From: Steven Price <steven.price@arm.com>
To: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>,
Maxime Ripard <maxime.ripard@bootlin.com>,
Robin Murphy <Robin.Murphy@arm.com>,
"dri-devel@lists.freedesktop.org"
<dri-devel@lists.freedesktop.org>,
David Airlie <airlied@linux.ie>,
Boris Brezillon <boris.brezillon@collabora.com>,
Sean Paul <sean@poorly.run>
Subject: Re: Re: [PATCH v2 6/7] drm/panfrost: Add support for GPU heap allocations
Date: Thu, 25 Jul 2019 17:28:07 +0100 [thread overview]
Message-ID: <482dc837-3ca8-dd93-bbc6-0eb97f3627e7@arm.com> (raw)
In-Reply-To: <20190725161344.GA2950@kevin>
On 25/07/2019 17:13, Alyssa Rosenzweig wrote:
>> Either we should prevent mapping of HEAP objects
>
> I'm good with that. AFAIK, HEAP objects shouldn't be (CPU) mmapped
> anyway in normal use; if you need them mapped (for debugging etc), it's
> no big deal to just.. not set the HEAP flag in debug builds.
>
> Or do you mean GPU mapping?
Sorry, I was being sloppy again![1] I meant CPU mmapped. I agree there
isn't a strong use case for it.
I've been investigating/testing Panfrost kernel with the Arm Mali blob.
Apparently the blob in some cases creates a SAME_VA GROW_ON_GPF buffer -
since SAME_VA means permanently mapped on the CPU this translated to
mmapping a HEAP object. Why it does this I've no idea.
So I've got an interest in trying to maintain compatibility. kbase
places no restriction on mmapping buffers. The main use in the blob for
this is being able to dump buffers when debugging (i.e. dump buffers
before/after every GPU job). Ideally you also need a way of querying
which pages have been backed by faults (much easier with kbase where
that's always just the number of pages).
Steve
[1] kbase+the blob have different terminology here to Panfrost, I do
sometimes struggle with the idea of "not mapped on the GPU" - it's not
really a concept in kbase. All buffers are "mapped" - they just might be
"growable" and not yet full size... :) Hence "mapped" refers to the CPU.
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
next prev parent reply other threads:[~2019-07-25 16:28 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-25 1:09 [PATCH v2 0/7] drm/panfrost: Add heap and no execute buffer allocation Rob Herring
2019-07-25 1:09 ` [PATCH v2 1/7] drm/gem: Allow sparsely populated page arrays in drm_gem_put_pages Rob Herring
2019-07-25 15:36 ` Steven Price
2019-07-25 1:09 ` [PATCH v2 2/7] drm/shmem: Put pages independent of a SG table being set Rob Herring
2019-07-25 15:38 ` Steven Price
2019-07-25 1:09 ` [PATCH v2 3/7] drm/panfrost: Restructure the GEM object creation Rob Herring
2019-07-25 15:40 ` Steven Price
2019-07-25 1:10 ` [PATCH v2 4/7] drm/panfrost: Split panfrost_mmu_map SG list mapping to its own function Rob Herring
2019-07-25 1:10 ` [PATCH v2 5/7] drm/panfrost: Add a no execute flag for BO allocations Rob Herring
2019-07-25 15:45 ` Steven Price
2019-07-25 1:10 ` [PATCH v2 6/7] drm/panfrost: Add support for GPU heap allocations Rob Herring
2019-07-25 13:08 ` Robin Murphy
2019-07-25 21:11 ` Rob Herring
2019-07-26 9:15 ` Steven Price
2019-07-26 9:32 ` Robin Murphy
2019-07-26 16:11 ` Rob Herring
2019-07-25 14:59 ` Steven Price
2019-07-25 15:35 ` Steven Price
2019-07-25 16:13 ` Alyssa Rosenzweig
2019-07-25 16:28 ` Steven Price [this message]
2019-07-25 17:40 ` Alyssa Rosenzweig
2019-07-26 10:43 ` Steven Price
2019-07-26 13:57 ` Alyssa Rosenzweig
2019-07-30 18:49 ` Rob Herring
[not found] ` <20190730185455.GA3205@kevin>
2019-07-30 19:08 ` Rob Herring
2019-07-31 9:22 ` Steven Price
2019-07-25 21:28 ` Rob Herring
2019-07-26 9:20 ` Steven Price
2019-07-30 20:03 ` Rob Herring
2019-07-31 9:30 ` Steven Price
2019-07-25 1:10 ` [PATCH v2 7/7] drm/panfrost: Bump driver version to 1.1 Rob Herring
2019-07-25 13:04 ` [PATCH v2 0/7] drm/panfrost: Add heap and no execute buffer allocation Alyssa Rosenzweig
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=482dc837-3ca8-dd93-bbc6-0eb97f3627e7@arm.com \
--to=steven.price@arm.com \
--cc=Robin.Murphy@arm.com \
--cc=airlied@linux.ie \
--cc=alyssa.rosenzweig@collabora.com \
--cc=boris.brezillon@collabora.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=maxime.ripard@bootlin.com \
--cc=sean@poorly.run \
--cc=tomeu.vizoso@collabora.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