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    SubjectRe: 2.6.18-rc6-mm1: GPF loop on early boot
    Ingo Molnar wrote:
    > another thing about i386-pda: why did you pick the %gs selector to store
    > the PDA in? %fs would be a better choice because %gs is used by glibc so
    > the saving/restoring of %fs would likely be near zero-cycles cost.
    > (instead of the current 9 cycles for saving/restoring %gs)
    >

    Why would saving/restoring %fs be quicker? The main reason I chose %gs
    was so that it didn't add anything to the context switch time (since %gs
    needed to be switched anyway), and it leaves open the possibility of
    using gcc's TLS support in the kernel (I have a working demonstration of
    this, but Rusty and I are still working out the module details).

    J
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