[PATCH 5/9] perf metric: Release expr_parse_ctx after testing

From: Namhyung Kim
Date: Sun Sep 06 2020 - 23:46:21 EST


The test_generic_metric() missed to release entries in the pctx.
Asan reported following leak (and more):

Direct leak of 128 byte(s) in 1 object(s) allocated from:
#0 0x7f4c9396980e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e)
#1 0x55f7e748cc14 in hashmap_grow (/home/namhyung/project/linux/tools/perf/perf+0x90cc14)
#2 0x55f7e748d497 in hashmap__insert (/home/namhyung/project/linux/tools/perf/perf+0x90d497)
#3 0x55f7e7341667 in hashmap__set /home/namhyung/project/linux/tools/perf/util/hashmap.h:111
#4 0x55f7e7341667 in expr__add_ref util/expr.c:120
#5 0x55f7e7292436 in prepare_metric util/stat-shadow.c:783
#6 0x55f7e729556d in test_generic_metric util/stat-shadow.c:858
#7 0x55f7e712390b in compute_single tests/parse-metric.c:128
#8 0x55f7e712390b in __compute_metric tests/parse-metric.c:180
#9 0x55f7e712446d in compute_metric tests/parse-metric.c:196
#10 0x55f7e712446d in test_dcache_l2 tests/parse-metric.c:295
#11 0x55f7e712446d in test__parse_metric tests/parse-metric.c:355
#12 0x55f7e70be09b in run_test tests/builtin-test.c:410
#13 0x55f7e70be09b in test_and_print tests/builtin-test.c:440
#14 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661
#15 0x55f7e70c101a in cmd_test tests/builtin-test.c:807
#16 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#17 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#18 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#19 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#20 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308

Fixes: 6d432c4c8aa56 ("perf tools: Add test_generic_metric function")
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/util/stat-shadow.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
index e1ba6c1b916a..a5f42c22c484 100644
--- a/tools/perf/util/stat-shadow.c
+++ b/tools/perf/util/stat-shadow.c
@@ -853,14 +853,16 @@ static void generic_metric(struct perf_stat_config *config,
double test_generic_metric(struct metric_expr *mexp, int cpu, struct runtime_stat *st)
{
struct expr_parse_ctx pctx;
- double ratio;
+ double ratio = 0.0;

if (prepare_metric(mexp->metric_events, mexp->metric_refs, &pctx, cpu, st) < 0)
- return 0.;
+ goto out;

if (expr__parse(&ratio, &pctx, mexp->metric_expr, 1))
- return 0.;
+ ratio = 0.0;

+out:
+ expr__ctx_clear(&pctx);
return ratio;
}

--
2.28.0.526.ge36021eeef-goog