static int arc_pmu_event_init()

in kernel/perf_event.c [329:387]

• 47 lines of code
• 12 McCabe index (conditional complexity)

static int arc_pmu_event_init(struct perf_event *event)
{
	struct hw_perf_event *hwc = &event->hw;
	int ret;

	if (!is_sampling_event(event)) {
		hwc->sample_period = arc_pmu->max_period;
		hwc->last_period = hwc->sample_period;
		local64_set(&hwc->period_left, hwc->sample_period);
	}

	hwc->config = 0;

	if (is_isa_arcv2()) {
		/* "exclude user" means "count only kernel" */
		if (event->attr.exclude_user)
			hwc->config |= ARC_REG_PCT_CONFIG_KERN;

		/* "exclude kernel" means "count only user" */
		if (event->attr.exclude_kernel)
			hwc->config |= ARC_REG_PCT_CONFIG_USER;
	}

	switch (event->attr.type) {
	case PERF_TYPE_HARDWARE:
		if (event->attr.config >= PERF_COUNT_HW_MAX)
			return -ENOENT;
		if (arc_pmu->ev_hw_idx[event->attr.config] < 0)
			return -ENOENT;
		hwc->config |= arc_pmu->ev_hw_idx[event->attr.config];
		pr_debug("init event %d with h/w %08x \'%s\'\n",
			 (int)event->attr.config, (int)hwc->config,
			 arc_pmu_ev_hw_map[event->attr.config]);
		return 0;

	case PERF_TYPE_HW_CACHE:
		ret = arc_pmu_cache_event(event->attr.config);
		if (ret < 0)
			return ret;
		hwc->config |= arc_pmu->ev_hw_idx[ret];
		pr_debug("init cache event with h/w %08x \'%s\'\n",
			 (int)hwc->config, arc_pmu_ev_hw_map[ret]);
		return 0;

	case PERF_TYPE_RAW:
		if (event->attr.config >= arc_pmu->n_events)
			return -ENOENT;

		hwc->config |= event->attr.config;
		pr_debug("init raw event with idx %lld \'%s\'\n",
			 event->attr.config,
			 arc_pmu->raw_entry[event->attr.config].name);

		return 0;

	default:
		return -ENOENT;
	}
}