perf tools: Merge trace.info content into perf.data

This drops the trace.info file and move its contents into the
common perf.data file.

This is done by creating a new trace_info section into this file. A
user of perf headers needs to call perf_header__set_trace_info() to
save the trace meta informations into the perf.data file.

A file created by perf after his patch is unsupported by previous
version because the size of the headers have increased.

That said, it's two new fields that have been added in the end of
the headers, and those could be ignored by previous versions if
they just handled the dynamic header size and then ignore the
unknow part. The offsets guarantee the compatibility. We'll do a
-stable fix for that.

But current previous versions handle the header size using its
static size, not dynamic, then it's not backward compatible with
trace records.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091006213643.GA5343@nowhere>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 3 insertions, 1 deletions

diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
index a2916b652a1b..30aee5160dc0 100644
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -21,6 +21,8 @@ struct perf_header {
 	u64 data_size;
 	u64 event_offset;
 	u64 event_size;
+	u64 trace_info_offset;
+	u64 trace_info_size;
 };
 
 struct perf_header *perf_header__read(int fd);
@@ -40,7 +42,7 @@ void perf_header_attr__add_id(struct perf_header_attr *self, u64 id);
 u64 perf_header__sample_type(struct perf_header *header);
 struct perf_event_attr *
 perf_header__find_attr(u64 id, struct perf_header *header);
-
+void perf_header__set_trace_info(void);
 
 struct perf_header *perf_header__new(void);