linux-api.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Shenming Lu <lushenming@huawei.com>
To: Alex Williamson <alex.williamson@redhat.com>
Cc: Cornelia Huck <cohuck@redhat.com>, Will Deacon <will@kernel.org>,
	"Robin Murphy" <robin.murphy@arm.com>,
	Joerg Roedel <joro@8bytes.org>,
	"Jean-Philippe Brucker" <jean-philippe@linaro.org>,
	Eric Auger <eric.auger@redhat.com>, <kvm@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>,
	<linux-arm-kernel@lists.infradead.org>,
	<iommu@lists.linux-foundation.org>, <linux-api@vger.kernel.org>,
	Kevin Tian <kevin.tian@intel.com>,
	Lu Baolu <baolu.lu@linux.intel.com>, <yi.l.liu@intel.com>,
	Christoph Hellwig <hch@infradead.org>,
	Jonathan Cameron <Jonathan.Cameron@huawei.com>,
	"Barry Song" <song.bao.hua@hisilicon.com>,
	<wanghaibin.wang@huawei.com>, <yuzenghui@huawei.com>
Subject: Re: [RFC PATCH v3 4/8] vfio/type1: Pre-map more pages than requested in the IOPF handling
Date: Fri, 21 May 2021 14:37:55 +0800	[thread overview]
Message-ID: <ba8b6039-d053-2657-ae62-deaa30f452d2@huawei.com> (raw)
In-Reply-To: <20210518125826.7ba38b78.alex.williamson@redhat.com>

On 2021/5/19 2:58, Alex Williamson wrote:
> On Fri, 9 Apr 2021 11:44:16 +0800
> Shenming Lu <lushenming@huawei.com> wrote:
> 
>> To optimize for fewer page fault handlings, we can pre-map more pages
>> than requested at once.
>>
>> Note that IOPF_PREMAP_LEN is just an arbitrary value for now, which we
>> could try further tuning.
> 
> I'd prefer that the series introduced full end-to-end functionality
> before trying to improve performance.  The pre-map value seems
> arbitrary here and as noted in the previous patch, the IOMMU API does
> not guarantee unmaps of ranges smaller than the original mapping.  This
> would need to map with single page granularity in order to guarantee
> page granularity at the mmu notifier when the IOMMU supports
> superpages.  Thanks,

Yeah, I will drop this patch in the current stage.

Thanks,
Shenming

> 
> Alex
> 
> .
> 

  reply	other threads:[~2021-05-21  6:39 UTC|newest]

Thread overview: 40+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-09  3:44 [RFC PATCH v3 0/8] Add IOPF support for VFIO passthrough Shenming Lu
2021-04-09  3:44 ` [RFC PATCH v3 1/8] iommu: Evolve the device fault reporting framework Shenming Lu
2021-05-18 18:58   ` Alex Williamson
2021-05-21  6:37     ` Shenming Lu
2021-04-09  3:44 ` [RFC PATCH v3 2/8] vfio/type1: Add a page fault handler Shenming Lu
2021-05-18 18:58   ` Alex Williamson
2021-05-21  6:38     ` Shenming Lu
2021-05-24 22:11       ` Alex Williamson
2021-05-27 11:16         ` Shenming Lu
2021-04-09  3:44 ` [RFC PATCH v3 3/8] vfio/type1: Add an MMU notifier to avoid pinning Shenming Lu
2021-05-18 18:58   ` Alex Williamson
2021-05-21  6:37     ` Shenming Lu
2021-04-09  3:44 ` [RFC PATCH v3 4/8] vfio/type1: Pre-map more pages than requested in the IOPF handling Shenming Lu
2021-05-18 18:58   ` Alex Williamson
2021-05-21  6:37     ` Shenming Lu [this message]
2021-04-09  3:44 ` [RFC PATCH v3 5/8] vfio/type1: VFIO_IOMMU_ENABLE_IOPF Shenming Lu
2021-05-18 18:58   ` Alex Williamson
2021-05-21  6:38     ` Shenming Lu
2021-05-24 22:11       ` Alex Williamson
2021-05-27 11:15         ` Shenming Lu
2021-04-09  3:44 ` [RFC PATCH v3 6/8] vfio/type1: No need to statically pin and map if IOPF enabled Shenming Lu
2021-05-18 18:58   ` Alex Williamson
2021-05-21  6:39     ` Shenming Lu
2021-04-09  3:44 ` [RFC PATCH v3 7/8] vfio/type1: Add selective DMA faulting support Shenming Lu
2021-05-18 18:58   ` Alex Williamson
2021-05-21  6:39     ` Shenming Lu
2021-04-09  3:44 ` [RFC PATCH v3 8/8] vfio: Add nested IOPF support Shenming Lu
2021-05-18 18:58   ` Alex Williamson
2021-05-21  7:59     ` Shenming Lu
2021-05-24 13:11       ` Shenming Lu
2021-05-24 22:11         ` Alex Williamson
2021-05-27 11:03           ` Shenming Lu
2021-05-27 11:18             ` Lu Baolu
2021-06-01  4:36               ` Shenming Lu
2021-04-26  1:41 ` [RFC PATCH v3 0/8] Add IOPF support for VFIO passthrough Shenming Lu
2021-05-11 11:30   ` Shenming Lu
2021-05-18 18:57 ` Alex Williamson
2021-05-21  6:37   ` Shenming Lu
2021-05-24 22:11     ` Alex Williamson
2021-05-27 11:25       ` Shenming Lu

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=ba8b6039-d053-2657-ae62-deaa30f452d2@huawei.com \
    --to=lushenming@huawei.com \
    --cc=Jonathan.Cameron@huawei.com \
    --cc=alex.williamson@redhat.com \
    --cc=baolu.lu@linux.intel.com \
    --cc=cohuck@redhat.com \
    --cc=eric.auger@redhat.com \
    --cc=hch@infradead.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=jean-philippe@linaro.org \
    --cc=joro@8bytes.org \
    --cc=kevin.tian@intel.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-api@vger.kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=robin.murphy@arm.com \
    --cc=song.bao.hua@hisilicon.com \
    --cc=wanghaibin.wang@huawei.com \
    --cc=will@kernel.org \
    --cc=yi.l.liu@intel.com \
    --cc=yuzenghui@huawei.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).