Re: tick-common.c hack for s390 needed

[Heiko Carstens <heiko.carstens@de.ibm.com>]

On Tue, Mar 25, 2008 at 08:09:15PM +0100, Thomas Gleixner wrote:
> On Sun, 23 Mar 2008, Russell King wrote:
> 
> > On Sat, Mar 22, 2008 at 09:32:23PM +0100, Heiko Carstens wrote:
> > > Generic code is not supposed to include irq.h. Replace this include
> > > by linux/hardirq.h instead and add/replace an include of linux/irq.h
> > > in asm header files where necessary.
> > > This change should only matter for architectures that make use of
> > > GENERIC_CLOCKEVENTS.
> > > Architectures in question are mips, x86, arm, sh, powerpc, uml and sparc64.
> > > 
> > > I did some cross compile tests for mips, x86_64, arm, powerpc and sparc64.
> > > This patch fixes also build breakages caused by the include replacement in
> > > tick-common.h.
> > 
> > I generally dislike adding optional linux/* includes in asm/* includes -
> > I'm nervous about this causing include loops.
> > 
> > However, there's a separate point to be discussed here.
> > 
> > That is, what interfaces are expected of every architecture in the kernel.
> > If generic code wants to be able to set the affinity of interrupts, then
> > that needs to become part of the interfaces listed in linux/interrupt.h
> > rather than linux/irq.h.
> > 
> > So what I suggest is this approach instead (against Linus' tree of a
> > couple of days ago) - we move irq_set_affinity() and irq_can_set_affinity()
> > to linux/interrupt.h, change the linux/irq.h includes to linux/interrupt.h
> > and include asm/irq_regs.h where needed (asm/irq_regs.h is supposed to be
> > rarely used include since not much touches the stacked parent context
> > registers.)
> 
> That patch makes a lot of sense and resolves all the issues. 
> 
> I push it through hrt.git and add the GENERIC_HARDIRQS dependency
> which was requested by Heiko.

Thomas, would you mind if we push this patch via git-s390?
As far as I can see s390 is the only architecture which has a dependency on
this patch. This would make merging our NO_IDLE_HZ to GENERIC_CLOCKEVENTS
conversion easier.
I'd take the version you have in your mm branch in your hrt tree, if you're
ok with this.