Re: [PATCH 3/3] arm64 cpuinfo: implement sysfs nodes for arm64

From: Greg KH
Date: Tue Dec 10 2019 - 09:47:42 EST


On Tue, Dec 10, 2019 at 02:33:07PM +0100, Thomas Renninger wrote:
> On Monday, December 9, 2019 6:38:05 PM CET Will Deacon wrote:
> > On Mon, Dec 09, 2019 at 12:28:44PM +0100, Thomas Renninger wrote:
> > > On Monday, December 9, 2019 11:31:11 AM CET Will Deacon wrote:
> > > > On Fri, Dec 06, 2019 at 05:24:21PM +0100, Thomas Renninger wrote:
> > > > > From: Felix Schnizlein <fschnizlein@xxxxxxx>
> > > > >
> > > > > Export all information from /proc/cpuinfo to sysfs:
> > > > > implementer, architecture, variant, part, revision,
> > > > > bogomips and flags are exported.
> > > > >
> > > > > Example:
> > > > > /sys/devices/system/cpu/cpu1/info/:[0]# head *
> > >
> > > ...
> > >
> > > > > ==> flags <==
> > > > > fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid asimdrdm
> > >
> > > ...
> > >
> > > > I don't understand why we need this on arm64
>
> Again: proc is moving to sys.

No. New stuff is to be added to /sys/, don't add new things to /proc
unless it deals with processes.

There is no mass-migration of existing /proc files to sysfs for no good
reason.

> You probably export feature flags in /proc/cpuinfo for a good reason.
> So where in sysfs should this show up?

Why does it have to live in sysfs if it is already in /proc and parsed
properly by tools?

thanks,

greg k-h