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    SubjectRe: CONFIG_PREEMPT and server workloads
    On Thu, Mar 18, 2004 at 12:48:50PM -0500, Robert Love wrote:
    > On Thu, 2004-03-18 at 09:51, Andrea Arcangeli wrote:
    >
    > > the counter is definitely not optimized away, see:
    >
    > This is because of work Dave Miller and Ingo did - irq count, softirq
    > count, and lock count (when PREEMPT=y) are unified into preempt_count.
    >
    > So it is intended.
    >
    > The unification makes things cleaner and simpler, using one value in
    > place of three and one interface and concept in place of many others.
    > It also gives us a single simple thing to check for an overall notion of
    > "atomicity", which is what makes debugging so nice.

    You're right, I didn't notice the other counters disappeared. Those
    counter existed anyways w/o preempt too, so it would been superflous
    with preempt=y to do the accounting in two places. So this is zerocost
    with preempt=n and I was wrong claiming superflous preempt leftovers.
    -
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