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    SubjectRe: BogoMIPS
    Hi!

    > > > > As a result, 2.0.x just does it as a separate subroutine in
    > > > >
    > > > > arch/i386/lib/delay.S
    > > > >
    > > > > and that pretty much forces it to not jitter at all. If you'd send me that
    > > > > kind of patch I'd accept it.
    > >
    > > It jitters on cyrix unless you force alignments too. I've not figured out
    > > the logic that can cause this just that it happens.
    > >
    > > > I think the right thing is to use the TSC if the machine has one
    > > > (which can be trusted.) That leaves only older, simple machines to
    > > > use timing loops.
    > >
    > > That needs the time.c patches to 2.1.x otherwise you cant use non intel
    > > chips TSC or use the TSC on an APM aware kernel
    >
    > This works and gets rid of the two jmps that everybody complained
    > about.

    Are you sure? I saw reports where it depended on place in _page_
    (imagine udelay loop at page boundary). So you maybe should .align
    PAGE_SIZE.

    > - "1:\tdecl %0\n\tjns 1b"
    > + "\tpushl %%cs\n"
    > + "\tpushl $doit\n"
    > + "\tlret\n"
    > + ".align 16\n"
    > + "doit:\tdecl %%eax\n\tjns doit"
    > :/* no outputs */
    > :"a" (loops)
    > :"ax");

    --
    I'm really pavel@atrey.karlin.mff.cuni.cz. Pavel
    Look at http://atrey.karlin.mff.cuni.cz/~pavel/ ;-).

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