Re: [PATCH v3 1/4] tracing/user_events: Prepare find/delete for same name events

From: Steven Rostedt
Date: Wed Feb 21 2024 - 10:15:42 EST


On Wed, 14 Feb 2024 17:50:43 +0000
Beau Belgrave <beaub@xxxxxxxxxxxxxxxxxxx> wrote:

So the patches look good, but since I gave you some updates, I'm now going
to go though "nits". Like grammar and such ;-)

> The current code for finding and deleting events assumes that there will
> never be cases when user_events are registered with the same name, but
> different formats. In the future this scenario will exist to ensure

> user programs can be updated or modify their events and run different
> versions of their programs side-by-side without being blocked.

Can you change the last sentence above. I read it three times and it's
still awkward to understand it. Particularly, the "user programs can be
updated or modify their events". That just doesn't want to compute.

>
> This change does not yet allow for multi-format events. If user_events
> are registered with the same name but different arguments the programs
> see the same return values as before. This change simply makes it
> possible to easily accomodate for this in future changes.

I think you can drop the "in future changes" part.

>
> Update find_user_event() to take in argument parameters and register
> flags to accomodate future multi-format event scenarios. Have find
> validate argument matching and return error pointers to cover address
> in use cases, or allocation errors. Update callers to handle error

"to cover address in use cases" ?

> pointer logic.
>
> Move delete_user_event() to use hash walking directly now that find has
> changed. Delete all events found that match the register name, stop

"now that find has changed" ? You mean the "find function"?

> if an error occurs and report back to the user.
>
> Update user_fields_match() to cover list_empty() scenarios instead of
> each callsite doing it now that find_user_event() uses it directly.

The above is a bit of a run-on sentence.

-- Steve

>
> Signed-off-by: Beau Belgrave <beaub@xxxxxxxxxxxxxxxxxxx>
> ---