RE: perf top for arm64?

[Joakim Zhang <qiangqing.zhang@nxp.com>]

> -----Original Message-----
> From: linux-perf-users-owner@vger.kernel.org
> <linux-perf-users-owner@vger.kernel.org> On Behalf Of Jiri Olsa
> Sent: 2019年12月11日 1:09
> To: John Garry <john.garry@huawei.com>
> Cc: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>;
> peterz@infradead.org; mingo@redhat.com;
> alexander.shishkin@linux.intel.com; namhyung@kernel.org;
> mark.rutland@arm.com; will@kernel.org; linux-kernel@vger.kernel.org;
> linux-arm-kernel@lists.infradead.org; Linuxarm <linuxarm@huawei.com>;
> linux-perf-users@vger.kernel.org
> Subject: Re: perf top for arm64?
> 
> On Tue, Dec 10, 2019 at 04:52:52PM +0000, John Garry wrote:
> > On 10/12/2019 16:36, Jiri Olsa wrote:
> > > On Tue, Dec 10, 2019 at 04:13:49PM +0000, John Garry wrote:
> > > > Hi all,
> > > >
> > > > I find to my surprise that "perf top" does not work for arm64:
> > > >
> > > > root@ubuntu:/home/john/linux# tools/perf/perf top Couldn't read
> > > > the cpuid for this machine: No such file or directory
> > >
> >
> > Hi Jirka,
> >
> > > there was recent change that check on cpuid and quits:
> > >    608127f73779 perf top: Initialize perf_env->cpuid, needed by the
> > > per arch annotation init routine
> > >
> >
> > ok, this is new code. I obviously didn't check the git history...
> >
> > But, apart from this, there are many other places where get_cpuid() is
> > called. I wonder what else we're missing out on, and whether we should
> > still add it.
> 
> right, I was just wondering how come vendor events are working for you, but
> realized we have get_cpuid_str being called in there ;-)
> 
> I think we should add it as you have it prepared already, could you post it with
> bigger changelog that would explain where it's being used for arm?

Hi Jirka,

I reported metricgroup cannot work on ARM64 before, however, no one can come up with a solution, could you take a look how to fix it? Thanks a lot!

You can refer to below link for more info:
	[1] https://www.spinics.net/lists/linux-perf-users/msg09190.html (NACK by Will Deason)
	[2] https://www.spinics.net/lists/linux-perf-users/msg09324.html

Best Regards,
Joakim Zhang
> jirka