perf tools: Add support for PERF_RECORD_ITRACE_START

Add support for the PERF_RECORD_ITRACE_START event type.  This event can
be used to determine the pid and tid that are running when Instruction
Tracing starts.  Generally that information would come from a
sched_switch event but, at the start, no sched_switch events may yet
have been recorded.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1430404667-10593-8-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index b3c350e..7eecd5e 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -330,6 +330,11 @@
 	u64	flags;
 };
 
+struct itrace_start_event {
+	struct perf_event_header header;
+	u32 pid, tid;
+};
+
 union perf_event {
 	struct perf_event_header	header;
 	struct mmap_event		mmap;
@@ -349,6 +354,7 @@
 	struct auxtrace_event		auxtrace;
 	struct auxtrace_error_event	auxtrace_error;
 	struct aux_event		aux;
+	struct itrace_start_event	itrace_start;
 };
 
 void perf_event__print_totals(void);
@@ -388,6 +394,10 @@
 			    union perf_event *event,
 			    struct perf_sample *sample,
 			    struct machine *machine);
+int perf_event__process_itrace_start(struct perf_tool *tool,
+				     union perf_event *event,
+				     struct perf_sample *sample,
+				     struct machine *machine);
 int perf_event__process_mmap(struct perf_tool *tool,
 			     union perf_event *event,
 			     struct perf_sample *sample,
@@ -446,6 +456,7 @@
 size_t perf_event__fprintf_mmap2(union perf_event *event, FILE *fp);
 size_t perf_event__fprintf_task(union perf_event *event, FILE *fp);
 size_t perf_event__fprintf_aux(union perf_event *event, FILE *fp);
+size_t perf_event__fprintf_itrace_start(union perf_event *event, FILE *fp);
 size_t perf_event__fprintf(union perf_event *event, FILE *fp);
 
 u64 kallsyms__get_function_start(const char *kallsyms_filename,