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<p class="MsoNormal">Hi. We’ve had some problems with XMesaGarbageCollect with multiple threads. For various reasons, we’ve had different Display pointers on different threads. We have a problem when XSync is called on a Display in the list of Mesa buffers,
on a thread where we weren’t intending to handle that Display. That’s because XMesaGarbageCollect goes through every buffer and for each window with a valid Display*, does an XSync and then tests whether the window exists. Various of these could cause some
excitement for us, but we’d love to not XSync things on whatever thread.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">One proposal we have is to have XMesaGarbageCollect accept a Display* argument. The places where it is called all have a Display*, so it could just be passed in. The condition just before the XSync could see whether the buffer’s Display*
is the same as the one passed in. This, in our case, would prevent XSync on a Display* that we’d like to handle on a different thread.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">There is a possibility of leaking a buffer, however, if we didn’t ever call a function that calls XMesaGarbageCollect, like fake_glXDestroyContext() or fake_glXCreateNewContext(), for a particular Display*. But anytime you call one of
those for a Display, any abandoned buffers on that display would be cleaned up.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This isn’t a thread-based approach, but would help our particular situation.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I know there were people concerned with XMesaGarbageCollect last fall, from looking at archives. There were threading issues, concerns about pixmaps, etc. I saw someone proposed a patch, but it wasn’t in the archive. Anything happening
with this?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Would our proposal, having XMesaGarbageCollect accept a Display* and only calling XSync and testing buffers associated with that Display*, cause someone else problems? Would it go far enough to help anyone else?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I could submit my patch, but I want someone familiar with this code to comment.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">thanks<o:p></o:p></p>
<p class="MsoNormal">andy<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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