perf thread_map: Add thread_map user level event

Adding the thread_map event to pass/store thread maps as data in
the pipe/perf.data.

Storing the thread ID along with the standard comm[16] thread name string.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Kan Liang <kan.liang@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1445784728-21732-4-git-send-email-jolsa@kernel.org
[ Renamed thread_map_data_event to thread_map_event_entry ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/event.c

@@ -37,6 +37,7 @@ static const char *perf_event__names[] = {
 	[PERF_RECORD_AUXTRACE_INFO]		= "AUXTRACE_INFO",
 	[PERF_RECORD_AUXTRACE]			= "AUXTRACE",
 	[PERF_RECORD_AUXTRACE_ERROR]		= "AUXTRACE_ERROR",
+	[PERF_RECORD_THREAD_MAP]		= "THREAD_MAP",
 };
 
 const char *perf_event__name(unsigned int id)

tools/perf/util/event.h

@@ -226,6 +226,7 @@ enum perf_user_event_type { /* above any possible kernel type */
 	PERF_RECORD_AUXTRACE_INFO		= 70,
 	PERF_RECORD_AUXTRACE			= 71,
 	PERF_RECORD_AUXTRACE_ERROR		= 72,
+	PERF_RECORD_THREAD_MAP			= 73,
 	PERF_RECORD_HEADER_MAX
 };
 
@@ -356,6 +357,17 @@ struct context_switch_event {
 	u32 next_prev_tid;
 };
 
+struct thread_map_event_entry {
+	u64	pid;
+	char	comm[16];
+};
+
+struct thread_map_event {
+	struct perf_event_header	header;
+	u64				nr;
+	struct thread_map_event_entry	entries[];
+};
+
 union perf_event {
 	struct perf_event_header	header;
 	struct mmap_event		mmap;
@@ -378,6 +390,7 @@ union perf_event {
 	struct aux_event		aux;
 	struct itrace_start_event	itrace_start;
 	struct context_switch_event	context_switch;
+	struct thread_map_event		thread_map;
 };
 
 void perf_event__print_totals(void);

tools/perf/util/session.c

@@ -296,6 +296,16 @@ int process_event_auxtrace_error_stub(struct perf_tool *tool __maybe_unused,
 	return 0;
 }
 
+
+static
+int process_event_thread_map_stub(struct perf_tool *tool __maybe_unused,
+				  union perf_event *event __maybe_unused,
+				  struct perf_session *session __maybe_unused)
+{
+	dump_printf(": unhandled!\n");
+	return 0;
+}
+
 void perf_tool__fill_defaults(struct perf_tool *tool)
 {
 	if (tool->sample == NULL)
@@ -346,6 +356,8 @@ void perf_tool__fill_defaults(struct perf_tool *tool)
 		tool->auxtrace = process_event_auxtrace_stub;
 	if (tool->auxtrace_error == NULL)
 		tool->auxtrace_error = process_event_auxtrace_error_stub;
+	if (tool->thread_map == NULL)
+		tool->thread_map = process_event_thread_map_stub;
 }
 
 static void swap_sample_id_all(union perf_event *event, void *data)
@@ -616,6 +628,17 @@ static void perf_event__auxtrace_error_swap(union perf_event *event,
 	event->auxtrace_error.ip   = bswap_64(event->auxtrace_error.ip);
 }
 
+static void perf_event__thread_map_swap(union perf_event *event,
+					bool sample_id_all __maybe_unused)
+{
+	unsigned i;
+
+	event->thread_map.nr = bswap_64(event->thread_map.nr);
+
+	for (i = 0; i < event->thread_map.nr; i++)
+		event->thread_map.entries[i].pid = bswap_64(event->thread_map.entries[i].pid);
+}
+
 typedef void (*perf_event__swap_op)(union perf_event *event,
 				    bool sample_id_all);
 
@@ -643,6 +666,7 @@ static perf_event__swap_op perf_event__swap_ops[] = {
 	[PERF_RECORD_AUXTRACE_INFO]	  = perf_event__auxtrace_info_swap,
 	[PERF_RECORD_AUXTRACE]		  = perf_event__auxtrace_swap,
 	[PERF_RECORD_AUXTRACE_ERROR]	  = perf_event__auxtrace_error_swap,
+	[PERF_RECORD_THREAD_MAP]	  = perf_event__thread_map_swap,
 	[PERF_RECORD_HEADER_MAX]	  = NULL,
 };
 
@@ -1179,6 +1203,8 @@ static s64 perf_session__process_user_event(struct perf_session *session,
 	case PERF_RECORD_AUXTRACE_ERROR:
 		perf_session__auxtrace_error_inc(session, event);
 		return tool->auxtrace_error(tool, event, session);
+	case PERF_RECORD_THREAD_MAP:
+		return tool->thread_map(tool, event, session);
 	default:
 		return -EINVAL;
 	}

tools/perf/util/tool.h

@@ -55,7 +55,8 @@ struct perf_tool {
 	event_op2	build_id,
 			id_index,
 			auxtrace_info,
-			auxtrace_error;
+			auxtrace_error,
+			thread_map;
 	event_op3	auxtrace;
 	bool		ordered_events;
 	bool		ordering_requires_timestamps;