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    SubjectRe: [PATCH] alternate Posix timer patch
    mbs wrote:
    >
    > the way I handled this was that the timerid was the (kernel space) address of
    > the dynamically allocated timer structure. this provides a fairly low
    > likelyhood of duplicate timerid's value....

    Yes, but this is a VERY messy pointer which must be verified
    to not cause a kernel fault before it can even be
    dereferenced... nuff said.

    -g

    by the way, the address mbs@mc.com fails. Maybe you could
    use something I can mail to.
    >
    > On Wednesday 23 October 2002 15:48, Jim Houston wrote:
    > > george anzinger wrote:
    > > > Jim Houston wrote:
    > > > I have also looked at the timer index stuff and made a few
    > > > changes. If it get it working today, I will include it
    > > > also. My changes mostly revolved around not caring about
    > > > reusing a timer id. Would you care to comment on why you
    > > > think reuse is bad?
    > > >
    > > > With out this feature the code is much simpler and does not
    > > > keep around dead trees.
    > > >
    > > > -g
    > >
    > > Hi George,
    > >
    > > I assume the rationale is that not reusing the same id immediately helps
    > > catch errors in user code. Since the id space is global, there
    > > is more chance that one process may be manipulating another processes
    > > timer. Reusing the same id makes this sort of problem harder to
    > > catch.
    > >
    > > The main reason I changed this in my patch is to avoid the CONFIG
    > > limit on the number of timers. Since I don't have the fixed array,
    > > I need a way to safely translate a user-space id into a kernel pointer.
    > >
    > > Jim Houston Concurrent Computer Corp.
    > > -
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    >
    > --
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    --
    George Anzinger george@mvista.com
    High-res-timers:
    http://sourceforge.net/projects/high-res-timers/
    Preemption patch:
    http://www.kernel.org/pub/linux/kernel/people/rml
    -
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