Subject: Re: [PATCH V3 6/6] crypto/nx: Add P9 NX support for 842 compression engine

From: Haren Myneni <[email-masked]>
Date: Tue, 29 Aug 2017 18:02:09 -0700

On 08/29/2017 02:57 PM, Benjamin Herrenschmidt wrote:
> 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 ?

No, Not yet. opening / closing happens only during alloc/free, but not for each compression/decompression. Hence used separate send windows. 

Thanks
Haren  
 
> Cheers,
> Ben.