4 ms·
io_uring combined with ebpf is learning from exokernels AFAICT. XOK for instance had at least three or four in kernel VMs exposed to user space depending on ho
by monocasa 5y ago
io_uring combined with ebpf is learning from exokernels AFAICT.
XOK for instance had at least three or four in kernel VMs exposed to user space depending on how you count them, and was sort of defined by user space using those vms to safely manipulate kernel contexts.
- rwmj 5y agoThose VMs were used to decide who owns (eg) a network packet, which is important for exokernels since the tiny kernel is only there to multiplex the hardware so needs to know ownership, but is really nothing at all like eBPF.
- monocasa 5y agoThey did all sorts of other work too. For one example, their futex() equivalent was a program called a wake predicate that could read from that process's address space to decide if that thread should transition back to runnable. And deciding who owns a network packet is literally how "extended Berkley Packet Filter" go it's start as well.