Re: [PATCH v3 1/6] Documentation: perf: hisi: Documentation for HiSilicon SoC PMU driver

From: Will Deacon
Date: Thu Jul 20 2017 - 09:14:07 EST


On Thu, Jul 20, 2017 at 02:08:47PM +0100, Will Deacon wrote:
> On Thu, Jul 20, 2017 at 08:54:36PM +0800, Zhangshaokun wrote:
> > On 2017/7/19 17:17, Jonathan Cameron wrote:
> > >> +Super CPU cluster (SCCL) and is made up of 6 CCLs. Each SCCL has two HHAs
> > >> +(0 - 1) and four DDRCs (0 - 3), respectively.
> > >> +
> > >> +HiSilicon SoC uncore PMU driver
> > >> +---------------------------------------
> > >> +Each device PMU has separate registers for event counting, control and
> > >> +interrupt, and the PMU driver shall register perf PMU drivers like L3C,
> > >> +HHA and DDRC etc. The available events and configuration options shall
> > >> +be described in the sysfs, see /sys/devices/hisi_*.
> > > Is there not a subsystem directory that would make more sense to
> > > refer to than the full device list?
> > >
> >
> > For uncore devices, it is more reasonable to list in /sys/devices/***.
>
> The usual place for these things is /sys/bus/event_source/devices/<pmu name>.

... which are symlinks to directories under /sys/devices/! I didn't realise
that, so I suspect you're ok. Still worth getting the format of things
correct though, so perf can read/parse them with minimal effort.

Will