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    SubjectDo not deprecate binary semaphore or do allow mutex in software interrupt contexts
    Peter Zijlstra <>:
    > Yes it is.

    Why do you think it is broken?

    > If you have to wait a long time in an atomic context you've done
    > something wrong.

    I saw an implementation where there were two atomic contexts, one to initiate reading and another to complete the reading.
    That way, there was no busy wait for a long time in an atomic context.

    > If you're only reading it from an atomic context you
    > might consider storing a copy that can be quickly updated and protect
    > that using a spinlock.

    You suggested that a user-space task read from the device.
    But that includes more context switching and therefore consumes more resources than reading just from an atomic context.

    > Not being too familiar with the timer stuff, it smells wrong what you
    > say.


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