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Date: Sun, 21 May 2017 19:57:53 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Christoph Hellwig <hch@lst.de>
cc: Arnd Bergmann <arnd@arndb.de>, Mark Gross <mark.gross@intel.com>,
        Tejun Heo <tj@kernel.org>,
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        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/9] timers: provide a "modern" variant of timers
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References: <20170516114812.10660-1-hch@lst.de> <20170516114812.10660-3-hch@lst.de> <CAK8P3a106wR4h_muGGF7S7uh5UrH-OcJObMfVgk22P9brP5Bjg@mail.gmail.com> <20170518082448.GB3812@lst.de> <20170518084136.GA5331@lst.de>
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On Thu, 18 May 2017, Christoph Hellwig wrote:
> On Thu, May 18, 2017 at 10:24:48AM +0200, Christoph Hellwig wrote:
> > > b) give the union a name (breaks any reference to timer_list->func in C code):
> > > 
> > >  +       union {
> > >  +               void            (*func)(struct timer_list *timer);
> > >  +               void            (*function)(unsigned long);
> > >  +       } u;
> > 
> > I'll look into that, as it seems a lot safer, and places outside
> > the timer code shouldn't really touch it (although I bet they do,
> > so more fixes for this series..)
> 
> Meh.  All the old init_timer users set function directly, so
> I guess we need to use the other approach.

There is another possibility. Create a coccinelle script which wraps all

      timer.function = f;
      timer->function = f;

assignements into a helper timer_set_function(timer, func) and ask Linus to
run it right before the next -rc. That handles everything in tree and the
few new instances in next can be addressed with patches sent to the
maintainers.

Thanks,

	tglx