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    SubjectRe: [PATCH] syscall latency improvement #1
    Alan Cox wrote:
    > > NOTE! There are potentially other ways to do all of this, _without_ losing
    > > atomicity. For example, you can move the "flags" value into the slot saved
    > > for the CS segment (which, modulo vm86, will always be at a constant
    > > offset on the stack), and make CS=0 be the work flag. That will cause the
    > > CPU to trap atomically at the "iret".
    >
    > Is the test even needed. Suppose we instead patch the return stack if we
    > set need_resched/sigpending, and do it on the rare occassion we set the
    > value.

    Yes, that's what you'll find in one of Ingo Molnar's low latency patches.

    -- Jamie
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