Re: [PATCH] tracing: Update create_system_filter() kernel-doc comment

[Steven Rostedt]

On Sat, 20 Mar 2021 11:39:16 +0000
Qiujun Huang <hqjagain@xxxxxxxxx> wrote:

> commit f306cc82a93d ("tracing: Update event filters for multibuffer")
> added the parameter @tr for create_system_filter().
> 
> commit bb9ef1cb7d86 ("tracing: Change apply_subsystem_event_filter() paths to
> check file->system == dir")
> changed the parameter from @system to @dir.
> 
> commit 1e144d73f729 ("tracing: Add trace_array parameter to
> create_event_filter()")
> added the parameter @tr for create_filter().
> 
> Signed-off-by: Qiujun Huang <hqjagain@xxxxxxxxx>
> ---
>  kernel/trace/trace_events_filter.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
> index e91259f6a722..00e78a012de9 100644
> --- a/kernel/trace/trace_events_filter.c
> +++ b/kernel/trace/trace_events_filter.c
> @@ -1693,6 +1693,7 @@ static void create_filter_finish(struct filter_parse_error *pe)
>  
>  /**
>   * create_filter - create a filter for a trace_event_call
> + * @tr: the trace array associated with these events

This looks fine.

>   * @call: trace_event_call to create a filter for
>   * @filter_str: filter string
>   * @set_str: remember @filter_str and enable detailed error in filter
> @@ -1741,8 +1742,9 @@ int create_event_filter(struct trace_array *tr,
>  }
>  
>  /**
> - * create_system_filter - create a filter for an event_subsystem
> - * @system: event_subsystem to create a filter for
> + * create_system_filter - create a filter for an event_subsystem_dir

Do you know what a "event_subsystem_dir" is? I don't.

In fact, the original text makes much more sense. You could remove the
"_" and have it say "event subsystem".


> + * @dir: event_subsystem_dir to create a filter for

I have no idea what the above text even means. @dir is the descriptor
for the system directory.

> + * @tr: the trace array associated with these events
>   * @filter_str: filter string
>   * @filterp: out param for created filter (always updated on return)
>   *

Looking at the code I think it should have another clean up, as where
both @dir and @tr as passed it, it should just pass in @dir, because
@tr is simply @dir->tr.

-- Steve