Re: [PATCH v1 1/3] bitmap: Add bitmap_alloc(), bitmap_zalloc() and bitmap_free()

Dmitry Torokhov
2018-06-04T21:57:29Z

On Mon, Jun 04, 2018 at 12:59:54PM +0300, Andy Shevchenko wrote:
> On Fri, 2018-06-01 at 11:33 -0700, Dmitry Torokhov wrote:
> > Hi Andy,
> >
> > On Fri, Jun 01, 2018 at 11:31:18AM +0300, Andy Shevchenko wrote:
> > > A lot of code become ugly because of open coding allocations for
> > > bitmaps.
> > >
> > > Introduce three helpers to allow users be more clear of intention
> > > and keep their code neat.
> > >
> > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> >
> > This looks nice and I like how it simplifies drivers.
>
> Thanks!
>
> > How do we merge
> > this?
>
> I suppose through 'input' tree if there is no objections.

OK, let's wait for objections for a few days.

>
> > > ---
> > > include/linux/bitmap.h | 16 ++++++++++++++++
> > > 1 file changed, 16 insertions(+)
> > >
> > > diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
> > > index 1ee46f492267..845822425393 100644
> > > --- a/include/linux/bitmap.h
> > > +++ b/include/linux/bitmap.h
> > > @@ -6,6 +6,7 @@
> > >
> > > #include <linux/types.h>
> > > #include <linux/bitops.h>
> > > +#include <linux/slab.h>
> > > #include <linux/string.h>
> > > #include <linux/kernel.h>
> > >
> > > @@ -104,6 +105,21 @@
> > > * contain all bit positions from 0 to 'bits' - 1.
> > > */
> > >
> > > +static inline unsigned long *bitmap_alloc(unsigned int nbits, gfp_t
> > > flags)
> > > +{
> > > + return kmalloc_array(BITS_TO_LONGS(nbits), sizeof(unsigned
> > > long), flags);
> > > +}
> > > +
> > > +static inline unsigned long *bitmap_zalloc(unsigned int nbits,
> > > gfp_t flags)
> > > +{
> > > + return kcalloc(BITS_TO_LONGS(nbits), sizeof(unsigned long),
> > > flags);
> >
> > retrun bitmap_alloc(nbits, flags | __GFP_ZERO);
> >
> > ?
>
> I though about this, but decide not to rely on linux/gfp.h.
> If you think explicit __GFP_ZERO is better, I can replace in v2, or if

I like it ;) and we already do it for kcalloc done via kmalloc_array
with __GFP_ZERO or kzalloc (kmalloc with __GFP_ZERO).

> you have a chance to do that when applying it would be appreciated.

Yeah, I can do that, no problem.

Thanks.

--
Dmitry