Re: [PATCH v2] perf parse: Copy string to perf_evsel_config_term

From: Leo Yan
Date: Tue Jan 07 2020 - 05:09:21 EST


On Tue, Jan 07, 2020 at 10:16:09AM +0100, Jiri Olsa wrote:

[...]

> > diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
> > index ed7c008b9c8b..49b26504bee3 100644
> > --- a/tools/perf/util/parse-events.c
> > +++ b/tools/perf/util/parse-events.c
> > @@ -1220,7 +1220,6 @@ static int get_config_terms(struct list_head *head_config,
> > struct list_head *head_terms __maybe_unused)
> > {
> > #define ADD_CONFIG_TERM(__type, __name, __val) \
> > -do { \
> > struct perf_evsel_config_term *__t; \
> > \
> > __t = zalloc(sizeof(*__t)); \
> > @@ -1229,9 +1228,23 @@ do { \
> > \
> > INIT_LIST_HEAD(&__t->list); \
> > __t->type = PERF_EVSEL__CONFIG_TERM_ ## __type; \
> > - __t->val.__name = __val; \
> > __t->weak = term->weak; \
> > - list_add_tail(&__t->list, head_terms); \
> > + list_add_tail(&__t->list, head_terms)
> > +
> > +#define ADD_CONFIG_TERM_VAL(__type, __name, __val) \
> > +do { \
> > + ADD_CONFIG_TERM(__type, __name, __val); \
> > + __t->val.__name = __val; \
> > +} while (0)
> > +
> > +#define ADD_CONFIG_TERM_STR(__type, __name, __val) \
> > +do { \
> > + ADD_CONFIG_TERM(__type, __name, __val); \
> > + __t->val.__name = strdup(__val); \
> > + if (!__t->val.__name) { \
> > + zfree(&__t); \
> > + return -ENOMEM; \
> > + } \
> > } while (0)
>
> hum, I did not check yesterday how we release perf_evsel_config_term
> objects, but looks like now we need to release those pointers in here:
> perf_evsel__free_config_terms

My bad! I did some check for releasing but missed this function.

Will spin a new patch for this. Since '__t->val' is an union type, so
for the releasing, I think we need to use below code.

Please let me know if this is okay for you?

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index a69e64236120..fc659cdbd3ce 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1264,7 +1264,19 @@ static void perf_evsel__free_config_terms(struct evsel *evsel)
struct perf_evsel_config_term *term, *h;

list_for_each_entry_safe(term, h, &evsel->config_terms, list) {
+ int type = term->type;
+
list_del_init(&term->list);
+
+ if (type == PARSE_EVENTS__TERM_TYPE_CALLGRAPH)
+ zfree(&term->val.callgraph);
+
+ if (type == PARSE_EVENTS__TERM_TYPE_BRANCH_SAMPLE_TYPE)
+ zfree(&term->val.branch);
+
+ if (type == PARSE_EVENTS__TERM_TYPE_DRV_CFG)
+ zfree(&term->val.drv_cfg);
+
free(term);
}
}

Thanks,
Leo