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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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