Re: [PATCH] padata: Replace delayed timer with immediate workqueue in padata_reorder

[Daniel Jordan]

On Thu, Jul 18, 2019 at 10:56:34PM +0800, Herbert Xu wrote:
> On Thu, Jul 18, 2019 at 10:27:30AM -0400, Daniel Jordan wrote:
> >
> > That's what I expected when I first saw it too, but nr_cpumask_bits is returned
> > to signal the end of the iteration.  The patch always passes 0 for the 'start'
> > argument, so when cpumask_next_wrap is called with the last cpu in the mask,
> > the end-of-iteration case is triggered.  To reassure you and myself :) I ran it
> > and got the expected crash.
> > 
> > Passing pd->cpu for the start argument instead avoids that problem, but the
> > one-cpu-in-mask case still needs handling because cpumask_next_wrap always
> > signals end of iteration for that, hence the cpumask_weight check.
> 
> My bad.  I should have set start to -1 to make it do the right thing.

Oh, you're right, that's nicer, just noticed other callers do it that way as
well.