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Date:   Thu, 09 Sep 2021 16:16:05 +0000
To:     Rob Clark <robdclark@gmail.com>
From:   Simon Ser <contact@emersion.fr>
Cc:     dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org,
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Reply-To: Simon Ser <contact@emersion.fr>
Subject: Re: [PATCH v3 0/9] dma-fence: Deadline awareness
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Out of curiosity, would it be reasonable to allow user-space (more
precisely, the compositor) to set the deadline via an IOCTL without
actually performing an atomic commit with the FB?

Some compositors might want to wait themselves for FB fence completions
to ensure a client doesn't block the whole desktop (by submitting a
very costly rendering job). In this case it would make sense for the
compositor to indicate that it intends to display the buffer on next
vblank if it's ready by that point, without queueing a page-flip yet.