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    SubjectRe: [PATCH 03/18] tty: Simplify tty buffer/ldisc interface with helper function
    >> I have little question about flush_to_ldisc().
    >> Does can it be multithreaded?
    >>
    >> I think yes, because on SMP schedule_work() can work on different CPU paralleled.
    >
    > Yes, the same work item can now run in parallel on SMP since Tejun Heo
    > re-did the workqueue implementation on 2.6.36 [Stefan Richter, the
    > firewire maintainer, recently explained this history to me].

    About multi threaded delayed works:

    In many cases tty layer needs single threaded delayed work for each tty instance.
    I propose discussion about create for this purpose (tty layer)'s workqueue with WQ_NON_REENTRANT flag.
    And use it instead common schedule_work()'s workqueue - system_wq.
    I don't know how expensive(for system resource and CPU) it can be,
    but for tty layer, it can be very useful.

    >
    >> What do you think about this race condition?
    >> https://lkml.org/lkml/2011/11/7/98
    >
    > Yes, that is a possible race condition that could lead to some nasty
    > results. Good find.
    >
    > If you want, I could bring that patch into this patchset or you could
    > re-submit that patch to Greg and I could rebase this patchset on top of
    > that.

    Peter,
    Please, do it anywhere you consider possible,
    I can't do it myself now.

    Thank you,
    Ilya.



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