Re: [PATCH 0/2] crypto: add new driver for Marvell CESA

Herbert Xu
2015-04-29T09:49:02Z

On Tue, Apr 28, 2015 at 09:52:32PM +0200, Boris Brezillon wrote:
>
> In particular, I'd like to discuss the threaded-irq approach taken in
> this driver (other drivers are using tasklets).
> The main reason behind this choice is the fact that crypto engines
> are quite fast, and I'm worried about the CPU contention that might
> happen in case of fully loaded crypto engines (the CPU might spend most
> of its time in interrupt context until the crypto queue is emptied).
> Using threaded-irq allows preemption of the crypto completion
> operation, thus authorizing another thread (with higher priority) to be
> scheduled. ITOH, the tasklet approach provide slightly performances (I
> don't recall the exact numbers, but Arnaud did some tests).

Either approach is fine with me.

Cheers,
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
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