Re: [RFC] perf/jevents: Add new structure to pass json fields.

Jiri Olsa
2020-08-26T11:00:28Z

On Tue, Aug 25, 2020 at 01:10:41PM +0530, Kajol Jain wrote:

SNIP

> {
> /* try to find matching event from arch standard values */
> struct event_struct *es;
> @@ -498,8 +486,7 @@ try_fixup(const char *fn, char *arch_std, char **event, char **desc,
> if (!strcmp(arch_std, es->name)) {
> if (!eventcode && es->event) {
> /* allow EventCode to be overridden */
> - free(*event);
> - *event = NULL;
> + je->event = NULL;
> }
> FOR_ALL_EVENT_STRUCT_FIELDS(TRY_FIXUP_FIELD);
> return 0;
> @@ -513,13 +500,8 @@ try_fixup(const char *fn, char *arch_std, char **event, char **desc,
>
> /* Call func with each event in the json file */
> int json_events(const char *fn,
> - int (*func)(void *data, char *name, char *event, char *desc,
> - char *long_desc,
> - char *pmu, char *unit, char *perpkg,
> - char *metric_expr,
> - char *metric_name, char *metric_group,
> - char *deprecated, char *metric_constraint),
> - void *data)
> + int (*func)(void *data, struct json_event *je),
> + void *data)
> {
> int err;
> size_t size;
> @@ -537,24 +519,16 @@ int json_events(const char *fn,
> EXPECT(tokens->type == JSMN_ARRAY, tokens, "expected top level array");
> tok = tokens + 1;
> for (i = 0; i < tokens->size; i++) {
> - char *event = NULL, *desc = NULL, *name = NULL;
> - char *long_desc = NULL;
> char *extra_desc = NULL;
> - char *pmu = NULL;
> char *filter = NULL;
> - char *perpkg = NULL;
> - char *unit = NULL;
> - char *metric_expr = NULL;
> - char *metric_name = NULL;
> - char *metric_group = NULL;
> - char *deprecated = NULL;
> - char *metric_constraint = NULL;
> + struct json_event *je;
> char *arch_std = NULL;
> unsigned long long eventcode = 0;
> struct msrmap *msr = NULL;
> jsmntok_t *msrval = NULL;
> jsmntok_t *precise = NULL;
> jsmntok_t *obj = tok++;
> + je = (struct json_event *)calloc(1, sizeof(struct json_event));

hum, you don't check je pointer in here.. but does it need to be allocated?
looks like you could just have je on stack as well..

thanks,
jirka