Re: [PATCH 1/3] Add missing page rounding of a page_entry

[Richard Guenther <richard.guenther@gmail.com>]

On Fri, Oct 21, 2011 at 7:52 AM, Andi Kleen <andi@firstfloor.org> wrote:
> From: Andi Kleen <ak@linux.intel.com>
>
> This one place in ggc forgot to round page_entry->bytes to the
> next page boundary, which lead to all the heuristics in freeing to
> check for continuous memory failing. Round here too, like all other
> allocators already do. The memory consumed should be the same
> for MMAP because the kernel would round anyways. It may slightly
> increase memory usage when malloc groups are used.
>
> This will also increase the hitrate on the free page list
> slightly.

Ok.

Thanks,
RIchard.

> gcc/:
>
> 2011-10-18  Andi Kleen  <ak@linux.intel.com>
>
>        * ggc-page.c (alloc_pages): Always round up entry_size.
> ---
>  gcc/ggc-page.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/gcc/ggc-page.c b/gcc/ggc-page.c
> index 2da99db..ba88e3f 100644
> --- a/gcc/ggc-page.c
> +++ b/gcc/ggc-page.c
> @@ -736,6 +736,7 @@ alloc_page (unsigned order)
>   entry_size = num_objects * OBJECT_SIZE (order);
>   if (entry_size < G.pagesize)
>     entry_size = G.pagesize;
> +  entry_size = ROUND_UP (entry_size, G.pagesize);
>
>   entry = NULL;
>   page = NULL;
> --
> 1.7.5.4
>
>