Re: [PATCH RFV v2 05/13] perf/core: Add function perf_event_create_group_kernel_counters()

[Peter Zijlstra <peterz@infradead.org>]

On Tue, Aug 08, 2023 at 02:31:03PM +0800, Dapeng Mi wrote:
> diff --git a/kernel/events/core.c b/kernel/events/core.c
> index 15eb82d1a010..1877171e9590 100644
> --- a/kernel/events/core.c
> +++ b/kernel/events/core.c
> @@ -12762,11 +12762,34 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
>  				 struct task_struct *task,
>  				 perf_overflow_handler_t overflow_handler,
>  				 void *context)
> +{
> +	return perf_event_create_group_kernel_counters(attr, cpu, task,
> +			NULL, overflow_handler, context);
> +}
> +EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter);
> +
> +/**
> + * perf_event_create_group_kernel_counters
> + *
> + * @attr: attributes of the counter to create
> + * @cpu: cpu in which the counter is bound
> + * @task: task to profile (NULL for percpu)
> + * @group_leader: the group leader event of the created event
> + * @overflow_handler: callback to trigger when we hit the event
> + * @context: context data could be used in overflow_handler callback
> + */
> +struct perf_event *
> +perf_event_create_group_kernel_counters(struct perf_event_attr *attr,
> +					int cpu, struct task_struct *task,
> +					struct perf_event *group_leader,
> +					perf_overflow_handler_t overflow_handler,
> +					void *context)

I would much prefer if you just add the argument to
perf_event_create_kernel_counter(), there aren't *that* many users.