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Subject: Re: [PATCH V3 6/6] crypto/nx: Add P9 NX support for 842 compression
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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Haren Myneni <haren@linux.vnet.ibm.com>
Cc: Dan Streetman <ddstreet@ieee.org>, Michael Ellerman <mpe@ellerman.id.au>,
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Date: Wed, 30 Aug 2017 07:57:17 +1000
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On Tue, 2017-08-29 at 14:54 -0700, Haren Myneni wrote:
> Opening send window for each crypto transform (crypto_alloc,
> compression/decompression, ..., crypto_free) so that does not have to
> wait for the previous copy/paste complete. VAS will map send and
> receive windows, and can cache in send windows (up to 128). So I
> thought using the same send window (per chip) for more requests (say
> 1000) may be adding overhead.
> 
> I will make changes if you prefer using 1 send window per chip.  

Did you check the cost of opening/closing a window ?

Cheers,
Ben.