[PATCH] perf hist: Fix memory leak of a perf_hpp_fmt

From: Ian Rogers
Date: Thu Nov 18 2021 - 02:13:29 EST


perf_hpp__column_unregister removes an entry from a list but doesn't
free the memory causing a memory leak spotted by leak sanitizer. Add the
free while at the same time reducing the scope of the function to
static.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/ui/hist.c | 28 ++++++++++++++--------------
tools/perf/util/hist.h | 1 -
2 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/tools/perf/ui/hist.c b/tools/perf/ui/hist.c
index c1f24d004852..5075ecead5f3 100644
--- a/tools/perf/ui/hist.c
+++ b/tools/perf/ui/hist.c
@@ -535,6 +535,18 @@ struct perf_hpp_list perf_hpp_list = {
#undef __HPP_SORT_ACC_FN
#undef __HPP_SORT_RAW_FN

+static void fmt_free(struct perf_hpp_fmt *fmt)
+{
+ /*
+ * At this point fmt should be completely
+ * unhooked, if not it's a bug.
+ */
+ BUG_ON(!list_empty(&fmt->list));
+ BUG_ON(!list_empty(&fmt->sort_list));
+
+ if (fmt->free)
+ fmt->free(fmt);
+}

void perf_hpp__init(void)
{
@@ -598,9 +610,10 @@ void perf_hpp_list__prepend_sort_field(struct perf_hpp_list *list,
list_add(&format->sort_list, &list->sorts);
}

-void perf_hpp__column_unregister(struct perf_hpp_fmt *format)
+static void perf_hpp__column_unregister(struct perf_hpp_fmt *format)
{
list_del_init(&format->list);
+ fmt_free(format);
}

void perf_hpp__cancel_cumulate(void)
@@ -672,19 +685,6 @@ void perf_hpp__append_sort_keys(struct perf_hpp_list *list)
}


-static void fmt_free(struct perf_hpp_fmt *fmt)
-{
- /*
- * At this point fmt should be completely
- * unhooked, if not it's a bug.
- */
- BUG_ON(!list_empty(&fmt->list));
- BUG_ON(!list_empty(&fmt->sort_list));
-
- if (fmt->free)
- fmt->free(fmt);
-}
-
void perf_hpp__reset_output_field(struct perf_hpp_list *list)
{
struct perf_hpp_fmt *fmt, *tmp;
diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index 5343b62476e6..621f35ae1efa 100644
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -369,7 +369,6 @@ enum {
};

void perf_hpp__init(void);
-void perf_hpp__column_unregister(struct perf_hpp_fmt *format);
void perf_hpp__cancel_cumulate(void);
void perf_hpp__setup_output_field(struct perf_hpp_list *list);
void perf_hpp__reset_output_field(struct perf_hpp_list *list);
--
2.34.0.rc1.387.gb447b232ab-goog