I'm interested in adding introspection of disk writes to QEMU for various applications and research potential.
What I mean by introspection of disk writes is that, when enabled, each write passing through QEMU to backing storage would also be copied to an introspection channel for further analysis. I currently have an implementation piggy-backing on the tracing subsystem, but adding binary trace events breaks various assumptions about that subsystem (for example, the stderr backend would no longer be readable when tracing disk writes). I'd really like to someday have introspection in the QEMU mainline, and thus I'm wondering: (1) Should the tracing subsystem be extended to include binary events? or (2) Should a separate "introspection subsystem" be implemented? I suppose we should keep in mind that introspection could include memory, network, etc. if others wanted that in the future (although I am not working on that). -- Wolf
