perf unwind: Fix map reference counts

The result of thread__find_map is the map in the passed in
addr_location. Calling addr_location__exit puts that map and so copies
need to do a map__get. Add in the corresponding map__puts.

v2. Add missing map__put when dso is missing.

Signed-off-by: Ian Rogers <[e-mail]>
Acked-by: Namhyung Kim <[e-mail]>
Cc: Mark Rutland <[e-mail]>
Cc: Ivan Babrou <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Adrian Hunter <[e-mail]>
Cc: Arnaldo Carvalho de Melo <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Namhyung Kim <[e-mail]>

tools/perf/util/unwind-libunwind-local.c

···
 	struct map *ret;
 
 	addr_location__init(&al);
-	ret = thread__find_map(ui->thread, PERF_RECORD_MISC_USER, ip, &al);
+	thread__find_map(ui->thread, PERF_RECORD_MISC_USER, ip, &al);
+	ret = map__get(al.map);
 	addr_location__exit(&al);
 	return ret;
 }
···
 		return -EINVAL;
 
 	dso = map__dso(map);
-	if (!dso)
+	if (!dso) {
+		map__put(map);
 		return -EINVAL;
+	}
 
 	pr_debug("unwind: find_proc_info dso %s\n", dso->name);
 
···
 
 		memset(&di, 0, sizeof(di));
 		if (dwarf_find_debug_frame(0, &di, ip, base, symfile, start, map__end(map)))
-			return dwarf_search_unwind_table(as, ip, &di, pi,
-							 need_unwind_info, arg);
+			ret = dwarf_search_unwind_table(as, ip, &di, pi,
+							need_unwind_info, arg);
 	}
 #endif
-
+	map__put(map);
 	return ret;
 }
 
···
 
 	dso = map__dso(map);
 
-	if (!dso)
+	if (!dso) {
+		map__put(map);
 		return -1;
+	}
 
 	size = dso__data_read_addr(dso, map, ui->machine,
 				   addr, (u8 *) data, sizeof(*data));
-
+	map__put(map);
 	return !(size == sizeof(*data));
 }