Re: [PATCH]x86, reboot: Fix a warning message triggered bystop_other_cpus()

[Feng Tang]

On Wed, 30 May 2012 10:51:10 +0200
Ingo Molnar <mingo@xxxxxxxxxx> wrote:

> 
> * Feng Tang <feng.tang@xxxxxxxxx> wrote:
> 
> > Hi Don,
> > 
> > On Tue, 22 May 2012 09:33:56 -0400
> > Don Zickus <dzickus@xxxxxxxxxx> wrote:
> > 
> > > On Tue, May 22, 2012 at 10:52:33AM +0800, Feng Tang wrote:
> > > > 
> > > > The root cause seems to be the default_send_IPI_mask_allbutself_phys()
> > > > takes quiet some time (I measured it could be several ms) to complete
> > > > sending NMIs to all the other 23 CPUs, and for HZ=250/1000 system, the
> > > 
> > > I sent Ingo a patch (which he took in), that reverts this path to
> > > interrupts again (and NMIs as a fallback if it fails).  The problem will
> > > still exist I assume though I don't know if it changes the timing
> > > characteristics.
> > 
> > Thanks for your review and letting me know the revert which I just saw in
> > the latest Linus' tree. And I think this new mechanism will greatly reduce
> > the possibility, but it still exist as the old nmi_stop_other_cpus's
> > implementation still exist. So
> > 
> > Ingo,
> > 
> > Could you review this patch? thanks,
> 
> It doesn't apply anymore, so please merge and add Don's 
> Acked-by.

Hi Ingo,

Following is the updated patch, which could be applied to Linus's tree
and tip tree's master branch.

Thanks,
Feng
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