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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In the past there has been writing about Wayland’s model using implicit synchronization of GPU renderbuffers and KMS commits [1] [2].<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">It would sometimes be nice to do that waiting explicitly in a compositor before enqueueing a KMS pageflip that references a buffer who may go on rendering for some time still. This stalls the pipeline.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m wondering whether there’s an API -- maybe something analogous to drmPrimeHandleToFD() – that allows userspace to fetch a waitable fence fd for a dmabuf?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">-Matt<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[1] <a href="https://www.collabora.com/news-and-blog/blog/2022/06/09/bridging-the-synchronization-gap-on-linux/">
https://www.collabora.com/news-and-blog/blog/2022/06/09/bridging-the-synchronization-gap-on-linux/</a><o:p></o:p></p>
<p class="MsoNormal">[2] <a href="https://lwn.net/Articles/814587/">https://lwn.net/Articles/814587/</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b><span style="font-size:13.0pt;mso-ligatures:none">Matt Hoosier<o:p></o:p></span></b></p>
<p class="MsoNormal"><span style="font-size:12.0pt;mso-ligatures:none">Staff Software Engineer<o:p></o:p></span></p>
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