Re: [PATCH v1 06/10] clocksource: Remove "weak" from clocksource_default_clock() declaration

From: Martin Schwidefsky <schwidefsky@de.ibm.com>
To: Bjorn Helgaas <bhelgaas@google.com>
Cc: Jason Wessel <jason.wessel@windriver.com>,
	Ralf Baechle <ralf@linux-mips.org>,
	Ingo Molnar <mingo@redhat.com>,
	John Stultz <john.stultz@linaro.org>,
	Eric Paris <eparis@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Andrew Morton <akpm@linux-foundation.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Daniel Lezcano <daniel.lezcano@linaro.org>,
	"linux-s390@vger.kernel.org" <linux-s390@vger.kernel.org>
Subject: Re: [PATCH v1 06/10] clocksource: Remove "weak" from clocksource_default_clock() declaration
Date: Thu, 16 Oct 2014 09:22:32 +0200	[thread overview]
Message-ID: <20141016092232.570be048@mschwide> (raw)
In-Reply-To: <CAErSpo5E6zxtogVjMqZiUGAoRz6mMudSUqcH9B+DZ-R8xYN2kQ@mail.gmail.com>

On Wed, 15 Oct 2014 17:30:33 -0600
Bjorn Helgaas <bhelgaas@google.com> wrote:

> [+cc Daniel, Martin, linux-s390; sorry, I botched my "stg mail" so you
> weren't included the first time.  s390 could see issues from this.]
> 
> On Wed, Oct 15, 2014 at 11:06 AM, Bjorn Helgaas <bhelgaas@google.com> wrote:
> > kernel/time/jiffies.c provides a default clocksource_default_clock()
> > definition explicitly marked "weak".  arch/s390 provides its own definition
> > intended to override the default, but the "weak" attribute on the
> > declaration applied to the s390 definition as well, so the linker chose one
> > based on link order (see 10629d711ed7 ("PCI: Remove __weak annotation from
> > pcibios_get_phb_of_node decl")).
> >
> > Remove the "weak" attribute from the clocksource_default_clock()
> > declaration so we always prefer a non-weak definition over the weak one,
> > independent of link order.
> >
> > Fixes: f1b82746c1e9 ("clocksource: Cleanup clocksource selection")
> > Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
> > CC: Daniel Lezcano <daniel.lezcano@linaro.org>
> > CC: Martin Schwidefsky <schwidefsky@de.ibm.com>
> > ---
> >  include/linux/clocksource.h |    2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
> > index 653f0e2b6ca9..abcafaa20b86 100644
> > --- a/include/linux/clocksource.h
> > +++ b/include/linux/clocksource.h
> > @@ -287,7 +287,7 @@ extern struct clocksource* clocksource_get_next(void);
> >  extern void clocksource_change_rating(struct clocksource *cs, int rating);
> >  extern void clocksource_suspend(void);
> >  extern void clocksource_resume(void);
> > -extern struct clocksource * __init __weak clocksource_default_clock(void);
> > +extern struct clocksource * __init clocksource_default_clock(void);
> >  extern void clocksource_mark_unstable(struct clocksource *cs);
> >
> >  extern u64
> >

s390 compiles and boots without the __weak for clocksource_default_clock.

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.