Re: [PATCH v8 0/7] Add non-strict mode support for iommu-dma

From: John Garry
Date: Mon Sep 24 2018 - 10:35:43 EST

On 21/09/2018 12:03, Robin Murphy wrote:
On 21/09/18 10:29, Robin Murphy wrote:
Hi John,

On 2018-09-21 10:20 AM, John Garry wrote:
On 20/09/2018 17:10, Robin Murphy wrote:
Hi all,

Hopefully this is the last spin of the series - I've now dropped my
touch and fixed up all the various prose text, plus implemented the
quirk support for short-descriptor because it's actually just a trivial
cut-and-paste job.


Hi Robin,

JFYI, I'm trying to test this patchset to get some figures and
provide a tested-by tag, but 4/8 seems to rely on
"iommu/io-pgtable-arm: Fix race handling in split_blk_unmap()" - more
specifically, it seems to rely on the version which Will rewrote in
your patch review, and I am not sure on what branch it exists on, if

Sorry, I should have said this is based on Will's iommu/devel branch:

FWIW I've now pushed out a complete branch here:

git:// iommu/non-strict


So for my network test scenario I was getting a boost @ 250K vs 160K packet(s)/second with strict off/on

For NVMe single disk performance, I was getting a boost @ 582K vs 370K IOPS with strict off/on.

I wasn't seeing such a boost for other storage controller scenario (that's with 6 SSDs), with 776K vs 740K IOPS for strict off/on, but SMMU off was ~800K IOPS.

Tested-by: John Garry <john.garry@xxxxxxxxxx>