Re: [PATCH] lib: Replace calls to __get_free_pages() with __get_dma_pages().

["rae l" <crquan@gmail.com>]

On 6/6/07, Andrew Morton <akpm@linux-foundation.org> wrote:
> On Tue, 5 Jun 2007 16:58:57 -0400 (EDT)
> "Robert P. J. Day" <rpjday@mindspring.com> wrote:
>
> > Replace a couple calls to __get_free_pages() with the corresponding
> > calls to __get_dma_pages().
> >
> > Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
> >
> > ---
> >
> >   that's the lot of them.
> >
> > diff --git a/lib/swiotlb.c b/lib/swiotlb.c
> > index 10c13ad..8fc38dc 100644
> > --- a/lib/swiotlb.c
> > +++ b/lib/swiotlb.c
> > @@ -201,8 +201,7 @@ swiotlb_late_init_with_default_size(size_t default_size)
> >       bytes = io_tlb_nslabs << IO_TLB_SHIFT;
> >
> >       while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) {
> > -             io_tlb_start = (char *)__get_free_pages(GFP_DMA | __GFP_NOWARN,
> > -                                                     order);
> > +             io_tlb_start = (char *)__get_dma_pages(__GFP_NOWARN, order);
>
> __get_dma_pages() is just pointless obfuscation.  I think it'd be better to
> go the other way: open-code the GFP_DMA at all callsites then send
> __get_dma_pages() bitbucketwards.
thus __get_free_pages(GFP_DMA ...) can do better, I don't think
__get_dma_pages is needed.

-- 
Denis Cheng
Linux Application Developer