A first processing unit such as a graphics processing unit (GPU) pipelines that execute commands and a scheduler to schedule one or more first commands for execution by one or more of the pipelines. The one or more first commands are received from a user mode driver in a second processing unit such as a central processing unit (CPU). The scheduler schedules one or more second commands for execution in response to completing execution of the one or more first commands and without notifying the second processing unit. In some cases, the first processing unit includes a direct memory access (DMA) engine that writes blocks of information from the first processing unit to a memory. The one or more second commands program the DMA engine to write a block of information including results generated by executing the one or more first commands.