perf tools: Add stat config user level event

Adding the stat config event to pass/store stat config data, so report
tools (report/script) know how to interpret stat data.

The config data is stored in a 'tag|value' way to allow for easy
extension and backwards compatibility.
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/1445784728-21732-12-git-send-email-jolsa@kernel.org
[ stat_config_term_event -> stat_config_event_entry ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/event.c

@@ -39,6 +39,7 @@ static const char *perf_event__names[] = {
 	[PERF_RECORD_AUXTRACE_ERROR]		= "AUXTRACE_ERROR",
 	[PERF_RECORD_THREAD_MAP]		= "THREAD_MAP",
 	[PERF_RECORD_CPU_MAP]			= "CPU_MAP",
+	[PERF_RECORD_STAT_CONFIG]		= "STAT_CONFIG",
 };
 
 const char *perf_event__name(unsigned int id)

tools/perf/util/event.h

@@ -228,6 +228,7 @@ enum perf_user_event_type { /* above any possible kernel type */
 	PERF_RECORD_AUXTRACE_ERROR		= 72,
 	PERF_RECORD_THREAD_MAP			= 73,
 	PERF_RECORD_CPU_MAP			= 74,
+	PERF_RECORD_STAT_CONFIG			= 75,
 	PERF_RECORD_HEADER_MAX
 };
 
@@ -395,6 +396,24 @@ struct thread_map_event {
 	struct thread_map_event_entry	entries[];
 };
 
+enum {
+	PERF_STAT_CONFIG_TERM__AGGR_MODE	= 0,
+	PERF_STAT_CONFIG_TERM__INTERVAL		= 1,
+	PERF_STAT_CONFIG_TERM__SCALE		= 2,
+	PERF_STAT_CONFIG_TERM__MAX		= 3,
+};
+
+struct stat_config_event_entry {
+	u64	tag;
+	u64	val;
+};
+
+struct stat_config_event {
+	struct perf_event_header	header;
+	u64				nr;
+	struct stat_config_event_entry	data[];
+};
+
 union perf_event {
 	struct perf_event_header	header;
 	struct mmap_event		mmap;
@@ -419,6 +438,7 @@ union perf_event {
 	struct context_switch_event	context_switch;
 	struct thread_map_event		thread_map;
 	struct cpu_map_event		cpu_map;
+	struct stat_config_event	stat_config;
 };
 
 void perf_event__print_totals(void);

tools/perf/util/session.c

@@ -315,6 +315,15 @@ int process_event_cpu_map_stub(struct perf_tool *tool __maybe_unused,
 	return 0;
 }
 
+static
+int process_event_stat_config_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)
@@ -369,6 +378,8 @@ void perf_tool__fill_defaults(struct perf_tool *tool)
 		tool->thread_map = process_event_thread_map_stub;
 	if (tool->cpu_map == NULL)
 		tool->cpu_map = process_event_cpu_map_stub;
+	if (tool->stat_config == NULL)
+		tool->stat_config = process_event_stat_config_stub;
 }
 
 static void swap_sample_id_all(union perf_event *event, void *data)
@@ -686,6 +697,16 @@ static void perf_event__cpu_map_swap(union perf_event *event,
 	}
 }
 
+static void perf_event__stat_config_swap(union perf_event *event,
+					 bool sample_id_all __maybe_unused)
+{
+	u64 size;
+
+	size  = event->stat_config.nr * sizeof(event->stat_config.data[0]);
+	size += 1; /* nr item itself */
+	mem_bswap_64(&event->stat_config.nr, size);
+}
+
 typedef void (*perf_event__swap_op)(union perf_event *event,
 				    bool sample_id_all);
 
@@ -715,6 +736,7 @@ static perf_event__swap_op perf_event__swap_ops[] = {
 	[PERF_RECORD_AUXTRACE_ERROR]	  = perf_event__auxtrace_error_swap,
 	[PERF_RECORD_THREAD_MAP]	  = perf_event__thread_map_swap,
 	[PERF_RECORD_CPU_MAP]		  = perf_event__cpu_map_swap,
+	[PERF_RECORD_STAT_CONFIG]	  = perf_event__stat_config_swap,
 	[PERF_RECORD_HEADER_MAX]	  = NULL,
 };
 
@@ -1255,6 +1277,8 @@ static s64 perf_session__process_user_event(struct perf_session *session,
 		return tool->thread_map(tool, event, session);
 	case PERF_RECORD_CPU_MAP:
 		return tool->cpu_map(tool, event, session);
+	case PERF_RECORD_STAT_CONFIG:
+		return tool->stat_config(tool, event, session);
 	default:
 		return -EINVAL;
 	}

tools/perf/util/tool.h

@@ -57,7 +57,8 @@ struct perf_tool {
 			auxtrace_info,
 			auxtrace_error,
 			thread_map,
-			cpu_map;
+			cpu_map,
+			stat_config;
 	event_op3	auxtrace;
 	bool		ordered_events;
 	bool		ordering_requires_timestamps;