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authorAlexey Budankov <alexey.budankov@linux.intel.com>2019-03-18 20:41:33 +0300
committerArnaldo Carvalho de Melo <acme@redhat.com>2019-05-15 22:36:49 +0300
commit42e1fd80a5b8bf9188ddb502b788433ece189aae (patch)
tree31791a14903175893fd217ca6c55c4d4a6da6b73 /tools/perf/Documentation
parentd3c8c08e75c4cbb6a940323092b40fcfd1de5380 (diff)
downloadlinux-42e1fd80a5b8bf9188ddb502b788433ece189aae.tar.xz
perf record: Implement COMPRESSED event record and its attributes
Implemented PERF_RECORD_COMPRESSED event, related data types, header feature and functions to write, read and print feature attributes from the trace header section. comp_mmap_len preserves the size of mmaped kernel buffer that was used during collection. comp_mmap_len size is used on loading stage as the size of decomp buffer for decompression of COMPRESSED events content. Committer notes: Fixed up conflict with BPF_PROG_INFO and BTF_BTF header features. Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/ebbaf031-8dda-3864-ebc6-7922d43ee515@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/Documentation')
-rw-r--r--tools/perf/Documentation/perf.data-file-format.txt24
1 files changed, 24 insertions, 0 deletions
diff --git a/tools/perf/Documentation/perf.data-file-format.txt b/tools/perf/Documentation/perf.data-file-format.txt
index 593ef49b273c..6967e9b02be5 100644
--- a/tools/perf/Documentation/perf.data-file-format.txt
+++ b/tools/perf/Documentation/perf.data-file-format.txt
@@ -272,6 +272,19 @@ struct {
Two uint64_t for the time of first sample and the time of last sample.
+ HEADER_COMPRESSED = 27,
+
+struct {
+ u32 version;
+ u32 type;
+ u32 level;
+ u32 ratio;
+ u32 mmap_len;
+};
+
+Indicates that trace contains records of PERF_RECORD_COMPRESSED type
+that have perf_events records in compressed form.
+
other bits are reserved and should ignored for now
HEADER_FEAT_BITS = 256,
@@ -437,6 +450,17 @@ 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,
+
+struct compressed_event {
+ struct perf_event_header header;
+ char data[];
+};
+
+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.
+
Event types
Define the event attributes with their IDs.