perf: Convert perf header build_ids into build_id events

Bypasses the build_id perf header code and replaces it with a
synthesized event and processing function that accomplishes the
same thing, used when reading/writing perf data to/from a pipe.

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: fweisbec@gmail.com
Cc: rostedt@goodmis.org
Cc: k-keiichi@bx.jp.nec.com
Cc: acme@ghostprotocols.net
LKML-Reference: <1270184365-8281-9-git-send-email-tzanussi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 3775abe..0bde31bc 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -426,10 +426,19 @@
 
 static void atexit_header(void)
 {
-	session->header.data_size += bytes_written;
+	if (!pipe_output) {
+		session->header.data_size += bytes_written;
 
-	process_buildids();
-	perf_header__write(&session->header, output, true);
+		process_buildids();
+		perf_header__write(&session->header, output, true);
+	} else {
+		int err;
+
+		err = event__synthesize_build_ids(process_synthesized_event,
+						  session);
+		if (err < 0)
+			pr_err("Couldn't synthesize build ids.\n");
+	}
 }
 
 static int __cmd_record(int argc, const char **argv)