Re: [PATCH] hwmon: (coretemp) remove duplicated coretemp for same core id

From: Shu Wang
Date: Thu Oct 19 2017 - 06:10:14 EST


> From: "Thomas Gleixner" <tglx@xxxxxxxxxxxxx>
> To: "Guenter Roeck" <linux@xxxxxxxxxxxx>
> Cc: "Shu Wang" <shuwang@xxxxxxxxxx>, "fenghua yu" <fenghua.yu@xxxxxxxxx>, jdelvare@xxxxxxxx,
> linux-hwmon@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, chuhu@xxxxxxxxxx, yizhan@xxxxxxxxxx
> Sent: Thursday, October 19, 2017 4:02:50 PM
> Subject: Re: [PATCH] hwmon: (coretemp) remove duplicated coretemp for same core id
>
> On Wed, 18 Oct 2017, Guenter Roeck wrote:
> > On 10/18/2017 07:28 PM, Shu Wang wrote:
>
> > > > > > > Fix kernel warning on my 4cpus 2core_id system. The cpu0 and cpu1
> > > > > > > have same core_id 0, so both cpu0 and cpu1 will try to create
> > > > > > > file
> > > > > > > temp2_label when it's online.
> > > > > > >
> > > > > >
> > > > > > > - coretemp_cpu_online(cpu=0)
> > > > > > > - create_core_data(cpu=0, attr_no=2)
> > > > > > > - create_core_attrs(attr_no=2)
> > > > > > > - coretemp_cpu_online(cpu=1)
> > > > > > > - create_core_data(cpu=1, attr_no=2)
> > > > > > > - create_core_attrs(attr_no=2)
> > > > > > >
> > > > > > > $ grep -e processor -e 'core id' /proc/cpuinfo
> > > > > > > processor : 0
> > > > > > > core id : 0
> > > > > > > processor : 1
> > > > > > > core id : 0
> > > > > > > processor : 2
> > > > > > > core id : 1
> > > > > > > processor : 3
> > > > > > > core id : 1
> > > > > >
> > > > > > Complete output of /proc/cpuinfo might be helpful.
> > > > >
> > > > > $ cat /proc/cpuinfo
> > > > > processor : 0
> > > > > vendor_id : GenuineIntel
> > > > > cpu family : 6
> > > > > model : 61
> > > > > model name : Intel(R) Core(TM) i7-5600U CPU @ 2.60GHz
> > > >
> > > > This is a hyperthreading CPU, which should already be handled,
> > >
> > > Do you mean that for my system, coretemp_cpu_online should only
> > > be called twice instead of four times to create two core attrs?
> > >
> >
> > coretemp_add_core() should only be called twice, and cpumask_intersects()
> > should filter out the duplicate ones.
> >
> > /*
> > * Check whether a thread sibling is already online. If not add the
> > * interface for this CPU core.
> > */
> > if (!cpumask_intersects(&pdata->cpumask,
> > topology_sibling_cpumask(cpu)))
> > coretemp_add_core(pdev, cpu, 0);
> >
> > Thomas, is it possible that something is wrong with this code ?

Sorry, I got the root cause, not coretemp's problem. I enabled numa=fake=2
cmdline param to simulate 2 nodes on my systems. 2 threads of the a same core
happened to be on different node, so they are not siblings.

Thanks for you reply

>
> Hrmm. Not that I can see. The only thing I can think of is that the logical
> package association of the CPUs is screwed.
>
> Debug patch below.
>
> Thanks,