Re: [PATCH v2 02/12] timekeeping: add API for getting timekeeping_suspended

From: John Stultz
Date: Wed Sep 29 2021 - 16:46:22 EST


On Wed, Sep 29, 2021 at 1:01 PM Will McVicker <willmcvicker@xxxxxxxxxx> wrote:
> On Tue, Sep 28, 2021 at 8:42 PM John Stultz <john.stultz@xxxxxxxxxx> wrote:
> > On Tue, Sep 28, 2021 at 4:56 PM Will McVicker <willmcvicker@xxxxxxxxxx> wrote:
> > >
> > > This allows modules to access the value of timekeeping_suspended without
> > > giving them write access to the variable.
> > >
> >
> > It's important to cover "the why" not "the what" in these commit
> > messages, so you might add a note as to what code will be the user of
> > this (the samsung/clk-pll.c code changed later in this series).
> >
> > thanks
> > -john
>
> Thanks John for the tip. I will try to be better at that in the followup.

I have to remind myself regularly as well. :) Apologies if my quick
reply above seemed curt (as it does to me re-reading it now). Wasn't
my intent.

> For this specific patch, I am adding this new API because the Samsung
> PLL driver (drivers/clk/samsung/clk-pll.c) currently is using the
> variable 'timekeeping_suspended' to detect timeouts before the
> clocksource is initialized or timekeeping itself is suspended. My
> patch series aims to modularize the Samsung PLL driver. So to keep the
> driver's functionality intact, I need to add this additional API.

Sounds good!

Another small/medium suggestion: Since you're adding a new interface
for non-core users of timekeeping_suspended, it might be good to
switch the other users as well (seems like just
drivers/clk/ti/clkctrl.c and kernel/sched/clock.c), then also remove
the extern in include/linux/timekeeping.h (so there's one consistent
method to access it)? I know it's a sort of scope creep, so apologies
for asking, but it would make the series more attractive if it's not
leaving something for others to clean up later.

thanks
-john