From: Will Deacon <will@kernel.org>
To: Yong Wu <yong.wu@mediatek.com>, robin.murphy@arm.com
Cc: youlin.pei@mediatek.com, anan.sun@mediatek.com,
Nicolas Boichat <drinkcat@chromium.org>,
srv_heupstream@mediatek.com, chao.hao@mediatek.com,
Joerg Roedel <joro@8bytes.org>,
linux-kernel@vger.kernel.org,
Krzysztof Kozlowski <krzk@kernel.org>,
jun.wen@mediatek.com, Tomasz Figa <tfiga@google.com>,
iommu@lists.linux-foundation.org,
linux-mediatek@lists.infradead.org,
Matthias Brugger <matthias.bgg@gmail.com>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v2 0/6] MediaTek IOMMU improve tlb flush performance in map/unmap
Date: Wed, 25 Nov 2020 12:27:19 +0000 [thread overview]
Message-ID: <20201125122719.GB15697@willie-the-truck> (raw)
In-Reply-To: <20201119061836.15238-1-yong.wu@mediatek.com>
On Thu, Nov 19, 2020 at 02:18:30PM +0800, Yong Wu wrote:
> This patchset is to improve tlb flushing performance in iommu_map/unmap
> for MediaTek IOMMU.
>
> For iommu_map, currently MediaTek IOMMU use IO_PGTABLE_QUIRK_TLBI_ON_MAP
> to do tlb_flush for each a memory chunk. this is so unnecessary. we could
> improve it by tlb flushing one time at the end of iommu_map.
>
> For iommu_unmap, currently we have already improve this performance by
> gather. But the current gather should take care its granule size. if the
> granule size is different, it will do tlb flush and gather again. Our HW
> don't care about granule size. thus I add a flag(granule_ignore) for this
> case.
>
> After this patchset, we could achieve only tlb flushing once in iommu_map
> and iommu_unmap.
>
> Regardless of sg, for each a segment, I did a simple test:
>
> size = 20 * SZ_1M;
> /* the worst case, all are 4k mapping. */
> ret = iommu_map(domain, 0x5bb02000, 0x123f1000, size, IOMMU_READ);
> iommu_unmap(domain, 0x5bb02000, size);
>
> This is the comparing time(unit is us):
> original-time after-improve
> map-20M 59943 2347
> unmap-20M 264 36
>
> This patchset also flush tlb once in the iommu_map_sg case.
>
> patch [1/6][2/6][3/6] are for map while the others are for unmap.
>
> change note:
> v2: Refactor all the code.
> base on v5.10-rc1.
Robin -- please can you take a look at this series? I'm not sure I'll
have time to get to it at the moment and you understand how this stuff
is supposed to work.
Cheers,
Will
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
prev parent reply other threads:[~2020-11-25 12:27 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-19 6:18 [PATCH v2 0/6] MediaTek IOMMU improve tlb flush performance in map/unmap Yong Wu
2020-11-19 6:18 ` [PATCH v2 1/6] iommu: Move iotlb_sync_map out from __iommu_map Yong Wu
2020-11-25 16:37 ` Robin Murphy
2020-11-19 6:18 ` [PATCH v2 2/6] iommu: Add iova and size as parameters in iommu_iotlb_map Yong Wu
2020-11-25 16:38 ` Robin Murphy
2020-11-19 6:18 ` [PATCH v2 3/6] iommu/mediatek: Add iotlb_sync_map to sync whole the iova range Yong Wu
2020-11-19 15:33 ` kernel test robot
2020-11-19 16:11 ` kernel test robot
2020-11-25 16:38 ` Robin Murphy
2020-11-19 6:18 ` [PATCH v2 4/6] iommu: Add granule_ignore when tlb gather Yong Wu
2020-11-25 16:38 ` Robin Murphy
2020-11-19 6:18 ` [PATCH v2 5/6] iommu/mediatek: Enable granule_ignore for unmap Yong Wu
2020-11-19 6:18 ` [PATCH v2 6/6] iommu/mediatek: Convert tlb_flush_walk to gather_add_page Yong Wu
2020-11-25 16:38 ` Robin Murphy
2020-11-25 12:27 ` Will Deacon [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201125122719.GB15697@willie-the-truck \
--to=will@kernel.org \
--cc=anan.sun@mediatek.com \
--cc=chao.hao@mediatek.com \
--cc=drinkcat@chromium.org \
--cc=iommu@lists.linux-foundation.org \
--cc=joro@8bytes.org \
--cc=jun.wen@mediatek.com \
--cc=krzk@kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mediatek@lists.infradead.org \
--cc=matthias.bgg@gmail.com \
--cc=robin.murphy@arm.com \
--cc=srv_heupstream@mediatek.com \
--cc=tfiga@google.com \
--cc=yong.wu@mediatek.com \
--cc=youlin.pei@mediatek.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).