It's unclear how that extension should look like, given that DynP is quite intimately tied to NV's hardware and their particular software stack. It is also unclear if NV will expose this through OpenCL anytime soon, if ever. So AMD doesn't have the hardware to do it (but a restricted form of on-GPU scheduling may be possible, and has been talked about at AFDS this year, see:PG-4271 - Advanced Flow Control in GCN by Pierre Boudier), and it may have to fight an uphill battle against the SW, which is likely going to lead to the use of custom, proprietary and ultimately non-portable extensions.