Re: [PATCH 5/5] random: Defer processing of randomness on PREEMPT_RT.

[Herbert Xu]

Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> wrote:
>
> Even the IOCTL path must spin with disabled interrupts to avoid dead
> locks. Therefore it makes no sense if attempt acquire the lock from
> process or IRQ context. Something like
>        while (!raw_spin_trylock_irqsave())
>                cpu_relax()

What about the TCP socket locking model?

IOW, the user-space slow path will add itself to a backlog queue
during contention, and the interrupt fast path will schedule work
to process any user-space backlog on exit.

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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