Subject: Re: [PATCH] tracing: Set user_events to BROKEN

From: Mathieu Desnoyers <[email-masked]>
Date: Wed, 30 Mar 2022 12:54:13 -0400 (EDT)

----- On Mar 29, 2022, at 10:25 PM, rostedt [email-masked] wrote:

> From: "Steven Rostedt (Google)" <[email-masked]>
> 
> After being merged, user_events become more visible to a wider audience
> that have concerns with the current API. It is too late to fix this for
> this release, but instead of a full revert, just mark it as BROKEN (which
> prevents it from being selected in make config). Then we can work finding
> a better API. If that fails, then it will need to be completely reverted.

Hi Steven,

What are the constraints for changing a uapi header after it has been present
in a kernel release ?

If we are not ready to commit to an ABI, perhaps it would be safer to ensure
that include/uapi/linux/user_events.h is not installed with the uapi headers
until it's ready.

Thanks,

Mathieu

> 
> Link:
> https://lore.kernel.org/all/[email-masked]/
> 
> Signed-off-by: Steven Rostedt (Google) <[email-masked]>
> ---
> kernel/trace/Kconfig | 1 +
> 1 file changed, 1 insertion(+)
> 
> diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
> index 16a52a71732d..edc8159f63ef 100644
> --- a/kernel/trace/Kconfig
> +++ b/kernel/trace/Kconfig
> @@ -741,6 +741,7 @@ config USER_EVENTS
> 	bool "User trace events"
> 	select TRACING
> 	select DYNAMIC_EVENTS
> +	depends on BROKEN # API needs to be straighten out
> 	help
> 	  User trace events are user-defined trace events that
> 	  can be used like an existing kernel trace event.  User trace
> --
> 2.35.1

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com