Re: Real-Time Preemption and RCU

[Herbert Xu]

Ingo Molnar <mingo@xxxxxxx> wrote:
>
> i really have no intention to allow multiple readers for rt-mutexes. We
> got away with that so far, and i'd like to keep it so. Imagine 100
> threads all blocked in the same critical section (holding the read-lock)
> when a highprio writer thread comes around: instant 100x latency to let
> all of them roll forward. The only sane solution is to not allow
> excessive concurrency. (That limits SMP scalability, but there's no
> other choice i can see.)

What about allowing only as many concurrent readers as there are CPUs?
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