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    SubjectRe: [PATCH] mm: avoid livelock on !__GFP_FS allocations
    On Tue, 25 Oct 2011, Colin Cross wrote:

    > GFP_KERNEL is __GFP_WAIT | __GFP_IO | __GFP_FS. Once driver suspend
    > has started, gfp_allowed_mask is ~(__GFP_IO | GFP_FS), so any call to
    > __alloc_pages_nodemask(GFP_KERNEL, ...) gets masked to effectively
    > __alloc_pages_nodemask(__GFP_WAIT, ...).

    Just passing __GFP_WAIT is the problem that you're trying to address,
    though. Why not include __GFP_NORETRY since you know the liklihood of
    allocation being successful on the second iteration is very slim since
    you're not in a context where you can force reclaim or oom killing?

    > The loop is in __alloc_pages_slowpath, from the rebalance label to
    > should_alloc_retry.

    The loop is by design and is activated because you're just passing
    __GFP_WAIT in this context for no sensible reason.

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      Last update: 2011-10-26 00:15    [W:0.020 / U:134.148 seconds]
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