Re: [PATCH v5 1/4]: perf/core: use rb trees for pinned/flexible groups

[Alexey Budankov]

Hi,

On 18.07.2017 15:02, Alexander Shishkin wrote:
> Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx> writes:
> 
>> +static void
>> +perf_event_groups_rotate(struct perf_event_groups *groups, int cpu)
>> +{
>> +	struct rb_node *node;
>> +	struct perf_event *node_event;
>> +
>> +	WARN_ON_ONCE(!groups);
> 
> This seems redundant.

Used that for debugging.

> 
>> +
>> +	list_rotate_left(&groups->list);
>> +
>> +	/* will replace rotation above in patch v5 3/4
>> +
>> +	node = groups->tree.rb_node;
>> +
>> +	while (node) {
>> +		node_event = container_of(node,
>> +				struct perf_event, group_node);
>> +
>> +		if (cpu < node_event->cpu) {
>> +			node = node->rb_left;
>> +		} else if (cpu > node_event->cpu) {
>> +			node = node->rb_right;
>> +		} else {
>> +			list_rotate_left(&node_event->group_list);
>> +			break;
>> +		}
>> +	}
>> +
>> +	*/
> 
> Please don't do this, it doesn't add clarity.

Accepted. Put it here just for review process simplification.

> 
>> +static int
>> +perf_event_groups_iterate(struct perf_event_groups *groups,
>> +		perf_event_groups_iterate_f callback, void *data)
>> +{
>> +	int ret = 0;
>> +	struct perf_event *event;
>> +
>> +	WARN_ON_ONCE(!groups);
>> +
>> +	list_for_each_entry(event, &groups->list, group_list_entry) {
>> +		ret = callback(event, data);
>> +		if (ret)
>> +			break;
>> +	}
>> +
>> +	/* will replace itration above in patch v5 4/4
>> +
>> +	for (node = rb_first(groups); node; node = rb_next(node)) {
>> +		node_event = container_of(node,	struct perf_event, group_node);
>> +		list_for_each_entry(event, &node_event->group_list,
>> +				group_list_entry) {
>> +			WARN_ON_ONCE(!(event->cpu == node_event->cpu));
>> +			ret = callback(event, data);
>> +			if (ret) {
>> +				return ret;
>> +			}
>> +		}
>> +	}
>> +
>> +	*/
> 
> Ditto.
> 
> Regards,
> --
> Alex
> 

Thanks,
Alexey