Re: [PATCH v2 2/6] perf test: Handle metric reuse in pmu-events parsing test

Jiri Olsa
2021-04-01T18:07:02Z

On Thu, Mar 25, 2021 at 06:33:14PM +0800, John Garry wrote:

SNIP

> +struct metric {
> + struct list_head list;
> + struct metric_ref metric_ref;
> +};
> +
> +static int resolve_metric_simple(struct expr_parse_ctx *pctx,
> + struct list_head *compound_list,
> + struct pmu_events_map *map,
> + const char *metric_name)
> +{
> + struct hashmap_entry *cur, *cur_tmp;
> + struct metric *metric, *tmp;
> + size_t bkt;
> + bool all;
> + int rc;
> +
> + do {
> + all = true;
> + hashmap__for_each_entry_safe((&pctx->ids), cur, cur_tmp, bkt) {
> + struct metric_ref *ref;
> + struct pmu_event *pe;
> +
> + pe = metrcgroup_find_metric(cur->key, map);
> + if (!pe)
> + continue;
> +
> + if (!strcmp(metric_name, (char *)cur->key)) {
> + pr_warning("Recursion detected for metric %s\n", metric_name);
> + rc = -1;
> + goto out_err;
> + }
> +
> + all = false;
> +
> + /* The metric key itself needs to go out.. */
> + expr__del_id(pctx, cur->key);
> +
> + metric = malloc(sizeof(*metric));
> + if (!metric) {
> + rc = -ENOMEM;
> + goto out_err;
> + }
> +
> + ref = &metric->metric_ref;
> + ref->metric_name = pe->metric_name;
> + ref->metric_expr = pe->metric_expr;
> + list_add_tail(&metric->list, compound_list);
> +
> + rc = expr__find_other(pe->metric_expr, NULL, pctx, 0);

so this might add new items to pctx->ids, I think you need
to restart the iteration as we do it in __resolve_metric
otherwise you could miss some new keys

jirka

> + if (rc)
> + goto out_err;
> + }
> + } while (!all);
> +
> + return 0;
> +
> +out_err:
> + list_for_each_entry_safe(metric, tmp, compound_list, list)
> + free(metric);
> +
> + return rc;
> +
> +}

SNIP