Re: [RFC PATCH 16/19] mm/damon: trace probe_hits

[SeongJae Park]

On Tue, 28 Apr 2026 14:17:45 -0400 Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> On Sun, 26 Apr 2026 13:52:17 -0700
> SeongJae Park <sj@xxxxxxxxxx> wrote:
> 
> > Introduce a new tracepoint for exposing the per-region per-probe
> > positive sample count via tracefs.
> > 
> > Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
> > ---
> >  include/trace/events/damon.h | 41 ++++++++++++++++++++++++++++++++++++
> >  mm/damon/core.c              |  1 +
> >  2 files changed, 42 insertions(+)
> > 
> > diff --git a/include/trace/events/damon.h b/include/trace/events/damon.h
> > index 7e25f4469b81b..121d7bc3a2c27 100644
> > --- a/include/trace/events/damon.h
> > +++ b/include/trace/events/damon.h
> > @@ -130,6 +130,47 @@ TRACE_EVENT(damon_monitor_intervals_tune,
> >  	TP_printk("sample_us=%lu", __entry->sample_us)
> >  );
> >  
> > +TRACE_EVENT(damon_aggregated_v2,
> > +
> > +	TP_PROTO(unsigned int target_id, struct damon_region *r,
> > +		unsigned int nr_regions),
> > +
> > +	TP_ARGS(target_id, r, nr_regions),
> > +
> > +	TP_STRUCT__entry(
> > +		__field(unsigned long, target_id)
> > +		__field(unsigned int, nr_regions)
> 
> Move the nr_regions to after "end" as on 64 bit machines, this creates a 4
> byte hole.

Thank you for the nice suggestion, Steven.  Will do so in the next version.


Thanks,
SJ

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