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From: Mike Snitzer <snitzer@redhat.com>
To: Yael Chemla <yael.chemla@foss.arm.com>
Cc: dm-devel@redhat.com
Subject: Re: md: dm-verity: aggregate crypto API calls
Date: Wed, 25 Oct 2017 11:19:17 -0400	[thread overview]
Message-ID: <20171025151916.GA28274@redhat.com> (raw)
In-Reply-To: <1508921899-24801-1-git-send-email-yael.chemla@foss.arm.com>

On Wed, Oct 25 2017 at  4:58am -0400,
Yael Chemla <yael.chemla@foss.arm.com> wrote:

> Current implementation makes multiple crypto API calls for a single
> block, forcing underlying crypto tfm implementation to "stop & go",
> leading to under utilization of CPU (e.g. SIMD state saves) or HW
> engines. To fix it unify calls to crypto init/update/final into a digest
> call with a single sg which contains multiple buffers.
> 
> This also opens the way later on to parallelizing the work on different
> blocks.
> 
> Tested on physical Arm 32 and x86_64 and virtual ARM 64.
> 
> Performance numbers were not changed.

OK, but what about CPU utilization?  Was it reduced?

Thanks,
Mike

  reply	other threads:[~2017-10-25 15:19 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-10-25  8:58 [PATCH] md: dm-verity: aggregate crypto API calls Yael Chemla
2017-10-25 15:19 ` Mike Snitzer [this message]
2017-12-14  7:54   ` yael.chemla
2017-12-16  1:58     ` Mike Snitzer

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