Re: [RFC PATCH 0/5] Generic IPI sending tracepoint

[Steven Rostedt]

On Fri, 7 Oct 2022 17:01:33 -0300
Marcelo Tosatti <mtosatti@xxxxxxxxxx> wrote:

> > As for the targeted CPUs, the existing tracepoint does export them, albeit in
> > cpumask form, which is quite inconvenient from a tooling perspective. For
> > instance, as far as I'm aware, it's not possible to do event filtering on a
> > cpumask via trace-cmd.  
> 
> https://man7.org/linux/man-pages/man1/trace-cmd-set.1.html
> 
>        -f filter
>            Specify a filter for the previous event. This must come after
>            a -e. This will filter what events get recorded based on the
>            content of the event. Filtering is passed to the kernel
>            directly so what filtering is allowed may depend on what
>            version of the kernel you have. Basically, it will let you
>            use C notation to check if an event should be processed or
>            not.
> 
>                ==, >=, <=, >, <, &, |, && and ||
> 
>            The above are usually safe to use to compare fields.

We could always add an "isset(x)" filter ;-)

-- Steve