Re: [PATCH v4 2/3] perf tools: parse the pmu event prefix and surfix

[Jiri Olsa <jolsa@redhat.com>]

On Tue, Sep 02, 2014 at 11:29:29AM -0400, kan.liang@intel.com wrote:
> From: Kan Liang <kan.liang@intel.com>

SNIP

> + * Read the pmu events list from sysfs
> + * Save it into kernel_pmu_events_list
> + */
> +static void scan_kernel_pmu_events_list(void)
> +{
> +
> +	struct perf_pmu *pmu = NULL;
> +	struct perf_pmu_alias *alias;
> +	int len = 0;
> +
> +	while ((pmu = perf_pmu__scan(pmu)) != NULL)
> +		list_for_each_entry(alias, &pmu->aliases, list) {

Why do we need to call scan here? Looks like:
  pmu = pmu_lookup("cpu")

should be enough.. and could be used below as well

> +			if (!strcmp(pmu->name, "cpu")) {
> +				if (strchr(alias->name, '-'))
> +					len++;
> +				len++;
> +			}
> +	}
> +	if (len == 0)
> +		return;
> +	kernel_pmu_events_list =
> +		malloc(sizeof(struct kernel_pmu_event_symbol) * len);
> +	kernel_pmu_events_list_num = len;
> +
> +	pmu = NULL;
> +	len = 0;
> +	while ((pmu = perf_pmu__scan(pmu)) != NULL)
> +		list_for_each_entry(alias, &pmu->aliases, list) {
> +			if (!strcmp(pmu->name, "cpu")) {
> +				struct kernel_pmu_event_symbol *p =
> +					kernel_pmu_events_list + len;
> +				char *tmp = strchr(alias->name, '-');
> +
> +				if (tmp != NULL) {
> +					strlcpy(p->symbol, alias->name,
> +						tmp - alias->name + 1);
> +					p->type = KERNEL_PMU_EVENT_PREFIX;
> +					tmp++;
> +					p++;
> +					strcpy(p->symbol, tmp);
> +					p->type = KERNEL_PMU_EVENT_SUFFIX;
> +					len += 2;
> +				} else {
> +					strcpy(p->symbol, alias->name);
> +					p->type = KERNEL_PMU_EVENT;
> +					len++;
> +				}
> +			}
> +		}
> +	qsort(kernel_pmu_events_list, len,
> +		sizeof(struct kernel_pmu_event_symbol), comp_pmu);
> +
> +}

SNIP

thanks,
jirka