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    SubjectRe: [PATCH] 2.6.5-aa1 arch updates
    Andrew Morton <akpm@osdl.org> wrote:
    >
    > Hugh Dickins <hugh@veritas.com> wrote:
    > >
    > > I notice that's a __GFP_REPEAT allocation, but even those fail when
    > > OOM-killed - I find its alias __GFP_NOFAIL very misleading.
    >
    > #define __GFP_REPEAT 0x400 /* Retry the allocation. Might fail */
    > #define __GFP_NOFAIL 0x800 /* Retry for ever. Cannot fail */
    >
    > __GFP_REPEAT is mainly for higher-order allocations which would otherwise
    > have given up too early.

    It all comes back to me now. The reason there is a __GFP_REPEAT in the
    pte_alloc_one() implementations is that lots of architectures used to do
    stuff like this:

    static inline pte_t *
    pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
    {
    int count = 0;
    pte_t *pte;

    do {
    pte = (pte_t *)__get_free_page(GFP_KERNEL);
    if (pte)
    clear_page(pte);
    else {
    current->state = TASK_UNINTERRUPTIBLE;
    schedule_timeout(HZ);
    }
    } while (!pte && (count++ < 10));

    return pte;
    }

    That was all removed and the __GFP_REPEAT flag was added instead, as a "try
    really hard" hint to the page allocator.

    -
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