Re: [PATCH v2 21/21] perf metric: Allow modifiers on metrics.

From: Ian Rogers
Date: Tue Oct 19 2021 - 16:00:40 EST


On Tue, Oct 19, 2021 at 8:18 AM Arnaldo Carvalho de Melo
<acme@xxxxxxxxxx> wrote:
>
> Em Tue, Oct 19, 2021 at 12:17:10PM -0300, Arnaldo Carvalho de Melo escreveu:
> > Em Tue, Oct 19, 2021 at 12:13:52PM -0300, Arnaldo Carvalho de Melo escreveu:
> > > Em Tue, Oct 19, 2021 at 12:06:17PM -0300, Arnaldo Carvalho de Melo escreveu:
> > > > Em Fri, Oct 15, 2021 at 10:21:32AM -0700, Ian Rogers escreveu:
> > > > > By allowing modifiers on metrics we can, for example, gather the
> > > > > same metric for kernel and user mode. On a SkylakeX with
> > > > > TopDownL1 this gives:
> > > > >
> > > > > $ perf stat -M TopDownL1:u,TopDownL1:k -a sleep 2
> > > > >
> > > > > Performance counter stats for 'system wide':
> > > >
> > > > Hi Ian, can you please take a look on this? this is on my perf/core
> > > > branch.
> > >
> > > I processed the first version of this series, reviewed by Andi, can you
> > > please submit the diff from one to the other?
> >
> > The interdiff from the 21st patch on the first batch versus on the v2
> > batch is below, but it doesn't apply to my current perf/core branch,
> > lemme push it to tmp.perf/core...
>
> It was there already, what I have locally is what is in tmp.perf/core.

Hi Arnaldo,

The last change I see in tmp.perf/core is:
https://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git/commit/?h=tmp.perf/core&id=5f43061b84d815c0f6477c1a8836bf0c6fec15a2

The difference between v2 and v1 which fixes this bug is:

+@@ -1500,7 +1568,10 @@ int metricgroup__copy_metric_events(struct
evlist *evlist, struct cgroup *cgrp,
+ return -ENOMEM;
+
+ new_expr->metric_expr = old_expr->metric_expr;
+- new_expr->metric_name = old_expr->metric_name;
++ new_expr->metric_name = strdup(old_expr->metric_name);
++ if (!new_expr->metric_name)
++ return -ENOMEM;
++
+ new_expr->metric_unit = old_expr->metric_unit;
+ new_expr->runtime = old_expr->runtime;
+

I also cleaned up some checkpatch line length warnings in v2, which I
think is the reason for the other changes. Ideally I'd prefer the v2
patch set over the v1, but they are largely identical. Both were based
on acme/perf/core. Let me know how I can help.

Thanks,
Ian

> > - Arnaldo
> >
> > ⬢[acme@toolbox perf]$ interdiff ~/wb/old.patch ~/wb/new.patch
> > diff -u b/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
> > --- b/tools/perf/util/metricgroup.c
> > +++ b/tools/perf/util/metricgroup.c
> > @@ -1308,8 +1308,7 @@
> > int ret;
> >
> > *out_evlist = NULL;
> > - ret = metricgroup__build_event_string(&events, ids, modifier,
> > - has_constraint);
> > + ret = metricgroup__build_event_string(&events, ids, has_constraint);
> > if (ret)
> > return ret;
> >
> > @@ -1324,7 +1323,8 @@
> >
> > ids__insert(ids->ids, tmp);
> > }
> > - ret = metricgroup__build_event_string(&events, ids, has_constraint);
> > + ret = metricgroup__build_event_string(&events, ids, modifier,
> > + has_constraint);
> > if (ret)
> > return ret;
> >
> > @@ -1568,7 +1568,10 @@
> > return -ENOMEM;
> >
> > new_expr->metric_expr = old_expr->metric_expr;
> > - new_expr->metric_name = old_expr->metric_name;
> > + new_expr->metric_name = strdup(old_expr->metric_name);
> > + if (!new_expr->metric_name)
> > + return -ENOMEM;
> > +
> > new_expr->metric_unit = old_expr->metric_unit;
> > new_expr->runtime = old_expr->runtime;
> >
> > ⬢[acme@toolbox perf]$
>
> --
>
> - Arnaldo