diff options
Diffstat (limited to 'tools/perf/Documentation/perf.data-file-format.txt')
-rw-r--r-- | tools/perf/Documentation/perf.data-file-format.txt | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/tools/perf/Documentation/perf.data-file-format.txt b/tools/perf/Documentation/perf.data-file-format.txt index 010a4edcd384..cd95ba09f727 100644 --- a/tools/perf/Documentation/perf.data-file-format.txt +++ b/tools/perf/Documentation/perf.data-file-format.txt @@ -370,7 +370,7 @@ struct { u32 mmap_len; }; -Indicates that trace contains records of PERF_RECORD_COMPRESSED type +Indicates that trace contains records of PERF_RECORD_COMPRESSED2 type that have perf_events records in compressed form. HEADER_CPU_PMU_CAPS = 28, @@ -602,7 +602,14 @@ struct auxtrace_error_event { Describes a header feature. These are records used in pipe-mode that contain information that otherwise would be in perf.data file's header. - PERF_RECORD_COMPRESSED = 81, + PERF_RECORD_COMPRESSED = 81, /* deprecated */ + +The header is followed by compressed data frame that can be decompressed +into array of perf trace records. The size of the entire compressed event +record including the header is limited by the max value of header.size. + +It is deprecated and new files should use PERF_RECORD_COMPRESSED2 to gurantee +8-byte alignment. struct compressed_event { struct perf_event_header header; @@ -618,10 +625,17 @@ This is used, for instance, to 'perf inject' events after init and before regular events, those emitted by the kernel, to support combining guest and host records. + PERF_RECORD_COMPRESSED2 = 83, -The header is followed by compressed data frame that can be decompressed -into array of perf trace records. The size of the entire compressed event -record including the header is limited by the max value of header.size. +8-byte aligned version of `PERF_RECORD_COMPRESSED`. `header.size` indicates the +total record size, including padding for 8-byte alignment, and `data_size` +specifies the actual size of the compressed data. + +struct perf_record_compressed2 { + struct perf_event_header header; + __u64 data_size; + char data[]; +}; Event types |