Re: [PATCH] percpu ida: Switch to cpumask_t, add some comments

[Kent Overstreet <kmo@daterainc.com>]

On Wed, Aug 28, 2013 at 01:25:50PM -0700, Andrew Morton wrote:
> On Wed, 28 Aug 2013 12:55:17 -0700 Kent Overstreet <kmo@daterainc.com> wrote:
> 
> > Fixup patch, addressing Andrew's review feedback:
> 
> Looks reasonable.
> 
> >  lib/idr.c           | 38 +++++++++++++++++++++-----------------
> 
> I still don't think it should be in this file.
> 
> You say that some as-yet-unmerged patches will tie the new code into
> the old ida code.  But will it do it in a manner which requires that
> the two reside in the same file?

Not require, no - but it's just intimate enough with my ida rewrite that
I think it makes sense; it makes some use of stuff that should be
internal to the ida code.

Mostly just sharing the lock though, since I got rid of the ida
interfaces that don't do locking, but percpu ida needs a lock that also
covers what ida needs.

It also makes use of a ganged allocation interface, but there's no real
reason ida can't expose that, it's just unlikely to be useful to
anything but percpu ida.

The other reason I think it makes sense to live in idr.c is more for
users of the code; as you pointed out as far as the user's perspective
percpu ida isn't doing anything fundamentally different from ida, so I
think it makes sense for the code to live in the same place as a
kindness to future kernel developers who are trying to find their way
around the various library code.