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    SubjectRe: module changes
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    In message <15954.22427.557293.353363@gargle.gargle.HOWL> you write:
    > Rusty Russell writes:
    > > D: This adds percpu support for modules. A module cannot have more
    > > D: percpu data than the base kernel does (on my kernel 5636 bytes).
    >
    > This limitation is quite horrible.
    >
    > Does the implementation have to be perfect? The per_cpu API can easily
    > be simulated using good old NR_CPUS arrays:

    The problem is that then you have to have to know whether this is a
    per-cpu thing created in a module, or not, when you use it 8(

    There are two things we can use to alleviate the problem. The first
    would be to put a minimal cap on the per-cpu data size (eg. 8k). The
    other possibility is to allocate on an object granularity, in which
    case the rule becomes "no single per-cpu object can be larger than
    XXX", but the cost is to write a mini allocator.

    I agree with you (and John) about disliking the limitation, but is it
    worse than the current no per-cpu stuff in modules at all?

    Thanks!
    Rusty.
    --
    Anyone who quotes me in their sig is an idiot. -- Rusty Russell.
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