perf unwind: Move unwind__prepare_access from thread_new into thread__insert_map

To determine the libunwind methods to use, we should get the
32bit/64bit information from maps of a thread. When a thread is newly
created, the information is not prepared. This patch moves
unwind__prepare_access() into thread__insert_map() so we can get the
information we need from maps. Meanwhile, let thread__insert_map()
return value and show messages on error.

Signed-off-by: He Kuang <[e-mail]>
Acked-by: Jiri Olsa <[e-mail]>
Cc: Adrian Hunter <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Andi Kleen <[e-mail]>
Cc: David Ahern <[e-mail]>
Cc: Ekaterina Tumanova <[e-mail]>
Cc: Josh Poimboeuf <[e-mail]>
Cc: Kan Liang <[e-mail]>
Cc: Masami Hiramatsu <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Pekka Enberg <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Stephane Eranian <[e-mail]>
Cc: Sukadev Bhattiprolu <[e-mail]>
Cc: Wang Nan <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/machine.c

···
 	if (map == NULL)
 		goto out_problem_map;
 
-	thread__insert_map(thread, map);
+	ret = thread__insert_map(thread, map);
+	if (ret)
+		goto out_problem_insert;
+
 	thread__put(thread);
 	map__put(map);
 	return 0;
 
+out_problem_insert:
+	map__put(map);
 out_problem_map:
 	thread__put(thread);
 out_problem:
···
 	if (map == NULL)
 		goto out_problem_map;
 
-	thread__insert_map(thread, map);
+	ret = thread__insert_map(thread, map);
+	if (ret)
+		goto out_problem_insert;
+
 	thread__put(thread);
 	map__put(map);
 	return 0;
 
+out_problem_insert:
+	map__put(map);
 out_problem_map:
 	thread__put(thread);
 out_problem:

tools/perf/util/thread.c

···
 		thread->cpu = -1;
 		INIT_LIST_HEAD(&thread->comm_list);
 
-		if (unwind__prepare_access(thread) < 0)
-			goto err_thread;
-
 		comm_str = malloc(32);
 		if (!comm_str)
 			goto err_thread;
···
 	       map_groups__fprintf(thread->mg, fp);
 }
 
-void thread__insert_map(struct thread *thread, struct map *map)
+int thread__insert_map(struct thread *thread, struct map *map)
 {
+	int ret;
+
+	ret = unwind__prepare_access(thread);
+	if (ret)
+		return ret;
+
 	map_groups__fixup_overlappings(thread->mg, map, stderr);
 	map_groups__insert(thread->mg, map);
+
+	return 0;
 }
 
 static int thread__clone_map_groups(struct thread *thread,

tools/perf/util/thread.h

···
 struct comm *thread__comm(const struct thread *thread);
 struct comm *thread__exec_comm(const struct thread *thread);
 const char *thread__comm_str(const struct thread *thread);
-void thread__insert_map(struct thread *thread, struct map *map);
+int thread__insert_map(struct thread *thread, struct map *map);
 int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp);
 size_t thread__fprintf(struct thread *thread, FILE *fp);