Re: [PATCH v3 2/3] tracing: Add trace_irqsoff tracepoints

[Steven Rostedt]

On Tue, 30 Aug 2016 15:11:26 +0530
Binoy Jayan <binoy.jayan@xxxxxxxxxx> wrote:

> On 29 August 2016 at 15:13, Daniel Wagner <daniel.wagner@xxxxxxxxxxxx> wrote:
> > Hi Binoy,
> >
> > Some minor nitpicking.
> >
> > As Steven already pointed out, the cpu field is available in all traces.
> > It's one of the predefined fields (see
> > kernel/trace/trace_events.c/trace_define_generic_fields()). Just drop it.
> >  
> 
> Hi Daniel,
> 
> Thank you for looking at the patch again. When I do not use cpu as a field,
> I am not able to make it part of the key or value fields. I can only
> use cpu in the
> filter predicate.
> 
> For example, the following trigger does not seem to work:
> 'hist:key=ltype,cpu:val=latency:sort=ltype,cpu if ltype==0'
> 
> But the following works:
> 'hist:key=ltype,latency:val=hitcount:sort=latency if cpu==1'

What about using "CPU" (all caps)? Look at
kernel/trace/trace_events_filter.c for FILTER_CPU.

Lets not add fields when we can fix the generic code to process these.

Thanks!

-- Steve