[PATCH v1 1/1] perf unwind: Fix map reference counts

From: Ian Rogers
Date: Thu Jun 22 2023 - 01:11:10 EST


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.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/util/unwind-libunwind-local.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/unwind-libunwind-local.c b/tools/perf/util/unwind-libunwind-local.c
index 36bf5100bad2..9cb82d7c7dc7 100644
--- a/tools/perf/util/unwind-libunwind-local.c
+++ b/tools/perf/util/unwind-libunwind-local.c
@@ -419,7 +419,8 @@ static struct map *find_map(unw_word_t ip, struct unwind_info *ui)
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;
}
@@ -476,11 +477,11 @@ find_proc_info(unw_addr_space_t as, unw_word_t ip, unw_proc_info_t *pi,

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;
}

@@ -539,7 +540,7 @@ static int access_dso_mem(struct unwind_info *ui, unw_word_t addr,

size = dso__data_read_addr(dso, map, ui->machine,
addr, (u8 *) data, sizeof(*data));
-
+ map__put(map);
return !(size == sizeof(*data));
}

--
2.41.0.162.gfafddb0af9-goog