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

From: Will McVicker <willmcvicker@google.com>
To: John Stultz <john.stultz@linaro.org>
Cc: Russell King <linux@armlinux.org.uk>,
	Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	Michael Turquette <mturquette@baylibre.com>,
	Stephen Boyd <sboyd@kernel.org>,
	Sylwester Nawrocki <s.nawrocki@samsung.com>,
	Tomasz Figa <tomasz.figa@gmail.com>,
	Chanwoo Choi <cw00.choi@samsung.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	Alessandro Zummo <a.zummo@towertech.it>,
	Alexandre Belloni <alexandre.belloni@bootlin.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Lee Jones <lee.jones@linaro.org>,
	Geert Uytterhoeven <geert@linux-m68k.org>,
	Saravana Kannan <saravanak@google.com>,
	Android Kernel Team <kernel-team@android.com>,
	linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
	lkml <linux-kernel@vger.kernel.org>,
	Linux Samsung SOC <linux-samsung-soc@vger.kernel.org>,
	"open list:COMMON CLK FRAMEWORK" <linux-clk@vger.kernel.org>,
	"open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
	linux-rtc@vger.kernel.org
Subject: Re: [PATCH v2 02/12] timekeeping: add API for getting timekeeping_suspended
Date: Thu, 30 Sep 2021 11:31:23 -0700	[thread overview]
Message-ID: <CABYd82YVpP=OGmehwEkc_Q-JBiNy3ZN3LFkEKwv2s4RQn20YZw@mail.gmail.com> (raw)
In-Reply-To: <CALAqxLXUOY+tdJat0YaxAEiS_AWrwxBaLq3M90btSVdWfvFBag@mail.gmail.com>

Thanks for the suggestion. That makes sense. I'll look into that for
the next version.

--Will

On Wed, Sep 29, 2021 at 1:46 PM John Stultz <john.stultz@linaro.org> wrote:
>
> On Wed, Sep 29, 2021 at 1:01 PM Will McVicker <willmcvicker@google.com> wrote:
> > On Tue, Sep 28, 2021 at 8:42 PM John Stultz <john.stultz@linaro.org> wrote:
> > > On Tue, Sep 28, 2021 at 4:56 PM Will McVicker <willmcvicker@google.com> 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