtrace data is dependent on the event and the CPU. For example 391d4897e19SAndi Kleenfor Intel Processor Trace it contains Processor Trace data generated 392d4897e19SAndi Kleenby the CPU. 393d4897e19SAndi Kleen 394d4897e19SAndi Kleenstruct auxtrace_event { 395d4897e19SAndi Kleen struct perf_event_header header; 396d4897e19SAndi Kleen uint64_t size; 397d4897e19SAndi Kleen uint64_t offset; 398d4897e19SAndi Kleen uint64_t reference; 399d4897e19SAndi Kleen uint32_t idx; 400d4897e19SAndi Kleen uint32_t tid; 401d4897e19SAndi Kleen uint32_t cpu; 402d4897e19SAndi Kleen uint32_t reserved__; /* For alignment */ 403d4897e19SAndi Kleen}; 404d4897e19SAndi Kleen 405d4897e19SAndi Kleenstruct aux_event { 406d4897e19SAndi Kleen struct perf_event_header header; 407d4897e19SAndi Kleen uint64_t aux_offset; 408d4897e19SAndi Kleen uint64_t aux_size; 409d4897e19SAndi Kleen uint64_t flags; 410d4897e19SAndi Kleen}; 411d4897e19SAndi Kleen 412d4897e19SAndi Kleen PERF_RECORD_AUXTRACE_ERROR = 72, 413d4897e19SAndi Kleen 414d4897e19SAndi KleenDescribes an error in hardware tracing 415d4897e19SAndi Kleen 416d4897e19SAndi Kleenenum auxtrace_error_type { 417d4897e19SAndi Kleen PERF_AUXTRACE_ERROR_ITRACE = 1, 418d4897e19SAndi Kleen PERF_AUXTRACE_ERROR_MAX 419d4897e19SAndi Kleen}; 420d4897e19SAndi Kleen 421d4897e19SAndi Kleen#define MAX_AUXTRACE_ERROR_MSG 64 422d4897e19SAndi Kleen 423d4897e19SAndi Kleenstruct auxtrace_error_event { 424d4897e19SAndi Kleen struct perf_event_header header; 425d4897e19SAndi Kleen uint32_t type; 426d4897e19SAndi Kleen uint32_t code; 427d4897e19SAndi Kleen uint32_t cpu; 428d4897e19SAndi Kleen uint32_t pid; 429d4897e19SAndi Kleen uint32_t tid; 430d4897e19SAndi Kleen uint32_t reserved__; /* For alignment */ 431d4897e19SAndi Kleen uint64_t ip; 432d4897e19SAndi Kleen char msg[MAX_AUXTRACE_ERROR_MSG]; 433d4897e19SAndi Kleen}; 434d4897e19SAndi Kleen 435e9def1b2SDavid Carrillo-Cisneros PERF_RECORD_HEADER_FEATURE = 80, 436e9def1b2SDavid Carrillo-Cisneros 437e9def1b2SDavid Carrillo-CisnerosDescribes a header feature. These are records used in pipe-mode that 438e9def1b2SDavid Carrillo-Cisneroscontain information that otherwise would be in perf.data file's header. 439e9def1b2SDavid Carrillo-Cisneros 440d4897e19SAndi KleenEvent types 441d4897e19SAndi Kleen 442d4897e19SAndi KleenDefine the event attributes with their IDs. 443d4897e19SAndi Kleen 444d4897e19SAndi KleenAn array bound by the perf_file_section size. 445d4897e19SAndi Kleen 446d4897e19SAndi Kleen struct { 447d4897e19SAndi Kleen struct perf_event_attr attr; /* Size defined by header.attr_size */ 448d4897e19SAndi Kleen struct perf_file_section ids; 449d4897e19SAndi Kleen } 450d4897e19SAndi Kleen 451d4897e19SAndi Kleenids points to a array of uint64_t defining the ids for event attr attr. 452d4897e19SAndi Kleen 4536d13491eSDavid Carrillo-CisnerosPipe-mode data 4546d13491eSDavid Carrillo-Cisneros 4556d13491eSDavid Carrillo-CisnerosPipe-mode avoid seeks in the file by removing the perf_file_section and flags 4566d13491eSDavid Carrillo-Cisnerosfrom the struct perf_header. The trimmed header is: 4576d13491eSDavid Carrillo-Cisneros 4586d13491eSDavid Carrillo-Cisnerosstruct perf_pipe_file_header { 4596d13491eSDavid Carrillo-Cisneros u64 magic; 4606d13491eSDavid Carrillo-Cisneros u64 size; 4616d13491eSDavid Carrillo-Cisneros}; 4626d13491eSDavid Carrillo-Cisneros 4636d13491eSDavid Carrillo-CisnerosThe information about attrs, data, and event_types is instead in the 464e9def1b2SDavid Carrillo-Cisnerossynthesized events PERF_RECORD_ATTR, PERF_RECORD_HEADER_TRACING_DATA, 465e9def1b2SDavid Carrillo-CisnerosPERF_RECORD_HEADER_EVENT_TYPE, and PERF_RECORD_HEADER_FEATURE 466e9def1b2SDavid Carrillo-Cisnerosthat are generated by perf record in pipe-mode. 4676d13491eSDavid Carrillo-Cisneros 4686d13491eSDavid Carrillo-Cisneros 469d4897e19SAndi KleenReferences: 470d4897e19SAndi Kleen 471d4897e19SAndi Kleeninclude/uapi/linux/perf_event.h 472d4897e19SAndi Kleen 473d4897e19SAndi KleenThis is the canonical description of the kernel generated perf_events 474d4897e19SAndi Kleenand the perf_event_attrs. 475d4897e19SAndi Kleen 476d4897e19SAndi Kleenperf_events manpage 477d4897e19SAndi Kleen 478d4897e19SAndi KleenA manpage describing perf_event and perf_event_attr is here: 479d4897e19SAndi Kleenhttp://web.eece.maine.edu/~vweaver/projects/perf_events/programming.html 480d4897e19SAndi KleenThis tends to be slightly behind the kernel include, but has better 481d4897e19SAndi Kleendescriptions. An (typically older) version of the man page may be 482d4897e19SAndi Kleenincluded with the standard Linux man pages, available with "man 483d4897e19SAndi Kleenperf_events" 484d4897e19SAndi Kleen 485d4897e19SAndi Kleenpmu-tools 486d4897e19SAndi Kleen 487d4897e19SAndi Kleenhttps://github.com/andikleen/pmu-tools/tree/master/parser 488d4897e19SAndi Kleen 489d4897e19SAndi KleenA definition of the perf.data format in python "construct" format is available 490d4897e19SAndi Kleenin pmu-tools parser. This allows to read perf.data from python and dump it. 491d4897e19SAndi Kleen 492d4897e19SAndi Kleenquipper 493d4897e19SAndi Kleen 494d4897e19SAndi KleenThe quipper C++ parser is available at 4952427b432SStephane Eranianhttp://github.com/google/perf_data_converter/tree/master/src/quipper 4962acad195SSimon Que 497