Re: [PATCH] perf record/arm-spe: Override attr->sample_period for non-libpfm4 events

From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: German Gomez <german.gomez@arm.com>
Cc: Ian Rogers <irogers@google.com>,
	James Clark <james.clark@arm.com>,
	linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org,
	Chase Conklin <chase.conklin@arm.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>,
	Martin KaFai Lau <kafai@fb.com>, Song Liu <songliubraving@fb.com>,
	Yonghong Song <yhs@fb.com>,
	John Fastabend <john.fastabend@gmail.com>,
	KP Singh <kpsingh@kernel.org>,
	Arnaldo Carvalho de Melo <acme@redhat.com>,
	Stephane Eranian <eranian@google.com>,
	netdev@vger.kernel.org, bpf@vger.kernel.org
Subject: Re: [PATCH] perf record/arm-spe: Override attr->sample_period for non-libpfm4 events
Date: Sat, 22 Jan 2022 17:15:01 -0300	[thread overview]
Message-ID: <Yexlxe0JHgj4ndSQ@kernel.org> (raw)
In-Reply-To: <YeazXmnjkET7h5LW@kernel.org>

Em Tue, Jan 18, 2022 at 09:32:30AM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Mon, Jan 17, 2022 at 09:32:55PM +0000, German Gomez escreveu:
> > Hi Ian,
> > 
> > On 17/01/2022 16:28, Ian Rogers wrote:
> > > [...]
> > > Thanks for fixing this, I can add an acked-by for the v2 patch. Could
> > > we add a test for this to avoid future regressions? There are similar
> > > tests for frequency like:
> > > https://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git/tree/tools/perf/tests/attr/test-record-freq
> > > based on the attr.py test:
> > > https://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git/tree/tools/perf/tests/attr.py
> > > The test specifies a base type of event attribute and then what is
> > > modified by the test. It takes a little to get your head around but
> > > having a test for this would be a welcome addition.
> > 
> > I agree I should have included a test for this fix. I'll look into this for the v2.
> 
> A test is always good to have, we need more, yeah.
> 
> But since this is a fix and what is needed for v2 is just to improve the
> wording, please don't let the test to prevent you from sending the
> updated fix.
> 
> Then you can go on and work on the test.
> 
> I say this because the merge window may close before the test gets ready
> and its better for us to have fixes merged as soon as possible so that
> we have more time to figure out if it has unintended consequences as it
> gets in place for longer.

So, any news about this?

- ARnaldo

> > Other events such as "-p 10000 -e cycles//" worked fine. Only the ones with aux area tracing (arm_spe, cs_etm, intel_pt) were ignoring the global config flags.
> > 
> > Thank you for the pointers, and the review,
> > German