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SubjectRe: [patch 3/4] mm: bootmem: drop superfluous range check when freeing pages in bulk
Hello Johannes,

On Tue, Dec 13, 2011 at 02:58:30PM +0100, Johannes Weiner wrote:
> The area node_bootmem_map represents is aligned to BITS_PER_LONG, and
> all bits in any aligned word of that map valid. When the represented
> area extends beyond the end of the node, the non-existant pages will
> be marked as reserved.
>
> As a result, when freeing a page block, doing an explicit range check
> for whether that block is within the node's range is redundant as the
> bitmap is consulted anyway to see whether all pages in the block are
> unreserved.
>
> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
I suggest to drop my patch then and add something like

Reported-by: $me

to this one instead.

Other than that I will give your series a spin on my ARM machine later
today.

Best regards
Uwe

> ---
> mm/bootmem.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/mm/bootmem.c b/mm/bootmem.c
> index 3e6f152..1aea171 100644
> --- a/mm/bootmem.c
> +++ b/mm/bootmem.c
> @@ -197,7 +197,7 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
> idx = start - bdata->node_min_pfn;
> vec = ~map[idx / BITS_PER_LONG];
>
> - if (aligned && vec == ~0UL && start + BITS_PER_LONG <= end) {
> + if (aligned && vec == ~0UL) {
> int order = ilog2(BITS_PER_LONG);
>
> __free_pages_bootmem(pfn_to_page(start), order);
> --
> 1.7.7.3
>
>

--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | http://www.pengutronix.de/ |
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