Re: [PATCH 2/4] tracing/user_events: Introduce multi-format events

From: Steven Rostedt
Date: Mon Jan 29 2024 - 21:28:00 EST


On Mon, 29 Jan 2024 09:29:07 -0800
Beau Belgrave <beaub@xxxxxxxxxxxxxxxxxxx> wrote:

> Thanks, yeah ideally we wouldn't use special characters.
>
> I'm not picky about this. However, I did want something that clearly
> allowed a glob pattern to find all versions of a given register name of
> user_events by user programs that record. The dot notation will pull in
> more than expected if dotted namespace style names are used.
>
> An example is "Asserts" and "Asserts.Verbose" from different programs.
> If we tried to find all versions of "Asserts" via glob of "Asserts.*" it
> will pull in "Asserts.Verbose.1" in addition to "Asserts.0".

Do you prevent brackets in names?

>
> While a glob of "Asserts.[0-9]" works when the unique ID is 0-9, it
> doesn't work if the number is higher, like 128. If we ever decide to
> change the ID from an integer to say hex to save space, these globs
> would break.
>
> Is there some scheme that fits the C-variable name that addresses the
> above scenarios? Brackets gave me a simple glob that seemed to prevent a
> lot of this ("Asserts.\[*\]" in this case).

Prevent a lot of what? I'm not sure what your example here is.

>
> Are we confident that we always want to represent the ID as a base-10
> integer vs a base-16 integer? The suffix will be ABI to ensure recording
> programs can find their events easily.

Is there a difference to what we choose?

-- Steve