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    SubjectRe: [PATCH] Use tty_schedule in VT code.

    > James Simmons wrote:
    > > Because sometimes you do want the delay. In other parts of the tty code we
    > > do delay. What should be done is
    >
    > Correct, so we must stick with the delayed work structure
    > which requires calling the delayed work function.
    >
    > > if (tty->low_latency)
    > > flush_to_ldisc(&tty->buf.work.work);
    > > else
    > > schedule_delayed_work(&tty->buf.work, 1);
    > >
    > > Is this acceptable to you?
    >
    > That does not make sense to me.
    >
    > If you are calling from interrupt context, you do not want
    > to call flush_to_ldisc() directly regardless of low_latency.
    > This used to be the way it was done and it ended up causing
    > deadlocks in just that situation.

    The low_latency is used by the drivers in the case where its
    not in a interrupt context. Well we are trusting the drivers.
    Now if it is true what you said then tty_flip_buffer_push has
    a bug. Looking at several drivers including serial devices
    they set the low_latency flag.

    > And the initial schedule has no reason to add the extra delay.

    So do you support a non delay work queue as well?


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