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

Steven Rostedt
2022-10-08T19:40:41Z

On Fri, 7 Oct 2022 17:01:33 -0300
Marcelo Tosatti <mtosatti@redhat.com> 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