Hi Peter, On 12/15/21 11:10, Peter Maydell wrote: > On Wed, 15 Dec 2021 at 08:18, Amir Gonnen <amir.gon...@neuroblade.ai> wrote: >> My goal is to simulate a mixed architecture system. >> >> Today QEMU strongly assumes that the simulated system is a *single >> architecture*. >> Changing this assumption and supporting mixed architecture in QEMU proved to >> be >> non-trivial and may require significant development effort. Common code such >> as >> TCG and others explicitly include architecture specific header files, for >> example. > > Yeah. This is definitely something we'd like to fix some day. It's > the approach I would prefer for getting multi-architecture machines.
Am I understanding correctly your preference would be *not* using shared libraries, but having a monolithic process able to use any configuration of heterogeneous architectures? What are your thoughts on Daniel idea to where (IIUC) cores can are external processes wired via vhost-user. One problem is not all operating systems supported provide this possibility. >> Instead, I would like to suggest a new approach we use at Neuroblade to >> achieve this: >> Build QEMU as a shared library that can be loaded and used directly in a >> larger simulation. >> Today we build qemu-system-nios2 shared library and load it from >> qemu-system-x86_64 in order >> to simulate an x86_64 system that also consists of multiple nios2 cores. >> In our simulation, two independent "main" functions are running on different >> threads, and >> simulation synchronization is reduced to synchronizing threads. > > I agree with Stefan that you should go ahead and send the code as > an RFC patchset, but I feel like there is a lot of work required > to really get the codebase into a state where it is a clean > shared library... > > -- PMM >
