From: Nicolin Chen <nicoleotsuka@gmail.com>
To: Christoph Hellwig <hch@lst.de>
Cc: robin.murphy@arm.com, vdumpa@nvidia.com, linux@armlinux.org.uk,
catalin.marinas@arm.com, will.deacon@arm.com, joro@8bytes.org,
m.szyprowski@samsung.com, linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org,
tony@atomide.com
Subject: Re: [PATCH v2 RFC/RFT 1/5] ARM: dma-mapping: Add fallback normal page allocations
Date: Wed, 24 Apr 2019 12:38:41 -0700 [thread overview]
Message-ID: <20190424193840.GA30240@Asurada-Nvidia.nvidia.com> (raw)
In-Reply-To: <20190424192652.GA29032@lst.de>
On Wed, Apr 24, 2019 at 09:26:52PM +0200, Christoph Hellwig wrote:
> On Wed, Apr 24, 2019 at 11:33:11AM -0700, Nicolin Chen wrote:
> > I feel it's similar to my previous set, which did most of these
> > internally except the renaming part. But Catalin had a concern
> > that some platforms might have limits on CMA range [1]. Will it
> > be still okay to do the fallback internally?
> >
> > [1: https://www.spinics.net/lists/arm-kernel/msg714295.html ]
>
> Catalins statement is correct, but I don't see how it applies to
> your patch. Your patch just ensures that the fallback we have
> in most callers is uniformly applied everywhere. The non-iommu
> callers will still need to select a specific zone and/or retry
> just the page allocator with other flags if the CMA (or fallback)
> page doesn't match what they need. dma-direct does this correctly
> and I think the arm32 allocator does as well, although it is a bit
> hard to follow sometimes.
Okay. I will revise and submit the patches then. I think we
can still discuss on this topic once we have the changes.
Thanks
next prev parent reply other threads:[~2019-04-24 19:38 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-26 23:01 [PATCH v2 RFC/RFT 0/5] Save single pages from CMA area Nicolin Chen
2019-03-26 23:01 ` [PATCH v2 RFC/RFT 1/5] ARM: dma-mapping: Add fallback normal page allocations Nicolin Chen
2019-04-24 15:06 ` Christoph Hellwig
2019-04-24 15:08 ` Christoph Hellwig
2019-04-24 18:33 ` Nicolin Chen
2019-04-24 19:26 ` Christoph Hellwig
2019-04-24 19:38 ` Nicolin Chen [this message]
2019-04-30 15:24 ` Catalin Marinas
2019-05-02 13:26 ` Christoph Hellwig
2019-04-26 20:21 ` Nicolin Chen
2019-04-26 20:25 ` Christoph Hellwig
2019-03-26 23:01 ` [PATCH v2 RFC/RFT 2/5] dma-remap: Run alloc_pages() on failure Nicolin Chen
2019-03-26 23:01 ` [PATCH v2 RFC/RFT 3/5] iommu: amd_iommu: Add fallback normal page allocations Nicolin Chen
2019-03-26 23:01 ` [PATCH v2 RFC/RFT 4/5] arm64: dma-mapping: " Nicolin Chen
2019-03-26 23:01 ` [PATCH v2 RFC/RFT 5/5] dma-contiguous: Do not allocate a single page from CMA area Nicolin Chen
2019-03-27 8:08 ` [PATCH v2 RFC/RFT 0/5] Save single pages " Christoph Hellwig
2019-03-27 18:42 ` Nicolin Chen
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=20190424193840.GA30240@Asurada-Nvidia.nvidia.com \
--to=nicoleotsuka@gmail.com \
--cc=catalin.marinas@arm.com \
--cc=hch@lst.de \
--cc=iommu@lists.linux-foundation.org \
--cc=joro@8bytes.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=m.szyprowski@samsung.com \
--cc=robin.murphy@arm.com \
--cc=tony@atomide.com \
--cc=vdumpa@nvidia.com \
--cc=will.deacon@arm.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).