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    SubjectRe: [GIT RFC] percpu: use dynamic percpu allocator as the default percpu allocator
    Hello, Martin.

    Sorry about the delay.

    Martin Schwidefsky wrote:
    > We do have a problem with #2, the dynamic percpu patches currently
    > breaks s390. But the nice thing is that we can now get rid of the GOTENT
    > relocation for the percpu symbols. If the code is changed to use
    > RELOC_HIDE for the SHIFT_PERCPU_PTR define, everything works just fine.
    > Patch attached. Nice works guys.
    >
    > Subject: [PATCH] s390: percpu access.
    >
    > From: Martin Schwidefsky <schwidefsky@de.ibm.com>
    >
    > With the dynamic percpu allocator there is no need anymore to play
    > tricks with the GOTENT relocation for the access to the percpu
    > symbols. A simple RELOC_HIDE gets the job done.

    Hmm... I don't quite get it. The GOTENT was to work around large
    offsets for modules, right? Can you please explain what changed by
    the dynamic percpu allocator?

    > +#define SHIFT_PERCPU_PTR(var, offset) RELOC_HIDE(&per_cpu_var(var), (offset))

    Hmm... @var already has per_cpu__ prefix when the above macro is
    invoked, so doing per_cpu_var() on it again wouldn't work. If simple
    RELOC_HIDE works, you should be able to simply drop the above
    definition. The generic percpu.h will define it.

    Thanks.

    --
    tejun


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