Re: [PATCH] RDMA/mlx4: Use bitmap_alloc() when applicable

[Christophe JAILLET]

Le 25/11/2021 à 20:58, Joe Perches a écrit :
> On Thu, 2021-11-25 at 20:42 +0100, Christophe JAILLET wrote:
> > Use 'bitmap_alloc()' to simplify code, improve the semantic and avoid some
> > open-coded arithmetic in allocator arguments.
> >
> > Also change the corresponding 'kfree()' into 'bitmap_free()' to keep
> > consistency.
>
> Thanks.
>
> > diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
> []
> > @@ -2784,10 +2784,8 @@ static void *mlx4_ib_add(struct mlx4_dev *dev)
> >   		if (err)
> >   			goto err_counter;
> >   
> > -		ibdev->ib_uc_qpns_bitmap =
> > -			kmalloc_array(BITS_TO_LONGS(ibdev->steer_qpn_count),
> > -				      sizeof(long),
> > -				      GFP_KERNEL);
> > +		ibdev->ib_uc_qpns_bitmap = bitmap_alloc(ibdev->steer_qpn_count,
> > +							GFP_KERNEL);
>
> I wonder if it'd be simpler/smaller to change this to bitmap_zalloc and
> remove the bitmap_zero in the if below.

I asked myself the same question.
It is easy to see that the bitmap is either cleared or set.
So this is fine enough for me.

Let see if a maintainer has a preference on it.

CJ