On Fri, 2007-05-04 at 16:57 +0100, Keith Whitwell wrote: > That's a special case of a the general problem of what do you do when a > client submits any validation list that can't be satisfied. Failing to > render isn't really an option, either the client or the memory manager > has to either prevent it happening in the first place or have some > mechanism for chopping up the dma buffer into segments which are > satisfiable... Neither of which I can see an absolutely reliable way to > do.
I think we must return an error from the kernel and let user mode sort it out; potentially by breaking up the operation into smaller pieces, or (ick), simply falling back to software. Eliminating per-submit flushing will even make this reasonably efficient as we remap the GTT as objects are used. I don't think we want to support automatic partitioning of the operation in the kernel; punting that step to user mode seems like a sensible option. Certainly presenting all of the objects to the kernel atomically will permit it to succeed if the device can possibly perform the operation; ejecting all existing objects and reloading with precisely the objects proposed by the application can be done, and is even inexpensive on UMA hardware. > The way to get around this is to mandate that hardware supports paged > virtual memory... But that seems to be a difficult trick. Yeah, especially as we don't currently have any examples in our environment. -- [EMAIL PROTECTED]
signature.asc
Description: This is a digitally signed message part
------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/
-- _______________________________________________ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
