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    SubjectRe: Next round: revised futex(2) man page for review
    On Tue, Jul 28, 2015 at 10:23:51PM +0200, Thomas Gleixner wrote:

    > > FUTEX_WAKE (since Linux 2.6.0)
    > > This operation wakes at most val of the waiters that are
    > > waiting (e.g., inside FUTEX_WAIT) on the futex word at the
    > > address uaddr. Most commonly, val is specified as either
    > > 1 (wake up a single waiter) or INT_MAX (wake up all wait‐
    > > ers). No guarantee is provided about which waiters are
    > > awoken (e.g., a waiter with a higher scheduling priority
    > > is not guaranteed to be awoken in preference to a waiter
    > > with a lower priority).
    >
    > That's only correct up to Linux 2.6.21.
    >
    > Since 2.6.22 we have a priority ordered wakeup. For SCHED_OTHER
    > threads this takes the nice level into account. Threads with the same
    > priority are woken in FIFO order.

    Maybe don't mention the effects of SCHED_OTHER, order by nice value is
    'wrong'.

    Also, this code seems to use plist, which means it won't do the right
    thing for SCHED_DEADLINE either.

    Do we want to go fix that?


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