Re: [PATCH v4 2/2] ThunderX2: Add Cavium ThunderX2 SoC UNCORE PMU driver

From: Mark Rutland
Date: Fri Apr 27 2018 - 05:30:41 EST

Hi Kim,

On Thu, Apr 26, 2018 at 05:06:24PM -0500, Kim Phillips wrote:
> On Wed, 25 Apr 2018 14:30:47 +0530
> Ganapatrao Kulkarni <ganapatrao.kulkarni@xxxxxxxxxx> wrote:
> > +static int thunderx2_uncore_event_init(struct perf_event *event)

> This PMU driver can be made more user-friendly by not just silently
> returning an error code such as -EINVAL, but by emitting a useful
> message describing the specific error via dmesg.

As has previously been discussed on several occasions, patches which log
to dmesg in a pmu::event_init() path at any level above pr_debug() are
not acceptable -- dmesg is not intended as a mechanism to inform users
of driver-specific constraints.

I would appreciate if in future you could qualify your suggestion with
the requirement that pr_debug() is used.